Postbiotics are bacterial-derived products, meaning “a preparation of inanimate microorganisms, and/or their components, and the metabolites produced by them during the fermentation process (organic acids, peptides, enzymes, bacteriocins, etc.) that confer health benefits to the host.”
They are often also called “para-probiotics,” “ghost probiotics,” “tyndallized probiotics,” or, more simply, “inactivated probiotics” as they are derived from the more common probiotics. In most cases, they undergo mild heat treatments for the reduction of the total bacterial load, without altering their intrinsic functional characteristics.
Compared to probiotics, the main characteristics of postbiotics are:
- Greater stability: since there are no live microorganisms, they are more resistant to external insults. Their stability appears good even after years of storage at room temperature.
- Greater safety: inactivated bacteria lose their ability to replicate; it is therefore reasonable to assume a better safety profile compared to probiotics.
The use of postbiotics in cosmetics is now growing, both for their proven beneficial effect, which we will discuss later, but also and above all for their greater safety and stability. By not having to control bacterial growth, the postbiotic product is safer and more stable (longer shelf-life), bringing certain benefits to both consumers and companies that decide to invest in their development.
Beneficial effects of postbiotics on the skin
The skin is a complex ecosystem where millions of microorganisms reside, normally maintaining a balance between protective and pathogenic species. The alteration of this balance, known as dysbiosis, is associated with skin problems such as dry skin, sebum imbalance, psoriasis, etc.
We have observed, through in-vitro and in-vivo tests, the beneficial effects of postbiotics on the skin, in particular they are able to:
- promote the balance of the skin microbiota, inhibiting the proliferation of pathogenic species;
- increase the body’s antimicrobial defenses;
- improve skin hydration.
The metabolites present in postbiotics also inherently possess antioxidant and anti-inflammatory properties that could be exploited to confer anti-pollution and anti-aging properties to a cosmetic formulation. Finally, considering that the pH of the epidermis normally oscillates between 4.4 and 5.6, the lactic acid produced by lactic acid bacteria can play a role in controlling the skin’s acidity level. Alterations of the normal skin pH value, such as neutral or alkaline pH, can compromise the skin’s defensive capacity and its elasticity. Furthermore, for purely cosmetic purposes, lactic acid can also be used as a mild exfoliant.
Currently, there are still few postbiotic products on the market in the cosmetic sector, but in light of these properties, it is clear that the applications of postbiotics in this sector can be varied and numerous, also with a view to green and low environmental impact product lines.
Conclusion
I.T.P. SRL, thanks to its solid expertise in fermentation processes and functional foods, is able to support research and development projects for the identification and production of postbiotics usable in cosmetic formulations.
In particular, we guide:
- the selection of the bacterial strain and the substrate to be fermented. The use of natural matrices to be subjected to the fermentation process is strategic in order to exploit and enhance their intrinsic functional characteristics. This approach will also allow for the obtainment of naturally derived products that can be used as an ingredient for a formulation;
- the development of an optimized fermentation process;
- the identification and optimization of the treatment for the inactivation of the fermented product and the obtainment of the postbiotic;
- the characterization of the obtained product in order to identify its potential and the most suitable application within the Personal Care product category.
Bibliography
- The International Scientific Association of Probiotics and Prebiotics (ISAPP) consensus statement on the definition and scope of postbiotics. Salminen et al; Nature Review- Gastroenterology & Hepatology. Volume 18. September 2021
- The Skin Microbiome. Elizabeth A. Grice and Julia A. Segre. Nat Rev Microbiol. 2011 April; 9(4): 244–253. doi: 10.1038/nrmicro2537.
- Empowering the Micro-Word of the Skin Microbiota: approaches to maintain nature’s ideal homeostasis for betterment of cosmetic product. Federica Carlomagno and Stefania Zanzottera. 6-2019. Euro Cosmetics.
- A 28 Day Clinical Assessment of a Lactic Acid-containing Antimicrobial Intimate Gel Wash Formulation on Skin Tolerance and Impact on the Vulvar Microbiome. Bruning E. et al.; Antibiotics 2020, 9, 55; doi: 10.3390/antibiotics9020055
