食品工业科技2012，Vol.33Issue(16)：118-121,4.
Escherichia coli K5胞外多糖硫酸酯衍生物的制备及其体外抗氧化活性研究
Preparation and antioxidant activities of a sulfated derivative of exopolysaccharide from Escherichia coil K5
摘要
Abstract
Escherichia coil K5 strain was cultivated by fermentation,the supernatant was treated by ultrafiltration, exopolysaccharide（EPS） was extracted by ethanol precipitation,and then purified by Sevage method,dialysis, freeze-dried, DEAE-Sepharose and Sephadex G-75 column,finally high-purity K5 polysaccharide（K5） was obtained. N site of the K5 polysaccharide was chemically sulfated by Sulfur trioxide pyridine complex,NS-K5 polysaccharide（NS-K5） was prepared,and disaccharide analysis revealed that N-sulfation rate was up to 57%. The antioxidant capacity of K5 polysaccharideand N-sulfated K5 polysaccharide was investigated,the results showed that within a certain concentration range,the reducing activity of NS-K5 was powerful over K5, when the concentration of K5 and NS-K5 was up to lmg/mL,the hydroxyl radical scavenging rates were 17.7% ,25.6% ,and DPPH radical scavenging rates were 26.1% ,45% ,respectively. The result indicated that NS-K5 showed stronger antioxidant activity than K5.关键词
大肠杆菌K5/胞外多糖/硫酸酯/抗氧化活性Key words
Escherichia coli K5/exopolysaccharide/sulfation/antioxidation分类
轻工纺织引用本文复制引用
王华,徐静静,曹凤,陈敬华..Escherichia coli K5胞外多糖硫酸酯衍生物的制备及其体外抗氧化活性研究[J].食品工业科技,2012,33(16):118-121,4.基金项目
国家自然科学基金 （）
教育部新世纪优秀人才计划 （）
