Isolation and Characterization of Iron and Sulfur Oxidizing Bacteria from Coal Mines

Abstract

The present study is aimed at to isolate the sulfur and iron oxidizing bacteria that can be used to remove the pollutant like as FeSO_4; MgSO₄ etc. Four bacterial isolates were isolated from coal samples called from Choa Saidan Shah, Punjab, Pakistan (Sp3¹_, Sp4¹_, Sp5³ and Sp6²) evaluated on the basis of biochemical and morphological tests. Most of the isolates showed medium sized colonies with round shape, irregular margin, creamy in color expect Sp6² formed yellow colored colonies. All the strains were Gram +ve rods and Spore former, Motile, Catalase producers, Starch hydrolyzing, Nitrate reducer except the SP6². Strains SP3¹ and SP4¹ were sensitive against (Ampicillin-300 µg ml^-1, Tetracycline 25 µg ml^-1, Streptomycin 500 µg ml^-1, Chloramphenicol 5 µg ml^-1) antibiotics. Maximal growth was observed at pH 7.0 except SP5³ at pH 5.0, the optimum temperature was 42°C except SP5³at 37°C. After sequencing analysis as Bacillus subtilis (SP3¹), Bacillus subtilis (SP4)¹, Pseudomonas sp (SP5³) and Stenotrophomonas (SP6²) respectively were identified. So these isolates can be exploited for bioremediation of coal.

Keywords: Bacillus subtilis, Pseudomonas sp, Stenotrophomonas, bioremediation, coal, sulfur.