Stilbenes with tyrosinase inhibitory activity

Abstract

Tyrosinase (EC 1.14.18.1) is a multicopper monooxygenase enzyme with wide distribution. In mammals, it is responsible for pigmentation of skin, eyes and hair. The enzyme is involved in the undesired browning of bruised or cut fruits and vegetables. In insects, tyrosinase is one of the key enzymes in the molting process. Investigation of inhibitors of this enzyme may lead to development of novel skin whitening agents, anti-browning substances or insect control compounds. A number of naturally occurring stilbenes have been shown to possess strong tyrosinase inhibitory potential. Results from the studies on several natural and synthetic analogues have indicated that the number of free OH groups and their positions on the aromatic rings are important for the activity. This review gives a brief overview of the enzyme and describes tyrosinase-inhibiting stilbenoids regarding their botanical origin, structure-activity relationships, mechanisms of action and practical applications.