Abstract :
Accidental leakages of oil during the transportation and other anthropogenic activities results, pollution in environment. Petroleum hydrocarbons are highly toxic to plants animals and humans and they have carcinogenic and mutagenic properties. Bioremediation is as an efficient, economic, versatile and environment friendly technique. The present study is focused to enhance oil degrading ability of bacteria by inducing random mutation using UV radiation. Bacterial strain was isolated from petroleum oil contaminated soil samples. Forty nine oil degrading bacteria were isolated and among them four bacterial isolates (ALK-14, ALK-16, ALK-23 and ALK-35) have shown maximum potential to degrade petroleum hydrocarbon and identified as Alcaligenes species, Bacillus species, Enterobacter species and Corynebacterium species respectively. The pure cultures of these bacterial isolates were subjected to induced mutation at two distance 20cm and 40cm from UV lamp (15W) for different times intervals 20, 40, 60, 80, 100, and 120 sec and it was observed that number of colonies decreased as compare to control depending on exposure time and distance from UV source. The present study mainly focused on petroleum hydrocarbon degradation ability of mutant strains as compared to their wild strains. Mutant strains Alcaligenes species M2 and Corynebacterium species M1 exhibited higher degradation than their wild strains. This study reflects that gene specific mutationenhanced the degradation ability of bacteria and can be employed in bioremediation of petroleum hydrocarbons in soil and water.
Keyword :
Alcaligenes; Corynebacterium, Petroleum hydrocarbon, UV Radiation.