Gabe Berken

Candida albicans is a commensal gastrointestinal yeast in humans that has pathogenic potential and is potentially deadly in immunocompromised individuals. Past work from our lab has shown that yeast, including C. albicans, isolated from fecal samples from non-human mammals exhibit tolerance to stressors consistent with what is found in a mammalian body indicating potential commensalism. Since these non-human mammals might harbor potential pathogens the question of whether these strains have innate drug resistance, and thus pose a potential health concern for humans was addressed. 35 yeasts, 5 of which were determined to be C. albicans by ITS1 region sequencing, were exposed via a disk diffusion assay to Micafungin (5µg), Amphotericin B (10µg), and Fluconazole (15µg). The group of the other 30 yeasts were comprised of two controls, one being a human blood isolate of C. albicans and the other being a fluconazole resistant strain of C. albicans, and preliminarily identified yeasts from both fecal and soil samples. Resistance levels were determined by the size of the zone of inhibited growth. Ultimately, environmental C. albicans, relative to our control and one another, along with several other environmental yeasts showed tolerance or resistance to Fluconazole, though none showed tolerance or resistance to either Amphotericin B or Micafungin.