A Comparative Analysis of Four Kinds of Polysaccharides Purified from Furcellaria lumbricalis

Four kinds of polysaccharides (FA, FB, FC and FD) were extracted and purified from a red alga Furcellaria lumbri-calis. Their monosaccharide composition, average molecular mass (Mw) and structural feature were determined by gas chromatog-raphy (GC), high performance gel permeation chromatography (HPGPC) and Fourier transform infrared spectroscopy (FTIR), respectively. The results showed that FA and FB were composed of galactose (Gal), 3,6-anhydro-galactose (AnG) and 4-sulfated-galactose (G4S), which were structurally similar to β-carrageenan and κ-carrageenan. FC was composed of sulfated galactose and small amount of AnG, indicating that it was a hybrid-sulfated galactan. FD was composed of α-1, 4-glucose and belonged to floridean starch. The respective yields of FA, FB, FC and FD were 4.84%,33.74%,8.76% and 13.5%, and the cor-responding Mw were 537 kD, 432 kD, 513 kD and 51 kD respectively. Owning to its high content ( >60%) of polysaccharide, F. lumbricalis will be a good source of marine sulfated polysaccharide and shows its potential utilization in food and medicine.

一种蠕虫叉红藻硫酸半乳聚糖的粘度特性研究

探讨红藻多糖在食品中的应用前景，对蠕虫叉红藻（Furcellaria lumbricalis）中1种硫酸半乳聚糖（FB）的粘度特性进行了研究。采用流变仪通过与标准k-卡拉胶（KCA）比较，分析FB在不同温度、pH、金属离子以及酪蛋白存在下粘度的变化。结果表明，在25～50℃下，FB水溶液的粘度随温度升高而迅速下降；在相同温度下，FB水溶液粘度稍受pH值大小的影响；钾离子和钙离子均能降低FB水溶液粘度，但Ca^2＋的加入能明显提高酪蛋白与FB混合水溶液体系粘度。由于FB和KCA粘度变化行为具有相似性，这为FB用作食品添加剂提供了有用数据。