A Biological Approach to Marine Oil Spill Remediation using Bacillus cereus

Abstract

Oil pollution in marine environments is a major global environmental concern, largely driven by increasing oil demand and intensive maritime activities. This study aimed to evaluate the potential of Bacillus cereus for the biodegradation of crude oil and engine oil in seawater as an environmentally friendly approach to oil spill remediation. A laboratory-based biodegradation experiment was conducted using Bacillus cereus isolated from the Ranau Hot Spring, Sabah. Biodegradation assays were performed in eight experimental sets containing 10% and 15% (v/v) concentrations of crude oil and engine oil, with an incubation period of 30 days. Biodegradation efficiency and rate were determined by comparing the initial and final concentrations of crude oil and engine oil, while the degradation of aliphatic hydrocarbons was assessed by comparing chromatographic peak areas before and after treatment using Gas Chromatography–Mass Spectrometry (GC–MS). The results demonstrated that Bacillus cereus achieved the highest biodegradation efficiency in 10% (v/v) engine oil, which was 1.76-fold higher than crude oil and 2.98-fold higher than for 15% (v/v) crude oil. Similarly, the highest biodegradation rate was recorded for 10% (v/v) engine oil, being 2.17-fold higher than that for 10% (v/v) crude oil and 3.77-fold higher than for 15% (v/v) crude oil. GC–MS analysis revealed that aliphatic hydrocarbon compounds in engine oil were more extensively degraded than those in crude oil. Overall, this study highlights the strong potential of Bacillus cereus as an effective bioremediation agent, particularly for engine oil contamination in marine environments.