Abdella Asmaa, El-Baz Ashraf F, Ibrahim Ibrahim A, Mahrous Emad Eldin, Yang Shang-Tian
a Department of Industrial Biotechnology , Genetic Engineering and Biotechnology Research Institute, University of Sadat City , Sadat City , Egypt.
c William G. Lowrie Department of Chemical & Biomolecular Engineering , The Ohio State University , Columbus , OH , USA.
Nat Prod Res. 2018 Oct;32(20):2382-2391. doi: 10.1080/14786419.2017.1413569. Epub 2017 Dec 11.
β-glucosidase enzyme produced from Aspergillus niger NRRL 3122 has been partially purified and characterised. Its molecular weight was 180 KDa. The optimal pH and temperature were 3.98 and 55 °C, respectively. It promoted the hydrolysis of soy flour isoflavone glycosides to their aglycone. Two-level Plackett-Burman design was applied and effective variables for genistein production were determined. Reaction time had a significant positive effect, and pH had a significant negative effect. They were further evaluated using Box-Behnken model. Accordingly, the optimal combination of the major reaction affecting factors was reaction time, 5 h and pH, 4. The concentration of genistein increased by 11.73 folds using this optimal combination. The antioxidant activity of the non-biotransformed and biotransformed soy flour extracts was determined by DPPH method. It was found that biotransformation increased the antioxidant activity by four folds.
由黑曲霉NRRL 3122产生的β-葡萄糖苷酶已被部分纯化并进行了表征。其分子量为180 kDa。最佳pH值和温度分别为3.98和55℃。它促进了大豆粉异黄酮糖苷水解为其苷元。应用了二级Plackett-Burman设计并确定了染料木素生产的有效变量。反应时间有显著的正效应，pH值有显著的负效应。使用Box-Behnken模型对它们进行了进一步评估。因此，影响主要反应的因素的最佳组合是反应时间5小时和pH值4。使用该最佳组合，染料木素的浓度增加了11.73倍。通过DPPH法测定了未生物转化和生物转化的大豆粉提取物的抗氧化活性。发现生物转化使抗氧化活性提高了四倍。
