Two New Furostanol Saponins from Tribulus Terrestris L.

Two new furostanol glucosides, named tribufurosides G and H, were isolated from Tribulus terrestris L. The structures of the two new furostanol glucosides were elucidated as 26-O-β-D-glucopyranosyl-（25R）-5α-furost12-one-3β,22α,26-tetraol-3-O-β-D-glucopyranosyl-（ 1→2 ）-β-D-glucopyranosyl-（ 1→4 ）-β-D-galactopyranoside（ 1 ） and 26-O-β-D-glucopyranosyl-（25S）-5 α- 12-one-2 α,3,8,22 α,26-tetraol-3 -O-β-D-glucopyranosyl-（ 1 → 2 ）-β-D-glucopyranosyl-（1→4）-β-D-galactopyranoside（2） by 1 D, 2D NMR techniques, ESI-MS analysis as well as chemical methods.

Two new furostanol saponins from Tribulus terrestris L.

Two new furostanol glycoside,26-O-β-D-glucopyranosyl-(25S)-5α-furost-3β,22α,26-triol-3-O-β-D-rhamnopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→4)]-β-D-galactopyranoside(1) and 26-O-β-D-glucopyranosyl-(25S)-5α-furost-20(22)-en-2α,3β,26-triol-3-O-β-D-glucopyranosyl-(1→2)-O-β-D-glucopyranosyl-(1→4)-β-D-galactopyranoside(2) were isolated fromthe fruits of Tribulus terrestris L.The structures of two new furostanol saponins were elucidated by spectroscopic methods.

Steroidal saponins with anti-inflammatory activity from Tribulus terrestris L.

Objective:Tribulus terrestris L.(T.terrestris)is a highly valuable traditional Chinese medicine used to treat stroke,inflammation,pulmonary fibrosis,liver cancer,and urolithiasis.To identify the basic substance responsible for the anti-inflammatory effect of TST(total saponins of Tribulus),its chemical composition was systematically studied,and its effect of inhibiting nitric oxide generation and the expression of related inflammatory factors were determined.Methods:To separate chemical constituents from T.terrestris by column chromatography.Spectroscopic methods,including 1D and 2D nuclear magnetic resonance spectroscopy(NMR)and mass spectrometry(MS)techniques,were used to elucidate the isolated compounds.The anti-inflammatory activities of TST and several compounds were evaluated in vitro.Results:Fifteen steroidal saponins,including 9 furostanol steroidal saponins(1,2,3,4,5,6,7,8,and 15)and 6 isospirostanol steroidal saponins(9,10,11,12,13,and 14),were isolated from T.terrestris.TST significantly decreased the expression of tumor necrosis factor-a(TNF-a)and interleukin-6(IL-6)in RAW 264.7 cells stimulated by lipopolysaccharides.Compounds 13 and 15 evidently reduced TNF-a expression.Compounds 6,10,12,13,and 15 markedly reduced IL-6 expression.Conclusions:Compounds 1 was a novel furostanol steroidal saponin,named 26-O-b-D-glucopyranosyl-(25R)-5afurostan-12-carbonyl-20(22)-en-3b,26-diol-3-O-{b-D-xylopyranosyl-(1→2)-[b-D-xylopyranosyl-(1→3)]-b-D-glucopyranosyl-(1→4)-[a-L-rhamnopyranosyl-(1→2)]-b-D-galactopyranoside}.Compounds 2 was isolated from the family Zygophyllaceae for the first time,and 5 and 6 were isolated from the Tribulus genus.TST and compounds 6,10,12,13,and 15 exerts antiinflammatory activity.

Synergistic Hepatoprotective Effect of Feronia fimonia L,, Citrullus colocynthis L,, and Tribulus terrestris L, against Paracetamol Induced Hepatotoxicity in Swiss Albino Rats

Paracetamol toxicity induced a significant rise in AST （aspartate transaminase）, ALT （alanine transaminase）, ALP （alkhaline phisphatase）, total bilirubin, total cholesterol, Triglycerides. Administration of 150 mg/kg b.w of synergistic ethanolic extracts of Feronia limonia L., Citrullus colocynthis L., and Tribulus terrestris L. effectively reduced these pathological damages caused by paracetamol intoxication. In addition to serum parameters treatment of 150 rng/kg b.w of synergistic ethanolic extract of Feronia limonia L., Citrullus colocynthis L. and Tribulus terrestris L. also promote the body weight in albino rats. Histopathological changes of the liver samples were compared with the normal control. From our results, we may infer that the mode of action of synergistic 90% ethanolic extracts of Feronia limonia L., Citrullus colocynthis L., and Tribulus terrestris L. （150 mg/kg b.w） in affording the in vivo hepatoprotective activity against paracetamol may be due to the cell membrane stabilization, hepatic cell regeneration and activation of antioxidative enzymes such as glutathione reductase, glutathione peroxidase, superoxide dismutase and catalase.

An Acidic Polysaccharide from Tribulus terrestris

An aqueous acidic polysaccharide, named rhamnogalacturonan (designated as TTP-D2) was isolated from Tribulus terrestris L by means of DEAE-cellulose chromatography and gel filtration. The molecular mass of TTP-D2 was estimated to be 26 KDa by gel filtration. TTP-D2 is composed of galacturonic acid, rhamnose, arabinose, galactose, fucose, mannose, xylose and glucose in a ratio of 71.4 : 13.5 : 5.6 : 4.9 : 3.1 : 1.9 : 1.9 : 1.0. The main chain structure of TTP-D2 was elucidated as an acidic hetero-polysaccharide with the connection of a-(1-4) galacturonic acid with a-(1-3) rhamnose by GC analysis of partially hydrolyzed products and the determination of 1H, 13C-NMR spectra.