Biodegradation of Crude Oil Using Marine <i>Bacillus species</i> from Vadinar Coast, Gujarat, India

Abstract

The marine environment is open to large sources of toxic organic waste in the form of accidental oil spills. Therefore, it is important to study microbial degradation processes that help reduce the damage caused to the environment. Universally, oil spills produce enormous public anxiety and highlight the need for costeffective, indigenous and environmentally acceptable bioremediation technologies. In recent times, advanced remedial techniques have been opted, such as solidifying, skimming, controlled burning and bioremediation. The present study aimed to isolate crude oil-degrading marine bacteria from Vadinar coastal area of Gujarat, India. Among seven isolates, three potential bacterial strains were chosen for crude oil and petroleum hydrocarbon (PHC) degradation, which were analysed by UV spectrophotometric and fluorometric analysis. These bacterial cultures were verified by 16S rRNA gene sequencing and identified as Bacillus species. Phylogenetic analysis was carried out to confirm the evolutionary relationship with existing oil-degrading species. In the present study, drop collapse, oil spreading and emulsification assay were performed to detect biosurfactant production. Bacillus sp. NM1 KT354277 was capable of degrading 50% of PHCs at the end 72 h for one week under rotary incubation in ONR7a medium. Among the studied strains, Bacillus sp. NM3 KT354278 showed promising lipase activity, viz. 60.72 and 61.19 U ml -1 for 2% of olive oil and tributyrin respectively. Thus, the present study explores indigenous marine isolates that could be utilized as a potential alternative for oilspill remediation in future.

Newly Isolated Alkane Hydroxylase and Lipase Producing Geobacillus and Anoxybacillus Species Involved in Crude Oil Degradation

“…Research states that lipase is involved in inducing the lipolytic reactions of emulsified hydrocarbon at the lipid-water interface, thus assisting the hydrocarbon uptake [7]. Furthermore, many studies showed the presence of lipase intracellularly or extracellularly produced by hydrocarbon degraders from Bacillus and Pseudomonas species [7,9,16]. Nevertheless, in this study, lipase production does not affect the pH media (Figures 1b and 2).…”

“…The presence of complex compounds in crude oil such as alkanes, monocyclic, and polycyclic aromatic hydrocarbons causes toxicity to the environment and human health [2,4,5]. Crude oil biodegradation has been widely studied for the past few decades [6][7][8][9]. These studies have led to numerous microorganisms and their enzymes to be isolated and characterized.…”

Culture of Bacterium Bacillus subtilis as Degradation Agent in Attempt of Sea Water Remediation Contaminated By Petroleum

“…For example, research by Sorkhoh et al [15] reported that 368 genera of Bacillus isolated from oil-polluted Kuwaiti desert and two strains were capable of degrading 80-89% of crude oil (5 g/L) within 5 days at high temperature (60 °C). Recently, Mulani et al [12] have also reported that the genus Bacillus sp. which can grow efficiently on crude oil in coastal areas Vadinar, Gujarat, India, can degrade polyhydrocarbon cyclic (PHC) by 50% for 7 days.…”

“…Biosurfactants which are naturally generated by bacteria can reduce the surface tension of oil so that the crude oil will be more soluble. The more soluble crude oils can increase the accessibility of crude oils to the degrading bacteria and help them to consume hydrocarbon compounds in crude oils [12].…”

Indigenous Oil Degrading Bacteria: Isolation, Screening and Characterization

“…Due to immense utilization of petroleum based products, increased anthropogenic and industrial activities, there are irreversible and devastating effects on biodiversity as well as on human health [2]. Oil pollution is a form of pollution that leads to the release of poly aromatic hydrocarbons (PAHs) into the natural environment especially in water and soil disturbing ecosystem [3].…”