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Blood lipid levels in rats with hyperlipidemia resulting from high-fat feeding were determined after ip administration of an MeOH extract of Prunus davidiana stems and its flavonoid components, (+)-catechin, prunin (= naringenin 7-O-glucoside), and hesperetin 5-O-glucoside. Administration of the MeOH extract for 3 days produced a significant decrease of blood triglyceride and total cholesterol, and the atherogenic index was also improved. (+)-Catechin was shown to be effective in reducing the elevated level of triglyceride. Prunin and hesperetin 5-O-glucoside did not show such an effect in high-fat-fed hypertriglyceridemic rats, but they did exhibit a significant hypocholesterolemic effect.

Extracts from Ulex europaeus L. (Fabaceae) were tested for antiviral activity against HSV-1 and poliovirus. It was found that the n-butanolic extract significantly inhibited the replication of these viruses, as shown by inhibition of cytophathic effects and reduction of plaques; the extract has neither a prophylactic nor a virucidal activity. From this extract has been isolated and identified by chromatographic, chemical, and spectroscopic methods, the 5-O-methylgenistein 7-O-beta D-glucopyranoside. This isoflavonic glycoside has not been previously described and it is responsible at least partially for the antiviral activity.

Two new flavonol glycosides from the seeds of Chenopodium quinoa have been isolated. Their structures were established as kaempferol 3-apiofuranosyl(1"'----2")rhamnopyranosyl(1""----6")galactoside and kaempferol 3-apiofuranosyl(1"'----2")rhamnopyranosyl(1""----6")galactoside. The main flavonoid glycoside was kaempferol 3-(2,6-dirhamnopyranosyl)galactoside.

Leaves of Hosta ventricosa yielded eight kaempferol glycosides, of which six: the 3-(2G-glucosylrutinoside)-7-glucoside, 3-sophoroside-7-glucoside, 3-rutinoside-7-glucoside, 3-(2G-glucosylrutinoside), 3-sophoroside, 3-rutinoside were fully characterized and two: the 3-xylosylrutinoside-7-glucoside and 3-xylosylrutinoside were tentatively identified. Investigations included 1H-1H COSY and 1H-1H 2D J NMR analysis.

Two new flavonol glycosides were isolated from the roots and rhizomes of Vancouveria hexandra. The glycosides were determined by chemical and spectral means to be anhydroicaritin 3-galactosyl(1----3) rhamnoside-7-glucoside and anhydroicaritin 3-[6-O-acetyl-galactosyl(1----3)rhamnoside]-7-glucoside.

Eight flavone glycosides were isolated from fronds of Asplenium normale, its two varieties, var. boreale and var. shimurae, and related species, A. oligophlebium. Six of the glycosides were identified: apigenin 7-O-dirhamnoside and 7-O-glucosylrhamnoside, luteolin 7-O-dirhamnoside and 7-O-glucosylrhamnoside, genkwanin 4'-O-glucosylrhamnoside, and vicenin-2. The remaining two glycosides were tentatively characterized as genkwanin 4'-O-glycoside and 6,8-di-C-glycosylluteolin. The four taxa analysed in this survey all had distinctive flavonoid profiles.

Two unusual diglycosides, quercetin and kaempferol 3-rhamnosyl(1----2)galactosides and the new isorhamnetin 3-rhamnosyl(1----2)galactoside have been isolated from the aerial parts of Blackstonia perfoliata. Instead of C-glycosylflavones, the occurrence of flavonol glycosides in this species as well as in three other genera of the Gentianaceae: Centaurium, Coutoubea and Eustoma, is in agreement with the grouping of these four genera in the subtribe Chlorae of the Gentianeae.

Three new flavonol triglycosides quercetin, kaempferol and isorhamnetin 3-rhamnosyl(1----2)galactoside-7-glucosides have been isolated from leaves and stems of Blackstonia perfoliata. This species together with three other genera of the tribe Gentianeae, subtribe Chlorae: Centaurium, Coutoubea and Eustoma, is unusual in producing flavonol glycosides instead of C-glycosyl flavones, the more characteristic flavonoid constituents of the Gentianaceae.

Some drugs effective against influenza contain flavonoids. We therefore examined the antiviral effect of hesperidin, hesperidinmethylchalcon, trihydroxyethylrutin, catechol, quercitrin, rutin and aurantiin against vesicular stromatitis virus (VSV) action on mouse fibroblasts and that of hesperidin against influenza virus in HeLa cells system by means of dye uptake measurements (Finter) and by plaque reduction test, respectively. Preincubation of the cells with the flavonoids 6--8 h before virus addition was inevitable. Protection of cells against virus action persisted for about 24 h and it abruptly disappeared after an addition of hyaluronidase. Maximal inhibition of virus action was achieved with a concentration of 200 microgram/ml flavonoid.

The flavonoid constituents of carrot leaves (Daucus carota L. ssp. sativa) were separated by means of cellulose column chromatography, and the following compounds were obtained crystalline and identified by usual procedures: luteolin 7-beta-D-glucoside as the main flavon, luteolin 4'-beta-D-glucoside, luteolin 7-beta-D-glucuronide, apigenin 7-beta-D-glucoside, apigenin 7-rutinoside, chrysoeriol 7-beta-D-glucoside. Luteolin 7-rutinoside also was identified, but could not be obtained crystalline.

The 1 M-KOH extract from the depectinated cell walls of parenchymatous tissues of mature runner bean (Phaseolus coccineus) on neutralization, dialysis and concentration gave insoluble (hemicellulose A) and soluble (hemicellulose B) carbohydrate complexes in the weight ratio 2:1. Both fractions contained polysaccharide, protein and polyphenolic material. The structural features of the carbohydrates were examined by methylation analysis. Hemicellulose A contained mainly pectic arabinogalactan, with lesser amounts of arabinoxylan and glucan. Sequential fractionation of hemicellulose B by anion-exchange and hydroxyapatite chromatography gave a range of polysaccharide-protein-polyphenolic complexes. The main polysaccharides in these complexes were (acidic) arabinoxylans, galactans, arabinogalactans 1 and 2 and xyloglucans. The proteins contained small amounts of hydroxyproline, but were rich in aspartic acid and glutamic acid. Attempts to determine the nature of the polyphenolic material were unsuccessful. The structural features of the polysaccharide-protein-polyphenolic complexes are discussed in relation to the structure of the cell walls of parenchymatous tissues.

Inhibitors of delta 4-3-ketosteroid (5 alpha) reductase, which had been prepared from rat prostate and converted testosterone to 5 alpha-dihydrotestosterone and 4-androstene-3,17-dione, were isolated from 50% ethanol extract of Populus nigra. They were identified as pinobanksin (I, 3,5,7-trihydroxyflavanone), 3,7-dimethylquercetin (II, 3',4',5-trihydroxy-3,7-dimethoxyflavone) and pinocembrin (III, 5,7-dihydroxyflavanone). Compound III showed the most potent inhibitory activity among them.

The flavonoid constituents of various spices were separated by means of chromatography on cellulose colums, and the following compounds were obtained crystalline: Quercetin 3-glucuronide from caraway, fennel, anise, and coriander; isoquercitrin from caraway and fennel; rutin from fennel and anise; quercetin 3-O-caffeylglucoside and kaempferol 3-glucoside from caraway; quercetin 3-arabinoside from fennel, and luteolin 7-glucoside, isoorientin and isovitexin from anise. Other constitutents which were however not obtained crystalline, but which could be identified by the usual procedures were kaempferol 3-glucuronide and kaempferol 3-arabinoside in fennel, apigenin 7-glucoside and a luteolin glycoside in anise, and isoquercitrin and rutin in coriander. The glycosides contained in the fruit of the four spices also occur in the leaves. Leaves of caraway and fennel in addition contain isorhammetin glycosides in low concentration.

A thermospray liquid chromatography-mass spectrometry interface connected to a double-focusing magnetic sector instrument has been applied successfully to the solution of a number of analytical problems in food and agricultural research. Examples of the qualitative analysis of some anti-nutrients, plant growth control hormones, biotechnology products and a plant polyphenol are presented and discussed.

The development of a qualitative and quantitative method of determination for glycosides of flavones, flavonols and flavanones and their aglycones by means of high pressure liquid chromatography is described. Silicagel LiChrosorb Si 60 is used as stationary phase, as well as various eluents at different temperatures. The compounds are acetylated. An extract of plum leaves serves as example of application.