(25/70) Anti-inflammatory activity of aqueous fruit pulp extract of Hunteria umbellata K. Schum in acute and chronic inflammation.

The anti-inflammatory effect of the aqueous fruit pulp extract of Hunteria umbellata K. Schum (Apocynaceae) was evaluated using the carrageenan- and dextran-induced rat paw edema, xylene-induced ear edema and formalin-induced arthritis inflammation tests. Oral administration of the extract produced significant (p < 0.05) antiedematogenic effect with a dose of 500 mg/kg throughout the period of the experiment in the dextran induced paw edema and at the 3 h in the carrageenan model. The extract (250 and 500 mg/kg) exhibited a dose-related and significant (p < 0.01) inhibition of xylene induced ear edema and the effect was similar to that produced by dexamethasone (1 mg/kg). In the chronic inflammation (formalin induced arthritis) the extract did not show any significant anti-inflammatory activity. Oral acute toxicity assays did not show any mortality at 15 g/kg of the plant extract. The results indicate that the aqueous extract of H. umbellata possesses acute inflammatory activity which may be mediated by either inhibition or by blocking the release of prostaglandins and histamine, thus supporting the usage of the plant in traditional medicine treatment of inflammation.  (+info)

(26/70) Two new aspidosperma indole alkaloids from Yunnan Kopsia arborea.

Two new indole alkaloids, kopsiyunnanines G (1) and H (2), possessing the Aspidosperma skeleton were isolated from the aerial part of Yunnan Kopsia arborea BLUME (Apocynaceae). Their structures and stereochemistry were elucidated by means of MS and 2D NMR analyses.  (+info)

(27/70) Oppositinines A and B: new vasorelaxant beta-carboline alkaloids from Neisosperma oppositifolia.

A phytochemical study on the bark of Neisosperma oppositifolia (Apocynaceae) yielded two new beta-carboline indole alkaloids, oppositinines A (1) and B (2), together with five known alkaloids, isoreserpiline, isocarapanaubine, vobasine, 10-methoxydihydrocorynantheol-N-oxide, and ochropposinine oxindole. Structural elucidation of 1 and 2 was performed using 2D NMR methods. Oppositinines A (1) and B (2) showed potent vasorelaxant effects on the rat aorta.  (+info)

(28/70) Application of phase-trafficking methods to natural products research.


(29/70) Concise total synthesis of (+/-)-pseudotabersonine via double ring-closing metathesis strategy.


(30/70) The steroid glycoside H.g.-12 from Hoodia gordonii activates the human bitter receptor TAS2R14 and induces CCK release from HuTu-80 cells.


(31/70) Anti-ulcer & antioxidant activities of Hedranthera barteri {(Hook F.) Pichon} with possible involvement of H+, K+ ATPase inhibitory activity.

BACKGROUND & OBJECTIVE: Hedranthera barteri (HB) is used in folk medicine as a vermifuge, laxative and an anti-inflammatory agent. The aim of this study was to evaluate the anti-ulcer and antioxidant properties of the dichloromethane fraction of HB root (DMHBR). METHODS: Anti-ulcerogenic activity was assessed in cold-restraint (CRU), aspirin (ASP), alcohol (AL), pyloric ligation (PL) induced gastric ulcer models in rats and histamine-induced duodenal ulcer (HST) in guinea pigs. The effect of DMHBR (100 mg/kg) on gastric juice for free and total acidity, peptic activity and mucin secretion, using the pylorus ligated model, were evaluated. The H+, K+-ATPase activity was assayed in gastric microsomes, spectrophotometrically. The in vitro anti-oxidant assays were explored through DPPH, nitric oxide, hydroxyl radical, superoxide anion scavenging assays. RESULTS: DMHBR reduced the incidence of ulcers in CRU (63.3%), PL (58.5%), ASP (52.7%), HST (75.0%) and AL (53.87%). Also, reductions were observed in the free acidity (49.4%), total acidity (45.8%) and peptic activity (32.9%) with increase in the mucin secretion by 81.6 per cent. DMHBR (60-100 mug/ml) inhibited the H+,K+-ATPase activity with IC50 of 89.64 mug/ml compared with omeprazole (10-50 mug/ml ) with IC50 of 32.26 mug/ml. DMHBR showed antioxidant activity with IC50 values of DPPH (397.69 mug/ml), nitric oxide (475.88 mug/ml), hydroxyl radical (244.22 mug/ml) and superoxide anion radical (285.20 mug/ml). INTERPRETATION & CONCLUSION: DMHBR showed anti-ulcer activity against experimentally-induced peptic ulcer models and exhibited both cytoprotective and anti-secretory property. It exhibited a proton pump inhibition activity and its anti-ulcer properties may be partly ascribed to its antioxidant activities.  (+info)

(32/70) Antiproliferative cardenolides from Pentopetia androsaemifolia Decne. from the Madagascar rain forest.

Plant natural products have historically been very important to drug discovery and development, particularly in the anticancer field. This is illustrated by a discussion of the structures and activities of camptothecin and its analogues, paclitaxel (Taxol), the vinca alkaloids vinblastine and vincristine, and podophyllotoxin and its analogues. A description of the isolation of one new and three known cardenolides from the Madagascar plant Pentopetia androsaemifolia is then provided as an example of this approach to drug discovery. The paper concludes with a brief discussion of betulinic acid, an old compound which is being developed into an anticancer and anti-HIV agent, and ipomoeassin F, an interesting antiproliferative compound isolated from a plant collected in Suriname.  (+info)