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PubMed1998

Effect of Tribulus terrestris L. saponin mixture on some smooth muscle preparations: a preliminary study.

Tribulus terrestris L. is an annual plant which has been commonly used in folk medicine as diuretic and against colic pains, hypertension and hypercholesterolemia in Turkey. This study investigated the effects of liophilized saponin mixture of this plant on several smooth muscle preparations in vitro. The liophilized material was obtained from dried and powdered T. terrestris L. by specific extraction method for saponins. Median lethal dose (LD50) of saponin mixture on Swiss albino mice was calculated according to Litchfield-Wilcoxon method via i.p. route. LD50 and its 95% confidence limits were 813 and 739-894 mg.kg-1 respectively. Saponin mixture has caused a significant decrease on peristaltic movements of isolated sheep ureter and rabbit jejunum preparations in a dose-dependent manner (p < 0.05). However it has been observed no effect on isolated rabbit aorta and its contractile response to KCl or noradrenaline (p > 0.05). According to these results it has been suggested that T. terrestris L. or its saponin mixture may be useful on some smooth muscle spasms or colic pains.

Animals↗

PubMed2000

Proerectile pharmacological effects of Tribulus terrestris extract on the rabbit corpus cavernosum.

INTRODUCTION: The objective of the present study was to investigate the effect of oral treatment of Tribulus terrestris (TT) extract on the isolated corpus cavernosal tissue of New Zealand white (NZW) rabbits and to determine the mechanism by which protodioscin (PTN), a constituent of the TT, exerts its pharmacological effects. MATERIALS AND METHODS: Twenty-four NZW rabbits were randomly assigned to 4 experimental groups of 6 each. Group I served as control. Groups II to IV were treated with the extract at different dose levels, i.e. 2.5 mg/kg, 5 mg/kg and 10 mg/kg body weight, respectively. The TT extract was administered orally, once daily, for a period of 8 weeks. The rabbits were then sacrificed and their penile tissue isolated to evaluate the responses to both contracting and relaxing pharmacological agents and electrical field stimulation (EFS). RESULTS: PTN on its own had no effect on the isolated corpus cavernosal strips. The relaxant responses to EFS, acetylcholine and nitroglycerin in noradrenaline precontracted tissues from treated groups showed an increase in relaxation of a concentration dependent nature compared to that of the tissues from control group. However, the contractile, anti-erectile response of corpus cavernosal tissue to noradrenaline and histamine showed no significant change between the treatment and the control groups. CONCLUSIONS: The relaxant responses to acetylcholine, nitroglycerin and EFS by more than 10%, 24% and 10% respectively compared to their control values and the lack of such effect on the contractile response to noradrenaline and histamine indicate that PTN has a proerectile activity. The enhanced relaxant effect observed is probably due to increase in the release of nitric oxide from the endothelium and nitrergic nerve endings, which may account for its claims as an aphrodisiac. However, further study is needed to clarify the precise mechanism of its action.

Animals↗

PubMed2002

Biologically active steroidal glycosides from Tribulus terrestris.

The steroidal saponin constituents obtained from Tribulus terrestris were tested for their antimicrobial and cytotoxic effects. The spirostanol-based steroidal saponins 1-3 exhibited remarkable activity against fungal organisms (Candida albicans and Cryptococcus neoformans) and cancer cell lines [human malignant melanoma (SK-MEL), human oral epidermoid carcinoma (KB), human breast ductal carcinoma (BT-549), and human ovary carcinoma (SK-OV-3)], while none of the compounds possessing the furostanol framework 4-7 showed activity. The most active spirostanol glycoside, compound 3 exhibited a broad range of anticancer activity against cell lines, SK-MEL, KB, BT-549 and SK-OV-3 at IC50s of 6.0, 7.0, 6.0 and 8.2 micrograms/ml, respectively, while compounds 1 and 2 showed selective cytotoxicity against SK-MEL at 6.7 and 9.1 micrograms/ml, respectively. The minimum inhibitory concentrations (MIC) in antifungal bioassay for compounds 1-3 varied from 1.5 to 6.2 micrograms/ml, which prompted to conclude certain structural features are required for these bioactivities.

Anti-Bacterial Agents↗

PubMedDate not supplied

[Conditions for splitting protodioscine--the main glycoside from Tribulus terrestris L. by the enzymatic preparation from Aspergillus niger BKMt-33].

The conditions for splitting protodioscine--the main steroid saponine isolated from Tribulus terrestris L. by the enzymic preparation of Aspergillus niger str. BKMt-33 were investigated. The optimal conditions were found to be as follows: pH 4-5, temperature 30-37 degrees (the substrate concentration--5 mg%, concentration of the enzymic preparation--1%). Under these conditions the enzymolysis continued 24 hours. Mg+2 and K+ ions accelerated the reaction twice. As a result of the enzymic hydrolysis dioscine and trilline were obtained. This indicates beta-glucosidase and alpha-rhamnosidase activities of the enzymic complex isolated from Aspergillus niger str. BKMt-33.

Aspergillus↗

PubMed1991

[Studies on water soluble polysaccharides isolated from Tribulus terrestris L--purification and preliminary structural determination of heteropolysaccharide H].

Crude polysaccharides extracted from the stem and leaf of Tribulus terristris L after the removal of crude saponins are a mixture of heteropolysaccharides composed of Ara, Rha, Xyl, GalA, Gal, Glc and Man in molar ratios of 6.0:2.1:1:3.6:3.4:7.7:2.9. A homogeneous polysaccharide H obtained by gradation and purification contains Ara, Rha, Xyl, GalA. Gal and Glc. in molar ratios of 1.6:2.4:0.1:3.5:1.3:1. Its molecular weight was found to be 1 x 10(5). By means of pectinase and beta-D-galactosidase enzymolysis, periodate oxidation, Smith degradation, partial hydrolysis with acid, methylation, GC and GC-MS, the H contains alpha-D-GalA (1-4) and L-Rha (1-2) probably linked alternately as main chain with some L-Rha (1-2) side chains.

Drugs, Chinese Herbal↗

PubMed1991

Photosensitivity in South Africa. VI. The experimental induction of geeldikkop in sheep with crude steroidal saponins from Tribulus terrestris.

Geeldikkop was induced in sheep by the oral administration of crude steroidal saponins from Tribulus terrestris. Two of the sheep developed typical lesions of geeldikkop, including birefringent crystalloid material in bile ducts and concentric periductal lamellar fibrosis. The clinical pathological changes in these sheep were also consistent with those of geeldikkop: aspartate transaminase and gamma-glutamyl transferase activities in the sera of both were elevated, and one had bilirubinaemia. A third sheep became photosensitive without typical lesions of geeldikkop in the liver or changes in the activities of liver enzymes before euthanasia. The findings of these trials are consistent with reports from abroad that ovine hepatogenous photosensitization, caused by Agave lechuguilla and Narthecium ossifragum, can be induced with crude saponins from the respective plants.

Animals↗

PubMed1980

Photosensitivity in South Africa. II. The experimental production of the ovine hepatogenous photosensitivity disease geeldikkop (Tribulosis ovis) by the simultaneous ingestion of Tribulus terrestris plants and cultures of Pithomyces chartarum containing the mycotoxin sporidesmin.

The mycoflora of toxic pastures were surveyed during a number of outbreaks of ovine hepatogenous photosensitivity in South Africa. Pure cultures of several isolates were dosed to sheep, but only those of Pithomyces chartarum and Myrothecium verrucaria proved to be toxic. Photosensitization was induced in sheep by dosing them with cultures of a P. chartarum isolate (GA10) obtained from Tribulus terrestris plants collected during an outbreak of geeldikkop in the Karoo. Thus for the first time a mechanism whereby T. terrestris plants can contribute to the causation of ovine hepatogenous photosensitivity was demonstrated. When cultures of GA10 equivalent to approximately 0,75--4,0 mg/kg sporidesmin were dosed at Onderstepoort Veterinary Research Institute to Highveld and Karoo sheep on a diet of lucerne, facial eczema was produced. Dosing the same cultures at levels equivalent to c. 1,0 mg/kg of sporidesmin in the Karoo resulted in lesions characteristic of both facial eczema and geeldikkop. Typical hepatic lesions of geeldikkop could be elicited by dosing GA10 at levels equivalent to c. 0,25--0,7 mg/kg of sporidesmin to Karoo sheep grazing on predominantly T. terrestris pastures in the Karoo. In the latter experiment geeldikkop was induced in the sheep on T. terrestris pastures, while those receiving identical doses on veld with little T. terrestris developed facial eczema. Geeldikkop, therefore, can be brought about by the ingestion of T. terrestris plants together with toxic cultures of P. chartarum. The plant appears not only to act as a vehicle for ingestion of spores, but also to interact with sporidesmin to induce lesions typical of geeldikkop, whereas sporidesmin alone results in facial eczema. Indications are that it can enhance the ability of sporidesmin to cause photosensitivity or, possibly, vice versa. The histopathological findings of these experiments are described in detail.

Animals↗

PubMed1994

Photosensitivity in South Africa. VIII. Ovine metabolism of Tribulus terrestris saponins during experimentally induced geeldikkop.

Geeldikkop was induced in a sheep by dosing it orally with a crude extract of the steroidal saponins from Tribulus terrestris. GC-MS analysis of the sheep's ruminal contents, bile, faeces and urine for free and conjugated sapogenins, revealed the general features of the metabolic pathway by which diosgenin and yamogenin glycosides were converted into the glucuronides of epismilagenin and episarsasapogenin, the major constituents of the biliary crystals that usually form during geeldikkop. Other steroidal saponins in the T. terrestris extract, including those derived from tigogenin, neotigogenin, gitogenin and neogitogenin appear to be non-lithogenic. The implications of these findings are discussed.

Animals↗

PubMed1994

An outbreak of hepatogenous photosensitization in sheep grazing Tribulus terrestris in Argentina.

An outbreak of hepatogenous photosensitization occurred in 40% of sheep grazing Tribulus terrestris in southern Buenos Aires province. Postmortem examinations revealed diffuse jaundice and ochre discoloration of the liver. Histopathological liver lesions consisted of fibroplasia, periductular lamellar fibrosis, hyperplasia of small bile ducts and diffuse swelling of hepatocytes. A crystalloid material was observed in some bile ducts. Aspartate aminotransferase and gamma glutamyltransferase serum activities were elevated in all tested animals while serum bilirubin content was elevated only in the most severely affected sheep. These findings are consistent with reports of geeldikkop, a photosensitivity of sheep which occurs in South Africa and Australia.

Animals↗

PubMed1996

Photosensitivity in South Africa. IX. Structure elucidation of a beta-glucosidase-treated saponin from Tribulus terrestris, and the identification of saponin chemotypes of South African T. terrestris.

Saponin C, a beta-glucosidase-treated saponin isolated from ethanol-water extracts of a South African collection of Tribulus terrestris, was shown by one- and two-dimensional NMR spectroscopy to be ruscogenin 1-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-6)-acetylglucopyranoside++ +. GC-MS analysis of the hydrolysed ethanol-water (4:1) extracts of T.terrestris specimens from two of four sites, revealed high levels of ruscogenin and potentially lithogenic diosgenin saponins. Specimens from two other sites contained non-lithogenic saponins derived predominantly from tigogenin, neotigogenin, gitogenin and neo-gitogenin.

Animals↗

PubMed1951