Utilization of detergent surfactant by bacteria isolated from freshwater bodies

Abstract

The utilization of detergent surfactants by bacterial species isolated from some freshwater bodies was
studied using primary degradation under OECD screen test. the persistence of the detergent surfactant in the water
bodies was also investigated using River water die-away test. Nineteen bacterial species were isolated in all. Three of
the isolates designated as surfactant utilizing bacteria (SUB): Citrobacter sp., Micrococcus luteus and Pseudomonas sp.
were found to utilize the detergent surfactants as a source of carbon. The highest rate of individual utilization (43%)
was observed with Pseudomonas, while a consortium of the three SUB isolates achieved 62% reduction in 21 days.
None of the isolates demonstrated co-metabolic activity. The surfactant persisted for 12 to 15 days at 50 – 50.35%
concentration in the water bodies. The persistence of the surfactants is discussed and the use of the SUB species in
bioremediation of the detergent effluent is suggested as a way of ameliorating the observed persistence of the surfactant
in the water bodies.