Tian Juanjuan, Mao Qingyan, Dong Mingsheng, Wang Xiaomeng, Rui Xin, Zhang Qiuqin, Chen Xiaohong, Li Wei
College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China.
Foods. 2021 Nov 12;10(11):2780. doi: 10.3390/foods10112780.
Soybean whey is a high-yield but low-utilization agricultural by-product in China. In this study, soybean whey was used as a substrate of fermentation by 70810 strains. An exopolysaccharide (LPEPS-1) was isolated from soybean whey fermentation by 70810 and purified by ion-exchange chromatography. Its preliminary structural characteristics and antioxidant activity were investigated. Results show that LPEPS-1 was composed of mannose, glucose, and galactose with molar ratios of 1.49:1.67:1.00. The chemical structure of LPEPS-1 consisted of →4)-α-D-Glc-(1→, →3)-α-D-Gal-(1→ and →2)-α-D-Man-(1→. Scanning electron microscopy (SEM) revealed that LPEPS-1 had a relatively rough surface. In addition, LPPES-1 exhibited strong scavenging activity against DPPH and superoxide radicals and chelating ability on ferrous ion. This study demonstrated that soybean whey was a feasible fermentation substrate for the production of polysaccharide from 70810 and that the polysaccharide could be used as a promising ingredient for health-beneficial functional foods.
大豆乳清是中国一种产量高但利用率低的农业副产品。在本研究中，大豆乳清被用作70810菌株的发酵底物。从70810菌株发酵的大豆乳清中分离出一种胞外多糖（LPEPS - 1），并通过离子交换色谱法进行纯化。对其初步结构特征和抗氧化活性进行了研究。结果表明，LPEPS - 1由甘露糖、葡萄糖和半乳糖组成，摩尔比为1.49:1.67:1.00。LPEPS - 1的化学结构由→4)-α-D-葡萄糖-(1→、→3)-α-D-半乳糖-(1→和→2)-α-D-甘露糖-(1→组成。扫描电子显微镜（SEM）显示LPEPS - 1表面相对粗糙。此外，LPPES - 1对DPPH和超氧自由基具有较强的清除活性以及对亚铁离子的螯合能力。本研究表明，大豆乳清是70810菌株生产多糖的可行发酵底物，且该多糖可作为有益健康的功能性食品的一种有前景的成分。
