Effect of addition of nitrogen, phosphorus and potassium fertilizers on biodegradation of crude oil by marine bacteria

摘要

Role of marine bacteria viz. Marinococcus albus, Methylobacterium mesophilicum and Nocardia otitidiscaviarum in bioremediation of crude oil contaminated Alang sea coast has been evaluated in the present study. Optimum concentrations of inorganic nutrients N, P & K as urea, super phos and potash fertilizers respectively on growth and degradation has been determined. Addition of optimum concentrations of N (1%), P (0.5%) and K (0.01%) in combination significantly enhanced biodegradation by 22 to 32%. Bioremediation studies indicated that a Bacterial consortium (BC) exhibited maximum growth and degradation on addition of optimum concentrations of N, P and K. Maximum effect in increase in growth was on a BC (0.54 mg/ml) whereas, maximum effect on increase in degradation was on N. otitidiscaviarum (31.9%). However, complete degradation was not possible due to the presence of recalcitrant molecules and accumulation of toxic metabolites during biodegradation. Three isolates can successfully be used to formulate a successful bioremediation strategy for oil contaminated marine environment.