title: Biotransformation of caffeoyl quinic acids from green coffee extracts by Lactobacillus johnsonii NCC 533.
abstract: The potential of Lactobacillus johnsonii NCC 533 to metabolize chlorogenic acids from green coffee extract was investigated. Two enzymes, an esterase and a hydroxycinnamate decarboxylase (HCD), were involved in this biotransformation. The complete hydrolysis of 5-caffeoylquinic acid (5-CQA) into caffeic acid (CA) by L. johnsonii esterase occurred during the first 16 h of reaction time. No dihydrocaffeic acid was identified in the reaction mixture. The decarboxylation of CA into 4-vinylcatechol (4-VC) started only when the maximum concentration of CA was reached (10 μmol/ml). CA was completely transformed into 4-VC after 48 h of incubation. No 4-vinylphenol or other derivatives could be identified in the reaction media. In this study we demonstrate the capability of L. johnsonii to transform chlorogenic acids from green coffee extract into 4-VC in two steps one pot reaction. Thus, the enzymatic potential of certain lactobacilli might be explored to generate flavor compounds from plant polyphenols.
authors.affiliation: Nestec Ltd, Nestlé Research Centre, Vers-chez-les-Blanc, P.O. Box 44, Lausanne 26, 1000, Switzerland.
authors.forename: Rachid
authors.initials: R
authors.lastname: Bel-Rhlid
authors.affiliation: Rowett Institute of Nutrition and Health Gut, Health/Microbial Biochemistry, University of Aberdeen, Greenburn Road, Bucksburn, Aberdeen, AB21 9SB, Scotland.
authors.forename: Dinesh
authors.initials: D
authors.lastname: Thapa
authors.affiliation: Nestec Ltd, Nestlé Research Centre, Vers-chez-les-Blanc, P.O. Box 44, Lausanne 26, 1000, Switzerland.
authors.forename: Karin
authors.initials: K
authors.lastname: Kraehenbuehl
authors.affiliation: Nestec Ltd, Nestlé Research Centre, Vers-chez-les-Blanc, P.O. Box 44, Lausanne 26, 1000, Switzerland.
authors.forename: Carl Erik
authors.initials: CE
authors.lastname: Hansen
authors.affiliation: Institute of Food Science and Biotechnology, Faculty of Natural Sciences, University of Hohenheim (Stuttgart), Garbenstr. 25, Stuttgart, D-70593, Germany.
authors.forename: Lutz
authors.initials: L
authors.lastname: Fischer
keywords: 4-vinylcatechol; Chlorogenic acid; Decarboxylase; Esterase; L. johnsonii