Abstrait

Comparative Studies on Bacterial Consortia for Hydrocarbon Degradation

Sunita J. Varjani and Vivek N. Upasani

Globally environmental scientists have shown increased interest in promoting biological methods referred to as “Green technology” in the clean-up technologies for hydrocarbon-polluted sites. These methods are less expensive and do not introduce additional chemicals/pollutants into the environment. Compared to physico-chemical methods, bioremediation / biodegradation offer a feasible alternative for this purpose to the petroleum industry. One reason is that the majority of the molecules in the crude oil and refined products are biodegradable. We have reported the isolation of Hydrocarbon Utilizing Bacteria (HUB) from crude oil contaminated soil and Untreated Effluent water (UEW) samples collected samples from selected ONGC sites in Gujarat state. Screening for hydrocarbon utilizing capacity of these bacteria was carried out using Bushnell-Hass (BH) medium with crude oil (K#X) and redox indicator 2, 6 - dichlorophenol indophenol (DCPIP). Maximum utilization of hydrocarbons from crude oil was indicated by the total discoloration of DCPIP. In total five consortia (Hydrocarbon Utilizing Bacterial Consortium: HUBC) named HUBC-S, HUBC-W, HUBC, HUBC-Ank, and HUBC-AH were prepared to screen for the most efficient consortium for hydrocarbon degradation. Our results indicated that the consortium HUBC consisting of six isolates showed best results. Total discolouration of DCPIP by “HUBC” and its individual isolate was about 53 h and 120 h, respectively. The results of this study are presented here.