Bee pollen is flower pollen with nectar and salivary substances of bees and rich in essential components. Bee pollen showed antioxidant and tyrosinase inhibitory activity in our assay system. To maximize the antioxidant and tyrosinase inhibitory activity of bee pollen, extraction conditions, such as extraction solvent, extraction time, and extraction temperature, were optimized using response s...

Ii(loleacetic acid is inactivated by mushroom tyrosinase or a tyrosinase present in dialyzed extracts of Osmunda leaves, but only when catechol or pyrogallol are also added. Tyrosine and DOPA do not promote IAA inactivation, although these phenols are oxidized by the enzvme. It appears probable that a reaction occurs between IAA and one of the intermediate compounds formed during the oxidation ...

Tyrosinase is a key enzyme for melanin biosynthesis, catalyzing the oxidation of L-tyrosine to L-dopaquinone. The tyrosinase inhibition is an effective approach to control hyperpigmentation in human skin and enzymatic browning in fruits and vegetables. Kojic acid is a naturally-occurring tyrosinase inhibitor which has been clinically used to treat the hyperpigmentation of skin. However, kojic a...

We compared the ability of two enzymes to catalyze the formation of gels from solutions of gelatin and chitosan. A microbial transglutaminase, currently under investigation for food applications, was observed to catalyze the formation of strong and permanent gels from gelatin solutions. Chitosan was not required for transglutaminase-catalyzed gel formation, although gel formation was faster, an...

The development of antimelanogenic agents is important for the prevention of serious aesthetic problems such as melasmas, freckles, age spots, and chloasmas. In the course of screening for melanin synthesis inhibitors, we found that the culture broth from an insect morphopathogenic fungus, Beauveria bassiana CS1029, exhibits potent antimelanogenic activity. We isolated and purified an active me...

The morphological basis of glomerular filtration and protein reabsorption in mouse kidney was examined by using mushroom tyrosinase subunits (mol wt 34,500), as an ultrastructural tracer. Almost immediately after injection tyrosinase reaction product was visualized in the glomerulus, and within the capillary lumen extending into the endothelial fenestrae. The entire basement membrane showed acc...

A new bioactive compound, namely desmodianone H(1), and another known compound uncinanone B(2) were first isolated using bioactivity-guided isolation from the leaves of Lespedeza maximowiczii and structures were elucidated by comprehensive analysis of their nuclear magnetic resonance and mass spectrometry data. Compounds 1 and 2 exhibited strong inhibitory effects on mushroom tyrosinase activity.

Tyrosinase (o-diphenol: O2 oxidoreductase, EC 1.10.3.1) has been purified from a commercial lyophilized powder prepared from edible mushrooms. Specific activities toward DL-dihydroxyphenylalanine and catechol, homogeneity, molecular weight, absorption spectrum, amino acid composition, and copper content of the preparation are comparable to other purified samples of tyrosinase prepared from fres...

We simulated the docking of the tertiary structure of mushroom tyrosinase with our compounds. From the structure-tyrosinase inhibitory activity relationship, it is notable that compounds 4, 8 and 11 showed similar or better activity rates than kojic acid which was used as a positive control. Compounds 17, 21, and 23 among benzene analogs that possess the same substituent showed significantly lo...

ABSTRACT. Ti(III) and (IV) hydrazide complexes were synthesized, characterized, screened for their tyrosinase lipoxygenase inhibitory cytotoxic activities. The geometry of is tentatively assigned as octahedral. Magnetic moments found around 1.7 B.M. electronic spectral transition in the range 495-518 nm. Evaluation Ti(IV) activities revealed varying inhibition potential. Hydrazide ligands inact...