枸杞多糖的组成分析及其荧光标记研究

Studies on Separation and Fluorescent Labeling of Lycium barbarum Polysaccharides

目的研究枸杞多糖的组成分析,并设计荧光标记的枸杞多糖,为研究体内代谢提供受试品。方法采用膜分离技术提取枸杞多糖,Sevage法脱蛋白,并通过紫外光谱分析、红外光谱分析、离子色谱分析等方法对枸杞多糖进行组成研究。同时,以异硫氰酸荧光素作为荧光探针合成荧光标记的枸杞多糖,用荧光分光光度计测定其荧光取代度。结果所提取的枸杞多糖是一种水溶性的蛋白多糖,组分较为单一,总糖含量为81.58%。红外光谱分析其具有糖类的特征吸收峰。枸杞多糖中主要含有阿拉伯糖、氨基半乳糖、半乳糖和葡萄糖四种单糖,其中葡萄糖含量最高。异硫氰酸荧光素通过与枸杞多糖的共价偶联,实现对枸杞多糖的荧光标记,荧光取代度为1.3%,并且标记后的枸杞多糖体外稳定性在24 h内良好。结论首次实现了枸杞多糖的荧光标记,并且其体外稳定性良好,为以后研究代谢动力学提供良好的荧光探针。

Objective To study the separation of Lycium barbarum polysaccharides（ LBP）,and design the labeled LBP. It can provide subjects for metabolic studies in vivo. Methods LBP were separated from Lycium barbarum by membrane separation technology and deproteinised by means of sevage. The separation of LBP was determined by means of UV-Vis,IR and Ion chromatography analysis. Meanwhile,we chose Fluorescein-isothiocyanate（ FITC） to label LBP,and fluorescent substitute ratio is detected by fluorescence spectrophotometer. Results LBP as water-soluble proteoglycans,isolated and extracted from Lycium barbarum fruits. Its separation was single and the content of total sugar was 81. 58%. IR analysis indicated that LBP have the characteristic absorption peak of saccharides. Ion chromatography analysis showed that the monosaccharides in LBP were arabinose,aminogalactose,galactose and glucose and the glucose content was the highest. Through covalent attached to LBP,FITC realize the fluorescent labeling of LBP and the fluorescence degree of substitution was 1. 3%. The labeled LBP＇s stability in vitro was well in24 h. Conclusion The research was the first time to label LBP and the result showed that labeled LBP was stable in vitro. So it could be a fluorescent probe to further study the Pharmacokinetic profiles.