Biodegradation of hydrocarbons using microbial consortium
Soma Prabha A, Jayachitra A
The biodegradation of PAHs can be considered on one hand to be part of the normal processes of the carbon cycle, and on the other as the removal of man-made pollutants from the environment. In recent decades the major source of PAH pollution is industrial production, transportation, refuse burning, gasification and plastic waste incineration. Polycyclic aromatic hydrocarbons (also known as polynuclear aromatic hydrocarbons) are composed of two or more aromatic (benzene) rings which are fused together when a pair of carbon atoms is shared between them. The environmentally significant PAHs are those molecules which contain two (e.g., naphthalene) to seven benzene rings. In the present investigation, the oil contaminated soil sample was collected from oil contaminated site, in Madurai. The oil degrading microorganisms (Pseudomonas sp, Bacillus sp, Micrococcus sp) were isolated from oil contaminated soil by using enrichment technique. The colonies with different morphological colonies were selected and further characterized by using standard characterization method. The organisms were identified as Pseudomonas sp, Bacillus sp and Micrococcus sp. The degradation of aromatic hydrocarbon (petrol and crude oil) was performed with 1% diesel and petrol in MSM medium. The results revealed that an enhanced degradation was observed in Pseudomonas fluorescens. The effect of pH, temperature, carbon and nitrogen sources for hydrocarbon degradation was performed for Micrococcus, Pseudomonas and Bacillus sp with petrol and crude oil as substrate. The emulsification stability of crude oil and petrol for the hydrocarbon degrading microorganisms were also performed. In this present investigation, the chemo taxis properties of the three microorganisms were performed.