Abstract：
Exopolysaccharides (EPSs) are naturally occurring high-molecular-weight carbohydrates that have been widely studied for their biological activities, including antioxidant, immunomodulatory, anticancer and gut microbiota regulation activities. Polysaccharides are abundant in nature and can be derived from animals, plants, algae, and microorganisms, but among polysaccharides with potential uses, EPSs from microorganisms have the advantages of a short production cycle, high yield, and independence of production from season and climate and thus have broad prospects. While the safety of the producing microorganism can represent a problem in application of microbial EPSs, lactic acid bacteria (LAB) have been used by humans for thousands of years, and they and their products are generally recognized as safe. This makes LAB excellent sources for exopolysaccharides. EPS-producing LAB are readily found in nature. Through screening of strains, optimization of culture conditions, and improvement of the growth medium, the yield of EPSs from LAB can be increased and the scope of application broadened. This review summarizes EPSs from LAB in terms of structure, function and applications, as well as yield optimization, and introduces recent research on the biological activities and practical applications of LAB EPSs, aiming to provide references for researchers in related areas.
摘要：
胞外多糖（EPS）是天然存在的高分子量碳水化合物，已被广泛研究其生物活性，包括抗氧化剂，免疫调节,抗癌和肠道菌群调节活性。多糖在自然界中含量丰富，可以从动物中提取，植物,藻类,和微生物，但是在具有潜在用途的多糖中，来自微生物的EPS具有生产周期短的优点，高产,以及生产与季节和气候的独立性，因此具有广阔的前景。虽然生产微生物的安全性可能代表微生物EPS应用中的问题，乳酸菌（LAB）已经被人类使用了数千年，他们和他们的产品通常被认为是安全的。这使得LAB成为胞外多糖的优异来源。产生EPS的LAB容易在自然界中发现。通过菌株的筛选,优化培养条件，和生长培养基的改进，可以提高LAB的EPS的产率，并扩大应用范围。这篇综述从结构方面总结了LAB的EPS，功能和应用，以及产量优化，并介绍了近年来有关LABEPS的生物活性和实际应用的研究，旨在为相关领域的研究者提供参考。
