Degradation of lineal alkylbenzene sulphonate (LAS) in an acidogenic reactor bioaugmented with a Pseudomonas aeruginosa (M113) strain

The degradation of of lineal alkylbenzene sulphonate (LAS) was studied in a two-stage anaerobic system where the acidogenic reactor was bioaugmented with a strain of Pseudomonas aeruginosa (M 113). This is a strain, which under aerobic and denitrifying conditions uses LAS as carbon source. Results show that LAS was only degraded within the acidogenic stage while in the methanogenic reactor there was no degradation and eventually there was an inhibition due to a LAS accumulation in the sludge. During the experiment, the M 113 strain remained in the acidogenic conglomerate (at around 10(4) CFU/mL) although there is no evidence of their involvement in LAS degradation.