Bioactive constituents of Spatholobus suberectus in regulating tyrosinase-related proteins and mRNA in HEMn cells

Twelve components were isolated from Spatholobus suberectus by using bio-guided assay. Among them, butin (7) is the most active component in reducing expression of cellular tyrosinase and in lowering melanin content in human epidermal melanocytes (HEMn). This inhibition is exerted through inhibition of transcription of the genes encoding tyrosinase, tyrosinase-related proteins 1 and 2.