Abstract：
Alginates are industrially relevant polysaccharides widely used in the food and biomedical industries for their excellent gelling properties. The growing emphasis on the valorization of marine resources has evidenced the need for alternative methods for the determination of both alginate content and the M/G ratio. This study describes the application of acid methanolysis and separation by anion exchange chromatography. Five samples, including alginates extracted from Saccharina latissima, Ascophyllum nodosum, a certified standard, and two poly-uronates (Poly-M and Poly-G), were analysed for their M/G ratio and alginate content at different treatment conditions, and compared with other conventionally used or reference methods (NMR, FTIR, and colorimetric methods). Quantitative estimation of alginate was relatively accurate at optimum conditions (4 h at 100 °C), as compared with the certified standard or with other colorimetric methods. M/G ratios were not significantly different from those determined after the reference method (1H NMR) or compared to FTIR protocols. The results evidence that methanolysis may be applied to simultaneously estimate the purity and M/G ratio of alginate-rich samples in a single analysis.
摘要：
藻酸盐是工业相关的多糖,由于其优异的胶凝性质而广泛用于食品和生物医学工业。越来越重视海洋资源的增值，这证明了对确定藻酸盐含量和M/G比的替代方法的需求。这项研究描述了酸甲醇分解和阴离子交换色谱分离的应用。五个样本,包括从糖精中提取的藻酸盐，夜蛾，经过认证的标准，和两种聚糖醛酸酯（聚M和聚G），分析了它们在不同处理条件下的M/G比和藻酸盐含量，并与其他常规使用或参考方法(NMR，FTIR,和比色法)。在最佳条件下（100°C下4小时），藻酸盐的定量估算相对准确，与认证标准或其他比色法相比。M/G比与参考方法（1HNMR）后测定的或与FTIR方案相比的M/G比没有显着差异。结果证明，甲醇分解可用于在一次分析中同时估算富含藻酸盐的样品的纯度和M/G比。
