Whitening effects of exosomes derived from Bacillus sp. JSP-1 isolated from Lysimachia davurica flowers in B16F10 melanoma cells

Exosomes are a type of extracellular vesicle with a nanosized structure ranging from approximately 50-150 nm in diameter and play important roles in intercellular communication.Due to their high biocompatibility and stability, exosomes have recently attracted considerable attention as promising biomaterials in the fields of cosmetics and drug delivery systems.In this study, exosomes derived from Bacillus sp.JSP-1 isolated from the flowers of Lysimachia davurica were purified using tangential flow filtration.To evaluate the whitening activity of JSP-1-derived exosomes, melanin content and tyrosinase activity were analyzed in B16F10 melanoma cells.The results demonstrated that JSP-1 exosomes significantly reduced melanin production and tyrosinase activity in a concentration-dependent manner without inducing cytotoxicity.Furthermore, Western blot analysis revealed that JSP-1 exosomes concentration-dependently downregulated microphthalmiaassociated transcription factor and melanogenesis-related proteins, including tyrosinase, tyrosinase-related protein-1, and tyrosinaserelated protein-2.These findings suggest that JSP-1-derived exosomes possess anti-melanogenic activity and may have potential as functional cosmetic ingredients for skin-whitening applications.