Synergistic ex-situ biodegradation of crude oil by halotolerant bacterial consortium of indigenous strains isolated from on shore sites of Gujarat, India

Hydrocarbon pollution due to activities of petroleum industry is a major problem worldwide especially in developing countries like India. Hydrocarbon utilizing bacterial consortium (HUBC) consisting of six (06) bacterial isolates viz. Ochrobactrum sp. (01), Stenotrophomonas maltophilia (02) and P. aeruginosa (03) isolated from crude oil polluted sites of ONGC fields of Gujarat, India. The isolates were identified by using VITEK (R) 2 Compact and 16S rDNA gene sequencing. Scale up study of crude oil degradation (K#X, 3% v/v) by HUBC using Bushnell-Hass medium was performed under optimized growth conditions up to 75 days. Gravimetric and gas chromatographic analysis showed 83.70% and 83.49% (C8-C35) degradation, respectively. Presence of paraffins (C20-C40) in crude oil causes well clogging problem during exploration activities. The HUBC utilized paraffin content of crude oil and hence can be used to solve this problem. The findings of ex-situ bioaugmentation studies by halotolerant HUBC suggests its utility for effective in situ bioremediation of hydrocarbon contaminated sites as well as management of sea surface oil spills. (C) 2015 Elsevier Ltd. All rights reserved.