Institute of Food Science and Technology, College of Biological Science and Engineering, Fuzhou University, 350108 Fuzhou, China; Fujian Center of Excellence for Food Biotechnology, 350108 Fuzhou, China.
Institute of Food Science and Technology, College of Biological Science and Engineering, Fuzhou University, 350108 Fuzhou, China.
Food Chem. 2021 Oct 30;360:129967. doi: 10.1016/j.foodchem.2021.129967. Epub 2021 Apr 27.
Due to the hindrance of flocculated polymers and bacterial cell wall, the production of Bacillus subtilis using monosodium glutamate byproduct (MSGB) was low. With the assistance of scanning electron microscope images, effects of alkali, lysozyme, papain, ultrasound, and their combinations on MSGB were evaluated using the results of soluble protein, carbohydrate, monosaccharides and peptidoglycans. Alkali could dissolve flocculated polymers increasing 21% soluble MSGB, and thus enhanced the subsequent treatments (ultrasound, lysozyme, or papain) to increase 14-17% soluble MSGB. As ultrasound mainly released intercellular components (mannose, and glucose) while lysozyme or papain mainly released cell wall components (peptidoglycans), the combination of alkali, ultrasound, and enzymes led to a highest soluble MSGB (78%), yielding a maximal B. subtilis production of 6.6 × 10 colony-forming units mL. This yield was about 33 times that of using untreated MSGB, and the key to improve B. subtilis production was the release of carbohydrate.
由于絮凝聚合物和细菌细胞壁的阻碍，使用味精副产物 (MSGB) 生产枯草芽孢杆菌的产量较低。通过扫描电子显微镜图像，用可溶性蛋白质、碳水化合物、单糖和肽聚糖的结果评价了碱、溶菌酶、木瓜蛋白酶、超声及其组合对 MSGB 的作用。碱可以溶解絮凝聚合物，使可溶性 MSGB 增加 21%，从而增强后续处理（超声、溶菌酶或木瓜蛋白酶），使可溶性 MSGB 增加 14-17%。由于超声主要释放胞内成分（甘露糖和葡萄糖），而溶菌酶或木瓜蛋白酶主要释放细胞壁成分（肽聚糖），因此碱、超声和酶的组合导致可溶性 MSGB 最高（78%），枯草芽孢杆菌的产量达到 6.6×10 个菌落形成单位 mL。该产量约为使用未经处理的 MSGB 的 33 倍，提高枯草芽孢杆菌产量的关键是碳水化合物的释放。
