Investigation of tyrosinase inhibitory activity of thymol and quinones of Nigella sativa using molecular docking

Hyperpigmentation is a skin-related problem caused by overproduction of melanin due to tyrosinase overexpression. Several compounds from Nigella sativa (N. sativa) have showed a potential to treat hyperpigmentation by regulating melanogenesis via tyrosinase inhibitory mechanism. In this study, a molecular docking approach was selected to investigate the tyrosinase inhibitory activity of thymol and three quinone derivatives found in N. sativa. Results indicated that thymol and quinones of N. sativa showed affinity toward tyrosinase. However, only thymoquinone and dithymoquinone showed better affinity compared to its natural ligand, with binding free energy values of −25.98 and −28.70kJ/mol, respectively. It is also revealed from the result that the strong affinity and better binding stability of thymol and quinone derivatives toward tyrosinase were contributed from hydrogen bonding and hydrophobic interaction.