The Isolation,Purification,Identification and Study on Biological Activities of Lycium Barbarum Polysacchuride

Lycium Barbarum(LB) was extracted by hot water,precipated by ETOH to obtain crude polysaccharide of LB, which was then treated by the method of proteinase digestion,Sevag method and dialysis to obtain LBP.Polyacrylamide tested by electrophoresis showed no obvious protein band.The quantitative test of protein by Brandford method exhibited no protein existing (5μg protein/mg polysaeeharide).The LBP was further purified by Sephadex G-50,two components were isolated:LBP1 (MW10000) and LBP2 (MW10000).Pigment was removed from LBP1 and LBP2 by DEAE- DE32 ion- exchange chromatography.Ultraviolet spectra analysis displayed no protein or nucleic acid.Infrared spectra analysis of LBP,LBP1 and LBP2 showed that there was characteristic polysaccharide absorption peak.The molecular weights of LBP1 and LBP2 were 35400 and 9900 respectively.Experiments in vitro and in vivo demonstrated that LBP, LDP1 and LBP2 had bi-direetion modulating effect on the proliferation of T lymphocytes of the mice spleens.They could increase the proliferation of ConA- stimulated T lymphocytes.LBP2 could significantly increased the number of mouse spleen antibody forming cell against SRBC,which indicated that LBP2 enhanced the function of humoral immunity of mice,it also had antagonistic effect on radiation-damage and significantly prolong the survival time of BALB/c mice.