Antioxidant Activity and Whitening Efficacy of Ethanolic Extract of Herb Complex (Oenothera laciniata, Phellinus linteus and Glycyrrhiza uralensis Fischer)

Abstract

The aim of this study was to assess the antioxidant activity and whitening efficacy of ethanolic extract of herb complex (Oenothera laciniata, Phellinus linteus and Glycyrrhiza uralensis Fischer). The antioxidant activity was evaluated by DPPH-radical inhibition activity, xanthine oxidase (XO) inhibition activity, superoxide dismutase (SOD)like activity, and ABTS radical inhibition activity. Whitening efficacy was evaluated by mushroom tyrosinase inhibition activity. In the antioxidant activities of ethanolic extract of herb complex at 1,000 μg/mL concentration, DPPH radical inhibition activity was over 80% and similar to that of BHA, positive control. XO inhibition activity was over 90%. The SOD-like activity was over 30%. ABTS radical inhibition activity was over 95%. The ethanolic extract of herb complex reduced the mushroom tyrosinase activity in a dose-dependant manner, showing a inhibitory rate over 60% at 1,000 μg/mL concentration compared to the untreated control. The ethanolic extract of herb complex did not affect on cell growth at test concentrations (0~1,000 μg/mL). From these results, it was found that the ethanolic extract of herb complex had a good antioxidant activity and whitening efficacy. Hence, it could be used as cosmetic ingredients for skin whitening and/or skin anti-ageing.