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

摘要:

【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。

Abstract:

[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 60Co 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 O2- 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 60Co 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.