Abstract:
This study aimed to compare the antioxidant and tyrosinase inhibitory activities of green tea extract (GTE) and black tea extract (BTE). The DPPH radical scavenging assay and the tyrosinase inhibition assay were employed to evaluate antioxidant capacity and melanogenesis inhibition, respectively. The tea extracts were standardized to contain not less than 25% EGCG for GTE and theaflavin for BTE. Each extract was tested at elevent different concentrations (1.0000.001 mg/mL), and the percentage of inhibition was calculated based on triplicate measurements. Statistical analyses were conducted using Two-way ANOVA and One-way ANOVA followed by multiple comparisons. The results indicated that BTE exhibited slightly higher average antioxidant activity than GTE (74.47% vs. 71.97%). However, GTE demonstrated stronger antioxidant effects at higher concentrations, while BTE was more effective at lower concentrations. Regarding tyrosinase inhibition, BTE showed significantly higher inhibitory activity than GTE across all concentrations (65.74% vs. 38.29%). These findings are consistent with previous studies and support the potential use of tea extracts as natural ingredients in whitening and anti-aging cosmetic formulations.