Cosmetic Efficacy of the Topical Probiotic Micrococcus luteus Q24 in Healthy Human Adults

Probiotics in cosmetics represent a new and burgeoning area of research, attracting attention from cosmetic manufacturers and customers looking for natural or additional alternatives in their skincare regimens. Probiotics not only promote beneficial microbiomes to improve skin health but can also modulate the visual, topographical, and mechanical attributes to improve skin quality. This study was conducted in healthy adults to determine the effect of direct skin application of a topical serum formulation containing the live probiotic Micrococcus luteus Q24 on several key cosmetic skin quality parameters and its beneficial impact on the modulation of the skin microbiome. Quantitative changes in various skin parameters were measured using a skin analyser device and skin swabs were analysed using whole-genome sequencing to monitor microbial diversity and levels of probiotic colonization. Compared to the baseline, significant reductions in the pores, spots, wrinkles, and impurities scores, and an increase of 101% in the hydration score were observed. Additionally, 45–80% of participants showed a decrease in pores, spots, wrinkles, and impurities and 90% of participants showed an increase in hydration after 25 days of probiotic serum application. The WGS analysis of the skin swab samples showed a significant increase in the relative abundance of M. luteus Q24. The results from this study indicate that topical application of a serum containing the probiotic M. luteus Q24 offers the benefit of improving skin health quality.