Showing papers in "Phytochemistry in 1990"

TL;DR: In this paper, the content and type of linkage of p-coumaric (PCA) and FA in Bjorkman lignins and fractions obtained during their purification were compared in extract-free, ball-milled wheat internode walls, with and without, prior saponification with 0.5 M sodium hydroxide at room temperature.

TL;DR: The 1H and 13C NMR spectra of sitosterol, stigmasterol, Stigmast-7-en-3β-ol and spinasterol have been unambiguously assigned by use of HOMCOR and HETCOR techniqeus as discussed by the authors.

TL;DR: In this article, a 1:1 pigment-co-pigment complexes forced together by hydrophobic interactions with chlorogenic acid in aqueous solutions were studied. But the extent of pigment-coloring association is under the control of the unique hydrogen-bonded molecular structure of liquid water, and is affected by pH, temperature and composition of the medium.

TL;DR: Increase in 4-aminobutyrate content and glutamate decarboxylase activity have been observed in many plants under a variety of environmental stress conditions.

TL;DR: The progress during the last 10 years in the biotransformation of exogenous substrates administered to plant cell cultures is outlined and the development of techniques using immobilized plant cells are delineated.

TL;DR: Three proteases (cynarases 1, 2 and 3) with milk-clotting activity have been purified from dried flowers of Cynara cardunculus andhibitor studies indicate that the cynarases are of the aspartic acid type.

TL;DR: In this article, the pericarp of unripe and ripe tomatoes was extracted from the pericle of the tomato and the wall material was sequentially extracted with cyclohexane-trans-1,2-diaminetetra-acetate (CDTA) at 20", 0.05 M Na,CO, at lo, 0.5, 1 and 4 M KOH at 20" to leave the cc-cellulose residue, which contained a significant amount of pectic material.

TL;DR: The essential oil content and composition of hydroponically-grown peppermint (Mentha x piperita L.) plants (29 and 36-day-old cuttings) were each affected by growth solution potential (ψ s ) and duration of exposure to mild and moderate osmotic stress as mentioned in this paper.

TL;DR: The results of this investigation indicate that there exists in C. maculatus physiological/biochemical systems vulnerable to selected plant lectins.

TL;DR: Ethological field tests indicated chemical mimesis in certain pollinator systems and chemical similarities were found between the volatiles released from Ophrys flowers and the insect glands in a number of pollination systems.

TL;DR: O-[5-O-((E)-p-coumaroyl)-α- l -arabinofuranosyl]-(1→3)-O-β- d -Xylopyranosyl-(1-4)- d -xylopyreanose (PAXX) and O-[5 O-(E)-feruloyl]-α- L -arinnosyl]--( 1→3]-O- β- D -Xynopyranose(1→4)-d -xynose (FAXX

TL;DR: The 1 H NOE difference spectra recorded for phillygenin and epipinoresinol necessitate the reversal of earlier chemical shift assignments for axial and equatorial protons on C-9 of furofuran lignans having one axialand one equatorial aryl group (the epi series).

TL;DR: Results confirm that the co-occurrence of acidic phenolic hydroxyls and lipophilic residues is an important chemical feature for the expression of antifungal activity.

TL;DR: A family of novel polyhydroxy- nor -tropanes that occur in two species of the Convolvulaceae and in Atropa belladonna are described and their potential ecological significance is discussed.

TL;DR: Cell walls were isolated from the brown algae Pelvetia canaliculata, Fucus vesiculosus, Sargassum muticum (Fucales) and Laminaria digitata (Laminariales) and then submitted to sequential chemical extraction to identify fucans present in a continuous spectrum of compounds.

TL;DR: In this paper, five sesquiterpenes, germacrone-13-al, 4,5-dihydroxybisabola-2,10-diene-9-one, 4methoxy-5-hydroxy-isoprocurcumenol, zedoaronediol, and procurcumadiol were isolated along with curcumenone.

TL;DR: The structure of ficuseptine was determined from mass spectrometry and extensive one and two dimensional NMR spectroscopy and complete 1 H and 13 C NMR assignments for antofine are reported.

TL;DR: In this article, the authors assessed the antioxidant activity of lignans and flavonoids by their effects upon the rate of rat brain homogenate autoxidation, and concluded that visible luminescence is not an appropriate method for assessing the antioxidant capacities of flavonoid or additives absorbing at wavelengths close to those of emission of the excited states involved.

TL;DR: Petioles from over 1000 individual plants of the genera Datura, Scopolia and Hyoscyamus were analysed to establish the variation in the levels and patterns of tropane alkaloids which occur between plants.

TL;DR: Rubber transferase activity was assayed in suspensions of washed rubber particles (WRPs) purified from stembark tissue of Parthenium argentatum demonstrating the firm association of the enzyme with the particles.

TL;DR: Some of the brown algae from the Black Sea were found to contain PE, PG and phosphatidyl inositol as major phospholipids but no PC, and Phosphorus-containing unidentified lipids were found in certain of the species examined.

TL;DR: Headspace components from the flowers of Nicotiana otophora and apple were trapped on Tenax and identified by GC and GC-MS, showing a marked increase in aromatic compounds released from N. sylvestris inflorescences in situ at night compared to day.

TL;DR: A cell suspension culture of Vanilla planifolia has been established in MS-medium and treatment with chitosan resulted in the induction of various enzymes of phenylpropanoid metabolism, while the amount of extractable phenolics decreased due to their rapid incorporation into polymeric ligneous material.

TL;DR: DIMBOA, the main hydroxamic acid of wheat, and its decomposition product 6-methoxy-benzoxazolin-2-one, inhibited 50% root growth of wild oat, Avena fatua at concentrations of 0.7 and 0.5 mM respectively.

TL;DR: Stilbene phytoalexins may be modified in vivo by partial methylation to further enhance their bioactivity and a quantitative structure-activity relationship study found that stilbenes brown-rot bioactivity was linearly related to hydrophobicity.

TL;DR: It is believed that the reducing pathway (menthone-menthol) was developed in young leaves on condition that they are subjected to a long photoperiodic treatment and that the metabolic pathway originally induced by the daylength in the oldest leaves was not changed by the inversion of the initial photoperperiodic treatment.

TL;DR: In this paper, the antioxidant effect of seven species of marine algae on the preservation of sunflower oil was investigated by storage experiments at 75° and 60° in heptanol with or without antioxidants.

TL;DR: This is the first reported evidence of a phenolic acid covalently associated with the cell wall hemicellulose, xyloglucan.

TL;DR: The results indicate the similarity in the metabolic fates of the curcuminoid constituents to those of the arylalkanoids of zingiberaceous plants.

TL;DR: The steroidal glycoalkaloid solamargine caused significant disruption of phosphatidylcholine/cholesterol liposomes at a concentration > 50 μM whereas the normally co-occurring glycoalkeroid solasonine was ineffective at up to 150 μM and in combination, the two compounds produced a marked synergism.