ABSTRACT
Many bacteria detect their critical cell numbers through a mechanism known as quorum sensing (QS). Acyl homoserine lactones (AHLs) mediated QS systems have been shown to operate in important human pathogens. The aim of this study was to evaluate the inhibitory effect generated by zoosporic freshwater fungi on AHLs production. A potent strain of zoosporic fungi, Leptolegniella keratinophilum, was isolated after extended screening study. A new cheap medium was used to support the anti-AHLs activities. Statistical strategy depending on two levels factorial model and three levels quadratic model were applied to guide a production maximization process. The three levels Box-Behnken model possessed the ability to optimize the significant nutritional and cultural conditions and to predict the maximum that can be achieved. In the course of study, we reached 88% anti-AHLs activity, while the initial activity was 63%. There was no previous maximization methodology for either the experimental medium, or the fungi. The results suggest that freshwater zoosporic fungi can be potentially used against bacterial infections.
