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Bark of Quercus coccifera is widely used in folk medicine. We tested tyrosinase and α-glucosidase inhibitory effects of Q. coccifera bark extract and isolated compounds from it. The extract inhibited tyrosinase with an IC₅₀ value of 75.13 ± 0.44 µg/mL. Among the isolated compounds, polydatin (6) showed potent tyrosinase inhibition compared to the positive control, kojic acid, with an IC₅₀ value of 4.05 ± 0.30 µg/mL. The Q. coccifera extract also inhibited α-glucosidase significantly with an IC₅₀ value of 3.26 ± 0.08 µg/mL. (-)-8-Chlorocatechin (5) was the most potent isolate, also more potent than the positive control, acarbose, with an IC₅₀ value of 43.60 ± 0.67 µg/mL. According to the kinetic analysis, 6 was a noncompetitive and 5 was a competitive inhibitor of tyrosinase, and 5 was a noncompetitive α-glucosidase inhibitor. In the light of these findings, we performed in silico molecular docking studies for …