Improvement of chromium biosorption through protoplast electrofusion between Candida tropicalis and Candida lipolytica  

作　　者：何宝燕 尹华 杨峰 叶锦韶 彭辉 卢显妍 张娜 

机构地区：[1]Department of Environmental Engineering,Jinan University [2]Key Laboratory of Water/Soil Toxic Pollutants Control and Bioremediation of Guangdong Higher Education Institutes(Ji'nan University)

出　　处：《Journal of Central South University》2012年第6期1693-1701,共9页中南大学学报（英文版）

基　　金：Project(NSFC-GDNSF U0933002) supported by the Joint Funds of the National Natural Science Foundation of China and the Natural Science Foundation of Guangdong Province,China;Project(50978122) supported by the National Natural Science Foundation of China

摘　　要：Protoplasts from Candida tropicalis and Candida lipolytica were fused under an optimized electrofusion （electrical pulse strength 6 kV/cm, pulse duration time 40μs and pulse times 5） and then regenerated on YEPD media for achieving new genotypes with higher chromium loading capacity. A target fusant RHJ-004 was screened out by its chromium resistance and chromium-sorbing capacity tests for further research. The comparative study of applicability shows that the fusant has better performance than its parent strains in respect of solution pH, biomass concentration and chromium loading capacity. Especially for treating low concentration Cr（VI） （〈20 mg/L）, above 80% chromium is sequestered from the aqueous phase at pH 1-9. Atomic force microscopy （AFM） visualizes the distribution of chromium on the binding sites of the cells, suggesting that the altered surface structure and intracellular constitutes of the fusant associate with its increased biosorption capacity. The rapid biosorption processes of chromium foUow the Langmuir model well.Protoplasts from Candida tropicalis and Candida lipolytica were fused under an optimized electrofusion(electrical pulse strength 6 kV/cm,pulse duration time 40 μs and pulse times 5) and then regenerated on YEPD media for achieving new genotypes with higher chromium loading capacity.A target fusant RHJ-004 was screened out by its chromium resistance and chromium-sorbing capacity tests for further research.The comparative study of applicability shows that the fusant has better performance than its parent strains in respect of solution pH,biomass concentration and chromium loading capacity.Especially for treating low concentration Cr(VI)(≤20 mg/L),above 80% chromium is sequestered from the aqueous phase at pH 1-9.Atomic force microscopy(AFM) visualizes the distribution of chromium on the binding sites of the cells,suggesting that the altered surface structure and intracellular constitutes of the fusant associate with its increased biosorption capacity.The rapid biosorption processes of chromium follow the Langmuir model well.

关 键 词：CHROMIUM BIOSORPTION FUSANT PROTOPLAST ELECTROFUSION 

分 类 号：X703[环境科学与工程—环境工程]