羊栖菜多糖提取条件优化及其抗氧化活性的研究

Optimization of extraction process of Sargassum fusiforme polysaccharide and antioxidant activity

本文采用响应面方法对羊栖菜多糖提取工艺进行了优化,通过超滤膜(MW分别为100000、50000、10000和5000 u)将羊栖菜多糖分进行分离,并对不同分子量段羊栖菜多糖的抗氧化活性进行了分析。在微波功率为385 W时,微波辅助水提法提取羊栖菜多糖的较优工艺条件为:液料比34 m L/g,微波时间8 min,水提温度95℃,提取时间2.1 h,在此条件下,羊栖菜多糖得率为11.51%±0.12%;不同分子量段羊栖菜多糖均具有较强的抗氧化能力,对羟自由基、超氧阴离子、DPPH自由基均有一定程度上的清除作用,SFPSⅤ(MW≤5000 u)自由基清除能力优于SFPSⅠ、SFPSⅡ、SFPSⅢ和SFPSⅣ。在一定范围内,羊栖菜多糖对羟自由基、DPPH自由基清除率超过50%,自由基清除率均随多糖浓度的增加而增强。研究将为羊栖菜多糖的高效利用提供理论指导。

The extraction process of Sargassum fusiforme polysaccharide was optimized by response surface methodology. The polysaccharide fraction of Sargassum fusiforme was separated by ultrafihration membrane （ MW = 100000,50000,10000 and 5000 u）, of which the antioxidant activities were studied.When microwave power was 385 W, the microwave-assisted extraction of polysaccharide from Sargassum fusiforme was as follows ： the ratio of liquid to material was 34 mL/g, microwave time was 8 min, extraction temperature was 95 ℃, extraction time was 2.1 h, and the yield of polysaccharide was 11.51% ± 0.12%. Under the experiment, the polysaccharide of Sargassum fusiforme had strong antioxidant ability in scavenging hydroxyl radical, superoxide anion and DPPH＂ free radical, and the ability of SFPS V （ MW ≤ 5000 u ） in scavenging free radical was stronger than SFPS Ⅰ, SFPS Ⅱ, SFPS Ⅲ and SFPS Ⅳ. Radical scavenging rate of hydroxyl radical, DPPH. free radical were more than 50%. Free radical scavenging rate increased with the increasing of polysaccharide concentration. This study will provide theoretical guidance for efficient utilization of Sargassum fusiforme polysaccharide.