Effect of biosurfactant and fertilizer on biodegradation of crude oil by marine isolates of Bacillus megaterium, Corynebacterium kutscheri and Pseudomonas aeruginosa

• Published in: Bioresource technology 2011, Vol.102 (2), p.772-778
• Main Authors: Thavasi, Rengathavasi, Jayalakshmi, Singaram, Banat, Ibrahim M.
• Format: Article
• Language: English
• Subjects: Bacillus megaterium; Bacillus megaterium - cytology; Bacillus megaterium - drug effects; Bacillus megaterium - growth & development; Bacillus megaterium - isolation & purification; Bacteria; Bacterial Adhesion - drug effects; Biodegradation; Biodegradation, Environmental - drug effects; Biological and medical sciences; Biological Assay; Bioremediation; Biosurfactants; Biotechnology; Corynebacterium - cytology; Corynebacterium - drug effects; Corynebacterium - growth & development; Corynebacterium - isolation & purification; Corynebacterium kutscheri; Crude oil; Degradation; Emulsions; Environment and pollution; Fertilizers; Fertilizing; Flasks; Fundamental and applied biological sciences. Psychology; Hydrocarbons - metabolism; Industrial applications and implications. Economical aspects; Laboratories; Marine; Petroleum - metabolism; Pseudomonas aeruginosa; Pseudomonas aeruginosa - cytology; Pseudomonas aeruginosa - drug effects; Pseudomonas aeruginosa - growth & development; Pseudomonas aeruginosa - isolation & purification; Reference Standards; Seawater - microbiology; Strain; Surface-Active Agents - pharmacology
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2010.08.099

This study was conducted to investigate the effects of fertilizers and biosurfactants on biodegradation of crude oil by three marine bacterial isolates; Bacillus megaterium, Corynebacterium kutscheri and Pseudomonas aeruginosa. Five sets of experiments were carried out in shake flask and microcosm conditions with crude oil as follows: Set 1–only bacterial cells added (no fertilizer and biosurfactant), Set 2–with additional fertilizer only, Set 3–with additional biosurfactant only, Set 4–with added biosurfactant + fertilizer, Set 5–with no bacterial cells added (control), all the above experimental sets were incubated for 168 h. The biosurfactant + fertilizer added Set 4, resulted in maximum crude oil degradation within shake flask and microcosm conditions. Among the three bacterial isolates, P. aeruginosa and biosurfactant produced by this strain resulted in maximum crude oil degradation compared to the other two bacterial strains investigated. Interestingly, when biosurfactant and bacterial cells were used (Set 3), significant oil biodegradation activity occurred and the difference between this treatment and that in Set 4 with added fertilizer + biosurfactant were only 4–5% higher degradation level in shake flask and 3.2–7% in microcosm experiments for all three bacterial strains used. It is concluded that, biosurfactants alone capable of promoting biodegradation to a large extent without added fertilizers, which will reduce the cost of bioremediation process and minimizes the dilution or wash away problems encountered when water soluble fertilizers used during bioremediation of aquatic environments.