Mimiking the anti biofilm activity of peracetic acid and hydrogen peroxide in industrial water systems

Abstract

Statement of the Problem: One of the challenging issues in the pharmaceutical industry is facing with the biofilms in water systems. Biofilms are an organized community of microorganisms that bind to and grow onto biotic or non-biotic surfaces. If a biofilm develops then an out-of-control situation is likely to emerge. In this study, the effects of two disinfectants of peracetic acid at contact times and temperatures combinations on biofilm. Method: in vitro production of biofilms was performed by highly reproducible 96 well microtiter-based method using E. coli bacterial strain isolated from deionizer of a pharmaceutical plant water system at 37°C up to 96 hours. The anti-biofilm activity of peracetic acid was investigated at concentrations of 0.15-0.5% for contact time of 5-15 minutes at 20°C to 60°C. Results: Optimum biofilm formation was observed at 37 °C, 96 hours incubation and interestingly in the absence of albumin equal to 1,792 OD of biomass. Also, the best biofilm growth at 37 °C in presence of albumin was produced after 96 hours incubation (1.377 OD). The anti-biofilm effect of peracetic acid was observed at concentrations of 0.25% and up at 40-60 ° C and at 10-15 min; and the optimum condition was selected as 40°C/10min of 0.25% to be applied in the factory’s water system in buffer tank section. Conclusion: According to the results obtained in this study, the best concentration of peracetic acid for anti-biofilm activity using factory’s common bacterial strain was practically shown to be at concentrations above 0.25%, temperature of 40° C and a minimum of 10 minutes of incubation. In-house validation and periodical changing of the sanitization policy is of great importance in biofilm control of water systems in pharmaceutical plants.