Yenepoya Research Centre, Yenepoya University, University Road, Deralakatte, Mangalore, India.
Int J Biol Macromol. 2019 Jun 15;131:10-18. doi: 10.1016/j.ijbiomac.2019.03.048. Epub 2019 Mar 7.
Marine bacteria secrete exopolysaccharides (EPS) with unique structural and functional properties and serve as a source of newer bioactive biopolymers. This study reports an EPS produced by a marine bacterium identified as Alteromonas sp. PRIM-28 for its bioactivities. The EPS was characterised using standard methods and tested for its bioactivities using in vitro models. EPS-A28 is an anionic heteropolysaccharide with a molecular weight of 780 kDa and exists as triple helical structure in aqueous solution. Monosaccharide composition is mannuronic acid, glucose and N-acetyl glucosamine repeating units in the ratio 1:3.67:0.93. The FT-IR spectra showed the presence of sulphate, phosphate and uronic acid residues. The thermal analysis showed partial degradation of the EPS-A28 at 190 °C and 40% of residues were stable up to 800 °C. It showed biocompatibility and induced proliferation and migration of dermal fibroblasts (HDF) and keratinocytes. EPS-A28 could increase the S-phase of cell cycle. The proliferative property of the EPS-A28 was established by the increased expression of fibroblast proliferation marker (Ki-67) also its capability of binding to cell surface. It also induced nitric oxide and arginase synthesis in macrophages. These findings suggest that EPS-A28 can be potentially used as a multifunctional bioactive polymer in wound care.
海洋细菌分泌具有独特结构和功能特性的胞外多糖 (EPS)，是新型生物活性生物聚合物的来源。本研究报告了一种由海洋细菌 Alteromonas sp. PRIM-28 产生的 EPS，因其生物活性而被鉴定。使用标准方法对 EPS 进行了表征，并使用体外模型对其生物活性进行了测试。EPS-A28 是一种阴离子杂多糖，分子量为 780 kDa，在水溶液中存在于三螺旋结构中。单糖组成是甘露糖醛酸、葡萄糖和 N-乙酰葡萄糖胺重复单元，比例为 1:3.67:0.93。FT-IR 光谱显示存在硫酸盐、磷酸盐和糖醛酸残基。热分析表明 EPS-A28 在 190°C 时部分降解，40%的残留物在 800°C 时稳定。它表现出生物相容性，并诱导真皮成纤维细胞 (HDF) 和角质形成细胞的增殖和迁移。EPS-A28 可以增加细胞周期的 S 期。通过增加成纤维细胞增殖标志物 (Ki-67) 的表达及其与细胞表面结合的能力，确定了 EPS-A28 的增殖特性。它还能诱导巨噬细胞中一氧化氮和精氨酸酶的合成。这些发现表明，EPS-A28 可以作为一种多功能生物活性聚合物，潜在地用于伤口护理。
