Research on antifungal and inhibitory eff ects of DL-limonene on some yeasts

Th is study was undertaken to investigate the antifungal eff ect of DL-limonene on yeasts using disk diff usion and the minimum inhibitory concentration (MIC). Th e eff ect of DL-limonene on ethyl alcohol fermentation by Saccharomyces cerevisiae was also investigated. According to disk diff usion results, the development of an inhibition zone was observed in all microorganisms tested. Th e inhibition zones were larger than those occurring with the Fungizone antibiotic used as the control. Inhibition zone diameters increased with increasing amounts of DL-limonene. MIC results varied between 500 and 4000 μg mL−1 depending on the yeast strain. DL-limonene at a concentration of 0.20% (w v−1) inhibited cell growth, ethanol formation, and sugar utilization by S. cerevisiae.