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

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.

Key words:Resistance to 60Co gamma rays, Erwinia sp., Identification, Polysaccharide, Antioxidant activity