Abstract: (6973 Views)
Background and purpose: Selenium is important as a key trace element which is required by
most organisms in biology. Despite its importance in cellular functions, high concentrations of selenium,
particularly in the forms of selenate and selenite are highly toxic. Therefore, it is necessary to perform
biogeochemical studies and develop strategies for the effective control of toxic oxyanion of selenate in
the environment.
Material and Methods: In this study, 30 strains were isolated from industrial wastewater in
Qom Province using the enrichment culture technique and direct plating on agar. MIC of sodium selenite
was measured by agar dilution method and also, antibiogram test was performed for resistant strains
Results: Bacterial strains designated QW4 and QW184 (Qom Wastewater Number 4 and 184)
exhibited very high MIC values (760 and 700, respectively) for toxic oxyanion of selenate. Conventional
biochemical tests and 16S rRNA studies identified QW4 and QW184 as Proteus hauseri (FR733709-1) and
Escherichia coli (AJ567606). These two bacterial strains were resistant to some antibiotics.
Conclusion: Enrichment culture technique was found to be more useful than direct plating on
agar for isolation of selenate resistant bacteria. QW4 and QW184 could be used for bioremediation of
contaminated sites.