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Isomeric Di-C-glycosylflavones in Fig (Ficus carica L.) Fred Siewek and Karl Herrmann Institut für Lebensm ittelchem ie der U niversität H annover, W unstorfer Str. 14, D-3000 Hannover 91 and Lutz Grotjahn and Victor Wray Gesellschaft für Biotechnologische Forschung, M ascheroder W eg 1, D-3300 Braunschweig Z. Naturforsch. 40c, 8 - 1 2 (1985); received Septem ber 6, 1984 Apigenin-di-C-glycosides, Isolation, Identification , Q uan tita tive D e term ination , Ficus carica Two isomeric C-glycosides o f apigenin (ap igen in-6-C -glucosyl-8-C -arab inoside

Notizen 949 The C-Glycosylflavone Pattern of Passiflora incamata L. Hans Geiger Institut für Chemie der Universität Hohenheim , Garbenstraße 30, D-7000 Stuttgart 70 and Kenneth R. Markham Chemistry Division, D .S .I .R ., Private Bag, Petone, New Zealand Z. Naturforsch. 41c, 949 — 950 (1986); received April 10, 1986 Passiflora incarnata L., Passifloraceae, Flavone-C-glycosides From the herbage of Passiflora incarnata have been iso­ lated eight flavone-C-glycosides based on apigenin and luteolin, six o f them had not been found before in that plant. The

1084 Notizen Investigations on H oya species. VIII*. Leaf Flavonols and Di-C-glycosylflavones Gerard J. Niemann Botanisch Laboratorium, Rijksuniversiteit Utrecht, Lange Nieuwstraat 106, 3512 PN Utrecht. Georgette Dellamonica and Jean Chopin Laboratoire de Chimie Biologique, University Claude Bernard, 43, Bd. du 11 Novembre, 69622 Villeurbanne Z. Naturforsch. 36 c, 1084-1085 (1981); received August 5, 1981 Hoya, Asclepiadaceae, Di-C-glycosylflavone, Flavonol, Chemotaxonomy Nine Hoya species were investigated for their leaf flavonoids. Four species contained

A New Flavone O-Glycoside and Other Constituents from Wheat Leaves (Triticum aestivum L.) Lene H. Harder and Lars P. Christensen* Department of Fruit, Vegetable and Food Science, Danish Institute of Agricultural Sciences, Kirstinebjergvej 10, DK-5792 Aarslev, Denmark. Fax: + 45-63 90 43 95. E-mail: larsp.christensen@agrsci.dk * Author for correspondence and reprint requests Z. Naturforsch. 55c, 337-340 (2000); received February 24/March 10, 2000 Triticum aestivum, Gramineae, C-Glycosylflavones From leaves of Triticum aestivum a new O-glycosylflavone has been

primary leaves, and 3 cm segments were floated on radioactive phenylalanine or cinnamic acid solutions, more than 90 per cent of the radioactivity was incorporated within 3 to 7 h depending on the developmental stage of the leaf. C-glycosylflavones were labelled within 15 min and radioactivity in these compounds increased for several hours. Pulse labelling and pulse chase experiments with either phenylalanine or cinnamic acid, unequivocally demonstrate that oat flavones are stable end products of metabolism. However, this procedure does not distinguish between

from spectroscopic studies. Determination of configu- rations was achieved by circular dichroism. Key words: Pelargonium sidoides, Phenol Glucoside, Coumarins, C-Glycosylflavones, Dihydroflavonols Introduction Pelargonium sidoides DC (Geraniaceae) is a herba- ceous commonly black-flowered perennial with a tuberous rootstock. This species is predominantly found over large parts of the interior of southern Africa, but also occurs in coastal mountain ranges [1, 2]. The roots of the plant are highly estimated in a number of medical systems of ethnic groups, includ- ing

the accum ula­ tion o f rutin, and to an about 30 percent increase, on the average, in the accumulation o f C-glycosylflavones in the treated material during its posttreatment incubation in the dark. When the treated cotyledons were incubated in a solution o f L-phenylalanine anthocyanin accumulation in the dark practically attained the same high level as it was observed in the illuminated cotyledons fed with exogenous L-phenylalanine. In experiments with 14C-labelled L-phenylalanine kinetin induced a sharp rise in the labelling (resp. in the utilization o f

parts of Achillea nobilis resulted in the isolation of 10 flavonoids. A new C-glycosylflavone, luteolin-6-C-apiofuranosyl-(1 52)-glucoside, was isolated besides orientin, isoorientin, vitexin, isoschaftoside, luteolin- 7-O--glucuronide, luteolin-4-O--glucoside and quercetin-3-O-methyl ether and two rare flavonolglycosides, quercetin-3-O-α-arabinosyl-(156)-glucoside and quercetin-3-O-methy- lether-7-O--glucoside. The structures were established either by comparison with authentic substances or by UV, 1H NMR and 13C NMR spectroscopic methods including 2d-NMR techniques

-tyrosine. Glyphosate (10~4- 10-2 m), when used for an additional treatment, was applied continu­ ously with tyrosine (10~3 m). All experiments were run in triplicate, and the results were subjected to statistical evaluation by Student’s significance test. M. Margna et al. • L-Tyrosine as a Precursor for Building Flavonoids in Buckwheat Cotyledons 155 F lavonoid a ssay a n d ra d io a c tiv ity m ea su rem en ts Anthocyanins were determined photometrically, rutin and individual C-glycosylflavones likewise after their separation by two-dimensional paper chromatography as

"-0-Arabinoside, Ontogeny Two further loci can be added to the three already known (g , g l and f g ) in Silene controlling the 7 -0 and 2"-0-glycosylation o f the C-glycosylflavone isovitexin (6-C-glucosylapigenin). These loci, 0 7 g for the 7-O-galactosylation and D6a for the 2"-0-arabinosylation, appear only to be expressed in cotyledons and rosette leaves and control the biosynthesis o f isovitexin 7 -0 - galactoside and isovitexin 7-0-galactose 2"-0-arabinoside in these parts o f plants in which the recessive alleles o f the loci g, g l and f g are homozygous