Optimization Of Conditions For Preparation Of Active Component RG-I-4 From Ginseng Pectin

Panax ginseng C.A.Meyer is traditional medicine in China,One of the active components including ginseng polysaccharides.Ginseng polysaccharides are composed of starch-like glucans and pectin.Ginseng pectin is composed of different types of structural domain,Like rhamonogalacturonan type I(RG-I),rhamonogalacturonan type II(RG-II),homogalacturonan(HG)and so on.Our lab has isolated a RG-I domain of pectin,namely RG-I-4.It founds that RG-I-4 had strong inhibitory activity on Galectin-3.Since the different strains and origins of ginseng,there are some differences in the structure and the content of RG-I-4.In addition,the preparation and purification of RG-I-4 are more complicated and with a longer time.Therefore,in order to stabilized,simpled,fast accessed to the active component of ginseng pectin of RG-I-4,This paper optimized the methods.The conclusions of this paper were as follows:First,Ginseng polysaccharide samples were separated and purificated by Diethylaminoethyl-cellulose and then obtained ginseng pectine(WGPA).WGPA was a kind of brown powder with yield of 18.2%.The sugar content of and uronic acid content of WGPA was 82.8% and 39.4%,respectively.Its molecular weight distribution was very wide indicating,it's a kind of polysaccharide mixture.Its monosaccharide composition was GalA(40%),Glc(19.9%),Ara(15.6%),Rha(7.9%),Gal(15%),and Man(1.7%).As the pre-method according to lab,WGPA was hydrolysed by Endo-PG,the production was isolated by Sephadex G-25 colume and DEAE Sepharose Fast Flow colume to get RG-I-4 with yield of 1.4%,Its monosaccharide composition shows that Rha/GalA was 0.67,Its molecular weight is 67 kDa,It had strong inhibitory activity on Galectin-3 mediated by hemagglutination,the minimum inhibition concentration was 0.25±0.05 ug/mL.Optimization of hydrolysis and preliminary separation of production and purification of WGPA-UD.WGPA was hydrolysised by Endo-PG,detect the production of reducing sugar and WGPA-UD to optimized the amount of enzyme,enzyme hydrolysis' s time and the times of hydrolysis.The hydrolysis conditions of WGPA was Optimized that enzyme amount is 30 mg/g,times of hydrolysis is 2,each time for 2 h.The optimized condition of preliminary separation of production is dialysis.WGPA-UD was classificated by DEAE Sepharose Fast Flow to optimized,It shows that it eluted by 0.22 M NaCl and 0.3 M NaCl,the points eluted by 0.3 M NaCl is RG-I-4.RG-I-4 was prepared by optimized condition with yield of 1.5%,Its monosaccharide composition shows that Rha/GalA was 0.69,Its molecular weight is 70 kDa,It had strong inhibitory activity on Galectin-3 mediated by hemagglutination,the minimum inhibition concentration was 0.3 ug/mL,It shows that the RG-I-4 was prepared by optimized condition was up to standard.The results show that using the optimized conditions can be simple,fast and much more to get the active component RG-I-4.