College of Food Science and Engineering, Hainan University, Haikou, 570228, China; College of Food and Bioengineering, Hezhou University, Hezhou, 542899, China.
College of Food Science and Engineering, Hainan University, Haikou, 570228, China.
Carbohydr Polym. 2021 Apr 15;258:117720. doi: 10.1016/j.carbpol.2021.117720. Epub 2021 Jan 29.
To simplify the process of chitin bio-extraction from shrimp shells powder (SSP), successive co-fermentation using Bacillus subtilis and Acetobacter pasteurianus was explored in this work. Among three protease-producer (B. licheniformis, B. subtilis, and B. cereus), only B. subtilis exhibited high compatibility with A. pasteurianus in co-culture. Successive co-fermentation was constructed as follows: deproteinization was performed for 3 d by culturing B. subtilis in the medium containing 50 g·L SSP, 50 g·L glucose, and 1 g·L yeast extracts; After feeding 5 g·L KHPO and 6 % (v/v) ethanol, A. pasteurianus was cultured for another 2 d without replacing and re-sterilizing medium. Through 5 d of fermentation, the final deproteinization, demineralization efficiency, and chitin yield reached 94.5 %, 92.0 %, and 18.0 %, respectively. This purified chitin had lower molecular weight (12.8 kDa) and higher deacetylation degree (19.6 %) compared with commercial chitin (18.5 kDa, 6.7 %), and showed excellent structural characterization of FESEM and FT-IR analysis.
为简化虾壳粉（SSP）中甲壳素的生物提取过程，本工作探索了枯草芽孢杆菌和巴氏醋酸杆菌的连续共发酵。在三种产蛋白酶菌（地衣芽孢杆菌、枯草芽孢杆菌和蜡样芽孢杆菌）中，只有枯草芽孢杆菌在共培养中与巴氏醋酸杆菌表现出高度的相容性。连续共发酵的构建如下：在含有 50 g·L SSP、50 g·L 葡萄糖和 1 g·L 酵母提取物的培养基中培养枯草芽孢杆菌 3 d 进行脱蛋白；然后，在不更换和重新灭菌培养基的情况下，再培养巴氏醋酸杆菌 2 d，添加 5 g·L KHPO 和 6%（v/v）乙醇。通过 5 d 的发酵，最终脱蛋白率、脱矿率和甲壳素得率分别达到 94.5%、92.0%和 18.0%。与商业甲壳素（18.5 kDa，6.7%）相比，这种纯化的甲壳素有较低的分子量（12.8 kDa）和较高的脱乙酰度（19.6%），并通过 FESEM 和 FT-IR 分析显示出优异的结构特征。
