Departamento de Ciência e Tecnologia de Alimentos, Universidade Estadual de Londrina, 86057-970 Londrina, Paraná, Brazil.
Departamento de Ciências Farmacêuticas, Universidade Estadual de Londrina, 86057-970 Londrina, Paraná, Brazil.
Food Chem. 2014;152:56-65. doi: 10.1016/j.foodchem.2013.11.101. Epub 2013 Nov 27.
The solid state fermentation (SSF) parameters of defatted soybean flour (DSF) with Aspergillus oryzae IOC 3999/1998 or Monascus purpureus NRRL 1992 was evaluated using a rotational central composite experimental design to optimise the production of β-glucosidase and convert glycosidic isoflavones in aglycones. Variables investigated were initial pH of DSF, volume of water added to 10 g of DSF and incubation temperature. β-Glucosidase activity was measured using the synthetic substrate, p-nitrophenyl-β-D-glucoside. The content of isoflavones was determinate by ultra performance liquid chromatography. The highest production of β-glucosidase for both strains occurred when adding 10 mL of water to the DSF, incubating at 30 °C and using 6.0 as the initial DSF pH. A. oryzae IOC 3999/1998 expressed β-glucosidase activity at 10.7 times higher than M. purpureus NRRL 1992. The DSF fermentation was more efficient in converting isoflavones with M. purpureus NRRL 1992.
采用旋转中心复合实验设计，评估米曲霉 IOC 3999/1998 或红曲霉 NRRL 1992 对脱脂豆粉（DSF）固态发酵（SSF）参数，以优化β-葡萄糖苷酶的生产，并将糖苷异黄酮转化为苷元。考察的变量为 DSF 的初始 pH、加到 10 g DSF 中的加水量和培养温度。使用合成底物对硝基苯-β-D-葡萄糖苷测定β-葡萄糖苷酶活性。采用超高效液相色谱法测定异黄酮含量。两种菌株的β-葡萄糖苷酶产量最高时，向 DSF 中加入 10 mL 水，在 30°C 下培养，初始 DSF pH 值为 6.0。A. oryzae IOC 3999/1998 的β-葡萄糖苷酶活性比 M. purpureus NRRL 1992 高 10.7 倍。红曲霉 NRRL 1992 发酵 DSF 更有效地将异黄酮转化。
