Isolation and identification of indigenous organic acid-producing microorganisms for tungsten dissolution from Hutti gold mine overburden sample

The bio-dissolution possibility of tungsten from a low-grade scheelite bearing Hutti goldmine overburden sample was evaluated using two indigenous microorganisms and the results were compared with that of a laboratory stock Aspergillus niger. A total of fifteen different isolates found in the overburden sample were restricted to two only by using the amplified ribosomal DNA restriction analysis and pH evaluation. These two isolates were identified as Bacillus aryabhattai and Paenibacillus sp. by using the 16S rRNA gene sequencing technique. Upon employing in bioleaching, the microorganisms i.e. B. aryabhattai, Paenibacillus sp., and laboratory stock A. niger could able to leach 24.96 and 4.9 and 88.09 % (w/w) of tungsten from the overburden sample, respectively. The indigenous B. aryabhattai can be preferred for the biodissolution of tungsten over the objectionable fungal bioleaching using A. niger. The indigenous B. aryabhattai showed a new scope for the biotechnology for the purpose of tungsten biodissolution.