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Hj Bouwmeester - One of the best experts on this subject based on the ideXlab platform.
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Hydroxylation of sesquiterpenes by enzymes from Chicory (Cichorium intybus L.) Roots
Tetrahedron, 2003Co-Authors: Janwillem De Kraker, Maurice C R Franssen, Aede De Groot, Marloes Schurink, Wilfried A. König, Hj BouwmeesterAbstract:A microsomal enzyme preparation of Chicory Roots catalyses the hydroxylation of various sesquiterpene olefins in the presence of NADPH. Most of these hydroxylations take place at an isopropenyl or isopropylidene group. The number of products obtained from any of the substrates is confined to one or, in a few cases, two sesquiterpene alcohols. In addition, the conversion of (+)-valencene into nootkatone through β-nootkatol was observed. The involvement of (+)-germacrene A hydroxylase (a cytochrome P450 enzyme) and other enzymes of sesquiterpene lactone biosynthesis in these reactions is discussed.
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biosynthesis of germacrene a carboxylic acid in Chicory Roots demonstration of a cytochrome p450 germacrene a hydroxylase and nadp dependent sesquiterpenoid dehydrogenase s involved in sesquiterpene lactone biosynthesis
Plant Physiology, 2001Co-Authors: Janwillem De Kraker, Marcella C F Dalm, Maurice C R Franssen, Aede De Groot, Hj BouwmeesterAbstract:Sprouts of Chicory (Cichorium intybus), a vegetable grown in the dark, have a slightly bitter taste associated with the presence of guaianolides, eudesmanolides, and germacranolides. The committed step in the biosynthesis of these compounds is catalyzed by a (+)-germacrene A synthase. Formation of the lactone ring is the postulated next step in biosynthesis of the germacrene-derived sesquiterpene lactones. The present study confirms this hypothesis by isolation of enzyme activities from Chicory Roots that introduce a carboxylic acid function in the germacrene A isopropenyl side chain, which is necessary for lactone ring formation. (+)-Germacrene A is hydroxylated to germacra-1(10),4,11(13)-trien-12-ol by a cytochrome P450 enzyme, and is subsequently oxidized to germacra-1(10),4,11(13)-trien-12-oic acid by NADP+-dependent dehydrogenase(s). Both oxidized germacrenes were detected as their Cope-rearrangement products elema-1,3,11(13)-trien-12-ol and elema-1,3,11(13)-trien-12-oic acid, respectively. The cyclization products of germacra-1(10),4,11(13)-trien-12-ol, i.e. costol, were also observed. The (+)-germacrene A hydroxylase is inhibited by carbon monoxide (blue-light reversible), has an optimum pH at 8.0, and hydroxylates β-elemene with a modest degree of enantioselectivity.
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Biosynthesis of Germacrene A Carboxylic Acid in Chicory Roots. Demonstration of a Cytochrome P450 (+)-Germacrene A Hydroxylase and NADP+-Dependent Sesquiterpenoid Dehydrogenase(s) Involved in Sesquiterpene Lactone Biosynthesis
Plant Physiology, 2001Co-Authors: Janwillem De Kraker, Marcella C F Dalm, Maurice C R Franssen, Aede De Groot, Hj BouwmeesterAbstract:Sprouts of Chicory (Cichorium intybus), a vegetable grown in the dark, have a slightly bitter taste associated with the presence of guaianolides, eudesmanolides, and germacranolides. The committed step in the biosynthesis of these compounds is catalyzed by a (+)-germacrene A synthase. Formation of the lactone ring is the postulated next step in biosynthesis of the germacrene-derived sesquiterpene lactones. The present study confirms this hypothesis by isolation of enzyme activities from Chicory Roots that introduce a carboxylic acid function in the germacrene A isopropenyl side chain, which is necessary for lactone ring formation. (+)-Germacrene A is hydroxylated to germacra-1(10),4,11(13)-trien-12-ol by a cytochrome P450 enzyme, and is subsequently oxidized to germacra-1(10),4,11(13)-trien-12-oic acid by NADP+-dependent dehydrogenase(s). Both oxidized germacrenes were detected as their Cope-rearrangement products elema-1,3,11(13)-trien-12-ol and elema-1,3,11(13)-trien-12-oic acid, respectively. The cyclization products of germacra-1(10),4,11(13)-trien-12-ol, i.e. costol, were also observed. The (+)-germacrene A hydroxylase is inhibited by carbon monoxide (blue-light reversible), has an optimum pH at 8.0, and hydroxylates β-elemene with a modest degree of enantioselectivity.
Janwillem De Kraker - One of the best experts on this subject based on the ideXlab platform.
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Hydroxylation of sesquiterpenes by enzymes from Chicory (Cichorium intybus L.) Roots
Tetrahedron, 2003Co-Authors: Janwillem De Kraker, Maurice C R Franssen, Aede De Groot, Marloes Schurink, Wilfried A. König, Hj BouwmeesterAbstract:A microsomal enzyme preparation of Chicory Roots catalyses the hydroxylation of various sesquiterpene olefins in the presence of NADPH. Most of these hydroxylations take place at an isopropenyl or isopropylidene group. The number of products obtained from any of the substrates is confined to one or, in a few cases, two sesquiterpene alcohols. In addition, the conversion of (+)-valencene into nootkatone through β-nootkatol was observed. The involvement of (+)-germacrene A hydroxylase (a cytochrome P450 enzyme) and other enzymes of sesquiterpene lactone biosynthesis in these reactions is discussed.
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biosynthesis of germacrene a carboxylic acid in Chicory Roots demonstration of a cytochrome p450 germacrene a hydroxylase and nadp dependent sesquiterpenoid dehydrogenase s involved in sesquiterpene lactone biosynthesis
Plant Physiology, 2001Co-Authors: Janwillem De Kraker, Marcella C F Dalm, Maurice C R Franssen, Aede De Groot, Hj BouwmeesterAbstract:Sprouts of Chicory (Cichorium intybus), a vegetable grown in the dark, have a slightly bitter taste associated with the presence of guaianolides, eudesmanolides, and germacranolides. The committed step in the biosynthesis of these compounds is catalyzed by a (+)-germacrene A synthase. Formation of the lactone ring is the postulated next step in biosynthesis of the germacrene-derived sesquiterpene lactones. The present study confirms this hypothesis by isolation of enzyme activities from Chicory Roots that introduce a carboxylic acid function in the germacrene A isopropenyl side chain, which is necessary for lactone ring formation. (+)-Germacrene A is hydroxylated to germacra-1(10),4,11(13)-trien-12-ol by a cytochrome P450 enzyme, and is subsequently oxidized to germacra-1(10),4,11(13)-trien-12-oic acid by NADP+-dependent dehydrogenase(s). Both oxidized germacrenes were detected as their Cope-rearrangement products elema-1,3,11(13)-trien-12-ol and elema-1,3,11(13)-trien-12-oic acid, respectively. The cyclization products of germacra-1(10),4,11(13)-trien-12-ol, i.e. costol, were also observed. The (+)-germacrene A hydroxylase is inhibited by carbon monoxide (blue-light reversible), has an optimum pH at 8.0, and hydroxylates β-elemene with a modest degree of enantioselectivity.
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Biosynthesis of Germacrene A Carboxylic Acid in Chicory Roots. Demonstration of a Cytochrome P450 (+)-Germacrene A Hydroxylase and NADP+-Dependent Sesquiterpenoid Dehydrogenase(s) Involved in Sesquiterpene Lactone Biosynthesis
Plant Physiology, 2001Co-Authors: Janwillem De Kraker, Marcella C F Dalm, Maurice C R Franssen, Aede De Groot, Hj BouwmeesterAbstract:Sprouts of Chicory (Cichorium intybus), a vegetable grown in the dark, have a slightly bitter taste associated with the presence of guaianolides, eudesmanolides, and germacranolides. The committed step in the biosynthesis of these compounds is catalyzed by a (+)-germacrene A synthase. Formation of the lactone ring is the postulated next step in biosynthesis of the germacrene-derived sesquiterpene lactones. The present study confirms this hypothesis by isolation of enzyme activities from Chicory Roots that introduce a carboxylic acid function in the germacrene A isopropenyl side chain, which is necessary for lactone ring formation. (+)-Germacrene A is hydroxylated to germacra-1(10),4,11(13)-trien-12-ol by a cytochrome P450 enzyme, and is subsequently oxidized to germacra-1(10),4,11(13)-trien-12-oic acid by NADP+-dependent dehydrogenase(s). Both oxidized germacrenes were detected as their Cope-rearrangement products elema-1,3,11(13)-trien-12-ol and elema-1,3,11(13)-trien-12-oic acid, respectively. The cyclization products of germacra-1(10),4,11(13)-trien-12-ol, i.e. costol, were also observed. The (+)-germacrene A hydroxylase is inhibited by carbon monoxide (blue-light reversible), has an optimum pH at 8.0, and hydroxylates β-elemene with a modest degree of enantioselectivity.
Hans Gerhard Maier - One of the best experts on this subject based on the ideXlab platform.
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Volatile minor acids in coffee. III. Contents in Chicory Roots and barley malt
Deutsche Lebensmittel-rundschau, 1997Co-Authors: R. Woehrmann, M. Averbeck, Hans Gerhard MaierAbstract:The contents of 21 volatile monocarboxylic acids (from propanoic to pentadecanoic acid and some butenoic acids) have been determined in Chicory Roots and barley malt, dried and roasted each, by means of SDE and GC/FID. Identified and quantificated for the first time in green coffee are 12 acids each in dried Chicory, dried malt and roasted Chicory. 14 acids in roasted malt were identified and 16 were quantificated for the first time. The contents are lower than the literature values. Most of the contents increase during roasting, but not these of the most prevailing acids (tetradecanoic, pentadecanoic and hexanoic acids).
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Acids in Chicory Roots and malt: 3. Determination of acids present in the raw products and of their pyrolysis products
European Food Research and Technology, 1995Co-Authors: Handy Barlianto, Hans Gerhard MaierAbstract:Acids present in raw Chicory and dried malt as well as their decomposition products formed upon roasting were quantified in raw, dried and roasted Chicory Roots as well as in dried and roasted barley malt by gas liquid chromatography-mass spectrometry. Analysis showed the presence of 23 (malt) or 26 (Chicory) aliphatic acids including 2 amino acids and 11 (malt) or 12 (Chicory) aromatic acids. The composition of the two plant materials is almost equal qualitatively, but Chicory generally contains greater amounts of the acids. Citric, malic, phosphoric and pyroglutamic acids are the principal acids in Chicory Roots while phosphoric and pyroglutamic acids are the major acids in roasted malt. Compared to those of aliphatic acids, the concentrations of aromatic acids are relatively low. Chicory Roots contain relatively high amounts of 4-hydroxyphenylacetic, benzoic and 3,4-dihydroxycinnamic acids. In malt samples only traces of aromatic acids are present.
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Acids in Chicory Roots and malt. II: Determination of acids derived from carbohydrates
European Food Research and Technology, 1995Co-Authors: Handy Barlianto, Hans Gerhard MaierAbstract:Acids known to be decomposition products of carbohydrates were quantified in raw, dried and roasted Chicory Roots and in dried and roasted barley malt by means of gas liquid chromatography/mass spectrometry and isotachophoresis. Acids derived from other educts will be dealt with in following papers. Of the acids found, eight are of the aldonic type, ten are deoxyaldonic, three are oxo acids, two are derivatives of furanoic acid, two are volatile acids and the others are methyl succinic and oxalic acid. Qualitatively, Chicory and malt are composed of the same acids, but generally speaking the concentration of acids in Chicory is higher. While in the dried educts only trace amounts can be detected, the concentration of acids increases upon roasting. In roasted Chicory Roots considerably high contents of acetic, formic, glycolic, pyruvic, lactic, metasaccharinic, oxalic, glyceric and 3-hydroxypropionic acids were quantified. 5-Hydroxymethyl-2-furanoic, 2,4-dihydroxybutyric, 3,4-dihydroxybutyric, arabonic, gluconic, ribonic, erythronic, threonic, 4-oxovaleric, methyl succinic, 2-furanoic, mannonic, 3-deoxypentonic, saccharinic, isosaccbarinic, methyl glyceric and 2-oxovaleric acids are minor compounds. In malt samples only acetic, pyruvic, formic, oxalic and lactic acids were detected in relatively high concentrations. Gluconic, 3,4-dihydroxybutyric, 3-hydroxypropionic, metasaccharinic, mannonic, glyceric, glycolic, 2,4-dihydroxybutyric, ribonic, threonic, 5-hydroxymethyl-2-furanoic, erythronic, 4-oxovaleric, 2-furanoic, saccharinic, methyl succinic, arabonic, 3-deoxypentonic, methyl glyceric, 2-oxovaleric and isosaccharinic acids are minor compounds
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Acids in Chicory Roots and malt
European Food Research and Technology, 1994Co-Authors: Handy Barlianto, Hans Gerhard MaierAbstract:A determination method for non-volatile acids in roasted Chicory Roots and roasted barley malt is described. The clean-up was accomplished using preparative gel electrophoresis followed by gas chromatography (GC)/mass spectrometry of the methoximes (ketonic acids) or trimethylsilyl derivatives (all acids). Using these methods, 64 non-volatile acids have been identified in Chicory (among those 48 for the first time). In barley malt 60 acids could be detected (47 for the first time). Ten commercially unavailable substances have been synthesized. Most of the acids have been quantified using the same clean-up and GC/selected ion monitoring or GC/flame ionisation detection (FID). The recoveries range from 41 to 105% (average 79%), the detection limits from 1 to 72μg/kg being somewhat lower for the FID and considerably lower for malt, and the relative standard deviations from 1 to 10% for the main acids, from 2 to 89% for the minor acids and from 8 to 133% for the trace acids. In addition formic and acetic acids were determined by isotachophoresis.
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Suren der Zichorienwurzel@@@Acids of the Chicory root. IV. The balance of malic and citric acid during roasting: IV. Zur Bilanz vonl-pfelsure und Citronensure beim Rsten
European Food Research and Technology, 1993Co-Authors: Ulrike Jarms, Hans Gerhard Maier, Susanne HillmarAbstract:Malic and citric acids were determined by enzymatic analysis in a series of roasted Chicory Roots. The content of these acids decreased to about 30% with increasing degree of roast: 37% of the malic acid and 44% of the citric acid formed compounds with soluble and insoluble substances in the Chicory root. These compounds can be hydrolysed by alkali. According to model experiments they appeared to be esters. These esters represent the main products during roasting besides the products of dehydration and decarboxylation and volatile compounds
Maurice C R Franssen - One of the best experts on this subject based on the ideXlab platform.
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Hydroxylation of sesquiterpenes by enzymes from Chicory (Cichorium intybus L.) Roots
Tetrahedron, 2003Co-Authors: Janwillem De Kraker, Maurice C R Franssen, Aede De Groot, Marloes Schurink, Wilfried A. König, Hj BouwmeesterAbstract:A microsomal enzyme preparation of Chicory Roots catalyses the hydroxylation of various sesquiterpene olefins in the presence of NADPH. Most of these hydroxylations take place at an isopropenyl or isopropylidene group. The number of products obtained from any of the substrates is confined to one or, in a few cases, two sesquiterpene alcohols. In addition, the conversion of (+)-valencene into nootkatone through β-nootkatol was observed. The involvement of (+)-germacrene A hydroxylase (a cytochrome P450 enzyme) and other enzymes of sesquiterpene lactone biosynthesis in these reactions is discussed.
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biosynthesis of germacrene a carboxylic acid in Chicory Roots demonstration of a cytochrome p450 germacrene a hydroxylase and nadp dependent sesquiterpenoid dehydrogenase s involved in sesquiterpene lactone biosynthesis
Plant Physiology, 2001Co-Authors: Janwillem De Kraker, Marcella C F Dalm, Maurice C R Franssen, Aede De Groot, Hj BouwmeesterAbstract:Sprouts of Chicory (Cichorium intybus), a vegetable grown in the dark, have a slightly bitter taste associated with the presence of guaianolides, eudesmanolides, and germacranolides. The committed step in the biosynthesis of these compounds is catalyzed by a (+)-germacrene A synthase. Formation of the lactone ring is the postulated next step in biosynthesis of the germacrene-derived sesquiterpene lactones. The present study confirms this hypothesis by isolation of enzyme activities from Chicory Roots that introduce a carboxylic acid function in the germacrene A isopropenyl side chain, which is necessary for lactone ring formation. (+)-Germacrene A is hydroxylated to germacra-1(10),4,11(13)-trien-12-ol by a cytochrome P450 enzyme, and is subsequently oxidized to germacra-1(10),4,11(13)-trien-12-oic acid by NADP+-dependent dehydrogenase(s). Both oxidized germacrenes were detected as their Cope-rearrangement products elema-1,3,11(13)-trien-12-ol and elema-1,3,11(13)-trien-12-oic acid, respectively. The cyclization products of germacra-1(10),4,11(13)-trien-12-ol, i.e. costol, were also observed. The (+)-germacrene A hydroxylase is inhibited by carbon monoxide (blue-light reversible), has an optimum pH at 8.0, and hydroxylates β-elemene with a modest degree of enantioselectivity.
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Biosynthesis of Germacrene A Carboxylic Acid in Chicory Roots. Demonstration of a Cytochrome P450 (+)-Germacrene A Hydroxylase and NADP+-Dependent Sesquiterpenoid Dehydrogenase(s) Involved in Sesquiterpene Lactone Biosynthesis
Plant Physiology, 2001Co-Authors: Janwillem De Kraker, Marcella C F Dalm, Maurice C R Franssen, Aede De Groot, Hj BouwmeesterAbstract:Sprouts of Chicory (Cichorium intybus), a vegetable grown in the dark, have a slightly bitter taste associated with the presence of guaianolides, eudesmanolides, and germacranolides. The committed step in the biosynthesis of these compounds is catalyzed by a (+)-germacrene A synthase. Formation of the lactone ring is the postulated next step in biosynthesis of the germacrene-derived sesquiterpene lactones. The present study confirms this hypothesis by isolation of enzyme activities from Chicory Roots that introduce a carboxylic acid function in the germacrene A isopropenyl side chain, which is necessary for lactone ring formation. (+)-Germacrene A is hydroxylated to germacra-1(10),4,11(13)-trien-12-ol by a cytochrome P450 enzyme, and is subsequently oxidized to germacra-1(10),4,11(13)-trien-12-oic acid by NADP+-dependent dehydrogenase(s). Both oxidized germacrenes were detected as their Cope-rearrangement products elema-1,3,11(13)-trien-12-ol and elema-1,3,11(13)-trien-12-oic acid, respectively. The cyclization products of germacra-1(10),4,11(13)-trien-12-ol, i.e. costol, were also observed. The (+)-germacrene A hydroxylase is inhibited by carbon monoxide (blue-light reversible), has an optimum pH at 8.0, and hydroxylates β-elemene with a modest degree of enantioselectivity.
Aede De Groot - One of the best experts on this subject based on the ideXlab platform.
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Hydroxylation of sesquiterpenes by enzymes from Chicory (Cichorium intybus L.) Roots
Tetrahedron, 2003Co-Authors: Janwillem De Kraker, Maurice C R Franssen, Aede De Groot, Marloes Schurink, Wilfried A. König, Hj BouwmeesterAbstract:A microsomal enzyme preparation of Chicory Roots catalyses the hydroxylation of various sesquiterpene olefins in the presence of NADPH. Most of these hydroxylations take place at an isopropenyl or isopropylidene group. The number of products obtained from any of the substrates is confined to one or, in a few cases, two sesquiterpene alcohols. In addition, the conversion of (+)-valencene into nootkatone through β-nootkatol was observed. The involvement of (+)-germacrene A hydroxylase (a cytochrome P450 enzyme) and other enzymes of sesquiterpene lactone biosynthesis in these reactions is discussed.
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biosynthesis of germacrene a carboxylic acid in Chicory Roots demonstration of a cytochrome p450 germacrene a hydroxylase and nadp dependent sesquiterpenoid dehydrogenase s involved in sesquiterpene lactone biosynthesis
Plant Physiology, 2001Co-Authors: Janwillem De Kraker, Marcella C F Dalm, Maurice C R Franssen, Aede De Groot, Hj BouwmeesterAbstract:Sprouts of Chicory (Cichorium intybus), a vegetable grown in the dark, have a slightly bitter taste associated with the presence of guaianolides, eudesmanolides, and germacranolides. The committed step in the biosynthesis of these compounds is catalyzed by a (+)-germacrene A synthase. Formation of the lactone ring is the postulated next step in biosynthesis of the germacrene-derived sesquiterpene lactones. The present study confirms this hypothesis by isolation of enzyme activities from Chicory Roots that introduce a carboxylic acid function in the germacrene A isopropenyl side chain, which is necessary for lactone ring formation. (+)-Germacrene A is hydroxylated to germacra-1(10),4,11(13)-trien-12-ol by a cytochrome P450 enzyme, and is subsequently oxidized to germacra-1(10),4,11(13)-trien-12-oic acid by NADP+-dependent dehydrogenase(s). Both oxidized germacrenes were detected as their Cope-rearrangement products elema-1,3,11(13)-trien-12-ol and elema-1,3,11(13)-trien-12-oic acid, respectively. The cyclization products of germacra-1(10),4,11(13)-trien-12-ol, i.e. costol, were also observed. The (+)-germacrene A hydroxylase is inhibited by carbon monoxide (blue-light reversible), has an optimum pH at 8.0, and hydroxylates β-elemene with a modest degree of enantioselectivity.
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Biosynthesis of Germacrene A Carboxylic Acid in Chicory Roots. Demonstration of a Cytochrome P450 (+)-Germacrene A Hydroxylase and NADP+-Dependent Sesquiterpenoid Dehydrogenase(s) Involved in Sesquiterpene Lactone Biosynthesis
Plant Physiology, 2001Co-Authors: Janwillem De Kraker, Marcella C F Dalm, Maurice C R Franssen, Aede De Groot, Hj BouwmeesterAbstract:Sprouts of Chicory (Cichorium intybus), a vegetable grown in the dark, have a slightly bitter taste associated with the presence of guaianolides, eudesmanolides, and germacranolides. The committed step in the biosynthesis of these compounds is catalyzed by a (+)-germacrene A synthase. Formation of the lactone ring is the postulated next step in biosynthesis of the germacrene-derived sesquiterpene lactones. The present study confirms this hypothesis by isolation of enzyme activities from Chicory Roots that introduce a carboxylic acid function in the germacrene A isopropenyl side chain, which is necessary for lactone ring formation. (+)-Germacrene A is hydroxylated to germacra-1(10),4,11(13)-trien-12-ol by a cytochrome P450 enzyme, and is subsequently oxidized to germacra-1(10),4,11(13)-trien-12-oic acid by NADP+-dependent dehydrogenase(s). Both oxidized germacrenes were detected as their Cope-rearrangement products elema-1,3,11(13)-trien-12-ol and elema-1,3,11(13)-trien-12-oic acid, respectively. The cyclization products of germacra-1(10),4,11(13)-trien-12-ol, i.e. costol, were also observed. The (+)-germacrene A hydroxylase is inhibited by carbon monoxide (blue-light reversible), has an optimum pH at 8.0, and hydroxylates β-elemene with a modest degree of enantioselectivity.