원문정보
초록
영어
Phytochemical researches on Gastrodia elata Blume have revealed the existence of abundant
polyphenol glycosides such as gastrodin and parishins. On the basis of earlier reported
researches, we could expect that Gastrodia elata Blume is a medicinal herb useful for
polyphenol extraction as well as its polyphenol glycosides will be converted to the corresponding aglycones, which are further active skin whitening agents, by employing rice-koji
fermentation. HPLC results revealed that the polyphenol glycosides obviously underwent
deglycosidation reaction during rice-koji fermentation, thereby indicating that rice-koji is very
effective fungi in bioconverting vegetable polyphenol glycosides to alycones. Koji acid, a
typical Rice-koji metabolite, was identified by HPLC analysis as expected. Besides, increase of
p-hydroxybenzyl alcohol peak was very clear and other polyphenol aglycones were also
observed. These results indicated that koji fermentation is a good method to prepare skin
whitening products. In fact, differently from kojic acid, an excellent copper ion chelating agent
(direct tyrosinase deactivator), the polyphenol aglycones generated during koji fermentation
were expected to act as competitive substrates of tyrosinase, that is, they will retard or hinder
melanin synthesis by tyrosinase in human melanoma cells. Like this, combining two or more
whitening agents via different active mechanisms will contribute to further improvement of skin
pigmentation.