Li Wentian, Guo Yilin, Chen Haiming, Chen Wenxue, Zhang Hailing, Zhang Ming, Zhong Qiuping, Chen Weijun
College of Food Sciences & Engineering, Hainan University, Haikou 570228, China.
Maritime Academy, Hainan Vocational University of Science and Technology, Haikou 571126, China.
Gels. 2021 Sep 28;7(4):156. doi: 10.3390/gels7040156.
The present study aimed to evaluate the rheological and interfacial behaviors of a novel microbial exopolysaccharide fermented by (LSEP). The structure of LSEP was measured by LC-MS, H and C NMR spectra, and FT-IR. Results showed that the monosaccharide composition of LSEP was D-mannose (8.53%), D-glucose (79.25%), D-galactose (7.15%), and L-arabinose (5.07%); there existed the anomeric proton of α-configuration and the anomeric carbon of α- and β-configuration; there appeared the characteristic absorption peak of the phosphate ester bond. The molecular weight of LSEP was 401.8 kDa. The water holding capacity (WHC, 2.10 g/g) and oil holding capacity (OHC, 12.89 g/g) were also evaluated. The results of rheological properties showed that the aqueous solution of LSEP was a non-Newtonian fluid, exhibiting the shear-thinning characteristics. The adsorption of LSEP can reduce the interfacial tension (11.64 mN/m) well and form an elastic interface layer at the MCT-water interface. Such functional properties make LSEP a good candidate for use as thickener, gelling agent, and emulsifier to form long-term emulsions for food, pharmaceutical, and cosmetic products.
本研究旨在评估由[具体菌种]发酵产生的一种新型微生物胞外多糖（LSEP）的流变学和界面行为。通过液相色谱-质谱联用（LC-MS）、氢核磁共振（¹H NMR）、碳核磁共振（¹³C NMR）光谱以及傅里叶变换红外光谱（FT-IR）对LSEP的结构进行了测定。结果表明，LSEP的单糖组成为D-甘露糖（8.53%）、D-葡萄糖（79.25%）、D-半乳糖（7.15%）和L-阿拉伯糖（5.07%）；存在α构型的端基质子以及α和β构型的端基碳；出现了磷酸酯键的特征吸收峰。LSEP的分子量为401.8 kDa。还评估了其持水能力（WHC，2.10 g/g）和持油能力（OHC，12.89 g/g）。流变学性质结果表明，LSEP水溶液为非牛顿流体，具有剪切变稀特性。LSEP的吸附能够很好地降低界面张力（11.64 mN/m），并在中链甘油三酯-水界面形成弹性界面层。这些功能特性使LSEP成为用作增稠剂、胶凝剂和乳化剂以形成用于食品、药品和化妆品的长效乳液的良好候选物。
