Microbial degradation of acetaminophen, a pharmaceutical compound, using the ascomycete fungus Trichoderma asperellum

The tropical fungus Trichoderma asperellum was identified as a novel acetaminophen degrader, achieving 88.8% removal of 1 g/L acetaminophen in liquid culture under optimal conditions (pH 4.7, 0.55% w/v salinity, 9.7 g/L glucose, and 4.5 g/L peptone). A unique enzyme pattern, predominantly dioxygenase (146 U/mL on day 7), exhibited a degradation mechanism distinct from the ligninolytic enzyme system traditionally associated with fungal biodegradation. The GC-MS analysis has identified some intermediates, including p-aminophenol, 1,3-dihydroxybenzene, phenol, and butenoic acid. At the same time, some of the metabolites have not been reported previously in fungal degradation of acetaminophen. The distinct pattern of enzyme response and the identification of novel intermediates indicate that T. asperellum follows a distinct oxidative hydrolytic route, highlighting its potential as a new fungal candidate for the bioremediation of pharmaceuticals. In optimised conditions, 88.8% acetaminophen can be degraded by Trichoderma asperellum. The predominant degradative enzyme identified in enzyme profiling was dioxygenase. GC-MS detected new intermediates to indicate a different metabolic pathway for the degradation of acetaminophen.