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Biomedical subjects

Liselotte Krenn

Publications and source records attributed to Liselotte Krenn.

10 recordsLinked to original sources
PubMed2005

Comparison of the antiinflammatory effects of Drosera rotundifolia and Drosera madagascariensis in the HET-CAM assay.

The antiinflammatory effects of ethanol and aqueous extracts from Drosera rotundifolia and from Drosera madagascariensis were compared in vivo in the HET-CAM assay. Both extracts from D. rotundifolia and the ethanol extract from D. madagascariensis showed remarkable efficacy at doses of 500 microg/pellet. The inhibition of the inflammation by the extracts was stronger than that by 50 microg hydrocortisone/pellet. In contrast, there was only a very weak effect observed at a dose of 500 microg/pellet of the water extract from D. madagascariensis. The chemical analyses of the extracts showed that the effect cannot be attributed to naphthoquinones, but might be due to flavonoids. Ellagic acid obviously plays an important role in the antiangiogenic effect of the Drosera extracts.

Allantois↗
PubMed2004

Chemotaxonomic relevance of cardenolides in Urginea fugax.

In a chemotaxonomic approach the investigation of a methanolic extract of bulbs of Urginea fugax (MORIS) STEINH. resulted in the detection of several cardenolides. The structure of a novel compound, named fugaxin (1), was established as 12alpha,14beta-dihydroxy-2alpha,3beta-(tetrahydro-3',5'-dihydroxy-4'-methoxy-6'-methyl-2H-pyran-2',4'-diylbisoxy)-card-4,20-dienolide by extensive NMR spectroscopic studies including 2D-NMR techniques (COSY, HSQC, HMQC) and selective 1D experiments (NOE, TOCSY) as well as HR-ESI-MS. The chemotaxonomic relevance of the occurrence of cardenolides in the genus Urginea is discussed.

Cardenolides↗
PubMed2004

In vitro antispasmodic and anti-inflammatory effects of Drosera rotundifolia.

In investigations of the anti-inflammatory and spasmolytic effects of Drosera rotundifolia two extracts were tested in different in vitro assays. An aqueous and an ethanolic extract inhibited human neutrophil elastase, achieving IC50 values of 5 and 1 microg/mL, respectively. The very low naphthoquinone concentrations in the extracts seem not to be responsible for the effect, as the pure compounds were not effective in the test system used. Thus, flavonoids like hyperoside, quercetin and isoquercitrin, which were detected in the extracts in considerable concentrations, may contribute to the activity. These substances showed activity in the assay. Ellagic acid, detected especially in the ethanolic extract in higher amounts, was substantially less active than the flavonoids. In guinea-pig ileum the extracts led to an antispasmodic effect possibly by affecting an allosteric binding site of the muscarinic M3 receptors.

Animals↗
PubMed2004

Anthrone C-glucosides from Rheum emodi.

In a study of the anthraderivatives in roots of Rheum emodi, three new anthrone C-glucosides, named 10-hydroxycascaroside C (1), 10-hydroxycascaroside D (2) and 10R-chrysaloin 1-O-beta-D-glucopyranoside (3) were isolated besides the rare compounds cascaroside C (4), cascaroside D (5) and cassialoin (6). Additionally the investigation resulted in the isolation of an acetylated chrysophanol glucoside, 8-O-beta-D-(6'-O-acetyl)glucopyranosyl-chrysophanol (7). The structures were established by comprehensive spectroscopic investigations.

Acetylation↗
PubMed2003

Sulfemodin 8-O-beta-D-glucoside, a new sulfated anthraquinone glycoside, and antioxidant phenolic compounds from Rheum emodi.

A sulfated emodin glucoside, emodin 8-O-beta-D-glucopyranosyl-6-O-sulfate (1), was isolated from the roots of Rheum emodi in an investigation of the active constituents of this Nepalese medicinal plant, and its structure was determined by spectroscopic and chemical methods. Additionally, two rare auronols, carpusin (2) and maesopsin (3), besides other anthraquinones and phenolics, were isolated and identified. Compounds 2 and 3 showed significant antioxidant activity in the DPPH assay, while chrysophanol, physcion, and emodin and their 8-O-glucosides were found to be inactive.

Anthraquinones↗
PubMed2003

Quantification of the flavonoid glycosides in Passiflora incarnata by capillary electrophoresis.

Capillary electrophoresis has been applied for the separation and quantification of the flavonoids in Passiflorae herba. Separations were performed using 25 mM sodium borate with 20 % methanol (pH 9.5). For the quantification quercetin 3-O-arabinoside was used as internal standard. The method was applied to the determination of the flavonoid glycosides in 10 different commercial samples of the drug and showed similar flavonoid patterns, but differences concerning the single and total amounts of flavonoids. The total flavonoid contents determined with the new method correlated satisfactorily with those achieved by the spectrophotometric assay according to the European Pharmacopoeia.

Borates↗
PubMed2002

Quantification of isoflavones in red clover by high-performance liquid chromatography.

An RP-HPLC method for the determination of daidzein, genistein, formononetin and biochanin A in red clover (Trifolium pratense L.) was developed and validated. The compounds are quantified after hydrolytic extraction using an internal standard. On a base-deactivated C(18) column good separation of the analytes, also from accompanying substances, and excellent peak shape are achieved by gradient elution with aqueous sulfuric acid and acetonitrile. The method was applied to the analysis of different red clover cultivars.

Calibration↗
PubMed2002

[Passion Flower (Passiflora incarnata L.)--a reliable herbal sedative].

Extracts and fluid extracts from the aerial parts from Passiflora incarnata L. are widely used as components of herbal sedatives. Many pharmacological investigations confirm the sedative effects of Passiflorae herba. From some of the studies also anxiolytic effects can be deduced. As Passionflower is mainly used in combinations, clinical studies of the single drug are not available. Based on pharmacological data, the experiences of traditional use and the use in combinations Passiflora extracts are an important factor in the phytotherapy of tenseness, restlessness and irritability with difficulty in falling asleep.

Anxiety↗
PubMedDate not supplied

Flavonoids from Achillea nobilis L.

The detailed investigation of a methanolic extract of aerial parts of Achillea nobilis resulted in the isolation of 10 flavonoids. A new C-glycosylflavone, luteolin-6-C-apiofuranosyl-(1'''-->2'')-glucoside, was isolated besides orientin, isoorientin, vitexin, isoschaftoside, luteolin-7-O-beta-glucuronide, luteolin-4'-O-beta-glucoside and quercetin-3-O-methyl ether and two rare flavonolglycosides, quercetin-3-O-alpha-arabinosyl-(1'''-->6'')-glucoside and quercetin-3-O-methylether-7-O-beta-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 and ESI-MS.

Achillea↗