RESUMO
In this study, the consumption of 4-bromobenzoic acid and 4-chlorobenzoic acid by the fungus Penicillium brasilianum, an endophyte from Melia azedarach is evaluated. This fungus metabolizes these halobenzoic acids to produce three new brominated compounds, which have been isolated and characterized, and three new chlorinated derivatives identified by HRMS. Among these products, (4-bromobenzoyl)proline has been also chemically synthesized and employed in biological assays, thus providing insights for the elucidation of the defense mechanism of P. brasilianum towards these halobenzoic acids.
Assuntos
Antifúngicos/metabolismo , Bromobenzoatos/metabolismo , Clorobenzoatos/metabolismo , Endófitos/metabolismo , Melia azedarach/microbiologia , Penicillium/metabolismo , Antifúngicos/química , Biotransformação , Bromobenzoatos/química , Clorobenzoatos/química , Endófitos/química , Halogenação , Melia azedarach/metabolismo , Simulação de Acoplamento Molecular , Penicillium/química , Penicillium/enzimologiaRESUMO
UHPLC-DAD-HRMS based dereplication guided the detection of new halogenated alkaloids co-produced by Talaromyces wortmannii. From the fungal growth in large scale, the epimers 2,8-dichlororugulovasines A and B were purified and further identified by means of a HPLC-SPE/NMR hyphenated system. Brominated rugulovasines were also detected when the microbial incubation medium was supplemented with bromine sources. Studies from 1D/2D NMR and HRMS spectroscopy data allowed the structural elucidation of the dichlorinated compounds, while tandem MS/HRMS data analysis supported the rationalization of brominated congeners. Preliminary genetic studies revealed evidence that FADH2 dependent halogenase can be involved in the biosynthesis of the produced halocompounds.
Assuntos
Indóis/isolamento & purificação , Talaromyces/química , Talaromyces/crescimento & desenvolvimento , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Alcaloides de Claviceps/biossíntese , Flavina-Adenina Dinucleotídeo/análogos & derivados , Flavina-Adenina Dinucleotídeo/metabolismo , Proteínas Fúngicas/metabolismo , Halogenação , Indóis/química , Estrutura Molecular , Talaromyces/enzimologiaRESUMO
In our continuous studies on the chemistry of the endophytic fungus Penicillium griseoroseum, an endophyte isolated from fruits of Coffea arabica, we isolated clavatol, a dimethylated tetraketide, and its dimer which appears to be a novel natural compound. The studies also resulted in the identification of two known tetronic acids, viridicatic acid and terrestric acid, found in ethyl acetate and n-butanol extracts. Spectroscopic studies using 1-D and 2-D NMR and MS/MS analysis were performed to determine the structures of these compounds, first reported by this Penicillium. Two other tetronic acids congeners were identified through HPLC/MS/MS studies, based on fragmentation pattern of ions produced from ionised tetronic acids, and UV light absorptions.
Assuntos
Furanos/química , Penicillium/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas em TandemRESUMO
The oxidative potential of the fungus Penicillium brasilianum, a strain isolated as an endophyte from a Meliaceae plant (Melia azedarach), was investigated using 1-indanone as a substrate to track the production of monooxygenases. The fungus produced the dihydrocoumarin from 1-indanone with the classical Baeyer-Villiger reaction regiochemistry, and (-)-(R)-3-hydroxy-1-indanone with 78% ee. Minor compounds resulting from lipase and SAM activities were also detected. The biotransformation procedures were also applied to a collection of Penicillium and Aspergillus fungi obtained from M. azedarach and Murraya paniculata. The results showed that Baeyer-Villiger were mostly active in fungi isolated from M. azedarach. Almost all of the fungi tested produced 3-hydroxy-1-indanone..
