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1.
The crude extract of Raphanus sativus leaves (Rl.Cr) showed a dose-dependent (0.03-5.0 mg/ml) spasmogenicity in guinea-pig ileum and colon. The effect was insensitive to atropine pre-treatment but was completely abolished by pyrilamine indicating involvement of histaminergic (H(1)) receptors. The contractile effect at high doses (3.0-5.0mg/ml) was followed by relaxation. Rl.Cr also enhanced the transit of charcoal meal in mice at 30-100 mg/kg. The petroleum spirit, chloroform and aqueous fractions all showed histaminergic activity in ileum; aqueous fraction being more potent. The study shows the presence of a histaminergic component(s) along with a weak spasmolytic factor thus providing sound mechanistic basis for the traditional use of the plant in constipation.  相似文献
2.
Nematicidal constituents of the aerial parts of Lantana camara   总被引:5,自引:0,他引:5  
Two new constituents, lantanoside (1) and lantanone (2), and the known compounds linaroside (3) and camarinic acid (4) were isolated from the aerial parts of Lantana camara. Compounds 1, 3, and 4 were tested for nematicidal activity against root-knot nematode Meloidogyne incognita and showed 90, 85, and 100% mortality, respectively, at 1.0% concentration. The results were comparable to those obtained with the conventional nematicide furadan (100% mortality at 1.0% concentration). Structures of the new compounds were elucidated by spectroscopic and chemical techniques.  相似文献
3.
Four new flavones and a new isoflavone from Iris bungei   总被引:5,自引:0,他引:5  
Four new irisflavones A-D (1-4) and irilin D (5) have been isolated from the underground parts of Iris bungei along with known isoflavones, irilins A-B (6-7) and tlatancuayin (8). The structures of the new compounds were determined using NMR and mass spectroscopic methods and were found to be 2',5,7-trihydroxy-3,6-dimethoxyflavone (1), 2',5-dihydroxy-3,6,7-trimethoxyflavone (2), 2',5,6'-trihydroxy-3,6,7-trimethoxyflavone (3), 3,3',5-trihydroxy-2',7-dimethoxyflavone (4), and 3',4',5,7-tetrahydroxy-6-methoxyisoflavone (5). The structures of irisflavones 1, 3, and 4 were confirmed by single-crystal X-ray diffraction studies.  相似文献
4.
Some species of marine benthic algae belonging to the Chlorophyta, Phaeophyta and Rhodophyta collected from different coastal areas of Karachi (Pakistan) were investigated for their antibacterial, antifungal, phytotoxic and insecticidal activities. Brown seaweeds showed greater antibacterial activity than the green and red ones. Botryocladia leptopoda (J. Ag.) Kylin exhibited the greatest antifungal activity and Codium shameelii Nizam. the least. The highest phytotoxic activity (95%) was displayed by Enteromorpha intestinalis (L.) Nees at 100 microg/mL concentration, while Osmundea pinnatifida (Huds.) Stack. showed the low insecticidal activity as compared to the other investigated species. Many elements e.g. Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Na, Pb, Zn were determined quantitatively. Among them Ca, Cr and Pb were found to occur in largest amount in green seaweeds, Co, Cu, Fe and Zn in greatest quantity in brown seaweeds, while Cd, K, Mg and Na in highest proportion in the investigated red seaweeds.  相似文献
5.
Quinolizidine alkaloids from Sophora alopecuroides   总被引:4,自引:0,他引:4  
A new matrine-type alkaloid, 7alpha-hydroxysophoramine (1), was isolated from the aerial parts of Sophora alopecuroides together with eight known alkaloids, 12beta-hydroxysophocarpine (2), sophoramine (3), 14beta-hydroxymatrine, matrine, sophoridine, sophocarpine, adenocarpine, and baptifoline. The structures of compounds 1-3 were confirmed through single-crystal X-ray diffraction analysis.  相似文献
6.
Anti-inflammatory isoflavonoids from the rhizomes of Iris germanica   总被引:3,自引:0,他引:3  
The anti-inflammatory activity of nine isoflavonoids 5,7-dihydroxy-3-(3'-hydroxy-4',5'dimethoxy)-8-methoxy-4H-1-benzopyran-4-one 1, 5,7-dihydroxy-3-(3'-hydroxyl-4', 5'-dimethoxy)-6-methoxy-4H-1-benzopyran-4-one 2, 5, 7-dihydroxy-3-(4'-hydroxy)-6-methoxy-4H-1-benzopyrane-4-one 3, 5-hydroxy-3-(4'-hydroxy)-6,7-methylenedioxy-4H-1-benzopyran-4-one 4, 5-hydroxy-3-(4'-methoxy)-6,7-methylenedioxy-4H-1-benzopyran-4-one 5, 5-methoxy-3-(4'-hydroxy)-6,7-methyenedioxy-4H-1-benzopyran-4-one 6, 5,7-dihydroxy-3-(3'-hydroxy-4'-methoxy)-6-methoxy-4H-1-benzopyran-4-one 7, 5,7-dihydroxy-3-(3'-methoxy-4'-hydroxy)-6-methoxy-4H-1-benzopyran-4-one 8, and isopeonol 9 determined by a spectrophotometric assay using the activated human neutrophils. These isoflavonoids were isolated from an important folkloric medicinal plant Irsa (Iris germanica L.), a member of the family Iridaceae. Structures of these compounds were identified by spectral comparison with the reported data and active members of this group adds into the growing number of non-steroidal anti-inflammatory agents.  相似文献
7.
New norditerpenoid alkaloids from Aconitum falconeri   总被引:2,自引:0,他引:2  
The roots of Aconitum falconeri have yielded two new norditerpenoid alkaloids, faleoconitine (1) and 3'-methoxyacoforestinine (2) along with the known compounds, karakoline, 3-hydroxy-2-methyl-4H-pyran-4-one, and 3,4-dimethoxymethylbenzoate, which have been isolated for the first time from this plant. The previously reported pseudaconitine (3) was also isolated. Compounds 1 and 3 were found to be moderate inhibitors of the enzyme acetylcholinesterase.  相似文献
8.
Antiulcerogenic activities of three plant drugs were studied against aspirin-induced gastric ulcers in rats. In addition, their effects on output of gastric acid and pepsin and hexosamine concentrations in gastric fluid were recorded in ulcerated and non-ulcerated rats. Solanum nigrum (aerial parts) powder and its methanolic extract decreased the ulcer index significantly. The activity may be due to inhibition of acid and pepsin secretions and/or their in vitro ability to bind these. Brassica oleracea (leaf) powder did not affect the ulcer index significantly but its aqueous extract lowered the index and increased hexosamine levels, suggesting gastric mucosal protection. Ocimum basilicum (aerial parts) powder and its aqueous and methanolic extracts decreased the index. Moreover, the acid output was decreased by its methanolic extract while hexosamine secretion was enhanced. This suggests that its antiulcerogenic effect is due to decreases of acid and pepsin outputs which enhance gastric mucosal strength. The reference drug gefarnate decreased the ulcer index by increasing the hexosamine level only. Cimetidine inhibited the acid production but did not decrease the ulcer index.  相似文献
9.
Four fractions from the leaves of Indigofera oblongifolia were obtained on Sephadex G-25 column chromatography. A single bands of these fractions were detected on Poly-acrylamide SDS gel electrophoresis. An antibacterial action of small protein peptide was tested against Escherichia coli, Klebsiella aerogenes, Kl. pneumoniae. Staphyllococcus aureus, and Bacillus subtilis. Peptide 3 showed strong inhibitory activity against B. subtilis and Aspergillus niger but clear zone of inhibition was also noted against A. fumigatus. Peptide 4 showed significant inhibitory zone against Kl. pneumoniae, S. aureus, B. subtilis. A. fumigatus, A. niger and A. flavus.  相似文献
10.
The present study demonstrates the calcium antagonistic activity in ethanol extract of Bacopa monniera. The plant extract inhibited the spontaneous movements of both guinea-pig ileum (IC50 = 24+/-4 microg/ml) and rabbit jejunum (IC50 = 136+/-9 microg/ml). A marked reduction in acetylcholine- and histamine-induced responses (0.0001-10 microM) in the ileum was evident in the presence of extract (260 microg/ml). The acetylcholine (1 microM)-induced contraction in the ileum was also inhibited by the extract (100-700 microg/ml) in a concentration dependent way (IC50 = 285+/-56 microg/ml). All these results indicate a direct action of the extract on smooth muscles. Calcium chloride-induced responses in the rabbit blood vessels and jejunum were attenuated in the presence of plant extract (10-700 microg/ml) implying a direct interference of plant extract with influx of calcium ions in the cells. However, the lack of modification of either noradrenaline- or caffeine-induced contractions in the presence of extract suggests that extract has no detectable effect on mobilization of intracellular calcium. These results indicate that spasmolytic effect of the B. monniera extract in smooth muscles is predominantly due to inhibition of calcium influx via both voltage and receptor operated calcium channels of the cell membrane.  相似文献
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