Isolation and Characterization of Long-chain n-Alkane-Degrading Bacillus coagulans from Contaminated Soil

Abstract A strain capable of oxidizing alkanes up to C36 was isolated from petroleum-contaminated soils. The strain was able to utilize paraffinic wax and liquid paraffin as the sole carbon sources for growth, and the growth with paraffinic wax was accompanied by the production of an unknown emulsifying agent. The ranges of pH value and temperature for satisfactory growth of strain W cells were from 4.0 to 8.0 and 10°C to 45°C, respectively. The kinetics of n-eicosane, n-triacontane, and n-hexatriacontane biodegradation was investigated with initial concentrations of 1,000 mg L−1. First-order kinetics could be fitted to the biodegradation of solid hydrocarbons by strain W at initial concentrations of 1,000 mg L−1. The first-order oxidation constant decreased with increasing chain length. When C36 was used as the sole carbon source, a wide variety of metabolites including fatty acids were formed and identified. Results could offer useful information for the application of strain W in bioremediation of petr...