文摘
A novel 尾-glucosidase named BglW5 from Gongronella sp. was isolated, purified, and characterized for the first time. Under solid state fermentation, the yield of BglW5 was 49.9 U/g fermented medium. BglW5 was stable over a wide pH range of 3.0鈥?.5 and retained more than 50% of its maximal activity after incubation at 25 掳C for 96 h. The half-lives of BglW5 were 20 h at 60 掳C, and 1 h at 70 掳C. The activity of BglW5 was stimulated by xylose and fructose at concentrations up to 500 mM, with maximal stimulatory effect of 1.6-fold and 2.2-fold, respectively. BglW5 converted isoflavone glycosides to aglycones, with a hydrolysis rate of 96.2% for daidzin and 96.7% for genistin. The productivities were 1.5 mmol L鈥? h鈥? for daidzein and 1.23 mmol L鈥? h鈥? for genistein, respectively. These features suggest that BglW5 has great application potential in the hydrolysis of soybean isoflavone glycosides.
Keywords:
zygomyzetes; solid-state fermentation; daidzin; genistin