Search results for "ACEA"
showing 10 items of 2814 documents
Über die Verbreitung von Flavonoiden bei akrokarpen Laubmoosen
1978
Summary The methanolic extract from the sporophytes of the moss Ceratodon purpureus (L.) Brid . (Ditrichaceae) contains one flavonoid. It was isolated and purified by means of paper chromatography and identified by cochromatography with authentic material and by UV-spectral data as luteolin. No glycosides of either luteolin or another flavonoid could be detected.
On the Occurrence of Caffeoyltartronic Acid and Other Phenolics in Chondrilla juncea
1993
Abstract Caffeoyltartronic acid and other eleven phenolic com pounds were identified in the MeOH extract of Chondrilla juncea: the flavonoids luteolin, luteolin-7-glucoside, luteolin-7-galactosylglucuronide and quercetin-3-galactoside; the phenolic acids protocatechuic, caffeic, chlorogenic, isochlorogenic and isoferulic and the coumarins cichoriin and aesculetin. The taxonomic im plications of these com pounds have been discussed.
High-Yield Formation of Arbutin from Hydroquinone by Cell-Suspension Cultures ofRauwolfia serpentina
1992
High-density cell-suspension cultures of Rauwolfia serpentina cultivated in a nutrition medium optimized for the production of the glucoalkaloid raucaffricine synthesize hydroquinone glycosides from continuously added hydroquinone with a total yield of 23.87 g/1 (18 g/1 of arbutin and 5.87 g/1 of a hydroquinone diglycoside) in 7 days. This arbutin production is by far the highest formation of a natural product by plant-cell-culture systems reported to date.
Effect of pHand age of culture on cellular fatty acid composition of Leuconostoc oenos
1996
Z. DRICI-CACHON, J.F. CAVIN AND C. DIVIES. 1996. This study is concerned with the fatty acid composition of three strains of Leuconostoc oenos grown at different pH. The most abundant fatty acids were C18: 1w9, C19: 0 cy(w9,10) and C16:0, followed by C16: 1w9 and C14: 0. The pH considerably modified the fatty acid distribution in Lo107 (an acidophilic strain) and Lo8413 (a moderately acidophilic strain). However, moderate changes occurred for LoATCC 23277 (a less acidophilic strain). At pH 2.9, Lo107 has a remarkably high level of C19: 0 cy-(w9,10) and C19:0 cy(w11,12). Proportions of C18: 1 and C19:0 cyclo acids varied mainly with the pH of the medium and also as a function of growth phase…
Responses to salt stress in the halophyte Plantago crassifolia (Plantaginaceae)
2004
Abstract General responses to salt stress have been investigated in the halophyte Plantago crassifolia. Seed germination was strongly inhibited by NaCl, although seed viability and germination capacity were not affected by salt pre-treatments. A concentration-dependent inhibition of plant growth was observed in the presence of NaCl, which was accompanied by the accumulation of Na+ ions in the leaves, as determined by cation exchange HPLC. A 20-fold increase of proline content in leaves was observed when plants were treated with 500 m m NaCl, suggesting a protective role against high salinity stress for this amino acid, whose possible mechanism of action is discussed.
Xyloglucan-derived oligosaccharides induce ethylene synthesis in persimmon (Diospyros kaki L.) fruit
1998
In this work the effect of injection of xyloglucan-derived oligosaccharides (XGOs) into whole persimmon (Diospyros kaki L.) fruits on ethylene biosynthesis was investigated. Fruits collected during different ripening stages produced low levels of ethylene without a climacteric-like peak. Pretreatment of these fruits with 10 cm 3 C 2 H4 m -3 for 8 h stimulated little or no endogenous ethylene production. However, when persimmon fruits were injected with a mixture of XGOs a burst in ethylene production was observed compared with water-injected control fruits or fruits injected with different monosaccharide solutions. In order to study the influence of oligosaccharide structure and fruit ripen…
Isolation of Alkaloids from Cultured Hybrid Cells of Rauwolfia serpentina*Rhazya stricta.
1996
Two monoterpenoid indole alkaloids and four β-carbolines were isolated from a hydrid cell suspension culture generated from two Apocynaceous plants, Rauwolfia serpentina Benth. and Rhazya stricta Decaisne. This indicates that the function of alkoloid biosynthesis is retained after hybrid formation and that alkaloids not previously detected in the parental plants or cell cultures are formed.
Effects of solvent-free microwave extraction on the chemical composition of essential oil of Calamintha nepeta (L.) Savi compared with the convention…
2008
The essential oil of Calamintha nepeta has been obtained by solvent-free microwave extraction (SFME) and by classical hydrodistillation (HD). A comparative qualitative-quantitative study on the composition of the oils was carried out. A total of 38 compounds, constituting 97.6% of the oil, were identified in the oil obtained by SFME, whereas 46 compounds, representing 95.4% of the oil, were characterized in the HD oil. SFME-distilled oil is richer in lightly oxygenated monoterpenes (LOM) than HD oil. It also has a higher amount of sesquiterpenes and a lower quantity of hydrocarbon monoterpenes. HD oil seems to be affected by chemical changes more than SFME oil.
Stereoselective Synthesis of (+)-Boronolide
2002
The delta-lactone boronolide (+)-1, a pharmacologically active, naturally occurring product, has been synthesized in enantiopure form with L-erythrulose as the chiral starting material. The key steps of the synthesis were a highly stereoselective aldol-reduction one-pot sequence, an indium-mediated diastereoselective aldehyde allylation, and a ring-closing metathesis.
Flavonoids from Teucrium fruticans L.
2014
From aerial parts of <em>Teucrium fncticans</em> L. three flavonoids were isolated and identified as 5-hydroxy-6, 7, 3', 4'-tetramethoxyflavone, 5, 4'-dihydroxy-6, 7, 3'-trimethoxyflavone (cirsilineol) and 5, 4'-dihydroxy-6, 7-dimethoxyflavone (cirsimaritin). The former compound was found to be a predominant flavone aglycone constituent of the plant material. This is the first report on the isolation of flavonoids from the plant.