Bioremediation of Coastal and Marine Pollution due to Crude Oil Using a Microorganism Bacillus subtilis

Abstract

Marine and coastal pollution has become a global concern in recent years due to the increase in intensity of contaminants in the marine environment. The release of crude oil in the marine environment during exploitation and transportation cause serious environmental pollution, owing to the presence of toxic organic compounds. Crude oil, which is the most predominant energy resource throughout the word is the complex mixtures of hydrocarbons including more than 70% of alkanes along with aromatics, naphthenes, and resins. The long chain alkanes present in the crude oil remains persistent due to its non-volatile nature and pose a major menace to terrestrial and marine ecosystems. Biodegradation has emerged as a potential and economical technology for the restoration of oil spilled environment. It provides efficient, economical and environment friendly solution for on-shore and off-shore oil spill remedies. The present study investigates the degradation of crude oil using a biosurfactant producing microorganism ‘Bacillus subtilis’ to obtain maximum degradation. Bacillus subtilis isolated from polymer dump site, Chennai, India was used for the degradation of crude oil. Crude oil degradation and viscosity reduction was observed to be 80% and 60%, respectively, in 10 days. The high microbial adherence, surface tension reduction, emulsification activity, production of higher amount of biosurfactant, stability of the produced biosurfactant at extreme environment conditions, viscosity reduction and high rate of degradation indicates the potential of the microorganism for oil spill treatment.