Isolation and Identification of Filamentous Fungi F54 and Its Biosorption and Enrichment Characteristics of Cesium

In order to obtain indigenous strains with radionuclide remediation ability in radioactive pollution area in Xinjiang, soil samples were collected for separation of microorganisms. After the pressure tests and adsorption experiments, a filamentous fungus F54 was finally obtained. Through the traditional morphology and molecular biology identification, strain F54 belongs to Fusarium sp., exhibits the highest homology with Fusarium oxysporum strain ATCC MYA-3931. The optimum growth condition is: potato dextrose medium, pH=7.0. The optimum absorption conditions of Cs⁺ for F54 strain are: pH=7.0, 30 ℃, 3-4 d associated with the growth. The Cs⁺ adsorption efficiency of F54 can up to be about 84% tested by ICP-MS. Common cations such as K⁺, Na⁺, Ca²⁺, Mg²⁺, Al³⁺, Fe³⁺ can inhibit the adsorption of Cs⁺. The F54 strain can tolerate 10 kGy dose irradiation of radioactive cobalt, and also has high tolerance of heavy mental ions Ni²⁺, Cr³⁺, Zn²⁺, Co²⁺, Pb²⁺, Hg²⁺. The adsorption efficiency of radioactive ¹³⁷Cs can up to be 62% tested by liquid scintillator. Strain F54 has high potential to repair radioactive pollution in heavy metal contaminated environment.