Tyrosinase inhibitors as potential antibacterial agents

Tyrosinase is a copper-containing enzyme that catalyzes the biosynthesis of melanin. This enzyme is present in bacteria, fungi, plants and animals, and plays multiple roles in pigmentation, wound healing, radiation protection, primary immune responses and the undesirable browning of fruits and vegetables. Selective tyrosinase inhibitors hence have potential application in diverse areas of agriculture, cosmetics and pharmaceuticals. In the past decade many natural and synthetic tyrosinase inhibitors have been evaluated, with many reported to also possess intrinsic antibacterial activity. Further, the enzyme product melanin has been shown to compromise the activity of traditional antibiotics. Due to the antibiotic resistance crisis and the slow development of new antibiotics, tyrosinase inhibitors may have potential for development of novel antimicrobials or antibiotic adjuvants that enhance activity of incumbent drugs. This review focuses on the antibacterial activity of natural and synthetic tyrosinase inhibitors reported in the past ten years and explores the possibilities for synergism of anti-tyrosinase with anti-bacterials.