College of Food Science, Shenyang Agricultural University, Shenyang 110866, PR China.
College of Foreign Language, Shenyang Agricultural University, Shenyang 110866, PR China.
Int J Biol Macromol. 2020 Aug 15;157:36-44. doi: 10.1016/j.ijbiomac.2020.04.150. Epub 2020 Apr 24.
An exopolysaccharide (EPS)-producing strain SN-8 isolated from Dajiang was identified as Leuconostoc mesenteroides. When sucrose was used as the carbon source for fermentation, the output of EPS was 2.42 g/L. High performance liquid chromatography analysis confirmed the presence of monomers such as glucan and mannose. The molecular weight detection value is 2.0 × 10 Da. Fourier transform infrared spectroscopy displayed the EPS had the basic skeleton and functional groups of a typical polysaccharide structure. Scanning electron microscopy showed smooth surfaces and compact structure. Thermal performance analysis showed that the highest heat resistance temperature of the EPS was 80 °C. Compared with vitamin C, its hydroxyl radical scavenging rate was as high as 32% and 1,1-diphenyl-2-picrylhydrazyl scavenging rate was as high as 40% under the same concentration. The peanut oil was the most emulsifiable at a concentration of 1.5 mg/mL, and the emulsification index was 0.55. These results might show that the EPS had high application value.
一株从大姜中分离到的产胞外多糖（EPS）的菌株 SN-8 被鉴定为肠膜明串珠菌。当蔗糖作为发酵的碳源时，EPS 的产量为 2.42 g/L。高效液相色谱分析证实了存在葡萄糖和甘露糖等单体。分子量检测值为 2.0×10 Da。傅里叶变换红外光谱显示 EPS 具有典型多糖结构的基本骨架和官能团。扫描电子显微镜显示其表面光滑，结构紧凑。热性能分析表明，EPS 的最高耐热温度为 80°C。在相同浓度下，其对羟基自由基的清除率高达 32%，对 1,1-二苯基-2-苦基肼的清除率高达 40%。在 1.5 mg/mL 的浓度下，花生油的乳化效果最好，乳化指数为 0.55。这些结果可能表明 EPS 具有很高的应用价值。
