一株耐辐射新菌种的分离鉴定及其多糖的抗氧化研究

Isolation and identification of a new radiation-tolerant species and the antioxidant of its polysaccharides

【目的】确定新疆辐射污染土样中分离筛选获得的一株产多糖的耐辐射菌株W36-1的分类学地位和抗氧化特性。【方法】对该菌株进行的60Co辐照,结合菌落形态和菌丝特征显微观察、Biolog鉴定以及16S rRNA基因序列分析。采用苯酚硫酸法测定其多糖含量,采用Fenton法测定多糖的粗提物对超氧阴离子清除率;用DPPH法测定抗氧化性;采用邻苯三酚自氧化法测定对超氧阴离子的清除率。【结果】W36-1可耐5 kGy辐照,为一株欧文氏菌属(Erwinia)新种;其粗多糖含量为53.17%,该多糖对超氧阴离子清除率为75.63%,对DPPH清除率为62.43%,羟基自由基去除率为54.89%。【结论】菌株W36-1产的多糖具有抗氧化性。

[Objective] The taxonomic status and antioxidant properties were studied on the radiation resistant strain W36-1 producing polysaccharide from the radiation-tainted soil of Xinjiang. [Methods] The strain W36-1 with the 6~Co gamma rays irradiation was classified in combination with characteristics of hyphae of colony morphology and microscopic observation and Biolog appraisal and the analysis of the 16S rRNA gene sequences. Phenol-sulfuric acid method was employed to determine polysaccharide contents, the polysaccharides on 02- scavenging effect were measured by the Fenton method, the anti-oxidative effects of extracts were studied by using DPPH and pyrogallol autooxidation methods. [Results] The strain W36-1 was a novel species as genera Erwinia, and it could survive at 5 kGy of the 60o gamma rays irradiation. The crude polysaccharide content was 53.17%, its polysaccharide to the ultra oxygen anion clearance rate was 75.63%, the DPPH clearance rate was 62.43%, the hydroxyl free radical removal rate was 54.89%. [Conclusion] The polysaccharide from the strain W36-1 has the antioxidant capacity.