Effect of nutrients on the microbial degradation of hydrocarbon by a marine microorganism, Pseudomonas sp

In order to improve the microbial degradation rate of n-tetradecane by Pseudomonas sp. in enriched sea water, the growth mediums which consisted of various nutrients as nitrogen and phosphorus source were investigated experimentally. It was shown that the seawater medium enriched by NH4NO3, K3PO4 and yeast extract was most appropriate to degrade n-tetradecane by Pseudomonas sp. When NH4NO3/K3PO4 ratio was maintained at 10, the relation between the biodegradation rate of oil, rm mg-oil l-1h-1, and the nutrient concentration, S mg-NH4NO3l-1, was in good agreement with the following equation. rm=max·S/Km+S where (rm) max was the maximum rm and Km was the saturate constant. For the initial concentration of oil, 153 mg l-1, (rm) max was determined to be 4.9 mg-oil l-1h-1 and Km was 94 mg-NH4NO3 l-1. Furthermore rapid degradation of the oil was suggested to be a result of the enhanced growth rate of Pseudomonas sp., hence the increased production of emulsifier in the improved medium.