Strains of bacteria with the ability of utilizing glyphosate as the sole source of carbon were isolated from soil exposed to glyphosate herbicide by culture enrichment method and identified through partial 16S rRNA gene sequence analysis. Sixteen different microbial strains were isolated from glyphosate-contaminated sites in Kubau local govt. area, Kaduna state. Two of the microbial strains: BBDD3 and BBD4 were found to be the best degraders and were able to withstand up to 16.4 mg/ml of the glyphosate concentration. On the basis of 16s rRNA and biochemical tests, BBDD3 and BBDD4 strains were identified as Escherichia coli and Sporanaerobacter acetigenes respectively. These strains demonstrate laboratory utilizing ability of 92% and 98% for 16.4 mg/ml of the glyphosate formulation, respectively. The best optimum conditions for degradation were observed at pH 6.0 for the strains and at the temperature of 35oC for strain BBDD3 and BBDD4. Based on these results, the two strains displayed their potentials to be used in the bioremediation of glyphosate-contaminated environment.
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