Preparation of Isoflavone glucosides from Soy germ and β-Glucosidase from Bacillus coagulans PR03 for Isoflavone aglycones Production

Abstract

This research optimized isoflavone aglycones production from soy germ. The processes included isoflavone glucosides extraction from soy germ to use as a precursor for isoflavone aglycones production. β-glucosidase was produced from B. coagulans PR03 and used to convert glucosides form to aglycones. For the β-glucosidase production using Plackett and Burman Design (n=8) and 22 factorial experiment with central composite design, the suitable medium containing peptone (2.00%), beef extract (14.84%), glucose (2.00%) and magnesium sulphate (0.10%) with pH 7.96 was used and incubated at 30 °C. The resulting β-glucosidase activity was 4.01 mU/ml. However, the isoflavone glucosides was extracted by use of soy germ in 80% ethanol at a ratio of 1:5 with high power ultrasonication technique at 80 oC for 160 min using a completely randomized design. The extracted isoflavone glucosides contained daidzin, genistin and glycitin of 307.47, 214.84 and 73.63 mg/100 g. (dry basis), respectively. Finally, isoflavone aglycones production was optimized using 22 factorial experiment with central composite design, the total isoflavone glucosides (595.95 mg/100 g. dry basis) was convert to isoflavone aglycones (112.90 μg/ml) by β-glucosidase at 37.5 °C for 120 hours.