EFFECT OF CRUDE OIL CONCENTRATIONS, TEMPERATURE AND PH ON GROWTH AND DEGRADATION OF CRUDE OIL BY MARINE BACTERIA

Abstract

sequence of events. Among these, isolate TV 11 showed maximum growth (0.70 mg/ml) and degradation (22.8 %) on 34 th day, followed by TV 4 that showed maximum growth (0.60 mg/ml) and degradation (17.0 %) and TV 3 that showed maximum growth (0.59 mg/ml) and degradation (16.2 %) on 28 th day of incubation. Isolate TV 11 was identified as Marinococcus albus, TV 3 as Methylobacterium mesophilicum and TV 4 as Nocardia otitidiscaviarum. Effect of various crude oil concentrations (2 - 6 g/l), temperature (20 – 37 oC) and pH (6 - 9) on growth and degradation revealed that 5 g/l of crude oil concentration, 30 oC temperature for M. albus and 25 oC for M. mesophilicum and N. otitidiscaviarum and pH 7 were optimum for both growth and degradation. Enhanced bacterial growth and degradation achieved with optimized concentrations of crude oil, temperature and pH can make their use suitable in devising an appropriate bioremediation strategy for oil contaminated sites.