N-Nicotinoyl dopamine, a novel niacinamide derivative, retains high antioxidant activity and inhibits skin pigmentation.

We synthesized a novel derivative of a well-known skin-lightening compound niacinamide, N-nicotinoyl dopamine (NND). NND did not show inhibitory effects of tyrosinase and melanin synthesis in B16F10 mouse melanoma cells. However, NND retains high antioxidant activity without affecting viability of cells.

Changes in flavonoid content and tyrosinase inhibitory activity in kenaf leaf extract after far-infrared treatment.

The tyrosinase inhibitory activity of ethanolic extract of kenaf (Hibiscus cannabinus L.) leaf was evaluated before and after subjecting it to far-infrared (FIR) irradiation. The main component of the extract was analyzed as kaempferitrin (kaempferol-3,7-O-α-dirhamnoside).

Kojyl thioether derivatives having both tyrosinase inhibitory and anti-inflammatory properties.

This study was conducted to examine the tyrosinase inhibitory and anti-inflammatory activities of kojic acid derivatives. A series of kojic acid derivatives containing thioether, sulfoxide, and sulfone linkages were synthesized. In the tyrosinase assay, kojyl thioether derivatives containing appropriate lipophilic alkyl chains (pentane, hexane, and cyclohexane) showed potent inhibitory activity.

Biotransformation of mulberroside A from Morus alba results in enhancement of tyrosinase inhibition.

Mulberroside A, a glycosylated stilbene, was isolated and identified from the ethanol extract of the roots of Morus alba. Oxyresveratrol, the aglycone of mulberroside A, was produced by enzymatic hydrolysis of mulberroside A using the commercial enzyme Pectinex. Mulberroside A and oxyresveratrol showed inhibitory activity against mushroom tyrosinase with an IC(50) of 53.