Microbial origin polysaccharides have gained popularity due to lesser toxicity, better degradability and selectivity as compared to their synthetic counterparts and can be used as emulsifier, stabilizer, thickener, texturizer, flocculating and gelling agent. Here main emphasis on exopolysaccharide production from potential lactic acid bacteria that has GRAS status. This work was aimed at isolating, purifying and characterizing an extracellular polysaccharide (EPS) produced by a foodgrade lactic acid bacteria Lactobacillus paraplantarum KM1. L. paraplantarum KM1 was isolated from human milk and identified by conventional and molecular techniques. The 16S rRNA sequence of the isolate was registered in National Centre for Biotechnology Information (NCBI) under accession number KX671558. L. paraplantarum KM1 was found to produce EPSs in lactose containing MRS medium, and the maximum yield (47.4 mg/ml) was achieved after 32-h incubation. As evident from TLC and HPLC analyses, the polysaccharide was found to be a heteropolymer-containing glucose, galactose and mannose as main sugars. Different oligosaccharides namely hexoses were obtained after partial hydrolysis of the polymer using MALDI-ToF-MS. The total molecular weight of all polysaccharides present was 348.7 kDa with 100 °C thermal stability as well as water soluble in nature. Cell cytotoxicity revealed that the purified EPS was safe for consumption; thus, it can be used in various food industries as emulsifying and texture agent. The present study highlighted that exopolysaccharides could be harnessed to improve food products in terms of texture, emulsifying agents, pharmaceutical industry (antioxidants, antitumour, anti-inflammatory and antiviral agents) and as safety purposes.

中文翻译：

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从人乳中分离的副植物乳杆菌KM1产生的新型胞外多糖的纯化，表征及其细胞毒性

与它们的合成对应物相比，微生物来源的多糖由于其毒性较小，降解性和选择性更好而受到欢迎，并且可以用作乳化剂，稳定剂，增稠剂，膨化剂，絮凝剂和胶凝剂。这里主要强调具有GRAS地位的潜在乳酸菌的胞外多糖生产。这项工作旨在分离，纯化和鉴定食品级乳酸菌副植物乳杆菌KM1产生的细胞外多糖（EPS）。从人乳中分离副植物乳杆菌KM1，并通过常规和分子技术鉴定。分离株的16S rRNA序列已在国家生物技术信息中心（NCBI）注册，登录号为KX671558。L. 发现副植物KM1在含乳糖的MRS培养基中产生EPS，并且在孵育32小时后达到最大产量（47.4 mg / ml）。从TLC和HPLC分析可以明显看出，该多糖是一种包含葡萄糖，半乳糖和甘露糖作为主要糖的杂聚物。使用MALDI-ToF-MS对聚合物进行部分水解后，获得了不同的低聚糖，即己糖。存在的所有多糖的总分子量为348.7 kDa，具有100°C的热稳定性以及天然水溶性。细胞的细胞毒性表明纯化的EPS可以安全食用。因此，它可以在各种食品工业中用作乳化剂和质感剂。本研究强调，胞外多糖可用于改善食品的质地，乳化剂，