Heavy Metal Tolerance Profile among Bacteria from Auto-mechanic Workshop and Pristine Soil

Abstract

The study was aimed at investigating the heavy metal tolerance profile among bacteria from auto-mechanic workshop and pristine soil samples. Auto-mechanic workshop and pristine soil environments were randomly sampled within Calabar Metropolis. The research was undertaken within a period of six months. Standard microbiological methods were used to isolate, characterize and identify bacteria isolates from the collected soil samples, while heavy metal tolerance test of the bacteria isolates was carried out using agar dilution method. Bacterial isolates from auto-mechanic workshop soil samples showed a marginally higher percentage tolerability to Pb, Ni, Cr, Cd, Co and V than their pristine soil counterparts. Serratia spp (AMM2, AMME2), Klebsiella sp (AMM3), Corynebacterium (AME1), Yesinia sp (AME3), Pseudomonas sp (AMT) and Bacillus sp (AME4) tolerated high heavy metal concentration (300 µg/ml) of chromium, copper and lead either actively (bioaccumulation) or passively (adsorption) as compared to other bacteria isolates from both auto-mechanic workshop and pristine soil samples. Thus, these bacteria isolates could have applicability in bioremediation of heavy metal polluted environments and in the production of biosensors which can be utilized for both background and anthropogenic environmental heavy metal pollution.