干燥方法对瘤背石磺多糖抗氧化性和还原力的影响

Effects of drying methods on antioxidant activities and reducing capacity of polysaccharides extracted from Onchidium struma

以瘤背石磺为原料,采用传统的水提醇沉法提取瘤背石磺多糖,研究真空冷冻干燥和烘箱干燥两种方式对多糖抗氧化活性的影响。以Vc作为阳性对照,通过清除DPPH自由基、·OH、O_2^-·和亚硝酸盐来检测多糖的抗氧化活性,用分光光度法检测其总还原力。结果表明,瘤背石磺的冻干多糖比烘干多糖具有更高的抗氧化活性,冻干多糖对DPPH自由基、·OH和亚硝酸盐的IC50分别为4.14,2.96,2.05mg/mL,清除率与多糖浓度呈明显的量效关系;但是两种多糖的总还原力不强,对O_2^-·基本没有清除能力;在同等浓度下,多糖的抗氧化活性均弱于Vc。

The polysaccharide of Onchidium struma was extracted by using traditional hot water extraction and alcohol precipitation meth- od,the influence of vacuum freeze drying and oven drying on the an- tioxidant activity of polysaccharides was investigated. The antioxidant activities of the polysaccharide was evaluated by scavenging DP- PH free radical, hydroxyl free radical, surperoxide anion radical and sodium nitrite, and the total reducing capacity of polysaccharide was studied by spectrophotometric method. The results showed that the scavenging effect of freeze dried polysaccharide was stronger than the oven dried polysaccharide, the IC5o for scavenging activities against DPPH free radical, hydroxyl and sodium nitrite were 4.14, 2.96 and 2.05 mg/mL,whieh showed the relationship to close-dependence,but the polysaccharide had little scavenging effect on surperoxide anion radical, and the reducing capacity was weak. The antioxidant activities of two polysaccharides were weaker than Vc under the same con- centration.