Comparative Study on the Composition and in vitro Antioxidant Activity of Polysaccharide in Different Wuyi Mingcong Tea Germplasms
To explore the differences in the composition and in vitro antioxidant activities of tea polysaccharides from different Wuyi Mingcong tea germplasms,the fresh leaves of four Wuyi Mingcong including Queshe,Guazijin,Yanzhiliu and Laojunmei were selected as raw materials.Tea polysaccharides were prepared by water extraction and alcohol precipitation method.The contents of neutral sugars,uronic acids,proteins and tea polyphenols in tea polysaccharides were determined,and the scavenging activities of four tea polysaccharides on DPPH free radical,hydroxyl radical and superoxide anion free radical were compared.The results show that the yields of tea polysaccharides extracted from fresh leaves of different Wuyi Mingcong were different.The yield of tea polysaccharides from Yanzhiliu was the highest,and the yield of polysaccharides from Laojunmei tea was the lowest.There were significant differences in the basic composition of neutral sugars,uronic acids,proteins and tea polyphenols among the four Wuyi Mingcong tea germplasms.The results of in vitro antioxidant activities of tea polysaccharides show that the scavenging activities of DPPH free radical,hydroxyl radical and superoxide anion radical of different Wuyi Mingcong tea germplasms were significantly different,and the scavenging abilities of four kinds of tea polysaccharides to three kinds of free radicals show a dose-effect relationship.The IC50 values for scavenging DPPH free radical and superoxide anion free radical of the four kinds of tea polysaccharides were higher than that of the positive control Vc,and the IC50 values for scavenging hydroxyl free radical were lower than that of the positive control Vc.The results show that the tea polysaccharides of the four germplasms had good hydroxyl free radical scavenging abilities.Our results can provide scientific basis for the de-velopment and utilization of Wuyi Mingcong tea germplasm resources and the breeding of functional tea cultivars.
万方数据
维普
