Kim et al.: Tyrosinase Inhibitory Effects of Chromenes from Myagropsis myagroidesThe aim of this study was to elucidate the effect of Myagropsis myagroides extract on tyrosinase activity. Inhibition of tyrosinase was observed in the presence of an n-hexane fraction of Myagropsis myagroides. Separation of the n-hexane fraction using silica gel column chromatography yielded the chloroform:methanol (50:1) fraction, which showed the highest tyrosinase inhibitory activity. After several separation and purification steps, sargachromanol G, sargachromanol I, and mojabanchromanol b were obtained. These 3 chromene compounds displayed strong tyrosinase inhibitory activity. It could be concluded that Myagropsis myagroides is a potential source of natural antimelagenic compounds.

Kim et al.: Anticollagenase and Free Radical Scavenging Properties of Sargachromanol I The present study investigated the free radical scavenging activity and antiwrinkle properties of methanol extract, hexane, chloroform, ethyl acetate, and butanol partition fractions of Myagropsis myagroides. The methanol extract showed higher free radical scavenging (65.46 % at 0.5 mg/ml) and collagenase inhibitory activity (29.64 % at 1000 μg/ml) than the water extract (16.68 % at 0.5 mg/ml and <5 % at 1000 μg/ml). The hexane fraction exhibited strong free radical scavenging activity (96.36 % at 0.5 mg/ml) and collagenase inhibitory activity (IC 50 of 712.21 μg/ml). The hexane fraction was subjected to silica gel column chromatography, Sephadex LH-20 column chromatography, octadecyl silica Sepak cartridge, and preparative high performance liquid chromatography. Sargachromaol I was isolated, which showed strong free radical scavenging activity (95.82 % at 0.1 mg/ml) and collagenase inhibitory activity (IC 50 value of 54.01 μg/ml). The potential value in preventing skin aging could be confirmed through effects of extract from Myagropsis myagroides on free radical scavenging activity and collagenase inhibitory properties.