Licochalcone A (LCA), a flavonoid isolated, presents obvious anti-cancer effects, displays broad-spectrum inhibition against UDP-glucuronosyltransferases (UGTs) [1]. Licochalcone A (LCA) exhibits strong inhibitory effects against UGT1A1, 1A3, 1A4, 1A6, 1A7, 1A9, and 2B7 (both IC50 and Ki values lower than 5 μM) [2].