ABSTRACT
The phenoloxidase (POx) activities of 1059 strains and species of micromycetes were determined on malt/agar medium. Overall, 600 (57%) of the isolates produced one or more POx. The sensitivity and specificity of the POx activities towards various substrates were used to group the isolates. Some 187 strains (31% of those producing POx) produced well-defined enzymes, 236 (39%) produced incompletely identified enzymes and 177 (30%) produced other, unidentified POx.
ABSTRACT
The ability of 814 strains of Micromycetes to grow on ferulic and syringic acids was investigated. After cultivation on solid media, 106 and 108 strains were selected and cultivated in liquid synthetic medium. Chromatographic analysis allowed classification of fungi into different groups according to the consumption of phenolic compounds and the appearance of new metabolites. Finally, Paecilomyces variotii and Pestalotia palmarum were chosen and cultivated in the presence of ferulic acid in two different culture media. These two Fungi Imperfecti were able to consume the phenolic compound rapidly and completely.
Subject(s)
Anticoagulants/metabolism , Coumaric Acids/metabolism , Fungi/metabolism , Gallic Acid/analogs & derivatives , Chromatography, High Pressure Liquid , Chromatography, Thin Layer , Culture Media , Gallic Acid/metabolism , Indicators and ReagentsABSTRACT
Ferulic acid metabolism was studied in cultures of two micromycetes producing different amounts of phenol oxidases. In cultures of the low phenol oxidase producer Paecilomyces variotii, ferulic acid was decarboxylated to 4-vinylguaiacol, which was converted to vanillin and then either oxidized to vanillic acid or reduced to vanillyl alcohol. Vanillic acid underwent simultaneously an oxidative decarboxylation to methoxyhydroquinone and a nonoxidative decarboxylation to guaiacol. Methoxyhydroquinone and guaiacol were demethylated to yield hydroxyquinol and catechol, respectively. Catechol was hydroxylated to pyrogallol. Degradation of ferulic acid by Paecilomyces variotii proceeded mainly via methoxyhydroquinone. The high phenol oxidase producer Pestalotia palmarum catabolized ferulic acid via 4-vinylguaiacol, vanillin, vanillyl alcohol, vanillic acid, and methoxyhydroquinone. However, the main reactions observed with this fungus involved polymerization reactions.
