 Cyanidation is a relatively simple and cheap technology to treat gold-containing ores. However, this process is not completely effective in refractory gold-bearing sulfide ores. In the case of very low-grade ores, biooxidation is an attractive alternative pre-treatment to render the gold amenable to extraction. This process utilizes the ability of acidophilic bacteria to oxidize the sulfide m...

A cross-comparison of six strains isolated from two different regions, Chambishi copper mine (Zambia, Africa) and Dexing copper mine (China, Asia), was conducted to study the leaching efficiency of low grade copper ores. The strains belong to the three major species often encountered in bioleaching of copper sulfide ores under mesophilic conditions: Acidithiobacillus ferrooxidans, Acidithiobaci...

in this research work, the zinc extraction was investigated, using bioleaching process from a low grade zinc concentrate which was produced from the accumulated flotation tailings. zinc content was initially upgraded to 11.97% by flotation process. bioleaching experiments were designed and carried out by a mixed culture of acidithiobacillus ferrooxidans, acidithiobacillus thiooxidans, leptospir...

The whole genome of a pigment-producing isolate from a lake in northern India, Pseudogulbenkiania ferrooxidans strain EGD-HP2, has been sequenced to study the spectrum of biosynthesis of secondary metabolites. The genome annotation data revealed an operon for violacein, which showed homology with the reported operon of a Chromobacterium sp., and also a quinone cofactor.

Microorganisms are dominant form of life on the Earth. It is necessary to enlarge the knowledge about them for more efficient use in all areas of biotechnology, medicine, ecology. Acidithiobacillus ferrooxidans are acidophilic chemolitoautothropfic bacteria, with capability to oxidize ferrous ions and used in waste water, tail gas treatment and bioleaching technologies. In appropriate condition...

The recovery of metal values and safe disposal of spent catalyst is gaining interest due to both its hazardous nature and increased regulation associated with disposal methods. Prior to the recovery of the valuable metals, removal of entrained deposits limit the diffusion of lixiviate resulting in low recovery of metals must be taken into consideration. Therefore, petroleum refinery spent catal...

The genome of Thiobacillus ferrooxidans ATCC 19859 is about 2.8 X 10(6) base pairs as determined by analysis of reassociation kinetics of sheared DNA. This is 70% of the size of the genome of Escherichia coli. About 6% of the genome of T. ferrooxidans consists of moderately repetitive DNA sequences that are repeated an average of 20 times per genome. Two distinct repeated sequences, designated ...

sulfur emission from coal combustion presents many environmental problems. the techniques used to reduce the amount of sulfur in coal before combustion, include physical, chemical and biological processes.biological processes based on degradation of sulfur compounds by microorganisms offer many advantages over the conventional physical and chemical processes. the processes are performed under m...