Plant-based prebiotics to modulate skin microbiota: a novel approach for next-generation cosmeceuticals

The skin microbiome maintains cutaneous homeostasis through colonization resistance and immune modulation, targeted prebiotic interventions however remain largely unexplored. The present study addresses this lacuna effectively demonstrating the ability of plant-derived prebiotics to selectively modulate key skin commensals and pathogenic bacteria thereby unraveling a new dimension to use of prebiotics in skin care. Linum usitatissimum (flaxseed) and Allium sativum (garlic) extracts used herein exhibited complete growth inhibition of Staphylococcus aureus within 6 h, while Curcuma amada (mango ginger) rapidly halted the growth of Cutibacterium acnes within 15 min. Gas chromatography-mass spectrometry was carried out to unveil the bioactive constituents in plant-prebiotics as well as the exposed organisms. Field emission gun-scanning electron microscopy validated bacterial cell membrane disruption correlating with antimicrobial efficacy. Remarkably, Allium cepa (onion) and Tinospora cordifolia (guduchi) selectively enhanced the proliferation of Staphylococcus epidermidis while simultaneously inhibiting pathogenic species. Metabolomic profiling revealed that prebiotic-stimulated S.epidermidis produced elevated levels of butyric and succinic acids that are documented to have anti-bacterial activity. Plant-based prebiotics can thus be strategically reinforced to benefit skin microbiota with simultaneous inhibition of skin pathogens, providing a scientific foundation for microbiome-targeted cosmeceuticals.