Resumen:
oumarin metabolism by several Aspergillus strains was studied. Aspergillus ochraceus andAspergillus niger carried out the reduction of the C3-C4 double bond to yield dihydrocoumarinin 24 h. Meanwhile, the first strain did not transform dihydrocoumarin after 7 d,A. niger demonstrated to have two divergent catabolic pathways: (a) the lactonemoiety opening and further reduction of the carboxylic acid furnishing the primary alcohol2-(3-hydroxypropyl)phenol and, (b) the hydroxylation of the aromatic ring of dihydrocoumarinat a specific position to give 6-hydroxy-3,4-dihydrochromen-2-one. Aspergillus flavusdid not perform double bond reductions, and only produced oxygenated metabolites,mainly 5-hydroxycoumarin. Enzyme-specific inhibitors and a coumarin analogous wereuseful to confirm the A. niger catabolic route.