Penentuan Kadar Genistein dan Aktivitas Hambatan Tirosinase Kedelai (Glycine max) Terfermentasi Aspergillus oryzae

Abstrak

The purpose of this study was to determine the genistein content and tyrosinase inhibition activity of fermented and unfermented soybean extracts. Soybean was fermented by Aspergillus oryzae for 4 days, with genistein content and tyrosinase inhibition activity were monitored each day. Genistein content was determined using TLC-densitometer, while the tyrosinase inhibition activity was evaluated using spectrophotometric assay. The result showed that the genistein content was increased during 1-3 days of fermentation (45.645-1256.042 μg/g extract), but it decreased at the 4th day of fermentation (54.373 μg/g extract). Similarly, inhibitor tyrosinase activity (expressed by IC50 value) was also increased for 1-3 days of fermentation, but it decreased at the 4th day of fermentation. It was known that genistein content was correlated with tyrosinase inhibition activity (R2 = 0.949).