【摘要】 采用水提醇沉法提取金花茶叶多糖,并采用DEAE-纤维素阴离子交换法对其进行分级纯化,获得TPS1、TPS2、TPS3 3个级分;通过凝胶色谱法、PMP柱前衍生高效液相色谱法、傅里叶红外光谱法对TPS1、TPS2、TPS3的分子量、单糖构成及微观结构进行分析,并研究其体外抗氧化性。结果表明:TPS1主要由葡萄糖、半乳糖、阿拉伯糖构成,而且是由两种不同分子量(1.55×10~5,1.05×10~4 Da)多糖组成的杂多糖;TPS2与TPS3主要由鼠李糖、半乳糖醛酸、半乳糖、阿拉伯糖构成,而且二者为单一组分的均一多糖,平均分子量分别为4.21×10~5,6.67×10~5 Da;傅立叶红外光谱分析表明,3种金花茶多糖级分的异头碳连接方式均为β-构型;各级分金花茶多糖均具有一定的自由基清除作用,且存在量效关系,其中糖醛酸含量最高的酸性多糖TPS3体外抗氧化活性最佳,说明金花茶多糖的抗氧化活性与其结构组成相关。综上,金花茶多糖具有潜在的抗氧化活性。更多还原

【Abstract】 The polysaccharide of Camellia Nitidissima Chi was extracted by water extraction and alcohol precipitation, and the polysaccharide was purified by DEAE cellulose anion exchange classification to obtain TPS1, TPS2 and TPS3;The molecular weight, monosaccharide composition and microstructure of TPS1, TPS2 and TPS3 were analyzed by gel permeation chromatography, pre-column PMP derivatization and HPLC and fourier transform infraredspectrometer(FTIR), and the antioxidant activity of TPS1, TPS2 and TPS3 were studied in vitro. The results were described as followed. TPS1 was mainly composed of glucose, galactose and arabinose, and was a heteropolysaccharide composed of two polysaccharides with different molecular weights(1.55×10~5, 1.05×10~4 Da).TPS2 and TPS3 were mainly composed of rhamnose, galacturonic acid, galactose and arabinose, and they were homogeneous polysaccharides with the average molecular weight of 4.21×10~5 Da and 6.67×10~5 Da, respec-tively. Fourier transform infrared spectrometer(FTIR) showed that the heterocarbon-connected modes of three polysaccharide fractions were β-configuration. In addition, the polysaccharides of different levels of Camellia Nitidissima Chi had certain free radical scavenging effects, and there was a dose-effect relationship. Among them, TPS3 with the highest content of uronic acid had the best antioxidant activity in vitro, indicating that the antioxidant activity of Camellia Nitidissima Chi polysaccharide was related to its structural and composition. In conclusion, the polysaccharide of Camellia Nitidissima Chi had potential antioxidant activity.更多还原