Profiling of Indigenous Biosurfactant-Producing Bacillus Isolates in the Bioremediation of Soil Contaminated by Petroleum Products and Olive Oil

Abstract

Petroleum is, up to this date, an inimitable nonrenewable energy resource. Petroleum leakage, which arises during transport, storage, and refining, is the most important contaminant in the environment, as it produces harm to the surrounding ecosystem. Bioremediation is an efficient method used to treat petroleum hydrocarbon-contaminated soil using indigenous microorganisms. The degradation characteristics for a variety of hydrocarbons (hexane, benzene, gasoline, and diesel) were qualitatively and quantitatively investigated using Bacillus isolates. Microbiological and biochemical methods have been used including isolation of oil-degrading bacteria, enzymatic activities, the determination of physicochemical parameters, biosurfactant production and extraction assay, oil displacement assay, antimicrobial assay of the biosurfactants, and bioremediation kinetics. Consequently, of the 60 isolates capable of degrading different hydrocarbons at fast rates, 34 were suspected to be Bacillus isolates capable of growing in 24 h or 48 h on BH medium supplemented with 2% of hexane, benzene, gasoline, diesel, and olive oil, respectively. Among the 34 isolates, 61% (21/34) are capable of producing biosurfactant-like molecules by using gasoline, 70% (24/34) with diesel oil, 85% (29/34) with hexane, and 82% (28/34) with benzene. It was found that biosurfactant-producing isolates are extractable with HCl (100%), ammonium sulphate (95%), chloroform (95%), and ethanol (100%). Biosurfactants showed stability at 20°C, 37°C, 40°C, and 60°C. Biosurfactant secreted by Bacillus strains has shown an antagonistic effect in Escherichia coli, Shigella flexneri 5a M90T, and Bacillus cereus. The selected isolates could therefore be safely used for biodegradation. Substrate biodegradation patterns by individual isolates were found to significantly differ. The study shows that benzene was degraded faster, followed by hexane, gasoline, and finally diesel. The Bacillus consortium used can decrease hydrocarbon content from 195 to 112 (g/kg) in 15 days.

Potential Utilization of Bacterial Consortium of Symbionts Marine Sponges in Removing Pollutants Global Trends: A Review

“…The reduction of the PAHs component (pyrene) by Bacillus bacteria (Fig. 1) increased with increasing interaction time, followed by an increase in the growth of bacillus cells [38,51]. The growth of Bacillus cells appeared to be stagnant on the 18th to 20th day of interaction (Fig.…”

“…Research on bioremediation of waste containing hydrocarbon components (aliphatic, aromatic) using several types of marine sponge symbiont bacteria shows the ability of these bacteria to degrade hydrocarbon components (Table 2) [12,100]. The search results above show that there are 3 (three) groups of symbiotic sponge bacteria (Bacillus, Pseudomonas and Acinetobacter) [38,52,127]. These bacteria showed biodegradation performance against hydrocarbon components [116].…”

“…This modification is believed to increase the degradability of PAHs because each type of bacteria can take on the role of degradation in parallel so that it can complete one cycle of conversion of pyrene to phenanthrene in a possibly shorter duration of time [71,90]. The study of the potential of the R-1 consortium bacteria was intended to remediate waste containing hydrocarbon components, especially PAHs, with high remediation performance and efficiency [38,145]. The degradability of bacteria was significantly increased, resulting in a high-efficiency degradation.…”

“…Bioremediation technology that uses the role of microorganisms as a decomposer component is generally good and is more often applied to wastewater treatment [34,35]. Sources of microorganisms that can carry out bioremediation functions can be obtained in an aquatic environment contaminated with pollutants, for example, in port areas, offshore oil processing industries or marine areas around locations that have experienced oil spills [36][37][38]. Pollutant degrading microorganisms can also be found in the soil, especially on land with a history of contamination due to oil spills and agricultural land exposed to pesticides [3,39].…”

Comparison of the Strength of Biodegradation of Pyrene between Symbiont Bacteria of Marine Sponges and Bacteria Isolated from Seawater

“…Bioremediation of PAHs using microorganisms has been widely developed. Several types of bacteria capable of carrying out the function of biodegradation of PAHs that have been isolated from seawater are suspected to be contaminated with hydrocarbons, including Bacillus [67], Gammaproteobacteria, Pseudomonadales [4,68]. Isolates from hydrocarbon contaminated soil, Micrococcus luteus [34], Lasiodiplodia theobromae [36], Pseudomonas aeruginosa [69].…”