College of Biological Science and Engineering, Fuzhou University, Fuzhou, Fujian 350116, China.
College of Biological Science and Engineering, Fuzhou University, Fuzhou, Fujian 350116, China.
Food Chem. 2018 Jul 15;254:122-128. doi: 10.1016/j.foodchem.2018.01.158. Epub 2018 Jan 31.
Oat bran was fermented by filamentous fungi to improve the extractability of β-glucan. Box-Behnken experimental design and response surface methodology were used to obtain the maximum extractability of β-glucan. Inoculum volume, fermentation temperature, and time were evaluated as three variables. Under optimal fermentation conditions, the extractability of β-glucan in oat bran increased to 45.57 ± 1.82% and 51.10 ± 2.32% by Aspergillus niger and Rhizopus oryzae, respectively. The extractability was about 3-fold of that before fermentation (16.86 ± 0.76%). Fermentation of oat bran by Aspergillus niger and Rhizopus oryzae reduced the molecular weight of the extracted β-glucan from 6.74 × 10 to 2.84 × 10 and 2.20 × 10 Da, respectively. Correspondingly, the apparent viscosity of the extracted β-glucan decreased after fermentation. But the increased extractability compensated for the reduced molecular weight in the formation of viscous solution. The molecular structure and cellotriosyl/cellotetraosyl ratio were not affected by filamentous fungi fermentation.
米糠经丝状真菌发酵以提高β-葡聚糖的提取率。采用 Box-Behnken 实验设计和响应面法，以获得β-葡聚糖的最大提取率。接种量、发酵温度和时间被评估为三个变量。在最佳发酵条件下，黑曲霉和米根霉分别使米糠中β-葡聚糖的提取率提高到 45.57±1.82%和 51.10±2.32%。提取率约为发酵前的 3 倍（16.86±0.76%）。黑曲霉和米根霉发酵米糠降低了提取β-葡聚糖的分子量，分别从 6.74×10 降至 2.84×10 和 2.20×10 Da。相应地，发酵后提取的β-葡聚糖的表观粘度降低。但是，增加的提取率弥补了粘性溶液形成过程中分子量的降低。丝状真菌发酵不影响β-葡聚糖的分子结构和纤维三糖/纤维四糖比。
