The goal of this study was to identify phytochemicals with inhibitory activity against tyrosinase. Nine compounds 1-9 were isolated from the tubers of Apios americana. This is the first report of aromadendrin 5-methyl ether (1) being isolated from the Apios species. Among them, compounds 2 and 8 showed inhibitory activity toward tyrosinase. Based on a Dixon plot, the potential Ki values of comp...

Skin pigmentation disorders typically involve an overproduction or uneven distribution of melanin, which results in skin spots. Resveratrol can inhibit tyrosinase, the active enzyme in the synthesis of melanin, but it does not inhibit the synthesis of melanin to an extent that enables its use alone as a skin whitening agent in pharmaceutical formulations, so its use as a coadjuvant in treatment...

BACKGROUND Hyperpigmentary disorders like melasma, actinic and senile lentigines are a major cosmetic concern. Therefore, many topical products are available, containing various active ingredients aiming to reduce melanin production and distribution. The most prominent target for inhibitors of hyperpigmentation is tyrosinase, the key regulator of melanin production. Many inhibitors of tyrosinas...

Reduced or defective melanin skin pigmentation may cause many hypopigmentation disorders and increase the risk of damage to the skin triggered by UV irradiation. Ginsenosides Rb1 and Rg1 have many molecular targets including the cAMP-response element-binding protein (CREB), which is involved in melanogenesis. This study aimed to investigate the effects of ginsenosides Rb1 and Rg1 on melanogenes...

In this study, we screened compounds with skin whitening properties and favorable safety profiles from a series of marine related natural products, which were isolated from Formosan soft coral Cladiella australis. Our results indicated that 4-(phenylsulfanyl)butan-2-one could successfully inhibit pigment generation processes in mushroom tyrosinase platform assay, probably through the suppressio...

Okadaic acid is a C38 fatty acid derivative that is known to specifically inhibit the activity of protein phosphatase 2A (PP2A). Previously, we reported that inhibition of PP2A by okadaic acid elicited extracellular signal-regulated kinase (ERK) activation, and that PP2A may be involved in melanogenesis. However, the effects of okadaic acid on melanogenesis have not been completely evaluated. I...

Melanin biosynthesis in insects involves the following three key steps: oxidation of tyrosine to dopa by monophenoloxidase (tyrosinase), conversion of dopa to dopachrome by diphenoloxidase and formation of melanin by polymerization of dopachrome.1] Whenthe larval haemolymphof Bombyxmori is exposed to air, it changes from pale yellow to black. This color change is based on melanin formation, by ...

Baicalein (1), 6-hydroxyapigenin (6), 6-hydroxygalangin (13) and 6-hydroxy-kaempferol (14), which are naturally occurring flavonoids from a set of 14 hydroxy-flavones tested, exhibited high inhibitory effects on tyrosinase with respect to L-DOPA, while each of the 5,6,7-trihydroxyflavones 1, 6, 13 or 14 acted as a cofactor to monophenolase. Moreover, 6-hydroxykaempferol (14) showed the highest ...