Abstract ▼ AI-Helper

Tyrosinase, an enzyme catalyzing biosynthsis of melanin pigments participating in coloring of skin, hair and eyes, is widely distributed in nature. The inhibitory compounds of tyrosinase have been extensively used as a cosmetic agent with skin-whitening effect. The extract of Lespedeza cyrtobotrya s...

Tyrosinase, an enzyme catalyzing biosynthsis of melanin pigments participating in coloring of skin, hair and eyes, is widely distributed in nature. The inhibitory compounds of tyrosinase have been extensively used as a cosmetic agent with skin-whitening effect. The extract of Lespedeza cyrtobotrya showed inhibitory activity against mushroom tyrosinase. The compounds were purified from methanol extract of L. cyrtotrya followed by several chromatographic methods. Four active compounds against pigmentation were identified as haginin A, dalbergioidin, genistein and isopterofuran by spectroscopic methods. Among them, haginin A and dalbergioidin inhibted a melanin biosynthesis inhibition of Streptomyces bikiniensis. All compounds were assayed pigmentation test using immortalized mouse melanocyte, Melan-A cell. More than fifty percents of melanin contents were decreased by haginin A and dalbergioidin at 1 ㎍/㎖ and 10 ㎍/㎖, respectively. Haginin A also decreased level of tyrosinase and TRP1. The kinetic study of L-tyrosine oxidation catalyzed by mushroom tyrosinase was accomplished in the presence of haginin A, dalbergioidin and isopterofuran. All three compounds were noncompetitive inhibitors of mushroom tyrosinase.

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