Optimization of Culture Condition for Biosorption of Lead using Pseudomonas aeruginosa isolated from Gold Mining Site of Anka, Zamfara State

Abstract

Pseudomonas aeruginosa was used as a biosorbent for biosorption of lead from heavy metal contaminated gold mining soil of Anka, in Zamfara State. The effects on the degree of biosorption by Pseudomonas aeruginosa were studied: these include Contact time, pH, Temperature, Biomass load and Agitation speed. The effects of contact time were studied at 24, 48, and 72h. Results show highest uptake (98.3%) of lead at 48h and the least (97.8%) at 24h. Effect of pH studied at pH 3, 4, 5, 6, and 7, with pH 6 recording the highest lead removal of 99.0% while pH 3 recorded the least percentage biosorption. The effect of Temperature was studied at 25, 35, 45, 55, and 650C, the highest percentage biosorption (99.3%) recorded at 55⁰C and the lowest 98.1%) was at both 35 and 45⁰C. Effect of biomass load was studied using different volumes (0.5, 1.0, 1.5, 2.0, and 2.5ml) of the innoculum: generally the values obtained did not show variation with change in biomass load. Effect of agitation speed was studied at 2000, 2500, and 3000rpm; the highest lead removal was at 2000 rpm. Biosorption of heavy metals is an excellent technology and represents a potentially cost-effective way for heavy metal decontamination from the environment.