Aspergillus brasiliensis-mediated biotransformation of methyl p-coumarate via phenyloxiran moiety: A predictive model for environmental bioremediation

Abstract

Among the various types of industry-generated effluents, those containing phenolic compounds are serious recalcitrant. There is therefore a need to develop new technologies that emphasize the depletion of these pollutants from the environment, and that work as a viable alternative to traditional physical and chemical remediation methods. Filamentous fungi are capable of producing a great number of enzymes that efficiently transform several organic compounds. Despite the use of fungi as first-choice agents for bioremediation of hazardous contaminants, the definitions of the chemical reactions and products that are included in the fungal transformation processes still are poorly reported. In this work, Aspergillus brasiliensis efficiently transformed methyl p-coumarate under an unexpected way into two new compounds, 5-(oxiran-2-yl)benzene-1,2,3-triol (23.03%) and 4-(3-hydroxyoxiran-2-yl)benzene-1,2-diol (4.90%), along with acetophenone (72.07%). The chemical structures of derivatives were determined by gas chromatography coupled to mass spectrometry (GC-MS) analysis and a plausible bioremediation pathway for phenolic recalcitrant was proposed. Interestingly, the uncommon phenyloxirane moiety has been formed as part of the transformation from 4-vinylphenol intermediate through double bond oxidation. Certainly, our results will open new insights in the bioremediation of phenolic compounds and they will be useful guidance for future planning of other similar processes.