Formation Mechanism for Potent Antioxidative o-Dihydroxyisoflavones in Soybeans Fermented with Aspergillus saitoi.
نویسندگان
چکیده
The formation mechanism for the potent antioxidative o-dihydroxyisoflavones, 8-hydroxydaidzein (8-OHD) and 8-hydroxygenistein (8-OHG), was studied by incubating whole soybeans in a solid culture and a soybean extract in a liquid culture with Aspergillus saitoi. Analyses of changes in the isoflavone analogue content, β-glucosidase activity, and isoflavone hydroxylation ability indicated that 8-OHD and 8-OHG were formed from daidzein and genistein, respectively, by microbial hydroxylation, being respectively liberated from daidzin and genistin by β-glucosidase from A. saitoi during incubation. No selective hydroxylation reaction at the 8-position of daidzein and genistein were apparent during the vegetative stage, but were induced at the stage of sporulation.
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ورودعنوان ژورنال:
- Bioscience, biotechnology, and biochemistry
دوره 63 5 شماره
صفحات -
تاریخ انتشار 1999