title: Coupled hydroperoxide lyase and alcohol dehydrogenase for selective synthesis of aldehyde or alcohol.
abstract: The main objective of this work was to improve the selective synthesis of a volatile compound: aldehyde or alcohol using a coupled-enzyme system. A novel method of synthesis of C6-aldehyde or alcohol was carried out in the presence of hydroperoxide lyase (HPLS) activity coupled to alcohol dehydrogenase (ADH) activity. After cleavage of the initial substrate, hydroperoxy fatty acid catalyzed by HPLS, the second enzyme, ADH, can catalyze the reduction of the aldehyde to the corresponding alcohol, or the oxidation of contaminating alcohol into aldehyde, depending on the cofactor present in the medium (oxidized or reduced form). We succeeded in improving the synthesis of one of the products. When coupling HPLS to NADP, the selectivity of hexanal production from 13-hydroperoxy linoleic acid was improved, and hexanol production was reduced 5 to 10 times after 15 min of reaction at 15 degrees C and pH 7.0. In another experiment, HPLS was coupled to ADH in the presence of NADH. The production of alcohol (hexenols) was then favored especially when using 13-hydroperoxy linolenic acid as substrate at concentrations >15 mM, reaching 95% of the products. Coupling of the enzymatic reactions (cleavage reduction) not only reduced the number of steps but also allowed us to increase the conversion rate of the initial substrate (hydroperoxy fatty acid). Structures of the compounds produced in this work were confirmed using gas chromatography-mass spectroscopy analysis. Each of these products has its own delicately different fresh odor that can be used in various applications.
authors.affiliation: Department of Biological and Chemical Engineering, National Institute of Applied Science and Technology, BP 676, 1080 Tunis Cedex, Tunisia. mohamed.gargouri@insat.rnu.tn
authors.forename: Mohamed
authors.initials: M
authors.lastname: Gargouri
authors.forename: Najla Ben
authors.initials: NB
authors.lastname: Akacha
authors.forename: Marie-Dominique
authors.initials: MD
authors.lastname: Legoy
mesh_terms: D000426:Alcohol Dehydrogenase / Q000737:chemistry*; D000438:Alcohols / Q000138:chemical synthesis; D000446:Aldehyde-Lyases / Q000737:chemistry*; D000447:Aldehydes / Q000138:chemical synthesis*; D003067:Coenzymes / Q000737:chemistry; D003577:Cytochrome P-450 Enzyme System / Q000737:chemistry*; D004789:Enzyme Activation; D000441:Hexanols / Q000138:chemical synthesis*; D009097:Multienzyme Complexes / Q000737:chemistry; D013379:Substrate Specificity
chemical_list: D000438:Alcohols; D000447:Aldehydes; D003067:Coenzymes; D000441:Hexanols; D009097:Multienzyme Complexes; D003577:Cytochrome P-450 Enzyme System; D000426:Alcohol Dehydrogenase; D000446:Aldehyde-Lyases; C054540:hydroperoxide lyase