Potency of Indonesian Medicinal Plants as Tyrosinase Inhibitor and Antioxidant Agent

Abstract

The aim of this study is to screen whitening agent potency of 45 Indonesian plant materials from 35 species. All plant materials were extracted with methanol and 50% ethanol which resulted to 90 extracts. The methods for screening is based on tyrosinase inhibitor potency using mushroom tyrosinase and antioxidant activity using 1,1-diphenyl-2-picrylhydrazyl (DPPH). Scoring method was used to identify the best extract as whitening agent. Out of 90 extracts, merbau (Intsia palembanica) methanol and 50% ethanol extracts are the most potent extracts as tyrosinase inhibitor (for monophenolase and diphenolase). Their IC50 values are not significantly different with kojic acid as positive control. Based on antioxidant activity, merbau methanol extract (!Coe: 3.87 μg mL _,)is the best antioxidant together with kayu putih (Melaleuca cajuputi) ethanol 50% extract (!Coe: 5.76 μg mL _,) and Rhizapara sp. methanol extract (!Coe: 5.90 μg mL -'). Their !Coe values are not significantly different with (+)-catechin (IC50 : 2.94 μg mL - 1 ) as positive control. In conclusion, merbau methanol extract is the most potent extract as whitening agent based on scoring data from its tyrosinase inhibitory and antioxidant activities.