Figure 4
Inhibition of UVA-induced tyrosinase activity (A and B) and melanin synthesis (C and D) by AVS073 and GA. The tyrosinase activity and melanin production induced by a single UVA dose of 8 or 16 J/cm2, respectively, related to the protein concentration were expressed as a percentage of control (100%, the untreated control cells without UV irradiation). Values are expressed as mean±SEM. The statistical significance of differences between the control and UVA-irradiated cells was determined by Student’s t test and between UVA-irradiated and AVS073 extracts- or GA-treated cells by one-way ANOVA followed by Tukey’s post hoc test. *p < 0.05; **p < 0.01; ***p < 0.001 compared with AVS073- or GA-treated cells without UV irradiation.