Beneficial Bio-Extract of Camellia sinensis var. assamica Fermented with a Combination of Probiotics as a Potential Ingredient for Skin Care

Biotechnology, cosmetics, and aesthetic remedies are now inextricably intertwined due to the production of alternative, more effective, and safer active ingredients. Additionally, there has been an increase in demand for natural cosmetic ingredients across the globe. Camellia sinensis var. assamica (Miang tea) is a good alternative because of several biological activities, and is commercially cultivated as a resource in northern Thailand. The process of fermentation mediated by probiotics can enhance the bioavailability of compounds, transform bioactive compounds, and decrease chemical solvent use for sustainability. This study aims to apply the functional evaluation of Miang tea bio-extracts to promote skin health. On the basis of their bioactive enzymes, β-glucosidase, and antioxidant properties, the strains Lacticaseibacillus rhamnosus (previously Lactobacillus rhamnosus), Lactiplantibacillus plantarum (previously Lactobacillus plantarum), and Saccharomyces cerevisiae were used as mixed probiotic starter cultures. The activities of white, green, and black Miang tea bio-extracts, including ferric reducing antioxidant power, lipid peroxidation, nitric oxide inhibition, tyrosinase inhibition, collagenase inhibition (MMP-1 and MMP-2), and antimicrobial activity, were all considerable after 7 days of fermentation time. Additionally, phenolic antioxidant compounds (gallic acid, epigallocatechin gallate, caffeic acid, caffeine, and p-coumaric acid) were identified. The current study’s findings can determine the most effective fermentation time and dose of bio-extract, as well as suggest improvements in bioactive compounds for use in skin care formulations. These results will be used for testing on human participants in further work.