Screening for the involvement of the hydroxyl radical in the biodegradation of glyceryl trinitrate by Penicillium corylophilum Dierckz

In this investigation the ability of free hydroxyl radicals generated via the reaction between an iron salt and H2O2 to degrade glyceryl trinitrate (GTN) was investigated. In a period of 27 h, GTN was completely degraded by free hydroxyl radicals when tested at 50 mg l−1 concentration. Degradation could not be accomplished by H2O2 or the iron salt alone. A free hydroxyl radical scavenger, bulbocapnine, completely inhibited the degradation of GTN supporting the conclusion that the hydroxyl free radicals may be responsible for the degradation of GTN. Our previous investigation revealed that a fungal culture, Penicillium corylophilum Dierckz, has the capability to completely degrade GTN within 308 h (Zhang, Y., Sundaram, S. T., Sharma, A. and Brodman, B. W. Applied and Environmental Microbiology 63(5): 1712–1714 (1997)1). In the present investigation, we studied the possibility of the involvement of free hydroxyl radicals in the biodegradation of GTN. This study was carried out with the inclusion of bulbocapnine in the fungal growth medium indicating that the free hydroxyl radicals were not involved in the degradation of GTN by P. corylophilum.