Journal of Petroleum & Environmental Biotechnology

Abstract

Bioremediation Potential of Heavy Metal Multi-Tolerant Pseudomonas Spp. Isolated From a Municipal Waste Dumpsite at Ile-Ife, Osun State, Nigeria

Yetunde M Feruke-Bello*, Olu Odeyemi and Gbolahan O Babalola

Municipal wastes are probable source of heavy metals that may be noxious to the environment and the biotic component due to indiscriminate waste disposal method and open waste dump practiced in Africa.

Three Pseudomonas spp. isolated from a municipal waste dumpsite were evaluated for their tolerance to five metals (Pb, Cd, As, Ni and Cr). The best isolate that showed multiple resistance to all the five metals was identified as Pseudomonas aeruginosa by the 16S rRNA sequence with a Maximum Tolerable Concentrations (MTC) of 2000 mg/l for Pb, 1200 mg/l for Cd, 4500 mg/l for As, 600 mg/l for Ni and 2000 mg/l for Cr. Pseudomonas aeruginosa was subjected to mutation by ethidium bromide and acridine orange; thirteen mutant strains were recovered. The Pseudomonas aeruginosa MutAb, MutAc and MutAe exhibited a 25% increase in the MTC to lead; Pseudomonas aeruginosa MutAa-Ae recorded an improvement of 32% in the MTC to cadmium while Pseudomonas aeruginosa MutAa, MutAb, MutAd and MutAe exhibited 25% increase in the MTC to arsenic after mutational enhancement. All Pseudomonas aeruginosa strains were resistant to all the antimicrobials except for Pseudomonas aeruginosa MutAc which was sensitive to ofloxacin, nitrofurantoin and gentamicin. Pseudomonas aeruginosa MutAe exhibited the removal of 98.9% Pb from solution, compared to the Pseudomonas aeruginosa wild type with 97.4% at pH 7.

The outcome of the research specifies that the efficiency of native microbes in bio-removal procedure can be boosted by mutation for effective bioremediation of effluents with Pb metal contaminations.

Published Date: 2023-12-04; Received Date: 2023-11-02