INFLUENCE OF THE POSTANTIBIOTIC EFFECT AND POSTANTIBIOTIC SUB-MICS EFFECT OF NETILMICIN, TOBRAMYCIN, CIPROFLOXACIN AND PEFLOXACIN ON ALGINATE PRODUCTION BY PSEUDOMONAS-AERUGINOSA

The postantibiotic effect (PAE) (postantibiotic phase induced by 2x or 4x MIG) as well as the postantibiotic effect of subinhibitory concent rations (0.1x, 0.2x and 0.3x MIG) (PA SME) of netilmicin, tobramycin, ciprofloxacin and pefloxacin affected the production of the virulence factor alginate by a P. aeruginosa strain. Aminoglycosides and ciprofl oxacin at a concentration of 4x MIC inhibited the alginate production more significantly than 2x MIG. Suprainhibitory concentrations of amin oglycosides were more effective than pefloxacin (2x or 4x MIG) and cip rofloxacin (2x MIG). PA SME demonstrated by the above antibiotics (wit h the exception of ciprofloxacin 2x MIC + 0.1x MIG) suppressed alginat e production more efficiently.