中文摘要：

研究了江蓠琼胶寡糖的抗氧化活性及其对罗非鱼肉的保鲜作用。首先,以酶法制备的江蓠琼胶寡糖为研究对象,通过测定江蓠琼胶寡糖对DPPH自由基、ABTS~＋自由基、·OH自由基的清除能力,研究江蓠琼胶寡糖的抗氧化活性。其次,以p H值、TVB-N值、TBA值及菌落总数为指标研究江蓠琼胶寡糖对罗非鱼肉的保鲜作用。研究表明,江蓠琼胶寡糖具有较强的抗氧化活性,且聚合度为3的寡糖的抗氧化活性最高。经寡糖溶液浸泡后的罗非鱼肉在保鲜过程中的p H值、TBA值、TVB-N值及细菌总数均低于空白对照组,因此,江篱琼胶寡糖能有效减缓罗非鱼肉中蛋白质腐败,降低脂肪氧化速率,减少细菌滋生,从而提高保鲜期限,延长罗非鱼的货架期。

英文摘要：

The antioxidant activity of Gracilaria agaro oligosaccharides prepared by enzyme hydrolysis method was detected by measuring the scavenging capacity of agaro oligosaccharides on DPPH, ABTS＋and ·OH. Thus, the effect of Gracilaria agaro oligosaccharides on Tilapia preservation was studied by determining the variation of p H, TVB-N, thiobarbituric acid（TBA） and total bacteria. The results showed that Gracilaria agaro oligosaccharides had strong antioxidant activity and remarkably the agarooligosaccharides with degree of polymerization 3 had the best antioxidant activity. Moreover, after soaking with the oligosaccharide solution, the Tilapia revealed a lower level of p H, TBA, TVB-N and bacterial count than that in the control group in the down the Tilapia protein corruption, reduce the rate of fat oxidation, decrease the growth of bacteria, thus improve the preservation period and extend the shelf life of Tilapia.