Abstract

DIESEL DEGRADATION BY MICROBES AND ITS CONTROL

Karuppasamy Murugan* and M. A. Mohideen

ABSTRACT

In the present study reveals that, the effect of microbial contamination of diesel was examined through controlled experiments in a synthetic medium. For this, Bushnell-Haas broth was employed with diesel supplementation. Both in diesel supplemented and unsupplemented, bacterial cultures was inoculated and after 15 days, the population changes was examined in all the five test bacteria mainly Moraxella sp., Thiobacillus sp., Sulfobacillus sp., Gallionella sp. and Brucella sp. were found to utilize the hydrocarbon, diesel on the basis of an increase in their population. Simultaneously culture filtrate was subjected to FTIR and NMR analysis to understand the nature of diesel degradation in the Bushnell-Haas broth. In order to check the application of biocide such as CTAB, experiments conducted with CTAB at two different concentrations. Even though CTAB exhibited degradation on bacteria after 7 days, slow recovery of bacterial cells was recorded. NMR analysis indicates the effective degradation of diesel with the test bacterium. The probable mechanism of diesel degradation by these organisms could be oxidation as revealed by respective peaks in the NMR spectrum. On the basis of this analysis, it could be concluded that Gallionella sp. was the most efficient organism in diesel degradation followed by Moraxella sp., Thiobacillus sp. and Sulfobacillus sp. similar pattern was recorded in FTIR analysis also.

Keywords: Muck sample, Bushnell-Haas agar medium, Diesel degrading bacteria, Total viable count, Cetyl trimethyl ammonium bromide (CTAB), FTIR analysis and NMR analysis.