Isolation and identification of crude oil degrading bacteria from gastropod Haustrum scobina collected from Persian Gulf (Bandar Abbas Shoreline provenance)

Biodegradation is a good alternative rather than chemical and physical methods for cleaning oil contaminated areas. Several factors like crude oil concentration, biosurfactant production, salinity and incubation time affect the biodegradation.
In this study, seawater sample and gastropod were collected from Persian Gulf. To isolate oil degrading bacteria from collected samples, ONR7a medium was used. The strains that had more growth and higher oil removal were selected and identified. The factors such as the effect of different concentrations of oil, incubation time, mixed cultures and salinity on the biodegradation were investigated.
Six crude oil degrading bacteria were isolated. Between these bacteria 2 strains were selected based on higher oil removal. These strains belonged to the genus Vibrio and Halomonas. Strains with higher Emulsification activity produce more biosurfactant and have higher oil biodegradation. Growth and oil degradation have increment pattern by prolonging the incubation time. Mixed culture of Vibrio and Halomonas strains have higher rates of degradation rather than culturing with one of them. Increase in crudeoil concentration to 2.5% caused reduction in growth of bacteria and degradation of oil.
Discussion and The results of this study show that crude oil degrading bacteria have high diversity in Persian Gulf. These bacteria have higher capability for oil degradation thus they can be used for remediation of oil contaminated areas.