Abstract:
This study evaluates the microbial remediation of industrial wastewater (effluent) from a pharmaceutical company in Akure, Nigeria. The ability of the isolated bacteria in the effluent were assessed over a 15 day period. Those with the highest pollutant removal ability were selected for bioremediation study as individual pure culture and as various consortia. Bioremediation was studied in terms of change in physicochemical concentrations of biological oxygen demand (BOD), chemical oxygen demand (COD), total dissolved solids (TDS), total nitrogen and total phosphorous. The total bacterial counts ranged from 2.6 × 107Cfu/ml to 2.7 × 107Cfu/ml on nutrient agar. Bacterial isolate in the industrial wastewater include Bacillus paramycoides strain OFAh, Bacillus paramycoides strain OFAg Streptococcus faecalis, Providencea rettgeri, Klebsiella pneumoniae, Escherichia coli and Citrobacter freundii. B. paramycoides strain OFAg and B. paramycoides strain OFAh showed higher industrial wastewater pollutant removal ability. The bacterial cell count reduced to 35.00 ± 0.50 × 104 Cfu/mL and 29.50 ± 0.50 x 104 Cfu/mL for the two strains used following bioremediation. Bacillus paramycoides strain OFAg and B. paramycoides strain OFAh normalized the pH of the wastewater from weakly acidic 6.90 ± 0.01 to alkaline value of 8.46 ± 0.04 and 8.23 ± 0.01 respectively, conforming to WHO standard. The values of COD and BOD of the industrial wastewater reduced (p<0.05) when treated with B. paramycoides strain OFAg (37.98% and 21.76%) respectively. For TDS, Bacillus paramycoides strain OFAg caused a reduction of 60.89%, while B. paramycoides strain OFAh reduced the solid concentration by 63.12%. Bacillus paramycoides strain OFAg achieved 60.19% and 50.00% while B. paramycoides strain OFAh achieved 55.16% and 61.92% in nitrogen and phosphorus concentration and 50.00% and 61.92% in phosphorus concentration reduction respectively.
