Heavy metal (As, Cd, Cr, Hg, Pb) analysis and identification of heavy metal resistant bacteria in sediments from Manado Bay

Abstract

Environmental pollution from heavy metals is becoming a growing concern due to the adverse effects it is causing throughout the world. This study aims to analyze heavy metal concentrations and identify heavy metal resistant bacteria in the bay of Manado. Sediment samples were collected from five bays in Manado. The concentrations of heavy metals As, Cd, Cr, Hg and Pb were analyzed using ICP-OES, and Hg using CV-AFS. Bacteria from the sediment were grown in nutrient broth media containing heavy metals As, Cd, Cr, Hg and Pb respectively. Microbiology and 16SrRNA gene analysis were used to identify the bacteria that grown on media containing varying concentrations of heavy metals. The results showed that the sediments from the five bays in Manado contained heavy metals with an average concentration of As <1mg/kg, Cd 1.8mg/kg), Cr 6.2mg/kg, Hg <0.07mg/kg). and Pb 11.2mg/kg. The results of microbiological and molecular analysis showed that 5 species of heavy metal resistant bacteria were Pseudomonas aeruginosa, Bacillus cereus, Staphylococcus arlettae, Acinobacter sp., and Brevibacterium sp. The five bacteria found to be resistant to heavy metals can be used to detoxify As, Cd, Cr, Hg, and Pb.