Over the last few years, the interest about the role of microbiota and its role on skin has been arising. The idea of restoring the perfect balance of microorganisms for obtaining benefits on skin health will probably be a building block for the present and the future Beauty Era [1].
According to this trend, fermented ingredients are increasingly breaching in the cosmetic market. Among these, Kombucha is getting just recently more popularity, even though it has ancient roots [2,3].
Fig.1 Kombucha is becoming more and more a popular drink.
Kombucha is a beverage obtained from tea fermentation (usually black tea) with sugar and SCOBY, a Symbiotic Culture Of Bacteria and Yeast [4].
This mixed culture includes acetic acid bacteria (AAB, ex. Acetobacter) species, lactic acid bacteria (ex. LAB as Lactobacillus) and yeasts (ex. Saccharomyces cerevisiae), that during fermentation create a floating biofilm on the surface of the liquid phase (growth medium). This symbiosis should also inhibit dangerous contaminating bacteria [5].
Fig. 2 Floating biofilm on the liquid phase.
Kombucha combines three different fermentations: alcoholic, acetic and lactic fermentation.
Due to the fermentation process, different organic acids, contributing to the peculiar acidic, fizzy, unique taste, are present: acetic, glucuronic, lactic, tartaric, and malic. Even if in smaller amount, citric acid is also present.
Moreover, amino acids, vitamins (mainly group B), minerals (Cu, Fe, Mn, Ni, Zn), polyphenols (as flavonoids) and enzymes (invertases) are also contained in this fermented drink [6,7].
Thereby, kombucha is enriched with high content of active substances and probiotics, which may exert a positive effect on general health [7].
Fig. 3 Main metabolic activity of kombucha tea (Markov et al., 2003).
So far, the interest has always been around kombucha oral intake, where several studies are still investigating various health effects as prevention of cancer and cardiovascular diseases, anti-inflammatory, antidiabetic, hepatoprotective and immunomodulatory [7,8].
However, many cosmetic brands are starting to use kombucha as a key ingredient of their products and it will probably be a training trend of 2022: but what is the science behind that?
One in vitro study in 2021 measured the antioxidant properties of this fermented tea on free radicals, along with its abilities of inhibiting collagenases and elastases. These are enzymes in the skin, responsible for the degradation of collagen and elastin, two structural proteins present in high percentage in the dermis that are fundamental in young and healthy skin for guaranteeing firmness and elasticity but decrease with ageing [9,10,11].
Kombucha showed to reduce the level of free radicals in skin cell types, specifically keratinocytes and fibroblasts, acting as antioxidant. Moreover, it also increased the viability of fibroblasts, cells responsible for collagen and extracellular matrix synthesis, ameliorating their metabolic activity. In the end, the inhibition of matrix metallopeptidases, enzymes that literally destroy our proteins in the ECM, leading to skin ageing, was demonstrated as inhibition of collagenase and elastase enzymes, which is probably due to phenolic compounds. In addition, it seems that the fermentation time is an important factor to consider for the final number of active substances in the product [11].
Regarding in vivo studies, kombucha, applied topically, seems to help skin ageing and skin microrelief [12,13].
Another study showed that intradermal administration in mice ameliorated the connective tissue abnormalities in aged skin (increased collagen content) and stimulated NAD+ / NADH level, symbol of energy production.
Moreover, antioxidant and anti-inflammatory properties and absence of skin sensitization was shown [14].
All these studies suggest that Kombucha may be a valuable cosmetic ingredient to use, however more studies are necessary to confirm the validity and clarify the toxicity and safety aspects of this natural substance.
If you are curious about how Kombucha is prepared, here’s a hint! https://www.bbcgoodfood.com/howto/guide/how-make-kombucha
And if you are interested in microbiota and skincare, read one of our articles:
https://www.emotion-master-studentproject.eu/post/skincare-microbiota-and-you
References
1. Gueniche A, Perin O, Bouslimani A, et al. Advances in Microbiome-Derived Solutions and Methodologies Are Founding a New Era in Skin Health and Care. Pathogens. 2022;11(2):121. Published 2022 Jan 20. doi:10.3390/pathogens11020121
2. R. Jayabalan, R.V. Malbaša, E.S. Lončar, J.S. Vitas, M. Sathishkumar
A review on kombucha tea-microbiology, composition, fermentation, beneficial effects, toxicity, and tea fungus
Compr Rev Food Sci Food Saf, 13 (4) (2014), pp. 538-550
3. C. Dufresne, E. Farnworth
Tea, Kombucha, and health: a review
Food Res Int, 33 (6) (2000), pp. 409-421
4. Antolak, Hubert et al. “Kombucha Tea-A Double Power of Bioactive Compounds from Tea and Symbiotic Culture of Bacteria and Yeasts (SCOBY).” Antioxidants (Basel, Switzerland) vol. 10,10 1541. 28 Sep. 2021,
5. Villarreal-Soto SA, Beaufort S, Bouajila J, Souchard JP, Taillandier P. Understanding Kombucha Tea Fermentation: A Review. J Food Sci. 2018;83(3):580-588.
6. Malbaˇsa, R. V., Loncar, E. S., Vitas, J. S., & ˇ Canadanovi ˇ c-Brunet, J. M. (2011). Influence of ´ starter cultures on the antioxidant activity of Kombucha beverage. Food Chemistry, 127(4), 1727–1731.
7. Chu, S. C. & Chen, C. Effects of origins and fermentation time on the antioxidant activities of kombucha. Food Chem. 98, 502–507 (2006).
8. Jayabalan, Rasu et al. “A Review on Kombucha Tea-Microbiology, Composition, Fermentation, Beneficial Effects, Toxicity, and Tea Fungus.” Comprehensive reviews in food science and food safety vol. 13,4 (2014): 538-550.
9. Ziemlewska, A., Nizioł-Łukaszewska, Z., Bujak, T. et al. Effect of fermentation time on the content of bioactive compounds with cosmetic and dermatological properties in Kombucha Yerba Mate extracts. Sci Rep 11, 18792 (2021
10. Zillich, O. V., Schweiggert-Weisz, U., Eisner, P. & Kerscher, M. Polyphenols as active ingredients for cosmetic products. Int. J. Cosmet. Sci. 37, 455–464 (2015).
11. Chen, Q. et al. Edible flowers as functional raw materials: A review on anti-aging properties. Trends Food Sci. Technol. 106, 30–47 (2020)
12. Lintner K. Cosmetic or dermopharmaceutical compositions containing kombucha. Google Patents; 2008.
13. Baumann LS. Less-known botanical cosmeceuticals. Dermatol Ther. 2007;20:330-342.
14. Pakravan N, Mahmoudi E, Hashemi SA, Kamali J, Hajiaghayi R, Rahimzadeh M, Mahmoodi V. Cosmeceutical effect of ethyl acetate fraction of Kombucha tea by intradermal administration in the skin of aged mice. J Cosmet Dermatol. 2018 Dec;17(6):1216-1224.