Multifunctional Cosmetic Potential of Acer tegmentosum Extracts

This study investigated the antioxidant, anti-inflammatory, and anti-melanogenic activities of Acer tegmentosum bark and leaf extracts prepared with ethanol and distilled water. The extraction yields of leaf extracts were approximately two-fold higher than those of the bark, regardless of the solvent used. In antioxidant assays, all extracts exhibited dose-dependent radical scavenging activities; notably, the ethanol bark extract (ATBE) showed the strongest DPPH and ABTS scavenging effects with IC₅₀ values of 15.8 μg/mL and 85.6 μg/mL, respectively. Total polyphenol content was highest in the ethanol bark extract (ATBE), suggesting efficient recovery of phenolic antioxidants by ethanol extraction. In anti-melanogenic assays, both ATBE and ATLE inhibited tyrosinase activity and DOPA autooxidation in a concentration-dependent manner, demonstrating dual whitening mechanisms involving enzyme inhibition and antioxidative protection. Moreover, ATLE significantly suppressed nitric oxide production and downregulated inflammatory cytokines (TNF-α, IL-6, and PGE₂) and proteins (iNOS, COX-2) in LPS-stimulated RAW 264.7 cells, confirming potent anti-inflammatory activity. Collectively, these findings suggest that A. tegmentosum extracts, particularly ATLE, possess strong antioxidant and anti-inflammatory properties with skin-whitening potential, supporting their application as multifunctional cosmetic ingredients.