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Sueharu Horinouchi - One of the best experts on this subject based on the ideXlab platform.

  • Efficient production of (2S)-flavanones by Escherichia coli containing an artificial biosynthetic gene cluster
    Applied Microbiology and Biotechnology, 2005
    Co-Authors: Ikuo Miyahisa, Nobutaka Funa, Hisashi Kawasaki, Yasuo Ohnishi, Masafumi Kaneko, Hiroyuki Kojima, Sueharu Horinouchi
    Abstract:

    For the fermentative production of plant-specific flavanones (naringenin, pinocembrin) by Escherichia coli, a plasmid was constructed which carried an artificial biosynthetic gene cluster, including PAL encoding a phenylalanine ammonia-lyase from a yeast, ScCCL encoding a cinnamate/coumarate:CoA ligase from the actinomycete Streptomyces coelicolor A3(2), CHS encoding a chalcone synthase from a licorice plant and CHI encoding a chalcone isomerase from the Pueraria plant. The recombinant E. coli cells produced (2S)-naringenin from tyrosine and (2S)-pinocembrin from phenylalanine. When the two subunit genes of acetyl-CoA carboxylase from Corynebacterium glutamicum were expressed under the control of the T7 promoter and the ribosome-binding sequence in the recombinant E. coli cells, the flavanone yields were greatly increased, probably because enhanced expression of acetyl-CoA carboxylase increased a pool of malonyl-CoA that was available for flavanone synthesis. Under cultural conditions where E. coli at a cell density of 50 g/l was incubated in the presence of 3 mM tyrosine or phenylalanine, the yields of naringenin and pinocembrin reached about 60 mg/l. The fermentative production of flavanones in E. coli is the first step in the construction of a library of flavonoid compounds and un-natural flavonoids in bacteria. © Springer-Verlag 2005.

  • Production of plant-specific flavanones by Escherichia coli containing an artificial gene cluster
    Applied and Environmental Microbiology, 2003
    Co-Authors: Eui Il Hwang, Yoshito Ohnishi, Masafumi Kaneko, Sueharu Horinouchi
    Abstract:

    In plants, chalcones are precursors for a large number of flavonoid-derived plant natural products and are converted to flavanones by chalcone isomerase or nonenzymatically. Chalcones are synthesized from tyrosine and phenylalanine via the phenylpropanoid pathway involving phenylalanine ammonia lyase (PAL), cinnamate-4-hydroxylase (C4H), 4-coumarate:coenzyme A ligase (4CL), and chalcone synthase (CHS). For the purpose of production of flavanones in Escherichia coli, three sets of an artificial gene cluster which contained three genes of heterologous origins--PAL from the yeast Rhodotorula rubra, 4CL from the actinomycete Streptomyces coelicolor A3(2), and CHS from the licorice plant Glycyrrhiza echinata--were constructed. The constructions of the three sets were done as follows: (i) PAL, 4CL, and CHS were placed in that order under the control of the T7 promoter (P(T7)) and the ribosome-binding sequence (RBS) in the pET vector, where the initiation codons of 4CL and CHS were overlapped with the termination codons of the preceding genes; (ii) the three genes were transcribed by a single P(T7) in front of PAL, and each of the three contained the RBS at appropriate positions; and (iii) all three genes contained both P(T7) and the RBS. These pathways bypassed C4H, a cytochrome P-450 hydroxylase, because the bacterial 4CL enzyme ligated coenzyme A to both cinnamic acid and 4-coumaric acid. E. coli cells containing the gene clusters produced two flavanones, pinocembrin from phenylalanine and naringenin from tyrosine, in addition to their precursors, cinnamic acid and 4-coumaric acid. Of the three sets, the third gene cluster conferred on the host the highest ability to produce the flavanones. This is a new metabolic engineering technique for the production in bacteria of a variety of compounds of plant and animal origin.

M. Suschetet - One of the best experts on this subject based on the ideXlab platform.

  • flavonoids of honey and propolis characterization and effects on hepatic drug metabolizing enzymes and benzo a pyrene dna binding in rats
    Journal of Agricultural and Food Chemistry, 1996
    Co-Authors: Marie-hélène Siess, Sylvie Aubert, Marie-jo Amiot, S. Sabatier, Mariechantal Canivenclavier, M. Suschetet
    Abstract:

    The influence of dietary sunflower honey, propolis, and a flavonoid extract of propolis was examined on drug-metabolizing enzyme activities in rat liver and on microsome-mediated binding of benzo[a]pyrene to DNA. Characterization of flavonoids present in sunflower honey and propolis was achieved in order to assess the relative effects of different components of honey and propolis. Honey and propolis contained the same major flavonoids, pinocembrin, chrysin, galangin, and pinobanksin. The concentration of flavonoids was higher in propolis. Sunflower honey produced no significant changes on phase I and phase II enzyme activities and no modification of in vitro binding of benzo[a]pyrene to DNA. Propolis treatment produced an increase of ethoxyresorufin deethylase, pentoxyresorufin depentylase, ethoxycoumarin deethylase, glutathione transferase, and epoxide hydrolase activities. A flavonoid extract from propolis slightly enhanced only few enzyme activities, ethoxycoumarin deethylase and epoxide hydrolase. The...

  • Flavonoids of Honey and Propolis : Characterization and Effects on Hepatic Drug-Metabolizing Enzymes and Benzo [a] pyrene-DNA Binding in Rats.
    J. Agric. Food Chem, 1996
    Co-Authors: Marie-hélène Siess, M C Canivenc-lavier, Anne Marie Le Bon, Sylvie Aubert, Sylvie Sabatier, Marie-jo Amiot, M. Suschetet
    Abstract:

    The influence of dietary sunflower honey, propolis, and a flavonoid extract of propolis was examined on drug-metabolizing enzyme activities in rat liver and on microsome-mediated binding of benzo- [a]pyrene to DNA. Characterization of flavonoids present in sunflower honey and propolis was achieved in order to assess the relative effects of different components of honey and propolis. Honey and propolis contained the same major flavonoids, pinocembrin, chrysin, galangin, and pinobanksin. The concentration of flavonoids was higher in propolis. Sunflower honey produced no significant changes on phase I and phase II enzyme activities and no modification of in vitro binding of benzo- [a]pyrene to DNA. Propolis treatment produced an increase of ethoxyresorufin deethylase, pentoxyresorufin depentylase, ethoxycoumarin deethylase, glutathione transferase, and epoxide hydrolase activities. A flavonoid extract from propolis slightly enhanced only few enzyme activities, ethoxycoumarin deethylase and epoxide hydrolase. The induction pattern was similar to that observed with pinocembrin (a major flavonoid of propolis) administered solely. Binding of benzo- [a]pyrene to DNA by microsomes from rats fed with propolis or a flavonoid extract from propolis was not significantly modified. These results contribute to identification of food or foodstuffs that can modify drug-metabolizing enzymes and binding of carcinogens to DNA.

Mattheos A G Koffas - One of the best experts on this subject based on the ideXlab platform.

  • Biosynthesis of natural flavanones in Saccharomyces cerevisiae
    Applied and Environmental Microbiology, 2005
    Co-Authors: Yajun Yan, Abhijeet Kohli, Mattheos A G Koffas
    Abstract:

    A four-step flavanone biosynthetic pathway was constructed and introduced into Saccharomyces cerevisiae. The recombinant yeast strain was fed with phenylpropanoid acids and produced the flavanones naringenin and pinocembrin 62 and 22 times more efficiently compared to previously reported recombinant prokaryotic strains. Microbial biosynthesis of the flavanone eriodictyol was also achieved.

Rachel Mata - One of the best experts on this subject based on the ideXlab platform.

  • Pinocembrine a bioactive flavanone from teloxys graveolens
    Journal of Ethnopharmacology, 1991
    Co-Authors: Maria Del Rayo Camacho, Berta Sanchez, Hector Quiroz, Jose L Contreras, Rachel Mata
    Abstract:

    Bioactivity directed fractionation of the acetone extract of Teloxys graveolens (Willd.) Weber (Chenopodiaceae), using the brine shrimp lethality test, led to the isolation of 5,7-dihydroxyflavanone (Pinocembrine) (lc50 = 4.25 μg/ml) as the only active compound. Pinocembrine also exhibited fasciolicide, ovicide and larvicide activities on newly excysted Fasciola hepatica, on infective eggs of Ascaridi galli and on stage three larvae of Stomoxys calcitrans, respectively.

Marie-jo Amiot - One of the best experts on this subject based on the ideXlab platform.

  • flavonoids of honey and propolis characterization and effects on hepatic drug metabolizing enzymes and benzo a pyrene dna binding in rats
    Journal of Agricultural and Food Chemistry, 1996
    Co-Authors: Marie-hélène Siess, Sylvie Aubert, Marie-jo Amiot, S. Sabatier, Mariechantal Canivenclavier, M. Suschetet
    Abstract:

    The influence of dietary sunflower honey, propolis, and a flavonoid extract of propolis was examined on drug-metabolizing enzyme activities in rat liver and on microsome-mediated binding of benzo[a]pyrene to DNA. Characterization of flavonoids present in sunflower honey and propolis was achieved in order to assess the relative effects of different components of honey and propolis. Honey and propolis contained the same major flavonoids, pinocembrin, chrysin, galangin, and pinobanksin. The concentration of flavonoids was higher in propolis. Sunflower honey produced no significant changes on phase I and phase II enzyme activities and no modification of in vitro binding of benzo[a]pyrene to DNA. Propolis treatment produced an increase of ethoxyresorufin deethylase, pentoxyresorufin depentylase, ethoxycoumarin deethylase, glutathione transferase, and epoxide hydrolase activities. A flavonoid extract from propolis slightly enhanced only few enzyme activities, ethoxycoumarin deethylase and epoxide hydrolase. The...

  • Flavonoids of Honey and Propolis : Characterization and Effects on Hepatic Drug-Metabolizing Enzymes and Benzo [a] pyrene-DNA Binding in Rats.
    J. Agric. Food Chem, 1996
    Co-Authors: Marie-hélène Siess, M C Canivenc-lavier, Anne Marie Le Bon, Sylvie Aubert, Sylvie Sabatier, Marie-jo Amiot, M. Suschetet
    Abstract:

    The influence of dietary sunflower honey, propolis, and a flavonoid extract of propolis was examined on drug-metabolizing enzyme activities in rat liver and on microsome-mediated binding of benzo- [a]pyrene to DNA. Characterization of flavonoids present in sunflower honey and propolis was achieved in order to assess the relative effects of different components of honey and propolis. Honey and propolis contained the same major flavonoids, pinocembrin, chrysin, galangin, and pinobanksin. The concentration of flavonoids was higher in propolis. Sunflower honey produced no significant changes on phase I and phase II enzyme activities and no modification of in vitro binding of benzo- [a]pyrene to DNA. Propolis treatment produced an increase of ethoxyresorufin deethylase, pentoxyresorufin depentylase, ethoxycoumarin deethylase, glutathione transferase, and epoxide hydrolase activities. A flavonoid extract from propolis slightly enhanced only few enzyme activities, ethoxycoumarin deethylase and epoxide hydrolase. The induction pattern was similar to that observed with pinocembrin (a major flavonoid of propolis) administered solely. Binding of benzo- [a]pyrene to DNA by microsomes from rats fed with propolis or a flavonoid extract from propolis was not significantly modified. These results contribute to identification of food or foodstuffs that can modify drug-metabolizing enzymes and binding of carcinogens to DNA.

  • Gas chromatography-mass spectrometry analysis of flavonoids in honey
    Sciences Des Aliments, 1993
    Co-Authors: T. Berahia, C. Cerrati, S. Sabatier, Marie-jo Amiot
    Abstract:

    L'analyse des flavonoides extraits du miel sans derivation a ete realisee par chromatographie en phase gazeuse couplee a la spectrometrie de masse (CG/SM). Cette technique a permis d'identifier 6 flavone-flavonol et 4 flavanone-flavanonols. Le flanonoide majoritaire a ete identifie a la Pinocembrine. Le programme lon collect dialog box a permis de detecter les flovonoides minoritaires, telle la flavone. L'analyse des flavonoides des miels par CG/SM permettrait de determiner leur origine florale