Preservatives from nature’s basket

In the increasingly popular category of natural cosmetics, staying true to nature and helping formulators deliver a natural-based product can be challenging when it comes to product preservation. To address this challenge, Sami-Sabinsa offers SabiLize-New – a truly natural preservative with proven efficacy.

Cosmetic products can easily become contaminated by bacteria and fungi, resulting in a spoiled product. Most cosmetics are made up of oil, water and other biodegradable ingredients, which present an optimum medium for the growth of microbes. This is why preservatives are vital to maintain the quality of a product and ensure its safe for use on skin.

The global cosmetics market is valued at around $460bn and is expected to reach $675bn by the end of 2020, accounting for 6.4% growth per year. Therefore, the increasing market requires continuous monitoring and multi dimensional control of toxic ingredients and microbial contamination 1.

Skin, the largest organ of the body, is constantly exposed to the environment and bears the brunt of invasion of pathogens, irritants and harsh chemicals 2. It also harbours symbiotic microbes, which provide protection from pathogenic or harmful organisms 3, 4.

Cosmetic products can become exposed to or are prone to microbial contamination during manufacturing (primary contamination) and/or during consumer use (secondary contamination) 5, 6. Therefore, it is very important to select effective preservatives, which prevent microbial contamination without altering the skin microbiome 7.

Two distinct groups of preservatives that are generally used to maintain the skin microbiome include, antimicrobial preservatives, which act on microorganisms, and antioxidant preservatives capable of suppressing oxidation phenomena and the formation of free radicals 8. In order to establish an effective inhibitory property, a preservative should have broad-spectrum activity and a longer shelf life than the cosmetic product itself 9 .

The most widely accepted and reliable method of preservation includes chemicals that are either synthesised from petroleum derivatives or are sourced from vegetable extracts, as well as those produced using natural substances or which are extracts with antimicrobial properties.

Compared to conventional synthetic preservatives, natural substances or extracts have received a great deal of attention in last few years because of their improved sustainability profile and safer nature 10.

Natural preservatives

These are ingredients from nature which are not chemically synthesized or artificially processed. They can be classified as anti-microbial, antioxidant and may have additional properties of preventing the ageing of cosmetics.

SabiLize ® -New, a patented proprietary product of Sami-Sabinsa, is a blend of natural antimicrobial actives with proven preservative efficacy. This product comprises essential oil fractions and extracts of monolaurin from Cocus nucifera, thyme oil from Thymus vulgaris and magnolol from Magnolia officinalis. At 0.5% concentration, SabiLize-New has shown to be significantly effective against strains of Staphylococcus aureus, Escherichia coli, Candida albicans and Aspergillus niger. The product also showed minimal ocular irritation and no irritation ofthe dermal layer.

It is very important to select effective preservatives, which prevent microbial contamination without altering the skin microbiome

Antioxidant agents

Free-radical scavenger molecules or antioxidants help in modulating the oxidation process (see Figure 1). Sabinsa offers a wide range of antioxidants:

• SabiLize-New shows excellent antioxidant activity with an ORAC value of 7394.58 ± 256.16 (μmol TE/g). Furthermore, the IC50 value of DPPH scavenging potential was found to be 54.07μg/ml.

• pTeroWhite ® , a natural 90% pterostilbene isolated from heartwood of Pterocarpus marsupium (Indian Kino), is clinically proven as a skin brightening and antiageing product. It is one of the few natural products evaluated for a natural sun protection factor (SPF) in humans.

• LactoSporin is also an antioxidant with free radical scavenging activity with an IC50 value of 0.43% v/v. These natural products are promising ingredients in maintaining healthy skin and efficiently enhancing the shelf life of cosmetics and personal care products. They are a healthier option when compared to synthetic products, as they are environmentally friendly and have a better safety profile. •

REFERENCES:

1. Halla, N., et al., Cosmetics Preservation: A Review on Present Strategies. Molecules, 2018. 23(7).

2. Farage, M.A., The Prevalence of Sensitive Skin. Frontiers in Medicine, 2019. 6(98).

3. Grice, E.A. and J.A. Segre, The skin microbiome. Nat Rev Microbiol, 2011. 9(4): p. 244-53.

4. Chen, Y.E., M.A. Fischbach, and Y. Belkaid, Skin microbiota-host interactions. Nature, 2018. 553(7689): p. 427-436.

5. Mitsui, T., New cosmetic science. 1997: Elsevier.

6. Pitt, T., et al., Bacillus cereus in personal care products: risk to consumers. International journal of cosmetic science, 2015. 37(2): p. 165-174.

7. Smith, C. and B. Alexander, The relative cytotoxicity of personal care preservative systems in Balb/C 3T3 clone A31 embryonic mouse cells and the effect of selected preservative systems upon the toxicity of a standard rinse-off formulation. Toxicology in vitro, 2005. 19(7): p. 963-969.

8. Martini, M.C., Conservateurs. In Cosmétologie et Dermatologie Esthétique. Vol. 1. 2006, Paris, France: Elsevier Masson.

9. Toler, J.C., Preservative stability and preservative systems. Int J Cosmet Sci, 1985. 7(4): p. 157-64.

10. Natural Preservatives: A Realistic Replacement? 2011 [cited 2020 16/05/2020] www.personalcaremagazine.com/story/7938/ natural-preservatives-a-realistic-replacement.

11. Goswami, D., et al., Boswellia serrata oleo-gum-resin and β-boswellic acid inhibits HSV-1 infection in vitro through modulation of NF-кB and p38 MAP kinase signaling. Phytomedicine: international journal of phyto-therapy and phytopharmacology, 2018. 51: p. 94-103.

12. Chouhan, S., K. Sharma, and S. Guleria, Antimicrobial Activity of Some Essential Oils-Present Status and Future Perspectives. Medicines (Basel, Switzerland), 2017. 4(3): p. 58.

Sabinsa – www.sabinsa.com

P C Review | JUNE 2020 | 33