化橘红多糖的提取纯化及抗氧化活性研究

对化橘红粗多糖及其纯化组分的抗氧化活性进行研究。化橘红粉末经热水提取、乙醇沉淀、sevage法脱蛋白、透析得到粗多糖,粗多糖经DEAE-52纤维素阴离子交换层析柱分离,得到2个纯化组份ECP1和ECP2。采用化学法分别测定了粗多糖及其纯化组分的体外清除自由基(DPPH.,.OH,ABTS.+)能力、还原能力。粗多糖的多糖含量为74.29%,经DEAE-52纯化的组分ECP1和ECP2的多糖含量分别为83.39%和85.77%。结果表明粗多糖及其两个纯化组分均具有较好的抗氧化清除自由基的能力,并且抗氧化能力与多糖浓度之间存在良好的相关性。其中ECP2的抗氧化清除自由基能力强于ECP和ECP1,但是低于对照VC。

Extraction, purification and antioxidant activity ofpolysaccharide from exocarpium citri grandis

The antioxidant activity of crude polysaccharide and its purified fractions from exocarpium citri grandis （ECP） was investigated. Crude polysaccharide of exocarpium citri grandis was extracted by boiling water. The filtrated polysaecharide was precipitated by alcohol. The protein in ECP was removed by Sevage method. The small molecular impurities were removed by dialysis. Two purified polysaccharides ECPI and ECP2 were obtained from crude ECP by DEAE-52 anion-exchange chromatography. Furthermore, the antioxidant activities of the crude ECP in vitro and its pu- rified fractions were evaluated by determinations of their reducing power and scavenging activities on 1,1-Diphenyl-2-picrylhydrazyl free radicals （DPPH~）, hydroxyl radicals （-OH）, 2, 2-biphenyl-double （3-ethyl benzene and Margaret lin-6-sulfonic acid radicals （ABTS.＋）. The polysaccharide contents ofECP, ECP1 and ECP2 were 74.29%, 83.9% and 85.7%, respectively. Crude polysaccharide and its purified fractions had good antioxidant activities, and their antioxidant activities were significantly correlated with their concentrations. Our results suggest that the antioxidant activity of ECP2 is higher than those of ECP1 and ECP, but is lower than the activity of VC.