In vitro anti-yeast activity of chloramphenicol: A preliminary report

Chloramphenicol is a bacteriostatic antimicrobial agent but its antifungal activity is not known. The present study aimed to investigate the activity of chloramphenicol against 30 representative yeasts. The antimicrobial assay of chloramphenicol (50mg/mL; 100mg/mL and 200mg/mL) was determined by the disc diffusion method using Mueller-Hinton agar against 30 representative yeast strains. Zone of inhibition was read after 48-72h incubation at 37°C and results were compared with some standard antifungal agents. Most of the tested yeasts (73.3%) showed inhibition zones (5 up to 35mm) to chloramphenicol impregnated discs (200mg/mL). Three out of the four tested Candida albicans as well as Candida famata, Candida glabrata, Candida haemolonei and Cryptococcus neoformans showed no inhibition zones to chloramphenicol (200mg/mL). Caspofungin acetate (50mg/mL) inhibited 83.3% of the strains; ketoconazole (200mg/mL) 70% and metronidazole 10%. Chloramphenicol discs: 50 and 100mg/mL showed less activity (6.7% and 36.7%, respectively) compared to the 200mg discs; whereas chloramphenicol (BBL; 3μg/mL) inhibited 13.3% of the strains. The anti-yeast activities of chloramphenicol were comparable to other known antifungal compounds. Moreover, it is cheap, has fewer side effects and its inclusions in selective fungal media such as Mycosel have to be questioned.