Biodegradation of metronidazole by isolated penicillium spp

ABSTRACT

An accidental contamination of metronidazole [MDZ] infusions was detected. The contaminant was identified as Penicillium spp.. The fungus grew rapidly on Czapek- Dox solution containing MDZ [0.5%] as a sole carbon and energy sources. HPLC analysis of the biodegradation products of MDZ by the isolated Penicillium spp. suggested that biodegradation pathway of MDZ involved at least two intermediates; the less active hydroxy and the inactive acelyl derivatives of MDZ. The two intermediates were also detected as inactivation products in the urine of humans after oral administration of MDZ. These results indicate that detoxification mechanism of MDZ in eukaryotics might be similar. Biodegradation of MDZ by Penicillium spp. was affected by temperature, pH and the length of incubation period. Maximum biodegradation was observed after 7 days incubation at a temperature of 25°C and pH 5.5. The biodegradation system of MDZ is inducible and seems to be located in the peirplasmic space of the fungus