Page 339 - Demo

SECTION II. APPLIED BIOTECHNOLOGY IN THE PHARMACEUTICAL INDUSTRY... 343 All 30 LAB strains used in the study were isolated from traditional fermented foods (including pickled radish, pickled eggplant, pickled mustard greens, pickled shrimps, and kimchi) and were obtained from the culture collection of the Institute of Biological and Food Technology, Hanoi Open University. There were 6 strains safe for human consumption and their glycosidase activity.This study determined the bacterial glycosidase activities as %u03b2-glucosidase and %u03b2-galactosidase. After inoculation for 24h in MRS broth medium, LAB cells were washed and adjusted to get 0D of 1 at wavelength 600nm. Then LAB was injected into the substrate solution of p-nitrophenyl-%u03b2-D-glucopyranoside or p-nitrophenyl-%u03b2-D-glucopyranoside for 1 h at 37%u00b0. Finally, absorbance at 400nm was measured, and glycolysis activities for %u03b2-glucosidase and %u03b2-galactosidase were analyzed via the release rate of para-nitrophenol (pNP) and ortho-nitrophenol (ONP). The glycolysis unit was %u00b5mol/min and calculated for 1 mg protein. 2.2. Preparation of rice bran extract LAB strains were activated in MRS agar media and cultured in 50mL MRS broth for 18h at 37%u00b0C. For fermentation medium, 100 g adlay bran powder and 500 g water were autoclaved and inoculated with 1% of the seed culture of each LAB strain and then incubated at 37%u00b0C for 48 h. The 20% adlay bran medium without LAB inoculation was used as a control (NF). Finally, fermented rice bran was extracted with ethanol 70%, concentrated, and stored at %u221220%u00b0C for further study.2.3. Total phenolics contentThe total phenolic content of each extract was determined using the Folin%u2013Ciocalteu method [6]. Briefly, 1 mL of extract solution was mixed with 1,000 %u00b5L of 20% (w/v) Folin%u2013Ciocalteu