Estimating Maximum Growth Rates of Petroleum Metabolizers from Turbidity Data Using Exponential Growth Method

摘要

Micro-organisms which are believed to metabolize waste petroleum oils from soaked soils were isolated and characterized into appropriate genera in an earlier publication. Further studies conducted on the isolates showed that isolates from petrol contaminated soils were more efficient metabolizers. The maximum growth period which occurred at the end of the logarithm phase was 5 days for petrol isolates and 6 days for Kerosene, Diesel and Engine oil isolates. This paper has shown that the maximum growth rates of the isolates determined by the exponential growth model showed that the isolates from Engine oil contaminated soils gave the highest growth rate followed by Diesel, Petrol and Kerosene respectively. The time required for doubling cell mass concentration in ascending order was Diesel, Petrol, Engine oil and Kerosene. The average pH and temperature for maximum growth of the isolates were determined to be 7.3 and 304K respectively. The work has also shown that the isolates are similar in nature and they show mesophilic characteristics.