Departamento de Bioquímica e Biologia Molecular, Universidade Federal do Ceará, CP 12.200, CEP 60455-760 Fortaleza, Ceará, Brazil.
Carbohydr Polym. 2013 Jan 30;92(1):598-603. doi: 10.1016/j.carbpol.2012.09.009. Epub 2012 Sep 14.
Seaweeds are considered an important source of bioactive molecules. In this work the marine red alga Gracilaria caudata was submitted to aqueous extraction of their polysaccharides for 2 h at 100 °C. The polysaccharide fraction (PGC) presented a recovery of 32.8%. The sulfate content of PGC, calculated by S%, is 1 ± 0.2% and the degree of sulfation accounts for 0.13 ± 0.2. High-Performance Size-Exclusion Chromatography demonstrated that PGC consists of a high molecular weight polysaccharide (2.5 × 10(5)gmol(-1)). Chemical analysis of PGC was performed by microanalysis, infrared (FT-IR) and nuclear magnetic resonance (NMR, 1 and 2D) spectroscopy. The structure of PGC is mainly constituted by the alternating residues 3-linked-β-D-galactopyranose and 4-linked-3,6-α-L-anhydrogalactose; however some hydroxyl groups were substituted by methyl groups and pyruvic acid acetal. The biological precursor of 3,6-α-L-anhydrogalactose (6-sulfate-α-l-galactose) was also detected.
海藻被认为是生物活性分子的重要来源。在这项工作中，将海洋红藻石花菜在 100°C 下用热水提取 2 小时以提取其多糖。多糖部分（PGC）的回收率为 32.8%。PGC 的硫酸根含量（按 S%计算）为 1±0.2%，硫酸化程度为 0.13±0.2。高效体积排阻色谱表明，PGC 由高分子量多糖（2.5×10(5)gmol(-1))组成。通过微量分析、红外（FT-IR）和核磁共振（NMR，1 和 2D）光谱对 PGC 进行了化学分析。PGC 的结构主要由交替的 3 位连接的β-D-半乳糖和 4 位连接的 3,6-α-L-脱水半乳糖残基组成；然而，一些羟基被甲基和丙酮酸缩醛取代。还检测到 3,6-α-L-脱水半乳糖（6-硫酸-α-l-半乳糖）的生物前体。
