The utilization and speciation transformation of α-S8 and μ-S by the typical mesophilic acidophilic strain Acidithiobacillus ferrooxidans ATCC 23270 were investigated.A.ferrooxidans cells first acclimated to the ene...The utilization and speciation transformation of α-S8 and μ-S by the typical mesophilic acidophilic strain Acidithiobacillus ferrooxidans ATCC 23270 were investigated.A.ferrooxidans cells first acclimated to the energy source α-S8 or μ-S,respectively.The results of cell growth and sulfur oxidation behavior showed that the strain grown on α-S8 entered slowly（about 1 d later） into the exponential phase,while grew faster in the exponential phase and attained higher maximal cell density and lower p H value than that on μ-S.After bio-corrosion,both of the two sulfur samples were evidently eroded and modified by A.ferrooxidans cells.After growth of A.ferrooxidans,the surface composition of amorphous μ-S became 63.1% μ-S and 36.9% α-S8,and that of orthorhombic α-S8 became 68.3% α-S8 and 31.7% μ-S,while the surface compositions of α-S8 and μ-S in sterile experiment were not changed,indicating that these two elemental sulfur species can be interconverted by A.ferrooxidans.展开更多
The bioleaching of pyrite and biosolubilization of rock phosphate （RP） in 9K basal salts medium were compared by the following strains of an autotrophic acidophilic bacterium, Acidithiobacillus ferrooxidans, a heter...The bioleaching of pyrite and biosolubilization of rock phosphate （RP） in 9K basal salts medium were compared by the following strains of an autotrophic acidophilic bacterium, Acidithiobacillus ferrooxidans, a heterotrophic acidophilic bacterium, Acidiphilium cryptum, and mixed culture of At. ferrooxidans and A. cryptum. The results show that A. cryptum is effective in enhancing the bioleaching of pyrite and biosolubilization of RP in the presence of At. ferrooxidans, although it could not oxidize pyrite and solubilize RP by itself. This effect is demonstrated experimentally that A. cryptum enhances a decrease in pH and an increase in redox potential, concentration of total soluble iron and planktonic part bacterial number in the broth during pyrite bioleaching processes by At. ferrooxidans. The mixed culture of At. ferrooxidans and A. cryptum leads to the most extensive soluble phosphate released at 30 °C. Pulp density exceeding 3% is shown to adversely influence the release of soluble phosphate by the consortium of At. ferrooxidans and A. cryptum. It is essential to add pyrite to the 9K basal salts medium for the biosolubilization of RP by the mixed culture of At. ferrooxidans and A. cryptum, and the percentage of soluble phosphate released is the greatest when the mass ratio of RP to pyrite is 1：2 or 1：3.展开更多
基金Project(51274257)supported by the National Natural Science Foundation of ChinaProject(U1232103)supported by the Joint Funds of National Natural Science Foundation of China and Large Scientific Facility Foundation of Chinese Academy of SciencesProject(VR-12419)supported by the Beijing Synchrotron Radiation Facility Public User Program
文摘The utilization and speciation transformation of α-S8 and μ-S by the typical mesophilic acidophilic strain Acidithiobacillus ferrooxidans ATCC 23270 were investigated.A.ferrooxidans cells first acclimated to the energy source α-S8 or μ-S,respectively.The results of cell growth and sulfur oxidation behavior showed that the strain grown on α-S8 entered slowly（about 1 d later） into the exponential phase,while grew faster in the exponential phase and attained higher maximal cell density and lower p H value than that on μ-S.After bio-corrosion,both of the two sulfur samples were evidently eroded and modified by A.ferrooxidans cells.After growth of A.ferrooxidans,the surface composition of amorphous μ-S became 63.1% μ-S and 36.9% α-S8,and that of orthorhombic α-S8 became 68.3% α-S8 and 31.7% μ-S,while the surface compositions of α-S8 and μ-S in sterile experiment were not changed,indicating that these two elemental sulfur species can be interconverted by A.ferrooxidans.
基金Project(51004078)supported by the National Natural Science Foundation of ChinaProject(NCET-11-0965)supported by the Program for New Century Excellent Talents in University,China+2 种基金Project(2012FFA101)supported by the Natural Science Foundation of Hubei Province,ChinaProject(IRT0974)supported by the Program for Changjiang Scholars and Innovative Research Team in University,ChinaProject(2011CB411901)supported by the National Basic Research Program of China
文摘The bioleaching of pyrite and biosolubilization of rock phosphate （RP） in 9K basal salts medium were compared by the following strains of an autotrophic acidophilic bacterium, Acidithiobacillus ferrooxidans, a heterotrophic acidophilic bacterium, Acidiphilium cryptum, and mixed culture of At. ferrooxidans and A. cryptum. The results show that A. cryptum is effective in enhancing the bioleaching of pyrite and biosolubilization of RP in the presence of At. ferrooxidans, although it could not oxidize pyrite and solubilize RP by itself. This effect is demonstrated experimentally that A. cryptum enhances a decrease in pH and an increase in redox potential, concentration of total soluble iron and planktonic part bacterial number in the broth during pyrite bioleaching processes by At. ferrooxidans. The mixed culture of At. ferrooxidans and A. cryptum leads to the most extensive soluble phosphate released at 30 °C. Pulp density exceeding 3% is shown to adversely influence the release of soluble phosphate by the consortium of At. ferrooxidans and A. cryptum. It is essential to add pyrite to the 9K basal salts medium for the biosolubilization of RP by the mixed culture of At. ferrooxidans and A. cryptum, and the percentage of soluble phosphate released is the greatest when the mass ratio of RP to pyrite is 1：2 or 1：3.
