| Coix lachryma-jobi kernel(Coix lachryma-jobi[L]var.frumentacea Makino),is a special economical resource in Fujian,which has rich nutrition and special health value.Extraction technology,Isolation and purified technology,Level structure and the anti-oxidantive effect of Coix lachryma-jobi kernel polysaccharide were studied. Therefore,basic data for development of Coix lachryma-jobi kernel polysaccharide were offered.(1)The best extraction technology of soluble polysaccharide in Jiasha Coix lachryma-jobi kernel was studied.On the basis of single-factor experiments,the optimum extraction technology was determined through orthogonal experiments:the solidliquid ratio 1:40,extracting time 4hr,extracting temperature 95℃,the extraction rate reached to 1.44%.(2)The best isolation technology of soluble polysaccharide in Jinsha Coix lachryma-jobi kernel was studied.On the basis of the comparison of three methods,it was determined that the optimum method was enzymolysis technique.The optimum isolation technology through rotational-regression experiment:the enzymolysis temperature 40℃,pH value 7,the enzyme concentration 5682μ/g.The dynamic equation:Y=61.49872+5.95511X3-2.44231X12-1.03977X22-1.83703X32+1.11612X1X2(3)The crude polysaccharide of Coix lachryma-jobi kernel was extracted in water,removed proteins by Sevag's methods,and was isolated and purified by SephadexG-75.White powder State objects was obtained after freeze-drying,and the pure Coix lachryma-jobi kernel polysaccharide was identified by Waters 2695 HPLC. The result showed that pure polysaccharide is soluble in water,insoluble in alcohol, ether,acetone and other organic solvents and has thermal stability.The polysaccharide liquid is approximate pH 7.0 and the polysaccharide would degradate under acid or alkali condition,the Coix lachryma-jobi kernel polysaccharide is a pure polysaccharide which doesn't contain protein.(4)According to the analysis of IR fingerprint characteristics absorption,the result showed that the Coix lachryma-jobi kernel polysaccharide is an acidic polysaccharide containing a carboxyl.In addition,the results of 867.75cm-1 department absorption peak and 1H-NMR showed that the configuration of polysaccharide isβ-glycosidic.According to 13C- NMR,the Coix lachryma-jobi kernel polysaccharide contains six monosaccharide residues,and has characteristic absorption peaks of xylose methyl,HPLC and GC analysis showed that glyconeutral sugars consist of L-rhamnose,L-arabinose,D-glucose,D-galactose,D-xylose and D-mannose.Besides these,observed surface morphology by Fluorescence microscope, the analysis showed that the particle takes the shape of cloud cluster,with a distribution of filamentary.Coix lachryma-jobi kernel polysaccharide has a molecular weight of 2993,[α]D20=+155°(0.151,H2O)and[η]=0.313.(5)The effect on scavenging·OH and·O2-of Coix lachryma-jobi kernel polysaccharide were studied by Fenton system and Pyorgallol Autoxidation Method respectively,which was compared with the effect of tea polyphenols.The result showed that the Coix lachryma-jobi kernel polysaccharide could effectively scavenge·OH and·O2- in the experimental range,and the polysaccharide had stronger scavenging ability on·OH and lower ability on·O2- compared with tea polyphenols. Moreover,the purified polysaccharide had stronger scavenging ability than the crude polysaccharide.
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