Advance Magazine - Winter 2007/2008

Volume IV Number 1 Winter 2007/ 08

O F F I C I A L P U B L I C AT I O N O F T H E A D VA N C E D F O O D S A N D M AT E R I A L S N E T W O R K

The “full Nelson” treatment for fruit disease

Prof. Louise Nelson of the University of British Columbia has a new approach to preserving fruit in storage. See page 9.

INSIDE: Stressed bacteria are helping the food industry… page 8

PHOTOS COURTESY OF: "SDUJD/FU t $BOBEJBO *OTUJUVUF GPS 1IPUPOJD *OOPWBUJPOT t $BOBEJBO -BOHVBHF BOE -JUFSBDZ 3FTFBSDI /FUXPSL t $BOBEJBO 4USPLF /FUXPSL t *4*4 $BOBEB

Mobilizing Research Excellence, Creating Value Canada has 14 Networks of Centres of Excellence (NCE). Each network builds partnerships between academia, industry and government to put new knowledge, research and technology to work to create a better Canada. Their work touches everything from disease care and engineering, to improving the quality of the food we eat and the water we drink. NCEs are helping to keep our forests flourishing and ease the impact of climate change. By involving thousands of talented young Canadians in their work, they are training tomorrow’s scientific leaders and ensuring Canada’s continued role as a world science and technology leader.

The NCE Program supports thousands of researchers and highly qualified persons in dozens of Canadian universities. The program partners include Canadian companies, provincial and federal government departments, and agencies from Canada, along with international partners – making it a truly national and international program.

In 2006, the networks stimulated outside cash and in-kind investments totaling almost $70 million, including more than $27 million by the participating private sector companies.

With the program’s own investment, the total dedicated to research, commercialization and knowledge transfer was more than $149 million.

NCE PERSONNEL

NCE EXPENDITURES

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Networks of Centres of Excellence

54

694

868 79

56 159

1,337 2,408

www.nce.gc.ca

192 231

Ontario

42.2%

Québec

23.9%

British Columbia

11.5%

Alber ta

10.8%

Manitoba

5.0%

Newfoundland & Labrador

2.8%

Nova Scotia

2.4%

New Brunswick

1.2%

Saskatchewan

1.0%

Prince Edward Island

0.6%

Welcome The official publication of the Advanced Foods and Materials Network A publication to promote dialogue and understanding about sophisticated foods and materials research across Canada Executive Editors Rickey Yada Louise Jessup Project Co-ordinator Ashley McCarl

Editor Owen Roberts Associate Editor Kim Waalderbos Copy Editor Barbara Chance Design JnD Marketing Financial Manager Jan Smith Address correspondence to: Louise Jessup, Communications Manager 150 Research Lane, Suite 215 Guelph, Ontario, Canada N1G 4T2 E-mail: louise.jessup@afmnet.ca Visit the AFMNet website: www.afmnet.ca This publication was written by students in the SPARK program, Students Promoting Awareness of Research Knowledge, at the University of Guelph in Ontario, Canada.

Publications Mail Agreement Number 40064673 Please return undeliverable Canadian addresses to: AFMNet, University of Guelph, 150 Research Lane, Suite 215, Guelph, Ontario, Canada N1G 4T2

Dr. Murray McLaughlin

Project Manager Lilian Schaer

Welcome to our fourth annual edition of Advance, the official publication of the Advanced Foods and Materials Network (AFMNet).

For those of you who don’t know, AFMNet is Canada’s national food and biomaterials research network. Together, our researchers are presenting new ideas and developing new biology-based technologies to produce commercially viable, socially acceptable value-added products and processes that benefit all Canadians. Partnering with industry, government, not-for-profit organizations, and national and international research institutions, AFMNet has a vision for a healthier Canada.

On the pages that follow, you will read how AFMNet researchers are examining the GLUT2 gene to gain insight into its role in carbohydrate consumption and how this may affect diabetes risk; arranging gel pores into an interconnected network that will release chemicals more consistently to ensure an even release of medications; gathering protein- and geneexpression information to help regulators examine the composition and safety of genetically modified food products; and studying how able Canada’s regulatory system is to cope with genetic tests available to consumers and new claims that may be made about supplements, functional foods and nutraceuticals.

For the first time, you will also read about our Strategic Transition and Application of Research (STAR) Program projects. In times of rapid technological advancement and growing global competition, it is critical that new products and processes reach the market in a timely fashion. In February 2006, AFMNet introduced the STAR Program to fund research in emerging areas related to foods and biomaterials that benefit and are of relevance to the social and economic health of Canada. The program is characterized by a rigorous, industrially focused arm’s-length review and a rapid turnaround time, and is open to both AFMNet and nonAFMNet researchers, allowing us to capture untapped expertise with commercial relevance.

Our cover story, detailing the work of Louise Nelson, is one example. Using DNA-macroarray technology, Nelson and her team have developed a way to detect fungal pathogens while apples are still on the tree. They’ve also identified soil bacterial isolates that suppress the growth of these pathogens and are ready to commercialize the detection technology and soil bacterial isolates so they can be used on a larger scale. AFMNet is helping to make this possible.

We hope you enjoy this issue, encourage you to share it with others and, as always, welcome your feedback and ideas.

Dr. Rickey Yada

Volume IV Number 1 Winter 2007/08

Sincerely,

Rickey Yada Murray McLaughlin Scientific Director

Chair of the Board of Directors

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CONTRIBUTORS All contributors to Advance are part of the University of Guelph research writing program called Students Promoting Awareness of Research Knowledge (SPARK).

When researching this edition of Advance, SPARK writers found managing stress is vital for survival at many levels. For example, on page 8, they explain how bacteria take special measures to withstand harsh atmospheres.

Ashley McCarl

Fourth-year biological engineering student Ashley McCarl knows stress in both engineering and emotional terms. As co-ordinator of this year’s Advance magazine, she hits the gym to burn off any stress. In her article on probiotic yogurt, she explores how foods can be structured to improve health. See page 7.

Arthur Churchyard

In addition to his environmental studies, third-year arts and sciences student Arthur Churchyard keeps busy giving piano lessons and participating in student clubs. To manage his stress, he takes time to play with his feline family member, Simba.

Arthur’s interest in regulations surrounding new foods led to his story on page 13 about how Canada is coping with claims made about supplements, functional foods and nutraceuticals.

Kaitlyn Little

Kaitlyn Little, a third-year public management student, likes to immerse herself in books, newspapers and magazines to reduce her stress. In this Advance issue, she satisfied her curiosity about why consumers yearn for certain foods with her article on a gene that could increase cravings for carbohydrates.Turn to page 11.

Sarah Van Engelen

So, how do SPARK writers manage stress? Read on...

Fifth-year agricultural sciences student Sarah Van Engelen releases her stress by whipping up cakes in the kitchen or sitting down to needlework. In this edition, Sarah discovered that even under stress, bacteria’s ability to survive humans’ best cleaning efforts is actually helping the pharmaceutical industry. Find her story on page 8.

Photos by Olivia Brown

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CONTENTS

Strategic Transition and Application of Research

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Cookies made with fat that’s good for the heart

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Probiotic yogurt plays part in fighting ill effects of AIDS

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Bacterial resilience is helping the food chain

8

New storage treatments to prevent rot in apples

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Foods and Health

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Research looks at fibre and its impact on the human gut

10

Linking higher carbohydrates and consumption patterns

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Innovative model links breast milk and intestinal health

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Consumer and Ethical Issues Transgenic and conventional pigs compared for first time

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Canadian regulations may be unprepared for novel foods

13

Materials

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How to make peptides more economically feasible

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Natural and synthetic gels get set for use in food, medicine

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Cover photo by Tim Swanky

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Strategic Transition and Application of Research Martin Schwalbe

Cookies made with fat that’s good for the heart Researcher develops healthy solid fat for industry baking needs

By Ashley McCarl

Humans may be at their weakest point in the checkout line at the grocery store.

Amid the gossip magazines, batteries and chewing gum lurks a calorie counter’s nightmare: racks of chocolate bars. There can’t be much harm in one little chocolate bar, can there? And isn’t there research saying chocolate is good for you?

The answer to both questions is yes and no. In moderation, sweets can be part of a balanced diet. And, yes, chocolate can be good for you, especially dark chocolate with its antioxidant properties. But foods with large amounts of trans fat and saturated fat are harmful, even in small quantities.

And that’s what a lot of popular snacks contain.

But all is not lost for checkout-line junkies.

Prof. Alejandro Marangoni of the University of Guelph’s Department of Food Science sits back as he recounts seeing a Twix Bar production line running smoothly with his newly developed fat — one that contains no trans fat and is low in saturated fat, making it healthy for consumers. He saw it being tested on a line in Germany, home to some of the world’s best chocolate.

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“Now, that’s cool,” he says.

In response to strong consumer demand for healthier foods, companies worldwide are reducing or eliminating trans fats in many of their products. Doing so has been a huge challenge for the food industry, which relies on solid fats such as trans fats to maintain the texture, consistency and structural properties of baked products.

To reduce trans fats, many food companies turned to palm oil as the easiest alternative to meet their needs. Palm oil (or palm fat as it’s called in Canada) is made from palm tree fruit and is a popular substitute because it’s cheap, is widely available and because it stays solid at room temperature in North American climates. Most importantly, palm fat doesn’t contain trans fats. But it’s very high in saturated fat, which is also harmful.

“Trans fats are a public health concern, and now we’ve come up with a healthier alternative,” says Marangoni.

To make the new product, he first looked to the structure of trans fats. He knew they formed a crystal structure at room tem-

Cookies are taking a turn for the better healthwise, thanks to a new processing fat created by Prof. Alejandro Marangoni of the University of Guelph.

perature, which created the necessary building blocks to form the solid fat structure. He also knew trans fats were cheap to manufacture and increased the shelf life of the final product. Any new fat Marangoni developed would have to keep pace with those properties yet contain less saturated fat.

He began with standard oils — canola and soybean — because they were produced locally, making them easily available. The challenge was to make the oils solidify at room temperature. Part of the solution, he found, was already widely used in other areas of the food industry.

Emulsifiers such as egg yolk are commonly used in food products to mix together two substances that wouldn’t otherwise combine. He was able to use a particular emulsifier with his oil and water mixtures to make the liquids combine, solidify and produce a fat-like material.

Marangoni explains how it works: The emulsifier encircles the oil molecules, forming small droplets. The droplets crystallize and bind to each other to produce a solid structure that is very similar to the structure of bread and foams.

Even though the material looks like a fat, its structure is much different from that of the traditional fat crystal network, he says. The material works extremely well as a bakery shortening and, according to food regulations, should be referred to either as a light margarine or a shortening alternative.

But the research didn’t stop there.

Marangoni quickly learned that his novel material couldn’t be substituted for conventional fat sources at a one-to-one ratio in many food products. So he set out to determine how much of the new shortening alternative was needed to produce the same taste, texture and consistency characteristics provided by other fat sources.

He has hired three recent University of Guelph graduates to work with his shortening alternative in typical baking applications to find the substitution ratios for each use. They’re finding that the new shortening alternative does a great job in cookies and creates a flaky pie crust.

They’ve also discovered that the new fat can make batters somewhat “stickier,” which is especially useful for baking cookies that contain chocolate chips. Marangoni says the new material reduces the number of chocolate chips needed by 40 per cent because fewer chips break or fall off on the assembly line.

“And that can save a company millions of dollars,” he adds.

Excitement is high as the product is put through its final marketing and commercialization test phases. With a patent pending, Marangoni expects his low-saturated-fat product will be available commercially later this year.

If it passes shelf-life testing, the fat will hit the market sooner in cookies and chocolate bars.

The Guelph food scientist worked in collaboration with physics professor Stefan Idziak of the University of Waterloo. Graduates working on this project are Sarah Langmaid, Brittany Huschka and Carolyn Challacombe. This research is supported by AFMNet, and commercialization is led by Steve Bernet of Coagel Corporation.

Probiotic yogurt: A tool for fighting ill effects of AIDS

By Ashley McCarl Elena Elisseeva

Probiotic yogurt is now being used to help lessen side effects for Yogurt has long AIDS patients in Africa, thanks to a Canadian researcher. been touted for its Prof. Gregor Reid of the Department of Microbiology and health benefits.

Immunology at the University of Western Ontario (UWO), took part Now, research at in UWO’s inaugural mission to address the AIDS crisis in Africa in the University of 2003. When the students on the mission were in need of a project Western Ontario that would benefit their community of interest, Mwanza, Tanzania, is proving this and Reid thought of tying in his probiotic work. more as yogurt is Probiotics are specific bacteria that in some cases can be added to eyed as part of a foods to enhance immunity and reduce the duration of illnesses such treatment plan for as diarrhea. Research by Reid and Prof. Shari Hekmat of Brescia people with AIDS. University College at UWO had found their probiotic yogurt has immune-modulating properties. They wondered if the same properties would have an effect on other conditions, including chronic diarrhea in people with HIV/AIDS. “The team has shown that local mothers in Tanzania can be taught to make probiotic yogurt, and some data show good health benefits from daily consumption,” says Reid.

Studies performed by UWO post-doctoral fellow Kingsley Anukam in Nigeria showed that regular yogurt supplemented with Reid’s probiotic lactobacilli could improve immunity and cure diarrhea. Meanwhile, in Tanzania, when the locally produced probiotic yogurt was consumed daily, it led to increased energy and fewer ill effects in people with AIDS. Four years after the program began, the yogurt has become part of the supplementary care given to more than 80 AIDS patients in Mwanza. Interns from UWO arrive in the community three times a year to continue research and bring back messages to educate the UWO community.

The locally made probiotic yogurt has become widely popular in Tanzania and has had such a high success rate that the World Bank — a group dedicated to eradicating world poverty — has decided to expand the project to Kenya.

Reid is now working with his UWO colleagues to create a probiotic yogurt that can be given to people with other diseases linked to immune suppression. Graduate student Jamie Hemsworth and high school student Raj Bhayana, recipient of a Sanofi Aventis Biotech Challenge award, have helped develop specific nutrient formulas for the yogurt and are about to begin human testing.

“If the trial shows promising findings, this food could be a great addition to current treatments and improve lives around the globe,” says Reid.

Funding is provided by AFMNet, the Canadian Institutes of Health Research, the Lawson Health Research Institute, the Natural Sciences and Engineering Research Council and the Ontario Ministry of Agriculture, Food and Rural Affairs.

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Strategic Transition and Application of Research

Benefiting from bacterial biofilms Novel products from micro-organisms could aid in drug delivery, producing car parts... and more

By Sarah Van Engelen Olivia Brown

When scientists in physics and microbiology teamed up to study how bacteria grow on surfaces and protect themselves from external influences, one of their areas of focus was identifying components and products of the bacteria that could be used in developing novel products. As time goes on, that focus is getting clearer.

It was University of Guelph physicist John Dutcher and the late Terry Beveridge, a renowned Guelph microbiologist who passed away this fall, who had immersed themselves in studying how bacteria live, multiply and function on different surfaces in various environmental conditions. Bacteria form communities called biofilms on almost any surface, and now Dutcher is carrying on with the research, exploring the components and products of biofilms for use in other applications to benefit humans.

“Bacteria are highly evolved and sophisticated,” he says. “We need to take advantage of their resiliency.”

Learning how bacteria grow and form colonies on surfaces such as counters, filing cabinets and food materials is only half the process. Studying how they stick to surfaces and how they produce a biofilm is another major part of understanding how bacterial resiliency can be used. Despite being stressed from antimicrobial agents and scrubbed from surfaces, many bacteria are able to survive humans’ best eradication efforts.

To Dutcher, that’s what makes their properties so interesting.

One material of particular interest is the stiff, strong mesh of small proteins and sugars that encloses the bacterial cell. This matrix allows the cell to withstand harsh atmospheres and large differences in pressure. Dutcher is trying to understand the structure and improve the purification process of this biomaterial.

“It’s often very difficult to make an artificial material that is better than something produced naturally,” he says, “so we want to make use of the special properties of the components of biofilms.”

The ultimate goal is to use these components in novel ways such as incorporating them into car parts, medical tubing and pharmaceutical encapsulates, says Dutcher, who believes many opportunities are possible.

Another option is to extract the unique biological mesh material from the cells and incorporate it into other materials to achieve improved strength and mechanical properties for use in car parts or medical tubing, he says.

“The applications for biofilms are limited only by your imagination.”

This project involves a large number of AFMNet researchers: 10 different groups with 24 students and postdoctoral researchers. Funding is provided by AFMNet, the Canada Research Chairs program, the Canada Foundation for Innovation and the Natural Sciences and Engineering Research Council.

Physics professor John Dutcher takes a break from his lab, where he’s exploring the components and products of biofilms for use in applications that will benefit humans.

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Tim Swanky

Rot not Environmentally friendly storage effectively beats fungal pathogens

By Kaitlyn Little When apples in the orchard pick up fungal pathogens, there’s trouble down the line. When the fruit is placed in cold storage for at least six months, the pathogens cause the apples to rot. It’s a real problem: fungal rot results in crop losses of five to 10 per cent each year. Fungicides can be used to control this problem, but they’re falling out of favour. So now, researchers are taking a new approach.

Prof. Louise Nelson of the University of British Columbia and Peter Sholberg of Agriculture and Agri-Food Canada’s Pacific AgriFood Research Centre have developed a way to detect fungal pathogens while the apples are on the tree. They’re part of a team that has also identified environmentally sustainable soil bacterial isolates that act as effective biological control agents against the fungal pathogen.

“There is greater demand for environmentally sustainable postharvest treatments to counter health concerns from the public as well as to meet the needs of an emerging organic market,” says Nelson.

The pathogens that cause the post-harvest decay in apples are blue mould, grey mould and Mucor. Detecting these pathogens

University of British Columbia researchers (left to right) Daylin Mantyka, Prof. Louise Nelson and Danielle Hirkala evaluate whether fungus has affected apples that have come out of cold storage. before the apples go into storage means producers can limit postharvest rot by keeping the affected apples out, she says.

The research team developed a DNA-based macroarray technology that detects all three fungal pathogens and allows users to go into the orchards and check for incidence of disease.

Here’s how it works. Samples are taken from leaves, blossoms and air, then analyzed to determine if the three pathogens are present. Using DNA macroarray technology, Nelson can pinpoint the relationship between high levels of pathogens present in the air, leaves and blossoms and the presence of post-harvest decay during storage.

In cases where storage is needed for apples that have been exposed to the pathogen, the research team has developed an organic solution — they’ve identified soil bacterial isolates that suppress the growth of all three pathogens. Before the apples go into storage, they’re dipped into solutions containing the isolates to protect them from post-harvest decay. By the time the apples come out of cold storage months later, the soil isolates decrease to a minimal level on the apples. Treating the apples this way eliminates the need for fungicides and eases consumer health concerns.

Now, Nelson and Sholberg hope to commercialize the DNA macroarray technology and the soil bacterial isolates, so they can be used on a larger scale.

“This research will be relevant across the country as it can eliminate the negative effects of moulds in orchards as well as in other fruits that are susceptible to the pathogens,” says Nelson.

Also involved in this project is post-doctoral researcher Danielle Hirkala.

This research is sponsored by AFMNet and Western Economic Diversification Canada.

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Foods and Health

Gut check Researchers look to digestive-tract bacteria for greater understanding

Brian Fray

By Kaitlyn Little

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What you eat has a significant effect on the bacterial community in the intestine, or gut.

Although it’s widely accepted that fibre is an important part of a healthy diet, it’s still unclear how fibrous foods, particularly those with wheat and oat bran, specifically contribute to intestinal health.

Prof. Brent Selinger of the University of Lethbridge and Prof. Martin Kalmokoff of Dalhousie University are examining the role of dietary fibre and prebiotics (carbohydrate polymers) in gut bacteria and their link to gut health.

The scientists are delving into unknown research territory to understand the gut-associated bacterial community and how diet affects it. The intestinal community contains more than 400 species of bacteria, but only about 10 per cent have been well-studied to date. The vast majority have not been previously isolated or characterized in terms of their metabolic activities.

But now, Selinger and Kalmokoff are working at a molecular level by using BioBreeding rats (bred and reared in an inbred colony) to tease out how the bacterial community is structured, how it changes in response to different dietary fibre sources and how this affects the immune state of this animal model. This model offers the advantage of a relatively stable bacterial colony passed from mother to offspring.

“Understanding how dietary factors change the gut community may allow us to design functional foods that may manipulate these complex microbial communities and result in improved health for the host,” says Kalmokoff.

The gut is host to trillions of bacteria that may play a crucial

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role in host immune function, resistance to infection and nutrient processing. The bacteria provide nutrition to the cells lining the intestine through the production of short-chain fatty acids, by fermenting dietary material entering the intestine. This complex bacterial community appears to interact significantly with the body’s immune system, which may have a major effect on physiological health.

In the fibre study, the BioBreeding rats were fed various dietary fibres, including wheat bran, oat bran and prebiotics. The rats were then examined to see what impact the dietary fibre had on the bacterial populations in their gut and on the immune state of the host. The researchers have found significant differences in colonic bacterial viability depending on the dietary fibre source and changes in specific bacterial strains in response to fructans (sugars).

The knowledge gained by these studies helps support regulatory decisions at Health Canada, providing evidence to help evaluate the efficacy claims associated with fermentable carbohydrates and prebiotics. The trials with prebiotics also help the scientists understand their contribution to gut health. Once all the data have been gathered on the response of bacterial intestinal communities to various fibres and prebiotics, the researchers hope the knowledge will help consumers make informed fibre choices.

“Dietary fibre is an important component of a healthy lifestyle,” says Selinger. “This research will allow us to guide consumers to buy high-quality sources of this fibre.”

Other members of the research team include Prof. Julia Green-Johnson of the University of Ontario Institute of Technology, Dr. Stephen Brooks and Dr. John Austin of Health Canada, Prof. Doug Inglis of the University of Lethbridge and Prof. Lisbeth Truelstrup-Hansen of Dalhousie University.

This project is sponsored by AFMNet, Agriculture and Agri-Food Canada, and Health Canada.

Breast milk for gastrointestinal health

By Arthur Churchyard

Gabriela Trojanowska

Here’s more evidence to bolster the breast-is-best argument: a University of Manitoba researcher says mother’s milk has a powerful ability to improve gastrointestinal health.

Prof. William Diehl-Jones, Faculty of Science, has built a model to mimic the inner conditions of an infant’s digestive tract. The model combines a digestion process similar to that occurring in the infant gut and a cell culture system that’s like the innermost layer of the intestinal tract. It shows that compounds in breast milk protect and nourish tissues of the intestine by preventing damage from oxidative stress (where molecules interfere with normal cell functions), a problem commonly encountered by premature infants.

Diehl-Jones developed the infant gastrointestinal model to determine how breast milk compounds are absorbed by and protect digestive organs from damage.

Now he’s working with collaborators to determine which specific compounds are most effective. He hopes they will ultimately be used to improve foods such as baby formula.

“We can learn from nature to create smarter foods and treatments for infants,” he says. “As we isolate breast milk compounds that improve intestinal and overall health, we gain the ability to add health benefits to formula.”

The model is one part of a crossCanada study linking biochemists, physiologists and nutritional scientists who are delving into what compounds make breast milk best.

Breast milk diminishes the levels of free radicals (highly reactive molecules) in the digestive tract and reduces damage to DNA, lipids and proteins in mucosal cells, which line the gastrointestinal tract. These free radicals can cause an imbalance in the body that has been linked to premature infant diseases such as necrotizing enterocolitis (an inflammatory bowel disorder) and a condition called retinopathy of prematurity, which causes visual impairment and even blindness in infants.

Diehl-Jones and his collaborators also plan to determine the extent to which antioxidant molecules are absorbed into the infant’s circulatory system, which could give additional benefits to the pre-term infant.

He is part of a team working with University of Manitoba human nutritional sciences professor James Friel to isolate the most beneficial breast milk compounds, The isolated compounds hold potential for infant formula, but future studies will establish whether the breast milk compounds that protect the pre-term infant from oxidative stress could do the same in adult diets.

This work contributes to a multidisciplinary breast milk partnership that includes University of Manitoba professors Rotimi Aluko, Miyoung Suh and Trust Beta of the Department of Human Nutritional Sciences, as well as Prof.

David Kitts of the University of British Columbia and Jean-Claude Lavoie of the Centre hospitalier universitaire SainteJustine in Montreal.

Babies who consume breast milk are getting more health benefits than previously thought, according to new research.

Linking higher carbs and consumption patterns

By Kaitlyn Little Researchers at the University of Toronto have found that a gene dubbed GLUT2 may have a bearing on increased carbohydrate consumption.

Prof. Ahmed El-Sohemy and master’s student Karen Eny of the Department of Nutritional Sciences discovered that people with a genetic variation in the GLUT2 gene consume larger amounts of carbohydrates.

“Previous studies linking the GLUT2 gene with diabetes have been inconsistent,” says Eny. “Now we’re examining whether environmental factors such as carbohydrate consumption are also associated with this gene, which may partly explain the inconsistencies in previous gene-disease association studies.”

In the study, two populations are being examined: one group that’s been diagnosed with diabetes and a second group of young, healthy subjects. Members of the diabetic group kept a record of their food intake for three days to determine their carbohydrate consumption. The second group completed a one-month food-frequency questionnaire to assess their consumption of a variety of foods.

All participants had their DNA isolated to learn if they carry the genetic variation in the GLUT2 gene.

It’s hoped the study’s findings will provide insight into the role this gene plays in carbohydrate consumption and how this may affect diabetes risk.

“We hope this approach, which considers both environmental and genetic factors, will help in designing and conducting genetic diabetes risk association studies in the future,” says Eny. Other collaborators involved in this study are University of Toronto professor Thomas Wolever and graduate student Bénédicte Fontaine-Bisson.

Funding for this project is provided by AFMNet, the Canadian Institutes of Health Research and the Natural Sciences and Engineering Research Council. Eny also received the Julie Payette Research Scholarship.

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Consumer and Ethical Issues

Comparing transgenic and conventional organisms:

A new approach

By Matt Teeter

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Two teams at Guelph and McGill are at work on porcine and soybean projects, each with the goal of creating a database of gene expression or the combination of gene expression and proteins that can be used by regulators when examining future food products.

The first team is examining protein expression in the major food tissues of conventional and transgenic pigs. The second team is looking at changes in gene expression between conventional and transgenic soybeans under different environmental conditions.

Much of the raw data have now been collected, leaving the researchers to work on data processing and interpretation, creating the databases for use by regulators, scientists and others interested in these areas, including bioinformation and biotechnology companies. When the work is completed, regulators could use the databases to assess the composition and safety of new food products.

Team members on this project include Profs. Serguei Golovan and David Chiu, technician Roy Meidinger, post-doctoral researcher Hatam Hakimov and graduate student Moshe Gadish of the University of Guelph, and Profs.

Marc Fortin and Martina Stromvik of McGill.

This research is sponsored by AFMNet, industry partners and le Fonds québécois de la recherché sur la nature et les technologies.

Cecil Forsberg

The safety of foods made from genetically modified organisms can be better evaluated with information about differences in gene expression and protein production, say researchers at the University of Guelph and McGill University.

They believe that, along with data such as the carbohydrate, protein and fat content of foods, protein- and gene-expression information would help regulators examining the composition and safety of genetically modified food products.

The data currently used by regulators are limited, says Guelph professor Cecil Forsberg, Department of Molecular and Cellular Biology. That’s why a research group at Guelph is examining gene expression and proteins to provide a molecular picture that will expand the detail of information available to regulators.

Forsberg, co-inventor of the transgenic Enviropig, which better uses dietary phosphorus, is working with colleagues to compare conventional pigs with their transgenic counterparts. Much testing is required before these animals can be introduced into the food chain.

He says any variation between the two could signal a potential health risk for humans. And although it’s early, no significant differences have been found so far.

“We haven’t found any physiological differences to keep us from moving ahead with the transgenic pigs.”

The Enviropig created at the University of Guelph is being measured against its conventional counterpart at the genetic level to determine if differences exist in protein production.

Unprepared for change Delays could deprive Canadians of nutrigenomics benefits

By Arthur Churchyard

Shoppers in health food stores face a sometimes confusing array of options.

Researchers are looking into Canadian health food guidelines to help protect consumers.

Martin Schwalbe

The fledgling science of nutrigenomics — the study of how nutrients and genes interact — may raise issues that catch the Canadian regulatory system off guard, says a University of Ottawa researcher.

Prof. David Castle, Canada Research Chair in Science and Society, is studying how well Canada’s regulatory system would be able to cope with new ways genetic tests may be provided to consumers and new claims that may be made about supplements, functional foods and nutraceuticals.

“Our concern is that nutrigenomics will raise new issues for regulators,” says Castle, “and we’re not confident that the Canadian regulatory system, as it stands, can address all of these issues.”

He points to the United Kingdom as an example of why Canadian regulators should be proactive in preparing for new social issues raised through advances in nutrigenomics. In 2001, U.K. consumer associations campaigned to express fears about a genetic test that hit the market after clearing what they believed were inadequate regulations. Because of this perceived gap in the regulatory system, the company with the genetic test was forced to stop selling directly to consumers, regardless of whether the product offered legitimate benefits.

The benefits of nutrigenomics — and the harm of potentially misleading advice or unfounded claims about nutrigenomic products — need to be better measured and understood by regulators, says Castle, who is incorporating what’s been learned from the United Kingdom and other countries into his Canadian-focused study.

Nutrigenomics has received international attention because of its potential to capitalize on interactions between people’s genes and the foods or supplements they consume, he says. It allows genetic tests to be developed that can predict whether an individual is predisposed to certain diseases.

Theoretically, it also means that diseasecausing genes could be inactivated through biological changes evoked by certain nutrients, or that disease-fighting genes could be activated.

But the complexity surrounding nutrigenomics has elicited varied reactions from researchers, biotech companies and government.

That’s why Castle is studying print media articles used by these stakeholders to understand differences in how each group portrays nutrigenomics.

In another part of his study, a series of focus groups held in partnership with the Public Health Agency of Canada will assess the understanding of the public and health-care practitioners about nutrigenomics. The focus groups will reveal how much Canadians already know about nutrigenomics, while tracking opinion shifts that occur as groups become more informed.

When his study wraps up in 2009, Castle will offer recommendations on how Canadian regulations could be adapted to better address genetic tests and their distribution, as well as health claims about supplements, functional foods and nutraceuticals.

“We aren’t talking about creating new regulations,” he says. “Instead, we’re asking how comprehensive our current regulations are and if they can be improved.”

Legal analysis for the study is being conducted by University of Alberta professors Tim Caulfield and Nola Ries of the School of Public Health and Faculty of Law and Tania Bubela of the Department of Marketing, Business Economics and Law. University of Ottawa collaborators include Prof. Karine Morin and students Sarah Scott and Juliana Aiken of the Department of Philosophy.

This research is part of Genome Canada’s Genomics, Ethics, Environment, Economics, Law and Society initiative. Funding is provided

by AFMNet. AFMNet – ADVANCE 2007/ 08

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Materials

Keeping it short

Andrei Tchernov

The simple DNA of Arabidopsis, such as the one pictured here, promotes the species use in genetic trials. Researchers at the University of British Columbia are using these plants to produce peptides, a potential new bacteria-fighting agent.

Researchers find ways to make peptides more feasible for food use

By Ashley McCarl Peptides — short chains of amino acids — are effective at providing protection from harmful bacteria by attacking the bacterial cell and interfering with vital functions. Medical practitioners are running clinical trials to study how peptides might be administered to patients in place of antibiotics to help cure bacterial infections. Now, members of the food sector hope to also use peptides in consumer products to improve food safety. But before this can happen, peptides need to be more economically feasible.

To that end, Prof. Robert Hancock of the Department of Microbiology and Immunology at the University of British Columbia has been studying three different ways to reduce the cost of peptides. He’s drawing on his 20-year knowledge of what he calls “the small molecule with huge potential,” having worked with the two smallest known natural peptides: bovine bactenecin and bovine indolicidin.

“These peptides can easily be used in the food-service sector,” says Hancock, “but they need to cost mere pennies to be feasible, and therein lies the challenge.”

In the first approach, his research focus is on the length of the peptide chain. He hopes to

Bob Hancock

University of British Columbia researcher Bob Hancock is developing three different ways to produce peptides, which could be used in food and food packaging to boost consumer safety.

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shorten the peptide to save money by reducing materials (amino acids), production and time.

Traditional methods of producing the peptides in the laboratory are labour- and time-intensive and result in a single peptide costing more than $600. Using the 20 amino acids as building blocks and a peptide array robot could greatly reduce the scale of peptide synthesis and cut the cost to less than a dollar per peptide, he says.

“The robot allows us to explore a much broader range of possibilities because the peptides are so much more economical.”

Using the robot, Hancock’s team has been able to assemble peptides of eight to 12 amino acids in length that are just as potent as the normal 18-amino-acid-length peptides. Catalogues of the peptides the team has created are recorded in a database with details about their genetic makeup and effectiveness at protecting against bacterial infection. The list is now extensive enough that the researchers can predict what peptide chain sequences will be most efficient with 90-per-cent accuracy, saving time and money.

In the second approach, Hancock is part of an investigation into using lactic acid bacteria to create peptides. Once a particular peptide is isolated, large batches of the bacteria are used to produce the peptide on a larger scale at low cost.

The third approach involves synthesizing peptides using potato plants and Arabidopsis, a plant from the mustard family commonly used in genetic studies. The researchers hope to use the plants in two ways to produce peptides. In the first, genes for the peptide are transferred into a plant, which acts as a factory to synthesize peptides that are later harvested (analogous to the bacterial production method). The second method modifies the plant to produce lower peptide levels for self-protection, which are then transferred to food products created with the plant material.

Ultimately, finding economical ways to produce peptides will make their incorporation into food products more feasible, says Hancock.

“If peptides can easily be placed in both the food and food packaging, and at low cost, they will protect the consumer from the many foodborne bacterial contaminants that can make us sick today.”

Also involved in this research are Prof. John Vederas of the University of Alberta and Prof.

Santosh Misra of the University of Victoria.

Materials

Research that gels Biopolymers find use in food and medicine

By Matt Teeter Biopolymers — natural and synthetic materials that are made of repetitive molecular structures — have lots of promise for tissue regeneration, food preservation and antimicrobial agent delivery. But what’s the best way to make them work? That’s the challenge facing AFMNet researchers developing new biopolymers or “gels” that are capable of releasing embedded beneficial compounds over time.

Making microstructured gels can be difficult and often requires special equipment, says Prof. Dérick Rousseau of the School of Nutrition at Ryerson University.

He thought there should be a better way, so he took a back-to-basics approach to biopolymer manufacturing.

“We asked: ‘Can we make gels using basic things we already have in the lab?’

The answer was: ‘Yes, easily and with very good results.’”

With nothing more than a microscope slide, biopolymer solutions and standard laboratory equipment such as a centrifuge to spin and separate the components, Rousseau was able to generate thin films of gel without difficulty. He can saturate the

film with a compound, creating a slowrelease biopolymer that has a wide range of applications. Now he’s teamed with researchers across the country to put the gels into action.

It’s the pores within gels that hold the chemicals to be released. But when most gels are made, these pores are arranged randomly. As the gel dissolves, this randomness often means the chemicals aren’t released uniformly, which is a big problem if the gel is holding medication that requires an even release.

So Rousseau is collaborating with researchers at Dalhousie University who are developing a process to arrange the pores into an interconnected network that will release chemicals more consistently.

One application of these gels is the controlled release of antimicrobial agents.

Network researchers at Dalhousie and Agriculture and Agri-Food Canada are investigating the use of gels containing antimicrobials derived from natural food sources.

“It’s amazing how many compounds naturally have antimicrobial properties,”

he says. “Many are everyday food items like vanilla and rosemary, and we’re incorporating their benefits into these gels.”

One promising gel uses allyl isothiocyanate, a broad-spectrum antimicrobial found in mustard. The gel will be tested in chickens to eliminate harmful gut bacteria.

This mix of basic and applied science is a big benefit to the biopolymer research program, says Rousseau.

“One of our greatest strengths is research diversity. Our researchers span the country and all themes of AFMNet.” The other researchers leading these projects are Profs. Allan Paulson, Amyl Ghanem and Lisbeth Truelstrup-Hansen of Dalhousie, Prof. David Pink of St. Francis Xavier University, Prof. Molly Shoichet of the University of Toronto, Prof. Wankei Wan of the University of Western Ontario, Prof. Brian Amsden of Queen’s University and Pascal Delaquis of Agriculture and Agri-Food Canada.

This research is funded by AFMNet.

Brandon Denard

Figure 2

Figure 1 Holes in the gels produced by bacteria are not evenly spaced, as seen in Figure 1.

Researchers are trying to manipulate the structure to be evenly spaced, as seen in Figure 2, so these gels can be used to release chemicals in pharmaceutical or food applications in a more uniform way.

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