屎肠球菌JT_1的抗氧化特性

The oxidation resistance of enterococcus faecium JT_1

检测课题组前期分离鉴定得到的屎肠球菌JT_1(Genebank登录号:KM233626)的体外抗氧化能力。以样品对超氧阴离子(O_2·)、羟自由基(HO·)、亚铁离子(Fe^(2+))和1.1-二苯基苦基苯肼(DPPH)的清除率为指标,对其抗氧化性进行定性及定量研究。经研究发现,屎肠球菌JT_1的无细胞提取物和菌体细胞对O_2·、HO·、Fe^(2+)和DPPH都有一定的清除能力,其中屎肠球菌JT_1的无细胞提取物对超氧阴离子(O_2·)的清除率为6.132%,对羟自由基(HO·)的清除率为72.772%,对亚铁离子(Fe^(2+))的螯合率为95.523%,对DPPH的清除率为8.281%;其菌体细胞对超氧阴离子(O_2·)的清除率为17.246%,对羟自由基(HO·)的清除率为25.940%,对亚铁离子(Fe^(2+))的螯合率为50.110%,对DPPH的清除率为23.873%。研究表明,屎肠球菌JT_1的无细胞提取物对HO·和Fe^(2+)有较强的清除能力;其菌体细胞对HO·和Fe^(2+)的清除能力也很强,对O_2·和DPPH的清除能力比无细胞提取物更强。这一结论证实了屎肠球菌JT_1的抗氧化特性,为其在功能性食品中的应用提供了有力的理论依据。

To detect the in vitro antioxidant capacity of enterococcus faecium JT1（Genebank accession number： KM233626）. Enterococcus faecium JT1 was isolated and identified in our laboratory. The antioxidant properties of superoxide anion（O2·）, hydroxyl free radical（HO·）, ferrous ion（Fe2＋） and DPPH were measured and studied qualitatively and quantitatively. The study found that enterococcus faecium JT1 cell-free extracts and cells had certain ability to scavenge O2·, HO·, Fe2＋ and DPPH. Under advisement enterococcus faecium JT1 cell-free extracts on superoxide anion（O2·） removal rate was 6.132%, the hydroxyl radical（HO·） scavenging rate of 72.772%, ferrous ion（Fe2＋） chelating rate was 95.523%, the DPPH clearance rate was 8.281%. And for the bacteria cells the clearance rate of superoxide anion（O2·） was 17.246%, the scavenging rate of hydroxyl radical（HO·） was about 25.940%, the chelate rate of ferrous ion（Fe2＋） was about 50.110%, the clearance rate of DPPH was 23.873%. By contrast, no cell extracts of enterococcus faecium JT1 had strong scavenging capacity of HO· and Fe2＋; the bacteria cells on the scavenging ability of HO· and Fe2＋ was also very strong, but the O2· and DPPH scavenging capacity was strongger than the cell-free extracts. This conclusion confirmed the antioxidant properties of enterococcus faecium JT1, and provided a strong theoretical basis for its application in functional foods.