Search results for "pharmacognosy"
showing 10 items of 127 documents
In vitro pharmacological evaluation of the dichloromethanol extract fromSchinus molle l.
1998
The pharmacological activity of the dichloromethanol extract of Schinus molle L. (SM-DCM) was analysed in in vitro models. Preincubation of the isolated guinea-pig ileum or rat uterus preparations with the extract (100 μg/mL) abolished the contractile effects of histamine and serotonin respectively. At the same dose, the extract partially reduced the contractile effects of acetylcholine on the isolated rat duodenum. A 10 μg/mL dose showed an inhibitory effect on histamine and serotonin, but not on acetylcholine-induced contractions (NS). No significant effect was found with a 1 μg/mL dose. © 1998 John Wiley & Sons, Ltd.
Two New Eudesmanolides from Artemisia caerulescens subsp. gargantae.
1990
Effects on arterial blood pressure of the methanol extracts from differentTeucriumspecies
1997
Methanol extracts of the leaves and stems of two Teucrium species (T. pumillum L. and T. buxifolium L.) have been tested for their effects on resting arterial blood pressure. Both T. pumillum L. and T. buxifolium L. extracts reduced mean arterial blood pressure in a dose dependent manner when administered i.v. to urethane anaesthetized normotensive rats. © 1997 John Wiley & Sons, Ltd.
Neoclerodane Diterpenoids from Teucrium maghrebinum
2000
Eight neoclerodane diterpenoids were identified in the extract of the aerial parts of Teucrium maghrebinum. Three of these, 12-epi-teucjaponin A (1), 12-epi-montanin D (2), and 12-epi-montanin B (3), are new natural products, whereas five, teucjaponin A, montanin D, 19-deacetylteuscorodol, teusalvin C (4), and montanin B, are already known. These eight compounds form four pairs of epimers at carbon C-12.
Secoiridoids and Xanthones fromGentianella nitida
1996
From Gentianella nitida twelve known metabolites were isolated and identified by HPLC-UV and/or by spectroscopic methods as secologanoside, amaroswerin, amarogentin (secoiridoids), isoorientin (C-glucosylflavone), mangiferin, demethylbellidifolin 8-O-glucoside, norswertianine 1-O-glucoside, swertianine 1-O-primeveroside, swertianine 8-O-glucoside, norswertianine, demethylbellidifolin, and swertianine (xanthone glycosides and aglycones). Secologanoside is reported here for the first time in Gentianaceae species ; the antioxidant mangiferin was obtained as the major compound in good yield.
Diepoxyrollin and Diepomuricanin B: Two New Diepoxyacetogenins from Rollinia membranacea Seeds
1997
Diepoxyrollin (1) and diepomuricanin B (2), two new Annonaceous acetogenins were isolated from the cytotoxic MeOH extract of the seeds of Colombian Rollinia membranacea. Five others known acetogenins were also isolated, dieporeticanin 1, dieporeticanin 2, diepomuricanin A, rollinone, and sylvaticin. Their structures were elucidated on the basis of spectral data. Compounds 1 and 2 belong to the rare type of diepoxyacetogenins, which are probably precursors of the mono-tetrahydrofuran acetogenins.
New Diosgenin Glycosides from Costus afer
1997
Two new steroidal saponins, aferosides B (1) and C (2), together with the known saponins, dioscin (3) and paryphyllin C (4), were isolated from the roots of Costus afer. The known flavonoid glycoside, kaempferol 3-O-α-l-rhamnopyranoside (5), was obtained from the aerial parts. The structures of the new compounds were elucidated principally by 2D NMR spectral methods. A structural revision of the sugar sequence was made for the previously reported saponin aferoside A (6) on the basis of detailed spectroscopic analysis. Saponins 1−4 and 6 did not show any ability to potentiate in vitro cisplatin cytotoxicity in a human colon cancer cell line.
Neoclerodane Diterpenoids from Scutellaria polyodon
1997
Nine new neoclerodane diterpenoids, scupolins A−I, have been isolated from an Me2CO extract of the aerial parts of Scutellaria polyodon (3−11), together with the known neoclerodanes jodrellin B (1) and scutecolumnin A (2). Structures 3−11 were established by spectroscopic means and by comparison with closely related compounds.
Globularia alypumL. extracts reduced histamine and serotonin contractionin vitro
2002
The present study analyses in in vitro models the pharmacological activity of methanol and dichloromethane extracts (1, 10 and 100 microg/mL) obtained from the leaves and stems of Globularia alypum L. Preincubation of the guinea-pig ileum and rat uterus with both extracts produced a dose dependent abolition of the contractile effects of histamine and serotonin, respectively. At the same doses, neither methanol nor dichloromethane extract reduced the contractile effects of acetylcholine on rat duodenum or noradrenaline on rat vas deferens.
Cardiovascular effects of the methanol and dichloromethanol extracts fromTeucrium cartaginenses L.
1998
Methanol and dichloromethanol extracts of the leaves and stems of Teucrium cartaginensesL. have been tested for their effects on resting arterial blood pressure, heart rate and noradrenaline induced hypertension. Both extracts administered i.v. to urethane anaesthetized normotensive rats reduced mean arterial blood pressure and heart valve, while only the dichloromethanol extract prevented noradrenaline induced hypertension. © 1998 John Wiley & Sons, Ltd.