Publications (3)0.73 Total impact
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Article: Bioleaching of soluble phosphorus from rock phosphate containing pyrite with DES-induced Acidithiobacillus ferrooxidans
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ABSTRACT: The effects of Acidithiobacillus ferrooxidans (At. f) mutated with diethyl sulfate (DES) as a mutagen on the bioleaching of soluble phosphorus (P) from rock phosphate (RP) were investigated. The results show that the oxidative activity of At. f is greatly improved by 1.0% (volume fraction) of DES. Correspondingly, the highest leaching rate of soluble P is also obtained to be 14.9% by the At. f mutated, which is 85.8% higher than that of the adapted At. f without mutation. In addition, the SEM images are significantly performed that the corrosion of RP residue surfaces leached by 1.0% DES-induced At.f is much worse than that of leached by the adapted At. f. All the above indicate that the leaching efficiency of soluble P from RP with pyrite can be greatly improved by using DES-induced At. f to a certain extent.Journal of Central South University of Technology 04/2012; 16(5):758-762. · 0.36 Impact Factor -
Article: Characterization of tricalcium phosphate solubilization by Stenotrophomonas maltophilia YC isolated from phosphate mines
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ABSTRACT: The phosphate solubilizing characteristics of a strain YC, which was isolated from phosphate mines (Hubei, China), were studied in National Botanical Research Institute’s phosphate (NBRIP) growth medium containing tricalcium phosphate (TCP) as sole phosphorus (P) source. The strain YC is identified as Stenotrophomonas maltophilia (S. maltophilia) based upon the results of morphologic, physiological and biochemical characteristics and 16S rRNA sequences analysis. The results show that the strain S. maltophilia YC can solubilize TCP and release soluble P in NBRIP growth medium. A positive correlation between concentration of soluble P and population of the isolate and a negative correlation between concentration of soluble P and pH in the culture medium are observed from statistical analysis results. Moreover, gluconic acid is detected in the culture medium by HPLC analysis. It indicates that the isolate can release gluconic acid during the solubilizing experiment, which causes acidification of the culture medium and then TCP solubilization. S. maltophilia YC has a maximal TCP solubilizing capability when using maltose as carbon source and ammonium nitrate as nitrogen source, respectively, in NBRIP growth medium.Journal of Central South University of Technology 04/2012; 16(4):581-587. · 0.36 Impact Factor -
Article: Optimization for rock phosphate solubilization by phosphate-solubilizing fungi isolated from phosphate mines
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ABSTRACT: The optimization for rock phosphate (RP) solubilization by phosphate-solubilizing fungi (Candida krissii, Penicillium expansum and Mucor ramosissimus) isolated from phosphate mines (Hubei, PR China) was investigated. The content of soluble phosphorus (P) released by these isolates was tested on the National Botanical Research Institute's phosphate growth medium (NBRIP) containing RP as sole P source. Results showed that the optimum conditions were at temperature, 32 °C; shaking speed, 160 rpm; RP concentration, 2.5 g l−1; EDTA concentration, 0.5 mg ml−1. The content of soluble P gradually decreased with a larger particle size of RP with all the isolates. The content of soluble P was the highest when the initial pH for RP solubilization was 5.5 in the medium inoculated with C. krissii, which was different from that of 7.0 in the medium inoculated with P. expansum and 7.5 in the medium inoculated with M. ramosissimus. All the isolates showed lower tolerance with increasing concentration of silver ion (Ag+). Moreover, the highest content of soluble P was achieved when released by C. krissii at 20 of C:N ratio, P. expansum at 40 of C:N ratio and M. ramosissimus at 30 of C:N ratio.Ecological Engineering.
