Alkane biodegradation by a microbial community from contaminated sediments in Patagonia, Argentina

Biodegradation of a mix of normal alkanes (decane, dodecane, tetradecane, hexadecane, octadecane and eicosane) was studied in batch cultures after inoculating with microbial communities from pristine and hydrocarbon contaminated sediments. Analysis showed that the community from polluted sediments reduced the concentrations of all alkanes to < 5 mg l−1 after a 240-h incubation period (< 5% initial concentration), while the control community only degraded 5–10% of them. The hydrocarbon adapted community showed a lag phase of 48 h, in which no alkane biodegradation was found, followed by a 96-h growth period and a stationary phase from that moment, whereas the control community grew poorly. Isolated strains were mainly Gram-negative, motile and non-glucose fermenter rods. Based on these results, it could be concluded that the hydrocarbon adaptation of microorganisms led to an increase in alkane biodegradation. This capacity could be useful to improve biodegradation of hydrocarbon regional wastes.