Vol:5
Issue:5
Sept-Oct 2017 ISSN: 2349-1418
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Future Superfoods Superfoods: An upcoming trend in Indian food market Quinoa: A Miracle Grain of the Future
Edible oils: Natural healer for fungal infections
Role of Biotechnology for food preservation
Nanotechnology applications in food Industries
Processed food in India Adulterants in Indian Spices
Top 5 carcinogenic food additives and ingredients found in Indian Food
Why Turmeric Isn’t Promoted As An Affordable Treatment For Cancer ?
Anti-cancer effects of vitamin C
Algae could be a future Superfood
Inside Health, Food and Disease
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Macaroni And Cheese Contains Phthalates Chemicals
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Adulterants in Indian Spices
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Superfoods: An upcoming trend in Indian food market
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Quinoa: A Miracle Grain of the Future
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Cancer Immunotherapy: Gaining Much Needed Momentum
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Nanotechnology applications in food Industries
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TE O N L A I EDITOR Printed, Published and Owned by: Dr Vinod Kumar, Scientific Planet Society, Wing No 3/16/2, Prem Nagar, Dehradun, Uttarakhand Printed at Sunrise Offset Printer, 139/2, Yamuna Colony Mkt., Opp PNB Chakrata Road, Dehradun, 284001 Published at Scientific Planet Society, Wing No 3/16/2, Prem Nagar, Dehradun Editor in Chief Dr Vinod Kumar, Scientific Planet Society, Wing No 3/16/2, Prem Nagar, Dehradun, Uttarakhand Associate Editors Dr Virender Singh, Dr Pankaj Kumar Chauhan, Ashwani Mahajan, Dr Ajay Singh , Dr. S. S. Verma Executive Editor Dr Ashok Kumar, Dr M K Tripathi Guest Editor Dr. S. S. Verma Correspondent Geetanjali Bhatia, Manisha Dhatwalia Photography Dr. Vishal Rajput Production Officer Shozeb Javed, Reena Joshi, Dr Varun Gupta Sales and Operation Renu Tomari,Naveen Kathait, Mayank Gupta, Ashish Dobhal, Deepak Singh Cover Design : Manoj Head Office: Dr Vinod Kumar, 12-G Pushpanjali, Enclave, GMS Road, Dehradun, U.K 248001, M-09012784009 Email : scientificindia02@gmail.com Corporate Office: Uma. Goswami, Shop No 1, (s), GF, Designarch Ehomes, UPSIDC, Surajpur, Site-C Near Zeta-1, Greater Noida, U.P. M-9990638673, Email :contactscientificindia@gmail.com
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Future Superfoods Volatile food prices and a growing population mean we have to rethink what we eat. Super food would be the solution. Superfoods are natural products that pack a higher nutritional punch than regular fruit and vegetables. In the beginning, it was all about kale and goji berries, but over the years, health food experts have begun to explore a whole new world of superfoods and health food supplements. In addition to this, we have also explore Health and food related related topics like Why turmeric isn't promoted as an affordable treatment for cancer?, Adulterants in Indian spices, High salt intake associated with doubled risk of heart failure and other stories like Why elephants don't get cancer?, Effect of climate change on rice,Towards LEAD (Pb) free Electronics etc.
Dr. Vinod Kumar Editor-in-Chief
Disclaimer: This magazine is for educational Purposes only, not intended to provide medical advice, diagnosis or treatment. All objection, disputes, differences, claims and proceedings are subject to Dehradun Jurisdiction.
Branch Offices: 1. Surat: Dr. Ashok K. Rathoure, Flat # 107, Akshar Park-A, Near Dhara Complex, Behind Atopnagar, Bhatar Surat -395007 Email : contactscientificindia@gmail.com 2. Hardoi UP: Mr. Gyanendra K. Rathoure, Mayashivraj Sadan Gupta Colony, Hardoi-241001 (UP). 3. Hyderabad: Nilesh Mishra, 6105, Panchavati Apartments, Pragati Nagar, Near JNTU, Kukatpally, Hyderabad, 500072. For(Credit advertisement: : e-volo.com) scienctificindia02@gmail.com, editor@sciencebeing.com www.scind.org
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Algae could be a future Superfood
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lgae are primitive, primarily aquatic, one celled or multicellular plant like organisms that lack true stems, roots and leaves but usually contain chlorophyll. Algae are found in both marine and fresh water. Such as Chlorella,(complex fresh water) are Charophyta. Algae can range from the microscopic (microalgae), to large seaweeds (macroalgae), such as giant kelp more than one hundred feet in length. Most microalgae grow through photosynthesis – by converting sunlight, CO2 and a few nutrients, including nitrogen and phosphorous, into material known as biomass. Algae are very diverse and found almost everywhere on the planet. Global demand for macroalgal and microalgal
foods is growing, and algae are increasingly. Algae is photosynthetic, eukaryotic characterized by high growth rates and high population densities. Under good conditions, green algae can double its biomass in less than 24 hr. Because of high yield, high density biomass is ideal for intensive agriculture and may excellent source for food.
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Protein Protein content differs widely across groups of algae. Various commercial species of the unicellular green alga Chlorella (Fig. 2) contain up to 70 % dry wt protein. Microalgae also have an amino acid profile that compares well with egg, notably containing all of the essential amino acids (EAA) that humans cannot synthesize and must obtain from foods. Some of the algae that are important Chlorella Chlorella is a micro-algae grown in water and is one of the few edible species of it's kind. · 58% of protein. · A good amount of chlorophyll. · A good source of minerals like iron,
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·magnesium and zinc, as well as phosphorus, calcium, iodine, manganese, and potassium. · A good source of vitamins A, C, E, K and Bcomplex. · It is high in essential fatty acids.. · A good source of antioxidants, polysaccharides, beta carotene, and lutein. Spirulina Spirulina is a type of bluegreen algae that is rich in protein, vitamins, minerals, carotenoids, and antioxidants that can help protect cells from damage. It contains nutrients, including B complex vitamins, betacarotene, vitamin E, manganese, zinc, copper, iron, selenium, and gamma linolenic acid (an essential fatty acid). It is largely made up of protein and essential amino acids, and is typically recommended to vegetarians due to its high natural iron content. The high concentration of protein and iron also makes it ideal during pregnancy, after surgery, or anytime the immune system needs a boost. It contains vitamins B1(thiamine), B-2 (riboflavin), B3(nicotinamide), B-6 (pyridoxine), B-9 (folic acid), vitamin C, vitamin D, vitamin A and vitamin
E. It is also a source of potassium, calcium, chromium, copper, iron, magnesium, manganese, phosphorus, selenium, sodium and zinc. Spirulina contains many pigments which may be beneficial and bioavailable. · Calories (81) · Protein (39g) · Dietary fiber (1g) · Sugars (.9g) · Antioxidants: Spirulina microalgae could be a good source of antioxidants due to the presence of carotenoids deriving from chlorophyll, and provide bacterial growth inhibiting action because of certain fatty acids. Microalgae have turned out to be a potential alternative to the use of synthetic sources for these ingredients. Spirulina is a type of microalgae that naturally produces antioxidants (like carotenoids and Xanthophylls), and 4
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antimicrobial compounds like polysaccharides or fatty acids among other beneficial substances. Anti-cancer effects of blue-green alga Spirulina: Spirulina platensis is a blue-green alga used as a dietary supplement because of its hypocholesterolemic properties. Among other bioactive substances, it is also rich in tetrapyrrolic compounds closely related to bilirubin molecule, a potent antioxidant and antiproliferative agent. S. platensis and its tetrapyrrolic components substantially decreased the proliferation of experimental pancreatic cancer. These data support a chemopreventive role of this edible alga. Source: NaturalNews.com, umm.edu, Dr. Axe, Sciencedaily, Ann Hepatol. 2014 MarApr;13(2):273-83
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Why Turmeric Isn’t Promoted As An Affordable Treatment For Cancer? variety of therapeutic properties, including antioxidant, analgesic, anti-inflamm atory and antiseptic activities.
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urmeric is a rhizomatous herbaceous perennial plant of the ginger family, Zingiberaceae. Turmeric is also known as Indian saffron, jiang huang, haridra and haldi. It is a spice grown in many Asian countries. Turmeric is the spice that gives curry its yellow color. It has been used in India for thousands of years as a spice and medicinal herb. Cancer is the most dreadful disease worldwide in terms of morbidity and mortality. The exact cause of cancer development and progression is not fully known. Curcumin, a vital constituent of the spice turmeric, is an alternative approach in the prevention of cancer. Earlier studies have shown the effect of curcumin as an antioxidant, antibacterial, antitumor and it also has a noteworthy role in the control of different diseases. Curcumin has been used extensively in Ayurvedic medicine, as it is nontoxic and exhibits a
According to Daily Mail Online After five years of living with cancer and the ravages of side-effects from repeated unsuccessful treatment, Dieneke Ferguson thought she was finally losing the battle. She had a serious relapse and there seemed little hope. She started a daily dietary supplement of curcumin when approaching her third relapse. In the absence of further antimyeloma treatment, the patient plateaued and has remained stable for the last 5 years with good quality of life. According to BMJ she continues to take oral curcumin 8 g daily without further antimyeloma treatment. After 5 years, her myeloma has remained stable with minimal fluctuation in paraprotein level, her blood counts lie within the normal range and she has maintained good quality of life throughout this period. Kalashnikova et al 2017 reported that attaching curcumin, a component of the common spice turmeric,
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to nanoparticles can be used to target and destroy treatment-resistant neuroblastoma tumor cells (childhood cancer) Wilken et al 2011 reported in his study Curcumin is one such potential candidate, and this review presents an overview of the current in vitro and in vivo data supporting its therapeutic activity in head and neck cancer as well as some of the challenges concerning its development as an adjuvant chemotherapeutic agent. Why turmeric isn’t being used clinically to treat cancer According to another research Salem et al 2014 reported that Curcumin inhibit cancer cell survival and proliferation, and to induce apoptosis without promoting the development of side effects. However, due to its sparing solubility and low bioavailability, curcumin has not yet been clinically used to treat cancer. Curcumin has been shown to have substantial anticancer ability, but its low solubility and poor stability have made its use in medicinal applications challenging. Source: Daily Mail Online, Wilken et al. Molecular Cancer 2011, 10:12. , BMJ.com, Salem et al., RSC Adv., 2014,4, 10815-10829
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Adulterants in Indian Spices
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food adulterant may be defined as any material which is added to food or any substance which adversely affects the nature, substance and quality of the food. India produces a variety of spices and it is a must in every Indian kitchen. The risk of consuming adultered spices is more if we use loose spices. The common adulterants which are added in to these spices are sand, dirt, earth gritty matter, artificial colour, starch, chalk powder, bark, stone, saw dust, lead chromate and argemone seed etc. There are many adulterants which might prove to be a hazard to our health especially if consumed over a long period of time. Chemicals like urea, sodium carbonate, sodium hydroxide, formaldehyde and hydrogen peroxide added to increased shelf life
of milk can be harmful when ingested. They can damage the intestinal lining irritating it. Un- permitted food additives or permitted food additives added in excess͞ both can cause serious damage of health. The use of certain colours like Orange II lead to retardation of growth and affects the proper functioning of vital organs like liver, kidneys, heart spleen, lungs, bones and the immune systems and commonly used metanil yellow could be injurious to the stomach, ileum, rectum, liver, kidney, ovary and testis. All he non- permitted colours can also bring about changes in genes, most having been identified as potential cancer- causing agents. Recently, a major Indian supplier was caught and had to destroy tons of turmeric for dangerous adulteration using metanil yellow and red oxide of lead – the later
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being highly carcinogenic.NCDE X, a company in India, was ordered to destroy 900 tons of black pepper contaminated with mineral oil. Here are following spices which may adultered by some common adulterants. Asafoetida (Hing):Soap stone or other earthy material and foreign resinare the common adulterant used inAsafoetida (Hing). For identification of these adulterants mix little portion of the sample with water and allow to settle down. Soap stone and other earthy material settle down at the bottom. On burning pure asafetida burns like aromatic camphor. Turmeric Powder Turmeric powder can be adulterated by corn flour (starch), yellow coloured talk or sawdust, lead chromate or melanil yellow dye. For identification of these adulterants, add few drop of concentrated Hcl disappear of Instant appeared pink colour on dilution with water shows the presence of turmeric if color persist, metanil yellow colour is present. On addition of concentrated HClE ffervescence will indicate the presence of chalk and yellow stone powder.
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artificial colour in chili powder. Grittine ss on rubbing and settlem ent at the bottom indicate s the presenc e of brick powder and sand. Soapy and smooth touch of white residue at the bottom indicates the presence of soap stone.
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Black Pepper Papaya seeds, black berries are the common adulterant used in black pepper as they are almost similar in size but tasteless (sometimes bitter). For identification of these adulterants, floatthe sample in rectified spirit, the black paper berries sink while the papaya seeds and light black berries float. On pressing with fingers light black berries will break easily while black pepper not. Red Chilli Powder (LalMirch Powder) Can be adulterated by brick powder, salt powder or talc powder and artificial colours like Sudan Red. For identification of these adulterants take a tea spoon of chili powder in a glass of water. Coloured water extract shows the presence of
Saffron The most expensive spice in the world. Saffron is adulterated by coloured dried tendrils of maize cob. Pure saffron gives it saffron colour when dissolved in water as long as it lasts. Artificial saffron releases its color quickly. Cinnamon (Dalchini) Cinnamon is very
commonly replaced with Cassia Bark, which is much cheaper. Cinnamon bark is very thin and can be easily rolled around a pencil or a pen and also have a distinct smell. Cassia barks are tougher and thicker. They rarely give out any aromatic smell. Mustard seed Argemone seed is the common adulterant used in mustard seed For identification of argemone seed in mustard seed use magnifying glass. argemone seed seeds are grainy, rough and black. On pressing mustard seed is yellow in colour while agremone seed is white in colour. Source: epicureandigest, sastasundar.com -Er. Sanjay Kumar, Dept. of Food Tech. Uttaranchal University, Dehradun
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Quinoa: A Miracle Grain of the Future protein, dietary fibre, polyunsaturated fats and minerals. Since quinoa is a good source of so many nutrients, it is important to use it as a part of a balanced diet with many other foods to obtain a good overall nutrition. The macro-nutrient content of quinoa is as follows: Energy (Kcal/100g) - 399 Protein (g/100g) – 16.5 Fat (g/100g) - 6.3 Total Carbohydrate (g/100g) - 69.0.
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ncient grains should be of use to all because they have remained largely unmoved for hundreds or even thousands of years. Quinoa was known to the Incas and called as "the mother of all grains" and was first introduced and cultivated over 5,000 years ago. It is actually a native of South America. Quinoa is one of the oldest crops of the American continent. Quinoa is found in extreme environments such as high mountain plains and alkaline salt flats, to quite moderate, fertile valley areas and moist coastal forests. Quinoa belongs to the Chenopodiaceae family, genus Chenopodium. Its botanical name is Chenopodium quinoa. They are mainly of two types: red and creamy white. It is pronounced as “keen-wah,” this proteinpacked grain contains good amino acid, and is
particularly rich in lysine, which provides healthy tissue growth throughout the body. Quinoa is a pseudocereal and a good source of iron, magnesium, vitamin E, potassium, and fiber. It looks like semolina (suji) and is as adaptable as rice, but quinoa has a richer, nuttier flavor than either of them. Nutritional Aspects: The United Nations called 2013 as the 'International Quinoa Year' in appreciation of the crops high nutrient content. Quinoa is eaten in a manner similar to a grain. It is mainly either cooked and incorporated to soups, or made into flour to be used in bread, drinks or porridges. Quinoa's nutrition is as good as in energy to similarly eaten foods such as beans, maize, rice or wheat. Also quinoa is distinguished as a good source of quality
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Protein With double the protein content of rice or barley, the grain is also unique in amino acids and quinoa contains all nine essential amino acids – including lysine and isoleucine acids, which are lacking in other grains. Depending on the variety, protein in Quinoa ranges from 10.4 to 17.0 percent of its edible portion. The following table 1 shows the essential amino acid content in Quinoa. Vitamins Quinoa is also a good source of B vitamins riboflavin and folic acid in comparison to other grains, same to the amount of thiamine, but lower in niacin. It also contains considerable amounts of vitamin E, though the quantity may be affected after processing and cooking. Amount of vitamin in quinoa is shown in table 2.
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Minerals Quinoa is an excellent source of iron, magnesium and zinc according to the daily mineral recommendations. Dietary Fibre Dietary fibre is the indigestible portion of plant foods, and it is vital for good digestion and also prevents against constipation. Therefore, quinoa is a slowly digested carbohydrate, making it a good low- GI (Glycemic Index) option. The dietary fibre in raw quinoa ranges from about 13.6 to 16.0 grams per 100 grams dry weight. Mainly the dietary fibre was insoluble, with a range of 12.0 to 14.4 grams in comparison to 1.4 to 1.6
grams of soluble fibre per 100 grams dry weight. Fat Quinoa contains fat around (6.3 g) per 100 grams dry weight. Fat is a good source of calories, and also helps in the absorption of fat soluble vitamins. About 50 percent fat is essential polyunsaturated fatty acids linoleic (omega-6) and linolenic (omega-3) acid. Linoleic and linolenic acid are known as essential fatty acids because they cannot be produced by the body. Antinutritional Factor Quinoa, like all plant foods, does contains certain nonnutritive components that can reduce its mineral content and absorption.
Most common are saponins. The saponins are present in many plant species, including spinach, asparagus, alfalfa, and soybeans. The content of saponins varies in quinoa between 0.1 and 5%. Saponins are the principle antinutritional factors present in the seed coat of quinoa and give it a very bitter flavour. They are removed either by the wet method, i.e. washing and rubbing in cold water, or by dry method, i.e. toasting and later rubbing of the grains to remove the outer layers. Quinoa is also high in the compound oxalate, which can bind to minerals such as calcium and magnesium, reducing their absorption in the body.
Table 1: Essential amino acid profile (g/16g nitrogen) of field-grown Quinoa
S.No.
Amino Acid
Amount
1.
Isoleucine
4.0
2.
Leucine
6.8
3.
Lysine
5.1
4.
Phenylalanine
4.6
5.
Phenylalaninc Plus
8.4
Table 2: Vitamin Content of Quinoa in mg/100g dry weight
Tyrosine 6.
Tyrosine
3.8
7.
Cysteine
2.4
8.
Methionine
2.2
9.
Cystine Plus
4.6
S.No.
Vitamin
Content
1.
Niacin
0.5-0.7
2.
Folic Acid
0.0781
3.
Riboflavin
0.2-0.3
4.
Thiamine
0.2-0.4
Methionine 10.
Threonine
3.7
11.
Tryptophan
1.2
12.
Valine
4.8
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Uses: Quinoa is mainly eaten worldwide as bread, upma, boiled, flakes/cereal breakfast, chips, sweets like chocolate bar, fusili, and also as a side dish in a dinner meal, or put in soups, salads, pilafs, and desserts. As the availability of quinoa is increasing, many exceptional cooking methods are being developed, multiplying the ways this food can be prepared. Due to these benefits, quinoa allows greater flexibility in meeting the nutritional needs of humans on long-term space missions. Health Benefits: 1.Help to lose weight: Quinoa is high in protein, which increases metabolism and reduces appetite significantly. The high amount of fiber also helps in increasing the feeling of fullness, making you eat less calories. Low glycemic index of quinoa is another important feature and choosing such foods has been associated with less calorie intake. 2. High in antioxidants: avoids many diseases due to free radicals. 3. Has low Glycemic Index, lowers blood sugar level: The glycemic index is a measure of how quickly foods raise blood sugar levels. Eating foods that are high on the glycemic index can fuel hunger and contribute to obesity. Such foods can cause many of the persistent, Western diseases that are so common today i.e. type 2 diabetes and heart
disease. Quinoa has a glycemic index of 53, which is measured low. 4. Complete Balanced diet : It fulfill the needs of balanced diet due to its nutritional quality. 5. Gluten free: A gluten-free diet is more healthy, when it is based on foods that are gluten free naturally. Gluten-free diets are recommended for people with Celiac disease, severe gluten intolerance. Since Quinoa is naturally free of gluten therefore using it as an alternative of typical gluten-free ingredients can raise the antioxidant and nutrient value of a glutenfree diet. 6. Anti-inflammatory Activity: There are thousands of trace nutrients found in them, some of which are very healthy. This includes interesting molecules called flavonoids, which are plant antioxidants that have been shown to have all types of positive effects on health. It mainly contains the plant compounds quercetin and kaempferol that have been
shown to have antiinflammatory, anti-viral, anti-cancer and antidepressant effects in animal studies. 7. Lowers Cholesterol: Quinoa's fiber content can help in lowering cholesterol levels. Fiber improves digestion, which requires bile acids, which are made moderately with cholesterol. As digestion improves, the liver pulls cholesterol from the blood to create more bile acid, thereby reducing the amount of bad cholesterol LDL (Low Density Lipoprotein). 8. Improves Heart Health: Quinoa provide hearthealthy monounsaturated fat via its oleic acid content, as well as omega-3 fatty acids and alpha-linolenic acids. They decrease LDL and keeps the heart in a good state thus preventing heart diseases. -Sonika Pandey, Research Scholar, Centre of Food Science & Technology, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi
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Edible oils: Natural healer for fungal infections
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nvasive fungal infections are quite prevalent during the last decade or so. In particular, Candida albicans which is a common human fungal pathogen, causes cutaneous , mucosal, and systemic candidiasis. Candida infects in immuno compromised conditions or to the patients undergoing long-term treatment with antifungal drugs. Infection commonly occurs in different body parts such as skin (Ringworm), onychomycosis (fungal infection of the toenails or fingernails), oral candidiasis (oropharyngeal candidiasis ) and vaginal infection (yeast infections) which occurs in almost 75% of adult women. The most common medicines/drugs use to
treatment of fungal infections are Econazole, Fluconazole, Ketoconazole, Alotrimazole, clotrimazole, which belongs to azole class of drugs. However, due to excessive use of these drugs, Candida spp have acquired resistance during the course of the treatment. The conventional treatment of fungal disease is limited and due to increasing the resistance of antifungal drugs has encouraged to find new options from natural sources particularly in aromatic plants and their essential oils, to exploit their antifungal properties. Edible essential oils are extracted from the different types of medicinal and aromatic plants that are
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generally found in Himalaya area, temperate or warm countries. Essential oil is liquid phase, evaporative, transparent, colored, soluble in lipids and organic solvents (Benzene) that have a lower density than water. Many edible essential oils have proved scientifically anti-fungal properties which can help fight against the many common fungus species. A variety of chemical components occur in edible oils such as alcohol, phenol, hydrocarbon, sulphur which also contribute towards role as antifungal agent. Edible oil is important because of their antifungal, antibacterial, antiparasitic properties. The antifungal activity of essential oil is depending on the quantity of their chemical composition and single components. Edible essential oils have been used to prevent oral candidiasis, vaginal, and skin fungal infection etc. The essential oil and their components have different types of targets site. In general oil components act on the cell wall, cytoplasm, lipid binding and DNA binding site of the C. albicans.
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This article at a common platform summarizes the antifungal potential of some of the most common and prevalent edible oils. Clove essential oil (Syzygium aromaticum) Cloves essential oil has been used since ancient time. It is used as a medicine and ingredients in cooking. Generally clove plant are found in Sri Lanka, Indonesia, Brazil and India (Kerala and Tamilnadu). Clove essential oil is extracted from the flower bud part of the Syzygium aromaticum , which plays an important role for the treatment of fungal infection. Clove tree is commonly called as Laung in India. Clove oil contains diverse compounds namely Eugenol (80 to 88%), vanillin, caryophyllene, gallotannic acid, and oleanolic acid, which contains antifungal activities. Eugenol is the major chemical compound present around 82 to 88%. Eugenol inhibits the fungal growth by inhibition of ergosterol biosynthesis or germ tube formation (GFT), and it is also known to affect the mycelia growth. Clove oil is not only acts as an antifungal for treatment of oral candidacies and skin, but also helps improving the immune system. It is also used in many diseases such as
tonsillitis, rheumatic problems, bronchitis, asthma, osteoporosis, breathing difficulty throat, toothache, gingivitis, and few other oral conditions. Lemongrass essential oil (Cymbopogon citrates) Lemograss oil is used in the form of cooking oil and treatment of many diseases since thousands of years all over the world. Lemon grass oils are extracted by steam distillation form the fresh leaves of the lemon grass and used in regular medicine as drugs for the treatment of different types of fungal diseases. It is also may prevent the growth of some fungal species. Lemongrass oil contains flavonoids, phenolic compounds and citral (6585%) which is the major component of lemongrass oil. In addition to citral, the lemongrass oil also consists of small amount of geraniol which has proven antifungal potential. Similarly, Citral has antifungal properties that inhibit the growth of C. albicans. Lemongrass oil is used for the treatment of throat, urinary, Ring – worm and vaginal candidiasis. Lavender essential oil (Lavandula angustifolia) Lavender is a flowering plant and one of the most popular medicinal herbs since ancient times. Lavender oil is obtained
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from the flowers part of the Lavandula angustifolia plant. Lavender is wellknown for its antifungal properties, and its main component are linalool (20 - 50%), linalyl acetate (30 – 60%) and Eucalyptol. The presence of linalool has effect on changing structure of lipid layer present in the cell wall of C. albicans. It is also inhibits the formation of C. albicans biofilms and reduce mature biofilms. The Biofilm plays an important role in the fungal infections as they exhibit enhanced resistance to antifungal drugs. Linalool shows the antifungal activity against C. albicans and it is also inhibits the germ tube formation (GTF). Lavender plant is the type of medicinal herb that is commonly used for the treatment of Athlete's foot (Athlete's foot, also known as Tinea pedis, a fungal infection that affects the foot); dermatophytes causing infection of the skin, hair and nail fungal infections. Tea tree essential oil (Melaleuca alternifolia) Tea tree essential oil (TTO) is obtained by steam distillation of the leaves of Melaleuca alternifoliate (Australian native plant). The main chemical components of tea tree oil are terpinen-4-ol, and γterpinene. Tea tree oil
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are terpinen-4-ol, and γterpinene. Tea tree oil inhibits the germ tube formation (GTF), or mycelial changes in C. albicans. Tea tree oil thus inhibit properties that can be used to treat Candida infections, vaginal candidiasis. It has been also used to treat a mild form of Seborrhoeic dermatitis. Because of ability to kill the fungal species, it is used as antifungal edible oil. The in vivo studies have demonstrated that tea tree oil ointment has potential to treat cutaneous, vaginal, acne, and mucosal fungal infection. The amount of tea tree oil to be used in the treatment of fungal infections depends on the medical condition of patients. Tea tree oil may have beneficial effects against fluconazoleresistant oropharyngeal candidiasis as well. Oregano oil (Origanum vulgare) Oregano oil is dark yellow to pale brown oil which is obtained from the leaves/flowers part of the Origanum vulgare plant. Oregano oil and the oreganum vulgar plant have been used as a traditional medicine or food tasty agents. They contain antifungal properties and high content of phenolic derivatives such as carvacrol and thymol. It is
also contains γ-terpinene, p-cymene. Oregano oil and carvacrol have antifungal properties that play an important role in inhibition of germination and mycelial growth of C. albicans in dose – dependent manner. For the existence of these microorganisms, the structure and function of the plasma membrane of the fungal cells is necessary. Carvacrol has been ability to bind to sterols in the C. albicans membrane. Alteration in the synthesis of plasma membrane results in damage and death of fungus. Oregano oil has been used as both an internal and external agent in treating fungal infections. Oregano oil is an important part of Ayurvedic application which has been traditionally used for treatment of many fungal infections like throat infections, skin, and nail fungal infections. Sesame oil (Sesamum indicum) Sesame oil is naturally obtained from the Sesamum indicum plant. Sesame oil has antifungal properties as well as rich in vitamin E, vitamin B6, zinc, copper, flavonoid phenolic antioxidants. Sesame oil contains major chemical component sesamol, linoleic acid (41%), oleic acid (39%), palmitic acid (8%), stearic acid (5%).
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The presence of Linoleic acid (C18H32O2) and oleic acids in sesame oil shows antifungal activity against the human as well as the plant fungal pathogen. Candidiasis that develop in the mouth or throat is called "thrush" or orrophrenyl candidiasis; it is caused by due to the decreased of saliva secretion, or dry mouth. Linoleic acid is a polyunsaturated fatty acid, which shows the antifungal properties. The antifungal property of the linoleic acid is also attributed to inhibition in the mycileal growth of the C. albicans. Especially sesame oil has been used all over the Asian countries for cooking, including Japan, and its taste is well known to most Asians. Thyme essential oil (Thymus vulgaris) The thyme essential oil extracted from the Thymus vulgaris plant also possesses considerable antifungal activity. Thyme essential oil contains 20–54% thymol, a monoterpene phenolic compound. Studies reported that thymol has ability to inhibit the growth of C. albicans, biofilm formation and ergosterol biosynthesis and membrane integrity. Thymol also has ability to change the hyphal morphology
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which results in reduction of hyphal diameters and destruction of hyphal wall. Thymol is lipophilic in nature which makes it capable of protruding inside the cell membrane of fungus. Kalonji Oil (Nigella Sativa) Kalonji is a traditional medicinal herb. It is found different parts of the world, but mostly in Iran. Kalonji oil is extracted from the seeds of Nigella sativa medicinal herb. The Nigella sativa seed contain, proteins, carbohydrates, alkaloids, oils and essential oil. The major chemical components found in Kalonji oil are, thymoquinone, p-cymene (C10H14) etc. Kalonji oil has been strong antifungal activities, which is using for
treating the various types of fungal disease. Coconut oil (Origanum vulgare) Coconut oil is used in the Ayurvedic treatment of fungal infections since thousands of year. Coconut oil is derived from coconut fruit. Coconut oil is rich in three different types of fatty acid like capric acid, caprylic acid and lauric acid. Caprylic acid is known as their antifungal properties and play an important role in treatment of fungal infections. Capric acid and lauric acid both are combined together to create powerful antifungal combination. This powerful antifungal combination kills Candida by interfering with
the walls of their cells. As a fully natural antifungal, coconut oil is safe low risk and effective way to prevent Candida over growth. Conclusion The utility of natural plantbased oils in antifungal therapeutics is evident from wide ranges of studies. Research on essential edible oils has the potential to identify new bioactive compounds and formulate new functional products for the treatment of fungal infections. -Bablu Kumar, Zeeshan Fatima and Saif Hameed*, Amity Institute of Biotechnology, Amity University Haryana, Gurgaon (Manesar) - 122413
Figure 1. Chemical compositions of different edible oils having promising antifungal activities
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Processed food in India
F
ood is the basic requirement than shelter, cloth, gadgets, status and other daily needs. There is tremendous growth of world population, urbanization and privatization. In spite of increased food production there is danger to shortfall in supply. Consequently, there must be greater and more efficient utilization of the existing food sources and development of new ready to eat processed food. Transformation of raw food ingredients by chemical& physical treatment to form new food product is generally known as processed food. Food processing typically involves activities such as mincing, macerating, liquefaction, emulsification, baking, roasting, pasteurization, pickling and many kind of other
treatments. This treatment enhances taste and shelf life of food with many other benefits to food and agro industry but regular consumptio n with their overdose can increase micro and macro nutrients in individual body. Current dietary behaviors and practices observed in children and adolescents may have harmful consequences on their health. The adverse health consequences that may result from excessive intake of soda and sweetened beveragesÍž fastfood consumption. Rapid urbanization and changes in social and cultural practices have modified the food habits of different community in India. Industrial development in Indian cities has compelled labor from village to migrate to cities in search of employment. It is estimated that within the next ten years, half of the population will be living and working in urban areas. Increase in buying power and long
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hours spent away from home commuting to work places, make convenience foods a necessity in every home. The ever – increasing market for convenience foods, be it tinned, canned, chilled, frozen or preserved operation in food processing. The urban work force does not have the time to follow the traditional recipes and prefers picking up packed, clean, and reasonably priced meals rather than returning home from work and doing domestic chores. Processed food required little or no time to prepare. A packet of potato chips, Frozen Green peas and carbonated drinks are examples of processed food. A packet of instant dhokla, Idly, Dosa and cake are processed food. Processed food need to be handled with care because one source of infection can contaminate thousands of pre packed items. Take away meals should not be kept for a long time. Temperature and time control should be observed during storage. Packed food varies widely in their palatability, nutrient content and cost. The inclusion of processed cereals in the diet has a positive impact on total macronutrient and
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micronutrient intakes in adults and children. Compared with children and adolescents consuming higher amounts of processed cereals which increase amount of sugar, salt and calories in increased amount. All processed food are not as good as they mention in their products in many vegetable and non vegetable soups Corn flour, edible vegetable oil, thickener, softening agent, sugar, salt, dehydrated vegetables, dried glucose syrup, edible vegetable fat, yeast extract powder, hydrolyzed vegetable protein, acidity regulator, flavour enhancer include which is not good in excess amount in regular diet. Flavor enhancers are "colouring agents which are toxic. They put the liver and kidney into overdrive, since these organs have to work extra hard to wash away chemicals from the system and make them safe for the body. This means that the overworked liver is unable to do its regular work. hydrolyzed vegetable protein contains up to 30 per cent MSG, which is known to trigger headaches, rapid heart rate, chest pain and cause nausea. "Moreover, yeast extract powder only increases the bad bacteria (yeast) in the body. This causes problems with the pH levels and creates
acidic blood condition, therefore decreasing immunity. Nowadays life has become hectic and there is hardly time enough even for essential tasks like eating well-cooked meals and snacks. This is the reason that most people are opting for ready to eat processed food and snack items. However, most of these processed items available in the market need not necessarily be healthy. In fact, when it comes to snacks, most of the processed food stuff available in the market is loaded with cholesterol and calories. The market is anticipated to grow on account of increasing working population, growing per capita disposable income, rising per capita expenditure on prepared food, increasing middle class and affluent consumers, etc. With the rising employment opportunities and changing lifestyle of consumers, the demand for ready-to-eat food products in the country is projected to grow during the forecast period as well. India has a large base of young consumers, who form majority of the country's workforce. These young consumers hardly find time for traditional cooking due to their busy life styles which further creates significant potential
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for ready-to-eat food products. Though rising per capita disposable income of consumers, especially upper and lower middle income group, is driving India's ready-to-eat food market, a large chunk of Indian consumers is still price conscious, which poses a challenge for the ready-to-eat food manufacturers and suppliers. Inadequate intakes of fresh fruits, vegetables, fiber rich foods, and dairy and other calcium-rich foodsÍž reduced levels of physical activityÍž and increasing obesity rates indicate a need to revisit the diet and lifestyle characteristics of this age group. Indian food products are hygienically processed and packed taking into consideration all international standards. So, definitely they are not unhealthy though they might be compromised slightly on nutrition. Processed food can be one of alternative source of food. It should not involve in regular diet. Because of high energy and sodium which can increase blood pressure and weight of any individual. -Dr Shuchi Upadhyay Tiwari, Dept. of Food Tech, Uttaranchal University, Dehradun
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Role of Biotechnology for food preservation Food Preservation is the process through which minimizing the biochemical, physical and nutritional damage of food. It is estimated that large amount of food products are lost each year due to spoilage. In each step of food processing contamination may take place to reduce this microbial contamination biotech techniques are applied. So there is some Biotechnological technique used for food preservation. Recent years many food industries represent immense role of food biotechnology. GM plants and animals are used to enhance taste, shell life, nutrition and quality of food. GM yeast and Bacteria are used to produce enzymes in food industry. thermal and highly capable preservation technique. Basically focus on inactivating those bacteria which are responsible for food disease. In this technique high pressure (100-1000 MPa) is applied to inhibit the bacterial growth without disturbing texture, taste, nutrition and mineral quality of food. It is safe for both type of liquid as well as for solid product. Biotechnology tools used for food preservation Recombinant Antifreeze Protein (rAFP): Antifreeze proteins are potent cryogenic protection agents for the cryopreservation of food and pharmaceutical materials. A food assessment expression and fermentation system for the production and secretion of high levels of rAFP was developed. A novel recombinant type I antifreeze protein analogue (rAFP) was produced and secreted by Lactococcus lactis, a food-grade
microorganism of major commercial importance. Lyophilized, crude rAFP produced by L. lactis was tested in a frozen meat and frozen dough processing model. Frozen dough treated with the rAFP showed better fermentation capacity than untreated frozen dough. Breads baked from frozen dough treated with rAFP acquired the same consumer acceptance as fresh bread. So this approach is using present scenario. Use of High Pressure Processing: It is a non
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Hurdles Technology: It is a combination of different preservative methods like use of high temperature in processing, low temperature for storage, increase acidity, low water activity, reduce redox potential and the presence of different preservatives to favor the growth of desirable bacteria and inhibit the growth of pathogenic bacteria. Bacteriocins: These are the complex protein, added during food processingÍž these proteins are active
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against food spoiling microbes. Chelating agents: Due to their binding ability with lipopolysaccaride layer of microbes, chelating agents helps bacteriocins protein to prevent microbial growth. Fermentation starter culture: In fermentation technique complex material is converted into simple substance with the help of enzyme. In this process lactic acid is produced which decreases the pH of medium, due to acidic medium and low water activity, prevent biological growth in medium to insure prolong preservation of food. Radiation: In this process, food products are exposed under the Ď’-radiation having frequency 0.1-0.5 kGy. Radiation cause metabolic changes to increase the shelf life. Products preserved through biotechnology Meat and Sea food: Most of the world population is nutritionally depends on meat (flash of animal) and sea food. Due to high consumer demand and low shelf-life quality its preservation is challenging so new approaches are developed alike use of fermentation starter culture, use of sakacin and pediocin (bacteriocins),
with ultra high pressure and pulse electric field some time chelating agents also used with bacteriocins. The frozen meat treated with the antifreeze protein showed less drip loss, less protein loss, and a high score on juiciness by sensory evaluation. Milk and dairy product: Milk is a good source of calcium and minerals, considering as a complete health drink. Current research indicates that act as carrier for pathogenic microbes. Pasteurization is generally used to decrease the microbial growth, although, it will not applicable a complete sterile milk product. Hence use of Bacteriocins seems good approach to improve the safety and quality of milk or dairy products. Fruits and Vegetables: Soft overcoat of fruits and vegetables are responsible for damage its nutrient value. Controlled and modified atmospheric storage, active packaging, minimal processing, hurdle technology, fogging technology and Ď’ radiation are use for fruit and vegetable preservation. Fermentation Product: The genus Lactobacillus is a heterogeneous group of lactic acid bacteria (LAB) with important implications in food fermentation. The
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ability to colonize a variety of habitats is a direct consequence of the wide metabolic versatility of this group of LAB. Consequently, lactobacilli have been used for decades in food preservation, as starters for dairy products, fermented vegetables, fish and sausages as well as silage inoculants. Lactobacilli have also been proposed as probiotics and microbial cell factories for the production of nutraceuticals. However, a wide range of applications of lactobacilli in food biotechnology remains potential. Biotechnology has tremendous potential for increasing food production and improving food processing in food industries. Productivity must first increase in developed countries before real benefits can be reaped in developing countries. Where biotechnologies are applied to production destined for domestic markets, "demonstration effects" can stimulate developments in other countries. In this case, there is considerable scope for cooperation among developing countries. -Indra Rautela, Dept. of Biotechnology , Uttaranchal University, Dehradun
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High salt intake associated with doubled risk of heart failure
followed up for 12 years through computerised register linkage to National Health Records. Cases of incident heart failure were identified from the Causes of Death Register, the Hospital Discharge Register and drug reimbursement records. The association of salt intake in quintiles (<6.8g, 6.8-8.8g, 8.810.9g, 10.96-13.7g and >13.7g/day) and the risk of an incident new heart failure event was estimated.
Credit: remediesandherbs.com
S
odium is a mineral that's essential for life. It helps in our body fluid balance and also helps in nerve impulses. Salt is also called sodium chloride (NaCl). It consists of 40% sodium and 60% chloride, by weight. Adults should eat no more than 6g of salt a day – that's around one teaspoon. Children should eat less. The daily recommended maximum amount of salt children should eat depends on age: · 1 to 3 years – 2g salt a day (0.8g sodium) · 4 to 6 years – 3g salt a day (1.2g sodium) · 7 to 10 years – 5g salt a day (2g sodium)
· 11 years and over – 6g salt a day (2.4g sodium) High salt intake is associated with a doubled risk of heart failure, according to a 12-year study in more than 4,000 people. High salt (sodium chloride) intake is one of the major causes of high blood pressure and an independent risk factor for coronary heart disease (CHD) and stroke. In addition to CHD and stroke, heart failure is one of the major cardiovascular diseases in Europe and globally but the role of high salt intake in its development is unknown.
During the follow-up, 121 men and women developed new heart failure. In an age, sex, study year and area adjusted model, hazard ratios in the 2nd, 3rd, 4th and 5th salt intake quintiles, compared to the 1st one, were: 0.83, 1.40, 1.70 and 2.10. After further adjustment for systolic blood pressure, serum total cholesterol level and body mass index the hazard ratios were: 1.13, 1.45, 1.56 and 1.75, respectively. Source: American Heart Association, NHS
The study cohort was 19
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Top 5 carcinogenic food additives and ingredients found in Indian Food Food Safety and Standards Authority of India (FSSAI) banned use of potassium bromate as food additive. But still there are more than 300 chemicals used in food industries which are not good for your health. Here are some food additives that are being used in India, despite banning them in many countries due to side effects.
2. BHA (butylated hydroxyanisole) and BHT (butylated hydroxytoluene) Butylated hydroxyanisole (BHA) and the related compound butylated hydroxytoluene (BHT) are phenolic compounds that are commonly used to preserve fats and oils. They are added to food, cosmetics, and packing of products that contain fats to maintain nutrient levels, color, flavor, and odor. Although assumed to be safe in low doses, they may contribute to carcinogenicity at high doses.
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1. Artificial food dyes Colour play important role in the taste and perception of food along with flavour and texture. If food does not look attractive then consumers will probably reject it. But Maximum Indian foods like ice-creams, flavoured milk, candy etc. contain toxic industrial dyes. Synthetic colours have maximum limits this is usually 100 parts per million of the final food or beverage for consumption. Most commonly used illegal colour in India are rhodamine B, orange II, metanil yellow, malachite green, quinoline yellow and auramine.
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Health, Food and Disease
3. Arsenic Arsenic is a natural component of the earth's crust and is widely distributed throughout the environment in the air, water and land. It is highly toxic in its inorganic form. People are exposed to elevated levels of inorganic arsenic through drinking contaminated water, using contaminated water in food preparation and irrigation of food crops, industrial processes, eating contaminated food and smoking tobacco. Long-term exposure to inorganic arsenic, can lead to chronic arsenic poisoning. Skin lesions and skin cancer are the most characteristic effects. Rice and fish is mainly contaminated with Arsenic in India.
4 Sodium nitrate Sodium nitrate is a kind of salt that has long been used to preserve foods. It is added to hot dogs, bacon and other cured meats to help preserve them. Nitrates is the link to an increased risk of cancer in both children and adults. Vegetables with high levels of sodium nitrate include spinach, radishes, lettuce, celery, carrots, cabbage, and beets.
5 Olestra flavor enhancer Olestra is a fat-free and calorie-free chemical used to bring out flavoring in fries, chips, frozen yogurt and all kinds of diet foods. Fat soluble vitamins A, D, E and K binds with olestra, makes you much more prone to cancer.
Source: thoughtco.com, WHO, healthline.com, medindia.net
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Anti-cancer effects of vitamin C Cancer cells are much less efficient in removing hydrogen peroxide than normal cells. Thus, cancer cells are much more prone to damage and death from a high amount of hydrogen peroxide. The very, very high levels of vitamin C used in our clinical trials do not affect normal tissue, but can be damaging to tumor tissue. igh dose injections of vitamin C could help to fight blood cancer and stop it from spreading
H
surgeon Ewan Cameron, first hypothesized the clinical benefits of vitamin C for treating people with cancer.
Vitamin C or L-ascorbic acid is a nutrient found in food and dietary supplements. Vitamin C is a water-soluble essential vitamin. It is a very popular dietary supplement due to its antioxidant properties, safety, and low price. It is an antioxidant and also plays a key role in making collagen.
Vitamin C has a patchy history as a cancer therapy, but researchers at the University of Iowa believe that is because it has often been used in a way that guarantees failure. Most vitamin C therapies involve taking the substance orally. However, the UI scientists have shown that giving vitamin C intravenously and bypassing normal gut metabolism and excretion pathways creates blood levels that are 100 - 500 times higher than levels seen with oral ingestion. It is this super-high concentration in the blood that is crucial to vitamin C's ability to attack cancer cells.
It may not be the cure for the common cold. But the benefits of vitamin C may include protection against immune system deficiencies and cancer also. In the 1970s and 1980s, Nobel Prize winner Linus Pauling, together with
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According to DailyMail.co.uk, superstrength vitamin C doses could be a way to fight leukaemia, 'exciting' early trials suggest. Found in high levels in oranges, peppers and kale, scientists believe it encourages blood cancer stem cells to die. Faulty stem cells in bone marrow often multiply, fueling the growth of fatal tumours, but vitamin C tells them to die, scientists claim. But they warned it is impossible to get the required amount through fruit, and that such high quantities would be given intravenously. Source: webmd.com, University of Iowa Health Care, medicalnewstoday.com, DailyMail.co.uk
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Nanotechnology applications in food Industries
Credit: a24.az
N
anotechnology is the study of matter with at least one characteristic dimension measured in the ranges from 1to 100 nm in scale.It extends its potential from mechanics to medicine and able to create new devices and techniques. Nanoparticle acts as a whole unit in terms of transport and properties andare classified according to their characteristics, size and structures. Nanomaterials is a field that takes a materials science approach to nanotechnology. Food nanotechnology has its history from Pasteurization process introduced by Pasteur to kill thespoilage bacteria, made the first step of revolution in food processing and improvement in quality of foods. Later, the invention
of carbon nanotubes â&#x20AC;&#x153;buckyball fullereneâ&#x20AC;? which is 1nm in size served as the cutting edge discovery to the world of innovation and led to the era of nanoscience and shows an enormous potential in all fields including food sectors.Some important applications of nanomaterials are given below in the various field of food industries. In food Processing: It is the conversion of raw ingredients into food and its other forms by making it marketable and with long shelf life. Processing includes toxin removal, prevention from pathogens, preservation, improving the consistency of foods for better marketing and distribution. Processed foods are usually less susceptible to early
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spoilage than fresh foods and are better suited for long distance transportation from the source to the consumer. All these are made more effective by the incorporation of the nanotechnology nowadays .Nano capsules delivery systems plays an important role in processing sector and the functional property are maintained by encapsulating simple solutions, colloids, emulsions, biopolymers and others into foods. Nano sized self-assembled structural lipids serves as a liquid carrier of healthy components that are insoluble in water and fats called as nanodrops. They are used to inhibit transportation of cholesterol from the digestive system into the bloodstream. In Food Packaging: Food packaging for food requires protection, tampering resistance, and special physical, chemical, or biological needs. It also shows the product that is labelled to show any nutrition information on the food being consumed. The packing has a great significance in preserving the food to make it marketable. Innovations in packaging have lead to quality packing and
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consumer friendly approach in determining the shelf life, biodegradable packing and many more. Nanotechnology in packaging is categorized based on the purpose of the application. In Barrier Protection: The food products are preserved by maintaining it in an inert and low oxygen atmosphere for inhibiting microbial growth and spoilage, thus the material used should be impermeable to gases. Nanocomposites are incorporated in the polymer matrix of the substances due to their large surface area which favors the fillermatrix interactions and its performance. Also the nanoreinforcement's acts as small, barriers for gases by complicating the path of the material, both are known as polymer nanocomposites. Nanoclays are composite materials having complex metallic ores. They are naturally obtained from volcanic ash as Montmorillonite which provides barrier to permeation of gases or polymer based clays prepared by nylons, polyolefin, PET, PA, epoxy resin, poly methane are used for polymer matrix in food packaging to get higher quality. But polyamide based nanoclays have been developed largely and commercialized under the trade names Durethan, Imperm, Aegis and noted for their durability and protection. Various researches have
been developing in nanocomposites from cells and carbon nanotubes since packaging plays a backbone for commercialization of products. In Antimicrobial Packaging: The barriers include natural nanoparticle to control microbial growth which leads to pathogens or spoiling. Silver nanoparticles are used in all forms including biotexiles, electrical appliances, refrigerators, kitchenware's. These nanoparticles show needed action in bulk form, and its ions have the ability to inhibit wide range of biological processes in bacteria. Zinc oxide's antibacterial nature increases with decreasing particle size, it can be stimulated by visible light, and they are incorporated in number of polymers including polypropylene. E. coli contamination can be controlled using titanium dioxide as a coating in packing material. It is also combined with silver to improve disinfection process. Chiston is a biopolymer derived from chitin recently reported antimicrobial properties additional to material for encapsulation. Antimicrobial packaging would be highly healthy and consumer friendly products. In Biodegradable: Pollution is the most concerning factor which affects the environmental characteristics. The effect of nondegradable plastics
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changes the soil nature and accumulation of toxic gases in atmosphere leads to global warming, hence bio degradable plastics came into effect but they lack mechanical strength and permeable to water and gases .These disadvantages are prevailed over by nanotechnology incorporated packaging material made of natural or synthetic nanoparticles having properties like biodegradable, renewable resources having high mechanical strength. Nanoparticles are obtained as the proteins, carbohydrates, lipids from animal and plant materials, also metal oxides nanoparticles and carbon nanotubes are used. In addition collagen, zein, cellulose from corn is synthesized into nanofibers it is highly porous in nature .These nano materials are added along with nanoclays and used for comfort packaging. They also have additional novel properties like sensors, antibacterial action and as biocatalysts. In Smart Packaging: Sensors devices areused to detect the physical quantity of substances and converts into observer readable signals. They are used to regulate the internal environment of the food stuffs and their properties are sensed regularly which is indicated by sensors. A recent report shows that the current smart packaging segment is dominated by oxygen scavengers, moisture
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absorbers and barrier packing product, accounting for 80% of the market. Whereas the bakery and meat products having attracted most nano-enabled packaging technology to date. The food environment is continuously sensed for oxygen content, temperature, pathogens and indicators are used for proper alarming. They also show the shelf life of the products with the help of the nanosensors. Some examples include gold nano particle incorporated enzymes for microbes detection, gas sensing related to condition of food products :nanofibrils of perylene-based fluorophores indicates fish and meat spoilage by detecting gaseous amines. Others also include the zinc oxide and titanium oxide
nanocomposites for the detection of volatile organic compounds. Nanobarcodes are used for tagging and also for security. Thus the use of smart sensors is beneficial to the consumers in terms of better quality identification and producers for rapid distribution and authentication of the food products. In Nutritional Supplements: According to a survey, the total market value of nanofood would reach US$5.8 billion (food processing US$1303 million, food ingredients US$1475 million, food safety US$97 million and food packaging US$2.93 billion) in 2015.Thus making heavy profit to economy.Nanoceuticals, Nutrition-be-nanotech, are commercial names
for supplements. Nanosized powders are used for increasing absorption of nutrients, nanocochleates are considered as effective tool for nutrient delivery to cells without affecting color and taste of food products. Vitamin sprays disperse nanodroplets are used for better absorption of nutrients. Supplementary aspect main involves encapsulation techniques where the needed probiotics, and other products are targeted into the human system with the help of iron and zinc nano structured capsules. Thus, nanotechnology in food supplement is very effective than common supplements because they react more effectively with human cells due to their size. Thus, the wide potential of nanotechnology in overall food industry and its benefits in providing rich nutritional value, quality packaging, smart sensing are to be borne in mind and relevant research for more safer techniques for incorporation of nanotechnology in food industry has to be implemented. -Dr Monu Verma, Dept. of Chemistry, Uttaranchal University, Dehradun
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Macaroni And Cheese Contains Phthalates Chemicals
P
otentially harmful chemicals that were banned from children's teething rings and toys a decade ago. But it is still be present in high concentrations in your child's favorite mealmacaroni and cheese mixes made with powdered cheese. A new analysis found high concentrations of the chemicals known as phthalates in the cheese powder of macaroni and cheese. Phthalates linked to genital birth defects in infant boys and learning and behavior problems in older children. The small study evaluated 30 different cheese products which included natural cheese products, including block
or string cheese, as well as processed cheese slices and the cheese powder found in boxed macaroni and cheese. The analysis found evidence of the chemical in 29 of the 30 products tested. Natural cheeses had the lowest levels of the chemical, while processed cheese products had the highest levels. What are phthalates? Phthalates are a family of chemical compounds primarily used to make polyvinyl chloride (PVC) or vinyl flexible and pliant. Phthalates are used in hundreds of products in our homes, hospitals, cars and businesses. There are many types of 26
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phthalates, which are DBP (di-n-butyl phthalate), DEP (diethyl phthalate), DEHP (di-(2ethylhexyl) phthalate or bis (2-ethylhexyl) phthalate), BzBP (benzylbutyl phthalate), and DMP (dimethyl phthalate). What now? There are few regulation regarding harmful chemicals. So consumer should take matters into their own hands by avoiding types products containing phthalates. 1. Avoid use of fragrances 2. Eat organic 3. Don't use plastic toys Source: KleanUpKraft.org, The New York Times, cnn.com, chemicalsafetyfacts.org, huffingtonpost.com, theguardian.com
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Poor Memory Is A Sign Of Vitamin B12 Deficiency
V
itamin B12 (Cyanocobalamin, cobalamin, methylcobalamin, 5deoxyadenosylcobalamin, adenosylcobalamin, cobamamide, dibencozide, hydroxocobalamin) is a water-soluble vitamin. This means it dissolves in water and travels through the bloodstream. The human body does not store cobalamin. Any excess or unwanted amounts are excreted through urine. Structurally, vitamin B12 is the most complicated vitamin. It is also the largest. Commercially it is produced from the bacteria. It is found in all human cells where its functions range from DNA synthesis and regulation to blood formation and energy production. But just as importantly, vitamin B12 is absolutely essential for the normal functioning of the
nervous system including the brain. Sources Vitamin B12 mainly found in animal products. It occur in plants in less amount. Foods which is the good sources of vitamin B12 are: · Red meat, Eggs and poultry · Fish, especially haddock, and tuna · Dairy products · Some nutritional yeast products · Fortified cereals How much vitamin B-12 should you take? The recommended dietary allowance (RDA) includes the vitamin B-12 you get from both food and any supplements you take. Adult: 2.4 mcg/day Pregnant women: 2.6 mcg/day Breastfeeding women: 2.8 mcg/day
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Vitamin B12 Deficiency Vitamin B12 deficiency can potentially cause severe and irreversible damage, especially to the brain and nervous system. At levels only slightly lower than normal, a range of symptoms such as fatigue, lethargy, depression, poor memory, breathlessness, headaches, and pale skin, among others, may be experienced, especially in elderly people (over age 60). If you've been struggling with your memory, you could be suffering from a vitamin B12 deficiency. The effect of vitamin B12 deficiency is most pronounced in old people. One of the main presentations of this deficiency is cognitive decline. Clear sign of cognitive decline in old age is loss of memory, and confusion while performing simple, everyday tasks. Vitamin B12 can needed to improve memory especially in the elderly who have vitamin B12 deficiency. It shows the good results with addition of folic acid. B vitamins can help cure anemia as well as protect the nervous system. Source: webmd.com, ProgressiveHealth.com, en.wikipedia.org, examine.com
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Eating At Wrong Time Affects Body Weight
A
new high-precision feeding system for lab mice reinforces the idea that the time of day food is eaten is more critical to weight loss than the amount of calories ingested. Mice on a reduced calorie plan that ate only during their normal feeding/active cycle were the only ones among five groups to lose weight, despite consuming the same amount as another group fed during their rest time in daylight, according to the study at UT Southwestern Medical Center. Using high-tech sensors and automated feeding equipment, scientists developed the feeding
system to help answer the difficult question of why calorie-restricted diets improve longevity. Researcher say the new set of tools has already offered fresh insights. Among the findings published in Cell Metabolism, scientists documented how mice on a diet reduced their eating to a very short time period and were unexpectedly active during the day the normal rest period for the nocturnal animals. These data reveal previously unknown relationships among feeding, metabolism, and behavior. Besides affecting weight, scientists believe the timing of food consumption affects
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one's circadian rhythms and may be the route by which dietary habits impact lifespan. The study reinforced this notion by testing the day/night cycles of mice under different feeding schedules. Two groups of mice that were fed at the wrong times during their normal light-dark cycle those with a 30 percent calorie reduction and others with unlimited food access during the day remained active at night, suggesting they might have chronic sleep deprivation. This is an especially important factor for scientists to consider for future research, given that many calorie-reduction studies involve only daytime feeding, which is the wrong time for otherwise nocturnal mice. Without accounting for the timing of food intake, research that examines the effects of calorie reduction on lifespan may be skewed by hidden factors such as lack of sleep and desynchronized circadian rhythms.
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Artificial Sweeteners: Risk Of Weight Gain, High Blood Pressure And Type 2 Diabetes Artificial sweeteners are synthetic sugar substitutes and may be derived from naturally occurring substances, including herbs or sugar itself. It can also term as intense sweeteners because they are many times sweeter than regular sugar. Almost everyone finds pleasure in sweet foods - after all, the taste preference for sweets is inborn. For a child the sweeter food is better. In adults, this preference is somewhat low, but most adults still enjoy an occasional sweet food. But as one want to control weight gain, blood glucose and dental caries, many consumers turn to alternative sweeteners because they to help them limit calories and minimize sugar intake. In doing so, they encounter of alternative sweeteners that is artificial sweeteners. Credit:winnipegfreepress.com
Common Artificial Sweeteners Here are some of the most popular (and dangerous) artificial sweeteners on the market today. They can severely harm your health so avoid these artificial sweeteners. 1. Aspartame It is not heat-stable, that's why it is typically found in drinks and foods that haven't been heated. The study found that â&#x20AC;&#x201C;aspartame may impair
memory performance and increase oxidative stress in the brain. Common side effects of aspartame include headaches, migraines, mood disorders, dizziness and episodes of mania. Comprising phenylalanine, aspartic acid and methanol, these substances can stay in the liver, kidneys and brain for quite some time. 2. Sucralose Sucralose, derived from sugar, was originally
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introduced as a natural sugar substitute. However, in reality, it's a chlorinated sucrose derivative. Sucralose was originally found through the development of a new insecticide compound and wasn't originally intended to be consumed. A study published found that cooking with sucralose at high temperatures can generate dangerous chloropropanols â&#x20AC;&#x201C; a toxic class of compounds. 3. Acesulfame K Composed of a potassium salt that contains methylene chloride, Acesulfame K is routinely found in sugar-free chewing gum, alcoholic beverages, candies and even sweetened yogurts. It cause nausea, mood problems, possibly some types of cancer, impaired
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Health, Food and Disease
liver and kidney function, problems with eyesight, and perhaps even 'autism. In addition to sweetening foods, it's becoming increasingly popular as a
as a “flavor enhancer.” It is heat-stable and routinely found in highly processed foods and baked goods. 4. Saccharin It is heat stable artificial sweetener. It is the primary sweetener for children's medications, including chewable aspirin, –cough syrup, and other over-thecounter and prescription medications. It's believed that saccharin contributes to photosensitivity, nausea, digestive upset, tachycardia and some types of cancer. 5. Xylitol Sugar alcohols aren't absorbed well by the body and cause an allergic reaction for those who have sensitivity to it. In addition, it has gastrointestinal side effects that include bloating, gas, cramping and diarrhea. Risks of artificial sweetener It is difficult but extremely important to curb your sugar cravings for improving your health. There is a huge misconception about
artificial sweeteners. A lot of people think that by using these sweeteners they can not only satisfy their sweet tooth but also minimize the hazards of high intake of sugar. The top dangers of these life threatening artificial sweeteners are given below:
1. Cancer: According to the research, regular use of these artificial sweeteners can result in blood or brain cancer. This is considered one of the biggest risks of these sweeteners, so their consumption should be as limited as possible. 2. Depression, bipolar disorder and panic attacks: The use of artificial sweeteners can create severe conditions of depression and panic attacks. Furthermore, it can also trigger bipolar disease. A person suffering from bipolar disease goes through extreme mood swings. Their immense levels of depression and elevation can only be controlled through medicine. Thus, to avoid such extreme discomfort, you should completely stop taking these artificial sweeteners or at least decrease their intake.
Headaches: The consumption of fake sugar in foods and drinks can also lead to persistent headaches, which in some serious conditions can get worse and turn into migraines. 4. Weight Gain: Many people think that artificial sweeteners make them lose weight. In fact, they are hugely mistaken, because these sweeteners not only don't help them to lose weight but instead are actually one of the leading causes of obesity. It has been observed that people who use these sweeteners gain weight very rapidly. So, if you're weight conscious, stay miles away from these sweeteners. 5. Allergic Reactions: Artificial sweeteners can trigger allergic reactions too. These may include itchy or watery eyes, redness or swelling of the skin, rashes, sneezing, and stuffy or runny nose. 6. Birth Defects or Infertility: Studies show that the use of these harmful sweeteners has also led to infertility or birth defects in men. They contain such ingredients which slow down the male reproductive system.
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8. Blurred Vision and Hearing Loss: Most of these artificial sweeteners are very misleading. They tend to portray that there are no side effects of using them. However, they may also lead to blurred vision and hearing loss as they increase your blood sugar levels. 9. Alzheimer's Disease: Experts have proven that excessive use of artificial sweeteners can also result in Alzheimer's disease. In other words, people who use ample amounts of artificial sweeteners can suffer from memory loss. 9. Cell Damage: Along
with many other dangers, artificial sweeteners are greatly damaging for cells as well. Therefore, their consumption should be very restricted. 10. Nervous System: These are very damaging for the nervous system. Regular use can lead to nervous breakdowns, which can be fatal. Researchers found that artificial sweeteners were tied to a small increase in BMI, weight, waist size, obesity, high blood pressure, heart problems and metabolic syndrome.
All natural sweeteners including maple syrup, coconut sugar, stevia, fruit purees and â&#x20AC;&#x201C;raw honey are great, healthy substitutions. Start working to retrain your palette to enjoy the natural sweetness of foods, not added sweeteners. Try adding other flavors like tangy, tart, warm and savory to please your palette. For example, vanilla, cocoa, licorice, nutmeg and cinnamon enhance the flavor of foods, so you need less sweetness. Source: health.com, fitday.com
Er. Deepika Kohli, Assistant Professor, Uttaranchal University, Dehradun
Healthy Alternatives to Artificial Sweeteners
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Superfoods: An upcoming trend in Indian food market Food consumption is now not just confined to meet the basic energy requirements of body or as a mean for mood modifier and enhancer but also as a source to enhance health attributes naturally. With the growing awareness and globalization, Indian consumers are looking for foods that provide extra benefits beyond meeting the basic nutritional needs. Here comes the role of super foods which are enriched with essential nutrients such as vitamins, minerals, etc, that have many health benefits and are missing from our daily diet. Here is a list of top 10 superfoods arranged alphabetically, that have recently gained importance in the Indian market for their beneficial effects. 1. Amla or Indian gooseberries It is a rich source of vitamin C and also high in antioxidants and apparently possesses anti-ageing properties. It improves eyesight, immunity, hair quality and also helps burn fat. 2. Basil seeds They are commonly known as sabja or chia seeds and popularly used in preparation of faloodas during the summer, basically because for their cooling effect. It is also, an easy source of vitamins, iron, helps control blood sugar levels and aid in weight loss. They are also really good for your gut and can relieve constipation and bloating.
good for heart. It is also a good source of iron, magnesium, copper, manganese and also has plenty of potassium, phosphorus, zinc and selenium. 4. Flaxseed Flaxseed or commonly known as â&#x20AC;&#x153;Alsiâ&#x20AC;? in Indian market is a must in daily diet especially for women population. It have high levels of omega-3 fats that help lowering total
cholesterol and LDL cholesterol (bad cholesterol) levels, lowering blood pressure, promote brain function and prevention of breast, prostate and colon cancers. It is also known as a good source of vitamin B6, copper, phosphorus, folate, magnesium, dietary fibers, manganese and dietary fiber. 5. Ghee It is a myth that (natural) fat
3. Dark Chocolate Dark chocolates are rich in flavanols, polyphenols and antioxidant and thus helps in anti-ageing, cancer prevention, improved heart health and good for overall cholesterol profile. It is
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is bad for you, instead it contains good fat which are essential for our body. It improves immunity and skin texture. It is rich in conjugated linoleic acid (CLA), a fatty acid that protects against plaque, cancer and diabetes. It is rich in omega-3 fatty acids, which lower cholesterol and improve heart health. It s packed with butyric acid, a short-chain fatty acid that has several benefits, one of which is better digestion. It's packed full of fat-soluble vitamins (A, D, E, K). 6.Green Tea Green tea is becoming a common term in Indian market and largely being consumed to aid in weight loss. Besides this, it contains the catechin, epigallocatec hin gallate (EGCG), known to have strong antioxidant properties and has been shown to help prevent and fight cancer.
excellent source of fiber, vitamin B6, potassium, vitamin C, and magnesium. However, the main key therapeutic component of turmeric is curcumin that gives turmeric its superpowers. It has antiinflammatory, anti-oxidant, anti-parasitic, wound-healing and anti-malarial properties, and researchers are finding even more potential uses. 8. Nuts They are an easy source of healthy oils, fiber, protein, vitamins and minerals. Besides this they are loaded with natural antioxidant i.e. Vitamin E. Infact nowadays there is a growing trend to eat it as a snack food instead of consuming junk foods. They are the perfect
addition to a vegetarian diet, providing a quality alternative to many meatbased foods. 9. Oats They are high in fiber, antioxidants, essential vitamins, minerals and nutrients and recently have gained popularity as a breakfast superfood. It helps lower blood cholesterol levels, keep blood sugar levels under control, aid with digestion, and improve metabolism. Source: draxe.com,Timesofindia.indiatimes.com
-Dr. Richa Badola, AP (Food Technology), UCALS Uttaranchal University, Dehradun
7. Turmeric It is a spice which is known for various health benefits from ages. It is an
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Why Elephants don't get cancer?
C
ancer is one of the most dreaded diseases worldwide. There are more than hundred different types of cancer thathave been observed in human. According to World Health Organization over nine million people die due to cancer globally. This figure is alarming and calls for a better treatment regime in dealing with cancer. “Why elephants are free from cancer?” is a challenging question for many scientists and oncologists. Many people have tried to answer in many possible ways. In 1970 an epidemiologist, Richard Peto of the University of Oxford, UK., postulate a hypothesis that the cell division in larger bodied animals may have to divide more times than the smaller animals . The more they divide the chances for mutations are higher. He also points out that there might be an inherent biological mechanism to protect the cells from cancer due to mutations. The main reason for the development of cancer is due to the mutation occurring in one of the guardian gene “TP53”
which is otherwise called as an oncogene. The main role of this gene is to activate proteins that are responsible for repairing the mutated DNA. Once the TP53 gene mutates, then its ability to repair other DNA damages including its own damage cannot be repaired. There are many factors that induce mutation in TP53 gene including genetic makeup, exposure to radiation, toxins etc. Once the TP53 gene has mutated in a cell, that cells undergo uncontrolled cell division and leads to cancer. In a recent study conducted by the Joshua Schiffman, a pediatric oncologist and scientist at the University of Utah in Salt Lake City, U.S.A., has found out that cancer is diagnosed very rarely in elephants . He also points out the reason for this phenomena is due to the increased number of TP53 gene in elephants when compared to humans. While a human has a pair of TP53 gene (one from the mother and other from the father), elephants have 20 pairs of TP53 gene in their genome. These extra copies of TP53 gene help the elephants to overcome cancer. In human it has been reported that missing of one allele of TP53 gene leads to the development of cancer, but in elephants, any genetic malfunctions that could have caused during the process of embryo genesis which results in missing of one or two copies of TP53 gene
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may not lead to cancer. This could be one of the prime reason for elephants to stay away from cancer. Another interesting statement made to answer why elephants are free from cancer is that, elephants are vegetarians and by the same time they habitat in places which are less polluted than where human lives. In order to contradict this statement people may raise questions that what if elephants smoke, or drinks alcohol or have an exposure to radiations. Well, still elephants may stay cancer free as Mel Greaves, a cancer biologist at the Institute of Cancer Research London explains that other than the higher number of TP53 genes the animals with larger body size may get sluggish and thereby their metabolism rates may be slower and thereby the rate of cell division may also be less compared to other smaller and highly active animals including human. It's the fact that elephants get cancer very rarely gives an insight to many cancer researchers to discover the elephant's ability to stay free from cancer. It is also important to investigate if there are any other inherent biological mechanism these elephants hold to sustain DNA dame or mutations and thereby to stay cancer free. -Amjesh R., Department of Computational Biology and Bioinformatics, University of Kerala, Thiruvananthapuram
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Cancer Immunotherapy: Gaining Much Needed Momentum Cancer immunotherapy is an approach of treating cancer by harnessing the potential of body's own immune system. After decades of initial disappointments in the area, the tide has finally changed with some recent successes in clinical trials. The strategy that received clinical validation targets immune suppressingsignaling pathways in the tumor microenvironment, and raises the overall tumor specific T cell populations to fight tumors. Antibodies such as Ipilimumab, Nivolumab, Durvalumab, and Pembrolizumab were developed to target immunosuppression signaling pathways and are now approved by FDA for treating patients suffering from various cancers.In addition to these antibodies, adoptive T cell therapy that engineerpatient's T cells to fight their cancers is showing a great promise in theclinical trials and is being actively pursued to treat cancers.The success of these approaches has cemented cancer immunotherapy potential in patients and even swayed away skeptics. Ipilimumab Ipilimumab is a monoclonalantibody that inhibits cytotoxic T lymphocyte antigen (CTLA4) that is expressed on surface of activated T cells to inhibit their activtion. CTLA-4 inhibits activated T cells through inhibition of CD28 dependent T cell costimulation, a process that is crucial for T-cell activation in response to an antigen. This mechanism of immunosuppression was first elucidated by James Allison from MD Anderson Cancer Institute at USA. In brief, CTLA-4 on T cells interacts with B7 family of accessory molecules expressed on tumor antigen presenting cells (APC), and prevents the typical T cell activation signals between B7 of tumor APC and CD28 of T cells. The interaction of CTLA-4 with B7 is inhibitory in nature and blocks the further activation and
expansion of T cells, and thus effectively control the activation of tumor antigen specific T cells. Ipilimumab by targeting the CTLA-4 antigen, relieves these negative signaling mechanisms leading to activation and expansion of tumor antigen specific T cells to fight tumor cells. Ipilimumab is found to be effective against patients suffering from late stage metastatic melanoma. Phase III clinical trials with Ipilimumab reported a median survival rate of 10.1 months in unresectable stage III and IV melanoma patients treated with Ipilimumab and glycoprotein 100 peptide vaccine relative to 6.1 month survival of patients receiving control glycoprotein 100 peptide vaccine treatment. Among Patients that received Ipilimumab and standard therapy, ~ 21% were still alive after three years while
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it was 12% for patients that received standard therapy. Good data obtained in Ipilimumab clinical trials subsequently led to its approval by FDA to treat metastatic melanoma patients for whom the first line of therapies have failed. Dr. Veerendra Koppolu, Scientist from AstraZeneca, USA has thoroughly presented the clinical development of Ipilimumab in his recent articles. Nivolumab Nivolumab is an antibody that targets an inhibitory receptor Programmed Death-1 (PD-1) that is expressed on the surface of T cells. PD-1 interacts with ligands PDL-1 and occasionally with PDL-2 that are expressed on surface of antigen presenting cells or other immune cells or tumor itself. The PD-1/PDL-1 ( or PDL-2) Interactions render T cell inactive and prevents
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further proliferation and cytokine production. So targeting these interactions using nivolumab blocks the PD-1 and PD L-1 negative regulation pathway. Nivolumab is found to be effective against advanced melanoma and showed 72.9% Survival rate after 1 year and 22% after 3 years in Phase III trial. Nivolumab is approved by FDA in 2015 for treating metastatic melanoma. Subsequent clinical trials also suggest the effectiveness of nivolumab against renal carcinoma and non-small cell lung cancer. Among several forms of immunotherapy, nivolumab appears to have high response rate. This may be because of wide distribution of PD-1 in various tissues (lymphoid, myeloid, dendritic, microvascular endothelial cells) and organs (heart, lung, pancreas, muscle and placenta) suggesting that interactions of PD-1 with its ligand may be important in regulating T cells in peripheral tissues and inhibition of these with nivolumab may trigger a broader activation of T cells responses. Pembrolizumab and Durvalumab Both Pembrolizumab and Durvalumab target PD1/PDL-1 interactions through directly binding to PDL-1 and inhibiting its interaction with PD-1.
Pembrolizumab is approved in 2015 and is now used to treat multiple cancers such as advanced non-small cell lung cancer, advanced melanoma, head and neck squamous cell cancer, classical Hodgkin lymphoma, and advanced urothelial bladder cancer. Durvalumab is approved in 2017 by FDA for patients suffering from late stage urinary bladder cancer. Adaptive T cell therapy Steven Rosenberg from National Institute of Health (NIH) in USA have developed chimeric antigen receptor (CAR) T cell based adaptive immunotherapy technology which involves genetic engineering of patient T cells to target tumor cell. In CAR-T therapy, patient's T cells are engineered in such a way that they will provide T cell with exquisite tumor antigen specific recognition, T cell activation, and proliferation. The major advantage of CAR T cell therapy is that it is not affected by mechanisms that are developed by tumor cells to evade immune responses. It is independent of MHC dependent antigen presentation which generally limits endogenous T cell response when tumors downregulate MHC expression on their surface. CARs can detect a variety of antigens expressed on
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tumor cell surface including proteins, lipids, carbohydrates for which antibodies can be generated. CAR therapy can overcome the limitations of poor endogenous T cell immune response that are the result of cancer cell induced down regulation of the costimulatory molecules. Although CAR T cell therapy is relatively a new immunotherapy approach, the clinical results are eyecatching. Clinical studies reported that 27 (90%) out of 30 acute lymphoblastic leukemia (ALL) patients that have undergone CAR T cell therapy targeting CD19 (CTL019) responded with a complete remission. A high response was achieved even for patients with previously failed stemcell transplantation (15 out of 30). This unprecedented early success of CAR T cell therapy raised enormous interest and now became the focus of many clinical trials. This first CAR-T cell therapy against acute lymphoblastic leukemia is under FDA review and the recent FDA advisory committee meeting unanimously (10:0) recommended the approval of this therapy. Source: medcraveonline.com, juniperpublishers.comf
-Dr. Veerendra Koppolu, Scientist, Biopharmaceutical Development, Gaithersburg, Maryland, USA
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Effect of Climate Change on Rice: Challenges and Mitigation through Plant Breeding (6) Natural disasters such as heat waves, salinity, prolong drought period and floods brought about by climate change.
M
ore than 50 per cent of the world population depend on rice for their survival. It feed 4 billion people i.e 56% of world population. Rice is the main staple food of India and the world. The Goal of United Nations is to reduce poverty, hunger and malnutrition of the world. This was the main reason for the United Nation for the announcement of 2004 as the “International Year of Rice”. Rice is grown by 144 million farm families i.e. 25% of the world farmers. Harvested from 166 million Hectare i.e 10% of the world crop land. Rice is the source of more than 500 calories per person per day for over 4 billion people (FAOSTAT 2016). Climate change is estimated to affect 20 million hectares of the world's rice-growing area adversely, mainly in India and other Asian countries. It is forecasted
by the International Food Policy Research Institute that by 2050, the rice prices will increase between 32% and 37% as a result of climate change due to the reduction in rice productivity by 14% in South Asia, 10% in East Asia and the Pacific and 15% in sub-Saharan Africa. Global population is predicted to rise to over 9 billion by 2050, which will lead to a 25% increase in the demand for rice. Factors affecting climate change Evidence of climate change that affect the productivity of rice mainly in Asian countries such as (1) Increase in temperature, (2) Irregular rainfall, more water demand, (3) Attack by known and new pest and diseases, (4) Plant Breeding Impact, (5) Emission of methane from rice fields and
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Global Warming Increase in the average temperature of the earth's atmosphere and oceans can cause global warming. Increase in the temperature of earth surface due to trapping of heat from the sun by the green house gases such as carbon dioxide, water vapour, nitrous oxide and methane. Rice production is one of the major contributors of green house gas like Methane. These gases trap the heat coming from the sun, and not revert back into the space, which cause rise in the temperature of earth surface. The increase in temperature of earth surface results in climate change and altered the weather pattern. In 2001, the 'UN-sponsored Intergovernmental Panel on Climate Change' reported that worldwide temperatures have increased by more than 0.6°C in the past century and estimated that by 2100, average temperatures will increase by between 1.4°C and 5.8°C (Nguyen, 2005). And this uncertain climate change leads to outbreaks of harmful insect pest and diseases. That has greater harmful impact on agriculture, forestry and
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in temperature is emitted by both upland and lowland rice under slash-and-burn shifting cultivation. Moreover, many study revealed two major factors that greatly affect the productivity of rice, first, elevation in CO2 augment emission of methane from paddy crop, and second, increase in temperature caused a decline in rice production. Rice cultivation is responsible for more than 10% of release methane from rice field. Since more than half of the worlds' humanities are dependent on rice, the production systems for rice crop are, thus, vital for the reduction of hunger and poverty. Temperature limit for growth of rice is 45°C and temperatures more than this will adversely affect its productivity. The temperature ranges for rice at different Phase after germination is 35–31°C
forestry and ecosystems.The increase in temperature also disturb the normal livelihood of people, animals and plants. Rice Productivity and Global Warming High carbon dioxide concentration in the atmosphere and rising temperature makes rice crop to increases temperatures would decrease the rice production globally (Nature climate change). As rice is C3 crop is less efficient in CO2 fixation than C4 crop. Both lowland and upland rice cultivation and rice production under slashand-burn shifting cultivation results in the emission of methane and nitrous oxide gases and, thus, contributes to global warming. Green house gases like methane and Nitrous oxide, contributes to global warming with rise
whereas for ripening it is 20–29°C (Table 1). The temperature is one of the major factors that may affect and produce abnormal symptoms in rice (Table 2). Such uneven increase in temperature during the crop growth period, notably during highly sensitive reproductive and early grain-filling phase of rice (Oryza sativa L.), leads to decreased biomass, grain production and quality. Rice Productivity and Water Manage Climate change is expected to affect water demand for rice via changes in rainfall regime, soil water balance, and evapotranspiration. Higher temperatures and increased variability of precipitation are predicted to increase water demand and could potentially require more irrigation in lowland rice-growing areas.
Table: 1. Critical temperatures for the development of rice plant at different growth stages
Growth stage Germination Seedling Emergence Rooting Leaf Elongation Tillering Initiation of panicle primordia Panicle Differentiation Anthesis Ripening
Critical temperature Low High 16-19 45 12 35 16 35 7-12 45 9-16 33 15 15-20 30 22 35-36 12-18 >30
Medium 18–40 25-30 25-28 31 25-31 30–33 20-29
Source: From Yoshida, S. 1978. Tropical Climate and Its Influence on Rice. IRRI Research Paper Series 20. Los Baños, Philippines, IRRI.
Table: 2. Symptoms of heat stress in rice Growth Stage Vegetative Reproductive anthesis Ripening
Symptoms White leaf tip, chlorotic bands and blotches, white bands and specks, reduced tillering, reduced height Reduce spikelet number, sterility Reduced grain-filling
Source: From Yoshida, S. 1981. Fundamentals of Rice Crop Science. Los Baños, Philippines, IRRI. 269 pp.
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The rice crop is affected both at the vegetative and reproductive stage due to a rise in temperature and, hence, productivity is also affected. The temperatures required at different crop growth phases are given in Table 1. High temperatures may result in various possible injuries to rice crops given in Table 2. High temperatures for 1â&#x20AC;&#x201C;2 h at anthesis may result in sterility of the rice crop. The change of precipitation due to climate change has presented obvious regional trends. At the global scale, precipitation tended to increase in the high latitude regions of the Northern Hemisphere and in the tropical regionsÍž while in the semi-tropical regions, the precipitation decreases over the past several decades. Drought effect on Rice Drought is the most serious constraint and devastating for rice growing areas, affecting millions of land in Asian countries. In some states in India, drought is expected to be more frequent especially in northeastern India, Jharkhand, Orissa and Chhattisgarh. Moreover drought caused yield loss of more than 35 %. Drought affected more than half of India's crop land and led to a huge loses in crop production during 1987 and 20022003. Rice is particularly very much sensitive to moisture stress. Drought severely causes poor germination, reduced tillering, low spikelet fertility or creates sterility in flower,
reduced plant height, degrade seed quality, create chalkiness and delays flowering. That finally affects the yield or economic loss. Respiration rate increases due to rise in temperature, that's cause rice less productive. It is expected to fall crop yield significantly due to increase in temperature by 2050s. Flooding and Salinity effect on Rice Productivity Flooding is a serious hindrance to rice production, mostly in rainfed lowland areas of the globe. The flooding especially found in deltas and major river basins of tropics that has provided the sustenance for the rice production. Moreover, flooding also a cause of yield fluctuations because of unpredictable rainfall patterns and unsteady drainage of most of the rice fields. This results in overabundance water in these fields for varying depths and periods. The flooding is categorized into four types depending on the plant character and varietal types that are remodelled to the situations: (1) Flooding during germination (2) Flash flood (3) Stagnant flooding (4) Deeper stagnant flooding. Particular field, more than one of these situations can occur in the same season or in different seasons. Flooding can hit rice crops at any phase of growth. The chances of survival are extremely low when completely submerged
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during the crop's vegetative stage. Submergence causes reduction in plant growth leading to the death of rice plant. Major part of land suited to rice production in Asia and is currently not in use due to accumulation of high salt. Rise of temperatures due to Climate change prompt high evapotranspiration rates leading to salt accumulation in rice fields. Rising sea levels brings salt water in land, which contributes to soil salinity. In Indian coastal areas, salinity affects more than hectares of land that can otherwise be used for rice cultivation. Effects of salt stress on rice are similar to those of drought leading to lower yields. It has been estimated through worldwide that more than 20% of total cultivated and 33% of irrigated agricultural lands are highly affected soil salinity. Moreover, the coverage of salinized areas are increasing at a steady rate of 10% annually for many reasons, including low precipitation, excessive evaporation, weathering of rocks, regular irrigation with salinized water, and improper cultural practices. It has been expected, due to the unpredictable climate, more than 50% of the well suited land for rice farming would be salinized by the year 2050. Rice is highly sensitive to salt stress in its early growth stage , this poses a major problem to rice farmers because transplanted seedlings may all die
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and establishing a sufficient crop stand becomes very difficult. Biotic stresses affecting Rice: Disease and Insect One of the major challenges in rice production are outbreaks of new insect pest and diseases. A part of the biotic stresses insect pests leads to damage about 1015% yield losses. The average yield losses in rice have been estimated to vary between 21-51 per cent. The key pest in paddy crop causing 25-30%, 1070% and 15-60% yield losses, were yellow stem bore, plant hoppers and gall midge respectively. At National level, stem borers accounted for 30% of the losses while planthoppers (20%), gall midge (15%), leaf folder (10%) and other pests (25%). The incidence of insect pests and resultant yield losses vary depending upon the age of crop. Study conducted by the International Rice Research Institute (IRRI), it was found that, on average, farmers lose 37% of their rice yield to pests and diseases, and that these losses can range between 24% and 41% depending on the production situation. The Challenges and mitigation through Plant Breeding 1. To develop and release new rice cultivars
with better adaptation to high temperature and other climatic stresses. Droughttolerant varieties which have been released in several countries and are now being planted by farmers. These include Sahbhagi Dhan in India, the Sahod Ulan in the Philippines, and the Sookha Dhan and tarharra1 varieties in Nepal. 2. Submergence tolerance of rice crop plants has substantially been improved by introgressing the “Sub1” gene by MABB into popular rice cultivars in many rice-growing areas in Asian countries that favour resistance to submergence for up to 12-14 days. Flood-tolerant varieties that have been released and are now being planted include Swarna Sub1 in India, Samba Mahsuri in Bangladesh, and IR64Sub1 in the Philippines. These are improved through Marker assisted backcross breeding method. Numerous drought tolerance varieties released in 2009 with yield advantage of 1-3.5 t/ha.
406”Luna Barial” and CSR43 ( Sodic Soil tolerant) released in India. Tolerant cultivars released in Bangladesh include BRRI dhan 47, BRRI dhan 53, BRRI dhan 54, BRRI dhan 8 and BRRI dhan 61. 4. Several Insect Pest and disease resistant variety have been developed to overcome the loss caused by the attack of biotic stresses. 5. Conversion of C3 rice to C4 rice by the application of genetic engineering, that may overcome the problem of loss caused by rise in CO2 level in the atmosphere. As C4 plant has high efficiency to extract CO2 from the atmosphere because C4 plant have PEP case enzyme to produce first stable product of 4 carbon compound i.e malic acid. Work is being going on to integrate the C4 photosynthesis system into rice at IRRI since 2012. -Dilruba A Bano and Kuduka Madhukar, Department of Genetics and Plant Breeding, Institute of Agricultural
3. With the new techniques of plant breeding and genetics several cultivars of salinity and alkalinity tolerant cultivars released in India and Bangladesh. These include CR Dhan 405”Luna Sankhi”, CR Dhan
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Sciences, Banaras Hindu University, Varanasi-221005, India
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Towards LEAD (Pb) free Electronics
I
ndispensible lead
Lead is not a problem when contained in electronic equipment, however, when electronic components are deposited in landfills, people may scavenge for equipment and break it open, or the lead may leach out of landfills and into drinking water. The risk is compounded in countries that receive massive imports of electronic waste. Use of electrical and electronic products in the society all over the world is growing alarmingly fast, which for a large part end up as Waste Electrical and Electronic Equipment
(WEEE) when new and cooler gadgets become available in due course of time. This means that the amount of WEEE is constantly increasing worldwide. However, some countries have developed expertise to recycle and reuse WEEE in the production of new equipment. Most smartphones and other electrical or electronic products contain small amounts of lead, which doesn't sound like a big problem on its own. But when there are many billions of such products, either in daily use or gone astray, the total sums up to very large amounts of lead
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-- which is a toxic heavy metal. Moreover, lead is often used in materials that are piezoelectric, which means that they consist of crystals that produce an electrical voltage when pressure is applied. Therefore, these materials are widely used as pressure sensors. The reverse function is also important: if we apply an electrical voltage to such materials, they will expand and for instance give a tiny engine that can move very small things around. The most extensive use of piezoelectric and leadbased material occurs in transmitters and receivers, where the ceramic compound lead zirconate titanate (also called PZT) has been difficult to replace. PZT contains approximately 60 per cent lead by weight. Therefore, the environmental authorities in several countries have agreed to limit the use of lead in electrical and electronic equipment. Products must contain no more than 0.1 per cent by weight of lead in order to be approved for environmental friendly electronics marking. But there are always exceptions, especially when there are no alternative materials to be found.
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Lead poisoning Lead poisoning can cause a variety of symptoms and it has even been claimed that lead poisoning caused the fall of the ancient Roman Empire. The Romans used lead compounds in their aqueducts, and lead acetate also called Sugar of lead was even used as a sweetener in wine. As we have become completely dependent on the production of the electronic products, the problems with lead pollution are much greater. The problem with lead is that the element is absorbed into the body and displaces other chemical substances in such a way that important biological functions are disturbed. Children and pregnant women are especially vulnerable, because lead is easily taken up in bones when growing. Lead exposure, even at low levels, is well known for its harmful effects in general and on children in particular. The linchpin of electronics Solder is the linchpin of electronics manufacturing and lead has been ideal for solder, without which, it's difficult to achieve a proper electronic connection that is durable and reliable. The whole electronics infrastructure was designed
around the melting point and physical properties of lead. Lead is malleable and thus easy to work with, and it doesn't fracture. When lead is combined with tin in the correct proportion (63% tin to 37% lead), the resulting alloy has a low melting point of 183°C, which is another advantage. If not operating at really high temperatures, we have more control over processes, so that the processes aren't sensitive to slight temperature variations, which are costly to control. Low temperatures also mean less strain on the equipment and materials (such as printed circuit board and components) that must be heated as part of the assembly process. The electronics industry is learning to do without: it has to abandon one of its long-time staples, lead–tin solder. For decades lead–tin solder has been used to attach electronic components to printed wiring boards. However, with the body of evidence pointing to serious adverse health effects of lead, the search for a replacement has spawned intense effort in the electronics industry and in universities. Now scientists think they may have found some promising leads: solders made of alternative alloys and polymer formulations known as electrically
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conductive adhesives (ECAs). Alternative alloys The main approach to replacing lead in solder has been to look for other metals as substitutes. Electronics manufacturers began to look for alternative metals in the 1990s. A search by industry experts for possible replacements for lead–tin solder winnowed down 75 metal alloy alternatives to about half a dozen. The industry eventually selected a tin–silver–copper combination as offering the most reliability and ease to work with as a replacement. The formulation—95.5% tin, 3.9% silver, 0.6% copper—is also known as SAC solder, for the first letters of the chemical symbols of each of the elements (Sn, Ag, Cu). Experts say that Tin–silver–copper appears to have at least as good reliability if not higher reliability than tin–lead. With a melting point of 217°C, SAC solder also is closest in melting point to the conventional lead–tin solder. This does mean, however, a yet-unquantified increase in energy use. Furthermore, the higher temperature may pose problems for the electronics industry. Higher temperatures mean
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more stress on components and the entire manufacturing process. Higher temperatures also mean increases in the time it takes to make products, because more time is required to heat and cool the products during the course of their manufacture. SAC solder is used widely in the industry today. However, many of the components being made could not withstand the higher temperatures. That required re-engineering and getting new materials, not only for newer products but for older products. All the older products that had been in production for ten or fifteen years had to be converted over to high temperatures. There are also short-term consequences of using the new solder. Anytime there is a change in materials, there is a learning curve in using the new materials. A stickier approach A more experimental alternative to lead–tin solder is the use of ECAs. These are polymers, such as silicone or polyamide, containing tiny flakes of metals such as silver. The polymers adhere to the printed circuit boards, and the metal flakes conduct electricity. ECAs offer a range of advantages. Silver's electrical conductivity is very high, and its electrical resistance is very low
, he points out. “If the current-carrying capability can be boosted, ECAs can replace solder. There is another benefit, the temperature required to apply ECAs to circuit boards is far lower than that required for lead-based solder—150°C compared to 183°C. Moreover, subjecting of the components to lower temperatures and thus less thermomechanical stress enhances their reliability. At present, ECAs are available for a small number of applications requiring low power—for instance, liquid crystal displays—though they are not ready for the marketplace in general, where greater amounts of current are needed. Solder replacement Lead-free solder technology is not new. For years, many manufacturers have used lead-free alloys in niche applications to provide a higher melting point or to satisfy particular material requirements. However, the goal of today's lead-free solder research is to determine which alloys should be used to replace the estimated 50,000 metric tons of tin-lead solder currently used each year. Eliminating lead, which is abundant and inexpensive, and replacing it with another element(s) may well increase the cost of raw materials.
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· The materials chosen to replace lead must meet a variety of requirements: · They must be available worldwide in quantities sufficient to supply global needs. · The replacement alloy must also be considered non-toxic. · The substitute alloys must be able to take all forms used by the electronics industry · Substitute alloys should also be recyclable These mandates will force the electronics industry to convert from solders that have traditionally contained small amounts of lead (Pb) to alternatives that are Pb-free. While military electronics are currently exempt from these Pb-free imperatives, the consumer market drives the electronics industry, not the military, and what is permitted in consumer electronics will dictate the availability of parts and materials. Electronics for high reliability applications, such as in military equipment, rely heavily on commercial piece parts, circuit boards, and assemblies, the majority of which have transitioned or will transition to Pb-free. Even as efforts to replace lead in solder move ahead, there still appear to be concerns about the impact that newly implemented metals will have
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Technology
on human and environmental health. â&#x20AC;&#x153;The alternatives to lead have not been researched as well as lead in terms of potential health and environmental impacts. Step in the non-toxic direction The main impetus for the industry to leave lead behind is a ban on lead in electronics already imposed by the many countries. Under these restrictions lead must be replaced by other substances in electronic equipment. In practice, it is not possible to limit or stop the use of lead in such products if we don't have other materials that can deliver the same benefits without being significantly more expensive. Therefore, scientists at the Department of Chemistry at the University of Oslo (UiO) have tried to develop new materials that can replace the lead-containing materials. They have taken a long step in a right and non-toxic direction. The work is related to making thin films of a material that has the potential to replace lead in electrical and electronic products. The material contains the common elements sodium, potassium and oxygen in addition to the metal niobium, and has no known harmful environmental effects. Strictly speaking, the material isn't completely
new, but it has been difficult to produce it on a form that can be used in applications. But now, this problem has been solved by using the technique called Atomic Layer Deposition (ALD) and researchers are now able to make thin films with potassium and sodium as important ingredients, which is something nobody else has been able to do earlier. The innovative thin film consists of crystals, which is created by depositing one atomic layer at a time on a substrate made of silicon. The researchers are far ahead internationally in the use of ALD technology, and research colleagues both far and near have noted that they now are able to make these films with sodium and potassium. Researchers add that there are still some issues that need to be solved before the new thin films can be used in products. They are able to produce the films in the laboratory, so the next step is to find a way to produce quantities that are large and cheap enough to be used industrially. We must also find a way to produce crystals where all the piezoelectric properties points in the same direction, before the materials can be used as sensors or small motors.
mobile phones, televisions, computer monitors, and household appliances into landfills worldwide poses a potential environmental hazard if the lead seeps into local groundwater. Lead has already been removed from paint and from gasoline. It was only a matter of time before the electronics manufacturing process went lead-free. These mandates will force the electronics industry to convert from solders that have traditionally contained small amounts of lead (Pb) to alternatives that are Pbfree. While military electronics are currently exempt from these Pb-free imperatives, the consumer market drives the electronics industry, not the military, and what is permitted in consumer electronics will dictate the availability of parts and materials. Electronics for high reliability applications, such as in military equipment, rely heavily on commercial piece parts, circuit boards, and assemblies, the majority of which have transitioned or will transition to Pb-free. -Dr. S. S. Verma, Department of Physics, S.L.I.E.T., Longowal, Distt.-Sangrur (Punjab)-148106
Discarding of millions of
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Space
How do we detect objects in the Universe today?
F
or millennia, mankind gazed out into the mesmerizing night sky, without knowing that what they were seeing were stars just like our Sun and billions of other galaxies making rest of our Universe. The ``seeing by eyes" later turned into ``observing through telescopes" and today the detection and discovery of objects in the heavens depends far more than ever on statistical analysis tools, theoretical models and algorithms that are built by the scientists down herefor optimally extracting out interesting objects from the astrophysical data sets which exist out there. The first ever significant and noteworthy detections of objects in the cosmos made by a member of homosapiens from the planet Earth, in my view, can be traced back to the time of Tycho Brahe's
observa tions. On Novemb er 11, 1572, on his way back home, Brahe was contem plating stars in the clear sky when a new and unusual star almost as bright as Jupiter sitting in the Cassiopeia constellation grabbed his attention (as mentioned in his 1573 book, ``De Nova Stella" (On the new star) ) . Tycho reports (from Burnham's Celestial Handbook): I was not ashamed to doubt the trustworthyness of my own eyes. I had no further doubts. A miracle indeed, one that has never been previously seen before our time, in any age since the beginning of the world. This remarkable discovery was important as it refuted the previously believed Aristotelian belief in an unchanging celestial realm. The instruments Brahe used for observing the night sky were mural instruments or sextants instruments which can only mark positions of the stars
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on the celestial sky. The discovery of refracting telescope by GermanDutch spectacle maker Hans Lippershey in 1608 created a revolution in the field of astronomy. The invention soon proliferated across the Europe and the scientists began making their own telescopes which led to a plethora of astrophysical discoveries. One of them was smart enough to make a telescope of magnifying capability that could see celestial bodies more distinctly than was ever possible before. Galileo Galilei built a telescope in 1609 and pointed it towards the sky and made stupendous discoveries, hitting the ball right out of the park. For the first time he observed hithertounknown objects in the heavens - spots on the Sun, craters on the Moon, the stars of the Milky Way, and in 1610 he observed the first four satellites of Jupiter- Io, Europa, Ganymede, and Callisto. Proving that not everything orbits Earth, he promoted the Copernican view of a Sun-centered universe (for which he obtained unpleasant reward from the Roman Catholic Inquisitionthe infamous story we all know).
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Space
From there on, every scientist tried to construct his own version of the telescope by improving the design of the previous one. Best of these instruments were constructed by the Christian Huygens of the Netherlands. Huygens discovered Saturn's ring and its largest satellite Titan in 1655. In 1781 amateur astronomer William Herschel discovered the planet Uranus. With the help of his sister, Herschel built over 400 telescopes during his lifetime which he used for observing the night sky. Henrietta Leavitt discovered more than 2000 variable stars called Cepheids between 1907 and 1921 while studying the photographic plates at Harvard to understand fundamental properties of the stars. The periodluminosity relationship of these peculiar set of stars which had their luminosity flux fluctuating periodically (hence variable stars) play crucial role in measuring distances to the other galaxies. Her work helped American astronomer Edwin Hubble to measure galaxy distances in the 1920s, which led to his realization that the universe is infact expanding. Maarten Schmidt in 1963 discovered the first quasar providing a probe of the universe back to substantial redshifts (or
time) while studying the spectrum of radio source 3C 273. He fathom the unfamiliar and perplexing emission lines in the spectrum of the source 3C 273 were the Hydrogen lines red shifted because the object was located billion of light years away. Such detections fall under the category of what is called direct imaging. The telescope is turned towards the sky and the object of interest becomes apparent in the images of the telescope. The object (star, structure or some signal) overwhelmingly stands out from the background (stars or noise) because of some kind of extraordinary physical property it possessesand its high signal strength and easily gets an attention. The only major effort lies is in building the instrument (telescope or spectrometer). The accidental discovery of CMB by Penzias and Wilson (1965) was an unintended detection of steady microwave signal which they initially took to be a very strong noise signal being detected by their receiver. However, this noise signal was 100 times stronger than they were otherwise expecting, which made them thinking that something mysterious was going on. Soon after talking with Prof. Bernard F. Burke about Jim Peebles paper
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on Universe's Blackbody radiation, Penzias and Wilson realised the significance of their discovery. Earlier, scientists used simple telescopes to explore the heavens. As the technology emerged and grew, experimentalists began pushing down the luminosity detection limit of the telescopes in order to observe more and more objects in the sky. Today we are well on our way to unravelling many of Universe's mystery, living in what maybe the most remarkable age of astronomical discoveries. Today, 400 years after Galileo, astronomers use giant mirrors on top of the remote mountains to survey the cosmos. Scientists have even launched telescopes into space, high above the disturbing effects of our atmosphere where the Universe is transparent and the view is breath taking. On 25 April 1990, a vision became a reality that was set forth by joint collaboration of European Space Agency (ESA) and National Aeronautics and Space Administration (NASA) together in 1970s of working together to design and build Hubble Space Telescope. The unprecedented deep images of the Abell cluster (cluster of galaxies) delivered by Hubble is
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Space
stunning. However, even after employing high tech new generation telescopes there always remain a large number of objects that go unnoticed in the images simply because of their low contrast or/and heavy background contamination or/and observational errors in the data making them difficult to be easily detected. For example, direct imaging of exoplanets is extremely difficult or in most cases impossible simply because being small and dim, planets are easily lost in the bright glare of giant stars they orbit. But that does not mean the planet is not there. In such cases, we just need to be clever enough to be able to detect such low contrast objects. Detections in such cases then require some sort ofdetection algorithm that can filter out the object of interest from the data. These detection algorithmsare mathematical models which are a convolution of the physical theory and some signal processing mechanism. The physical theory part helps in identifying the data points that behave in accordance to the phenomena we are interested in finding, while the signal processing part filters out the data points that follow the physical theory, hence revealing the structure. Clever
innovations lead to advancement of these techniques that then make it feasible to apply them in different and complicated scenarios to detect different kinds of astrophysical structures, objects, events or waveforms. These mathematical tools then require 3 conditions for a positive detection: ¡ The signal of interest is infact there in the data which is being analysed. ¡ The signal follows the predicted physical model/pattern. ¡ The signal of interest is above the detection limit. Detection limit depends on the signal strength, detection technique in work, precision of the data measurement and the level of contamination (unwanted background noise). There are different algorithms that exist in the literature today used for signal processing and structure detection. However Match Filters(MF) are widely used in the field of astrophysics - going from detection of clusters of galaxies to characterisation of light curves of stars with eclipsing exoplanets, extracting broad spectrum to detect supernovas,etc. Match filtering (originally developed by Wiener in 1949 for signal processing) is a template fitting technique used to extract
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the signal (object of interest) efficiently from the contamination (background or unwanted stars). It detects the signal of known shape by maximizing the signal to noise ratio (SNR) in the presence of additive stochastic noise. It does this by weighing the data points that follow the predicted model/pattern heavily which in turn increases the power of these desirable data points hence uncovering the hidden signal. For better detection of gravitational waves, the LIGO (Laser Interferometer Gravitational-wave Observatory) group used a form of Match Filter technique which was prepared based on the general relativistic models of the binary blackhole (BBH) merger waveforms using which they identified two signals GW150914 and GW151226.PyCBC and GstLAL were 2 different Match Filters made that used common waveform templatesbut differed in implementation. The MF was built to get a better quantified signal from the data. The GW signals are extremely weak signals immersed in an intense noise background. Pulling out a wave signal of such a low intensity from a dense background is only possible by using Match Filtering or some other signal processing technique.
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Space
Scientists often label new findings or new detections in terms of sigma. When Higgs boson was discovered in July 2012, scientists tossed around the phrase ``Its a 5-sigma detection" to describe the strength of the discovery. The probability of a value being measured while dealing with normal distribution depends on the mean (μ) and the standard deviation (σ). The further a measurement is from μ (i.e. towards either end of the bell curve, see Figure), the less and less likely it is of being measured at random, or due to a fluctuation in the background or just bychance. A 3σ detection event has a 0.3% probability of occurring by chance, and a 5σ event has just a 0.00006% probability of occurring by chance. Physicists traditionally call a 3σ detection ``evidence" (that they take as being the minimum to be believed), while a 5σ detection is considered a ``discovery" (which is essentially 0% probability of the result being false). If the model is good and data is of good quality, the s value is high too. Rene Descartes said When you do not have the power to follow the truth, follow what is most probable. “What happens if something that's really just part of the background
looks like a plausible signal?” That's exactly what the sigma tells you! The higher the sigma value, the less likely it is that a signal is just a random fluctuation in the background model. Another concept that is needed to be verified for scientific detections and discoveries is reproducibility. Just saying ``Aha! we have a detection" is not sufficient. In some sense it should be reproducible in order to convince people that infact the results are not any kind of artifact or a fake and the detected signal is not any kind of deceitfulness by the nature. The past few years have seen a slew of announcements of major discoveries in astrophysics such as detection of gravitational waves, detection of dark matter particles producing γ-rays, X-rays scattering off nuclei underground, and even evidence in the cosmic microwave background for gravitational waves caused by the rapid inflation of the early Universe. Some of these turned out to be false alarms and evidences for others are also inconspicuous (Not so for the Gravitational Wave detection atleast. The first detection in September 2016 was gold and the third one in January 2017 was platinum). There is nothing more deceptive than an obvious
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fact. Reproducibility means that the original data can be analyzed (by an independent investigator) using some technique to obtain the same results of the original study. Since the procedure followed to reproduce the scientific results is based on some full proof scientific theory, reproducibility also ensures that we understand the underlying science behind the phenomenon. In astrophysics, these scientific procedures are usually computer simulations which are used to revive the present day cosmological scenario and the structures within to check the validity of physical parameters in play. Many people seem to conflate the ideas of reproducible and correctness, but they are not the same thing. A study could be reproducible and still be wrong (the conclusion or claim can be wrong). If my claim has some value, then the correctness of the claim will be determined by whether others come to similar conclusions or not after they have attempted to reproduce my results. -Khyati Malhan, PhD Scholar, Strasbourg Universite de Strasbourg, 67000, Strasbourg, France
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RNI: 130379 UTT ENG/2013/57824