HE question of the relation between melanin synthesis and morphogenesis Thas been raised previously. HIRSCH 1954 and WESTERGAARD and HIR~CH 1954 concluded from their experiments with a wild-type strain of Neurospora crassa that the melanin pigments or the enzyme tyrosinase, a phenol oxidase which is responsible for the first steps in melanin synthesis, play a role in the formation of the protop...

We assessed the effects of arbutin on the pigmentation of cultured normal human melanocytes. As indicated by a cell-blotting assay, arbutin at concentrations in the range of 0.5-8 mM increased the pigmentation of the cultured melanocytes, while kojic acid at concentrations in the range of 0.5-4 mM decreased the pigmentation. The pigmentation-augmenting effect of arbutin was further confirmed by...

OBJECTIVE To examine whether earthworms of Eisenia fetida, Lumbricus rubellus and Eudrilus eugeniae extracts have elastase, tyrosinase and matrix metalloproteinase-1 (MMP-1) inhibitory activity. METHODS The earthworms extract was screened for elastase, tyrosinase and MMP-1 inhibitory activity and compared with the positive controls. It was also evaluated for whitening and anti-wrinkle capacit...

Agaricus bisporous tyrosinase was immobilized on commercial available epoxy-resin Eupergit®C250L and then coated by the Layer-by-Layer method (LbL). The two novel heterogeneous biocatalysts were characterized for their morphology, pH and storage stability, kinetic properties (K(m), V(max), V(max)/K(m)) and reusability. These biocatalysts were used for the efficient and selective synthesis of bi...

Experimental autoimmune vitiligo was induced by the intradermal injection of the purified mushroom tyrosinase emulsified in Complete Freunds Adjuvant (CFA) in female C57BL/6 mice. The onset of vitiligo was characterized by hair hypopigmentation and total melanocyte depletion in the basal layer of the epidermis. Oral administration of semipurified mushroom tyrosinase prevented experimental autoi...

PURPOSE The aim of this study was to investigate acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and antityrosinase activities of extracts from ten Piper species namely; P. caninum, P. lanatum, P. abbreviatum, P. aborescens, P. porphyrophyllum, P. erecticaule, P. ribesioides, P. miniatum, P. stylosum, and P. majusculum. METHODS Anticholinesterase and antityrosinase activities were e...

The objective of this study was to assess the structure, anti-tyrosinase activity, and mechanism of proanthocyanidins extracted from Rhododendron pulchrum leaves. Results obtained from mass spectra of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and high performance liquid chromatography electrospray ionization mass spectrometry (HPLC-ESI-MS) revea...

Nepeta (Lamiaceae) is an important genus with beneficial medicinal properties. N. sintenisiiBornm. has been used in folk medicine of Iran to cure various diseases. We investigated theanti-melanogenesis effects of n-hexane, MeOH, CH2Cl2, n-BuOH, EtOAc, and H2O extractsisolated from the plant in B16 melanoma cells. Various assays including cytotoxicity, mushroomtyrosinase inhibition, inhibition o...