Conversion of Flavanone to Flavone, Dihydroflavonol and Flavonol with an Enzyme System from Cell Cultures of Parsley
نویسندگان
چکیده
Soluble enzyme preparations from irradiated cell suspension cultures of parsley (Petroselinum hortense Hoffm.) catalyse the conversion of flavanone to flavone, dihydroflavonol and flavonol. These reactions require 2-oxoglutarate, Fe2+ and ascorbate as cofactors. In the presence of these cofactors conversion of dihydroflavonol to flavonol was also observed. With this system in vitro biosynthesis of radioactive flavone, dihydroflavonol and flavonol from [2-14C]malonyl-CoA and 4-coumaroyl-CoA in good yield and with high specific activity is possible. We postulate that synthesis of flavone and flavonol from flavanone proceeds via 2-hydroxyand 2,3-dihydroxyflavanone, respectively, with subsequent dehydration. The microsomal fraction of the parsley cells contains an NADPH-dependent flavanone 3'hydroxylase.
منابع مشابه
Enzymes of General Phenylpropanoid Metabolism and of Flavonoid Glycoside Biosynthesis in Parsley: Differential Inducibility by Light during the Growth of Cell Suspension Cultures.
Several enzymes of phenylpropanoid metabolism showed large changes in their inducibility by light during the growth cycle of cell suspension cultures from parsley (Petroselinum hortense Hoffm.). Two of the three enzymes of general phenylpropanoid metabolism (group I) and six of the approximately 13 enzymes of the flavone and flavonol glycoside pathways (group II) were investigated. Both enzymes...
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