The influence of ketoconazole on the activity of asparagine protease produced by Candida strains.

The investigations concerning the activity of antimycotic drugs on pathogenic fungi, revealed a decrease of sensitivity of fungi, especially of the Candida species. In other investigations we have stated that strains isolated from patients have other than standard enzymatic activity. So it seems to be interesting to have evaluated the model for analysis in vitro the influence of antimycotic drug for egzoenzyme of fungi. The aims of the study were: 1. estimation of the influence in vitro ketoconazole, which was added everyday for 3 weeks on curves of activity of the drug, on strains isolated from patients; 2. estimation of asparagine protease activity on strains before, during and after the added drug to the culture. During the study we evaluated the model in vitro to obtain strains with lower sensitivity for a antimycotic drug. Everyday during a 3 week period we added to the culture ketoconazole in the concentration of about 2, 4 and 6 times higher than the minimal inhibitory concentration (MIC). Before, 1, 2 and 3 weeks after we investigated the activity of asparaginee protease. We obtained the following results: 1. Ketoconazole added to the culture of Candida strains during 3 weeks had influenced the response curves, which was observed as statistical significant changes between MIC values. 2. Ketoconazole after 1 week of administration decreased and after 2 and 3 weeks increased of asparagine protease activity.