Evidence of a new biotransformation pathway of p-coumaric acid into p-hydroxybenzaldehyde in Pycnoporus cinnabarinus.
Pycnoporus cinnabarinus MUCL39533 was shown to be able to convert p-coumaric acid into p-hydroxybenzaldehyde, a component of high organoleptic note present in natural vanilla aroma. Use of phospholipid-enriched medium led to high-density cultures of P. cinnabarinus, since dry mycelial biomass was increased three-fold as compared to glucose medium. In the presence of phospholipids, 155 mg l(-1) p-hydroxybenzaldehyde was produced as the major compound on culture day 13 with a molar yield of 26%. The degradation pathways of p-coumaric acid were investigated. Based on the different metabolites identified, an oxidative side-chain degradation pathway of p-coumaric acid conversion to p-hydroxybenzoic acid was suggested. This acid was further reduced to p-hydroxybenzaldehyde and p-hydroxybenzyl alcohol, or hydroxylated and reduced to protocatechyl derivatives. Additionally, a reductive pathway of p-coumaric acid with 3-(4-hydroxyphenyl)-propanol as the terminal product occurred.
Estrada Alvarado
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Unité INRA de Biotechnologie des Champignons Filamenteux, IFR de Biotechnologie Agro-Industrielle de Marseille, Universités de Provence et de la Méditerranée, ESIL, France. estrada@esil.univ-mrs.fr
Lomascolo
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A
Navarro
D
D
Delattre
M
M
Asther
M
M
Lesage-Meessen
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L
D000363:Agaricales / Q000254:growth & development / Q000378:metabolism*; D001547:Benzaldehydes / Q000737:chemistry / Q000378:metabolism*; D001709:Biotechnology; D001711:Biotransformation; D003373:Coumaric Acids / Q000737:chemistry / Q000378:metabolism*; D005421:Flavoring Agents / Q000302:isolation & purification / Q000378:metabolism; D007700:Kinetics; D008956:Models, Chemical; D010084:Oxidation-Reduction; D010743:Phospholipids / Q000378:metabolism; D011422:Propionates
D001547:Benzaldehydes; D003373:Coumaric Acids; D005421:Flavoring Agents; D010743:Phospholipids; D011422:Propionates; C495469:p-coumaric acid; C011483:4-hydroxybenzaldehyde