Propan-2-ol

Propan-2-ol has sufficient bactericidal activity at 70% in 15 s, yeasticidal activity at 50% in 5 min, incomplete fungicidal activity at 70% in 10 min and tuberculocidal activity at 60% in 5 min. The antimicrobial effect of propan-2-ol is explained by the non-specific denaturation of proteins and deformation of membranes. No specific cellular defence mechanisms against propan-2-ol have been described. Propan-2-ol between 40% and 95% can significantly increase biofilm formation in S. aureus and S. epidermidis. The effect of propan-2-ol on biofilm fixation is unknown. Biofilm removal by 70% propan-2-ol is very low at 0% for P. aeruginosa and S. aureus. E. faecium isolates with a relative tolerance to 23% propan-2-ol have been described. Exposure to 1–6% propan-2-ol can increase biofilm formation in S. aureus, and 2.5% propan-2-ol can increase surface attachment in L. monocytogenes. Biofilm development of C. albicans can be inhibited by 2% propan-2-ol. Susceptibility to propan-2-ol can be significantly reduced by exposing E. coli to sublethal concentrations. No propan-2-ol-resistant isolates have been described with an insufficient efficacy in suspension tests or tests under practical conditions compared to culture collection strains or with a contamination of disinfectants. The overall probability of resistance to propan-2-ol of practical relevance is very low in the absence of biofilm.