Microbial pigments as multi-functional cosmeceuticals: mechanism of action and sustainable production.

Microbial pigments have emerged as promising multifunctional agents for cosmeceutical applications owing to their sustainable production and diverse mechanisms of action. Bacteria, fungi, yeasts, and microalgae produce carotenoids, melanin, violacein, prodigiosin, and phycobiliproteins which interact with keratinocytes, melanocytes, fibroblasts and sebocytes in the skin to produce antioxidant, anti-inflammatory, anti-melanogenic, antimicrobial, and photoprotective effects. These bioactive pigments provide skin protection, anti-aging benefits, skin brightening, and anti-acne properties by modifying key signalling pathways like Nrf2 NF-κB and those involved in melanogenesis. Compared with plant-derived pigments, microbial pigments offer advantages such as controlled production, batch-to-batch consistency, scalability, and year-round availability. Additionally, this review highlights environmentally friendly extraction techniques such as metabolic engineering, agro-waste repurposing, and fermentation-based production. Because of all these properties, microbial pigments are being considered as eco-friendly, bioactive, and sustainable alternatives that can replace synthetic compounds. Overall, this review positions microbial pigments as future next-generation cosmeceutical ingredients, for which further research and optimization are needed for commercial application.