Diversity of oil-degrading bacteria isolated form the Indian Ocean sea surface

Abstract:

Abstract: [Objective] In order to investigate the diversity of oil-degrading bacteria in the surface seawater across the India Ocean, and to obtain new oil-degrading bacteria. [Methods] Potential oil-degrading bacteria were selected out via 1:1 mixture of diesel and crude oil as sole carbon source. Meanwhile, the community structure of 13 enrichments was analyzed by polymerase chain reaction with denaturing gradient gel electrophoresis (PCR-DGGE). [Results] We obtained 51 unique strains of 29 genera after screening via morphological, physiological, biochemical and 16S rRNA analyses. They mainly belonged to α and γ- Proteobacteria. The four genera Alcanivorax (accounting for 18%), Novosphingobium (10%), Marinobacter (6%) and Thalassospira (6%) were the most predominant bacteria. Ecological analyses showed that the bacteria had high diversity with Shannon-Winner index (H) of 4.57968, and distributed even with Evenness index (E) as 0.8664771. Then Further experiments revealed oil-degrading capability of 49 strains. In addition, our investigation revealed oil-degrading ability of genera Sinomonas, Knoellia and Mesoflavibacter for the first time. DGGE fingerprint patterns indicated that the genus Alcanivorax was an important oil-degrading bacteria in the surface seawater across the India Ocean. [Conclusion] This study demonstrated a high diversity of the oil-degradation bacteria in the surface seawater of Indian Ocean, these bacteria are of potential in bioremediation of marine oil pollution.