PubMed Health⌕ Search

Biomedical subjects

Fanie R van Heerden

Publications and source records attributed to Fanie R van Heerden.

6 recordsLinked to original sources

Activity of a traditional South African epilepsy remedy in the GABA-benzodiazepine receptor assay.

Aqueous and ethanol extracts of six plants, Acrotome inflata, Aptosimum indivisum, Asparagus suaveolens, Barleria bolusii, Commiphora marlothii and Sesamum triphyllum, which constitute an ancient Northern Sotho remedy for epilepsy, Sehlare sa Seebana, was tested in the GABA(A)-benzodiazepine receptor binding assay. Both aqueous and ethanol extracts of Aptosimum indivisum and Asparagus suaveolens and the aqueous extract of Commiphora marlothii showed good dose-dependent activity. The ethanol extract of all six plants extracted together was more active that the aqueous extract. The results did not suggest a synergistic effect of the plant mixture.

Animals↗

Determination of atractyloside in Callilepis laureola using solid-phase extraction and liquid chromatography-atmospheric pressure ionisation mass spectrometry.

A selective analytical method based on high-performance liquid chromatography, combined with atmospheric pressure ionisation mass spectrometry, was developed for the detection of atractyloside. The analysis was performed on an Xterra Phenyl column utilising a gradient elution profile and a mobile phase consisting of 10 mM aqueous ammonium acetate buffer-methanol-acetonitrile. The calibration curve of the method (1 ng/ml-160 microg/ml) was best described by a second order polynomial function (r2 = 0.998) but displayed good linearity in the range of 100 ng/ml-1 microg/ml (r2 = 0.999). The limit of detection for the atractyloside standard was determined and found to be 100 pg/ml and the limit of quantification of atractyloside in tuber matrix was found to be 250 pg/ml. The relative standard deviation of the method was on average below 5% (n = 8). The method was successfully applied to the analysis of Callilepis laureola tubers and unknown powdered samples for the presence of atractyloside.

Atmospheric Pressure↗

Venusol from Gunnera perpensa: structural and activity studies.

From the aqueous extract of the dry rhizomes of Gunnera perpensa the minor components pyrogallol, succinic acid, lactic acid, and the trimethyl ether of ellagic acid glucoside were isolated. The major constituent was identified as Z-venusol, a phenylpropanoid glucoside. Its structure was verified by X-ray diffraction. Tests on isolated uterine smooth muscle from rats showed that the whole extract stimulated a direct contractile response and induced a state of continuous contractility of the uterus once all additives had been removed from the organ bath. By contrast, venusol did not trigger the direct contractile response but induced the state of continuous contractility once the organ bath was flushed.

Animals↗

Saponins from Cussonia bancoensis and their inhibitory effects on nitric oxide production.

Two new triterpenoid saponins (1 and 2) were isolated from the stem bark of Cussonia bancoensis together with the known stigmasterol, ursolic acid, 23-hydroxyursolic acid (3), and 3beta-hydroxylup-20(29)-en-28-oic acid. On the basis of their spectroscopic data and on chemical transformations, the structures of the new saponins have been established as 3-O-(alpha-Ll-arabinopyranosyl)-23-hydroxyursolic acid (1) and 3-O-(beta-D-glucopyranosyl)-23-hydroxyursolic acid (2). In a nitric oxide (NO)-production bioassay, compound 3 exhibited significant NO inhibitory activity, while compounds 1 and 2 were less potent than 3.

Animals↗

A prenylated xanthone from Allanblackia floribunda.

A new prenylated xanthone, named allanxanthone A, was isolated from the stem bark of Allanblackia floribunda in addition to known compounds, 1,5-dihydoxyxanthone, 1,5,6-trihydroxy-3,7-dimethoxyxanthone, stigmasterol and stigmasteryl-3-O-beta-D-glucopyranoside. The structure of the new compound was assigned as 1,3,5-trihydroxy-2-(3-methylbut-2-enyl)-4-(1,1-dimethylprop-2-enyl) xanthone, by means of spectroscopic analysis. The 13C NMR spectral data of 1,5-dihydroxyxanthone is reported here for the first time as well as the in vitro cytotoxic activity of xanthone metabolites against the KB cell line.

Cameroon↗

Antimalarial activity of plant metabolites.

This review covers the structures of compounds with antiplasmodial activity isolated from plants and is organized according to plant family. A total of 170 structures has been reviewed from 186 references found in the literature up to December 2000.

Alkaloids↗