Effect of N-acetylcysteine against biofouling of reverse osmosis membrane

The influence of (1.5 mg/mL) of N-acetylcysteine (NAC). a non-antibiotic, mucolytic agent, on the biofouling of a reverse osmosis (RO) membrane by a multi-species culture (four environmental strains) of biofilm forming bacteria was studied. NAC was found to considerably suppress the formation of the biofilm on the RO membrane. The inhibitory effect of NAC on biofilm formation was verified by image based studies. There was over a 70% reduction in biofilm surface coverage when grown in the presence of NAC. Similarly, the average thickness and total biomass content of the biofilm formed in presence of NAC were significantly less than those of the control. These results suggest that NAC could be a potential agent for the control of biofouling of a RO membrane. However, the chemical stability, potential toxicity and consistent performance of NAC in the field will have to be further investigated for optimization of its use on a field scale. (C) 2011 Elsevier B.V. All rights reserved.