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1.
The effect of aqueous and alcohol extracts of the fruits and leaves of Pongamia pinnata (Linn.) Merr. (Syn. Pongamia glabra Vent, leguminosae) on the spontaneous movements of both the whole worm and the nerve-muscle preparation of Setaria cervi and on the survival of micro fi lariae in vitro was studied. The aqueous and alcohol extracts of fruits and the alcohol extract of leaves caused an inhibition of spontaneous movements of the whole worm and the nerve-muscle preparation of S. cervi. The initial stimulatory effect was not observed with the aqueous extract of fruits on the nerve-muscle preparation. The concentration required to inhibit the movements of the whole worm preparation was 250 micro g/mL for aqueous, 120 micro g/mL for alcohol extract of fruits and 270 microgram/mL for alcohol extracts of the leaves. The concentrations of P. pinnata extracts required to produce an equivalent effect on the nerve-muscle preparation were 25 micro g/mL, 5 micro g/mL and 20 micro g/mL, respectively, suggesting a cuticular permeability barrier.  相似文献   

2.
The effect of aqueous and alcohol extracts of the leaves and seeds of Psoralea corylifolia, on the spontaneous movements of both the whole worm and the nerve muscle preparation of Setaria cervi and on the survival of microfilariae in vitro was studied. Alcohol extracts of both leaves and seeds caused the inhibition of spontaneous movements of the whole worm and the nerve muscle preparation of S. cervi, characterised by initial, short lasting small increase in tone of contractions followed by paralysis. The initial stimulatory effect was not observed by alcohol extract of leaves on nerve muscle preparation. The concentrations required to inhibit the movements of whole worm and nerve muscle preparations for alcohol extracts of leaves and seeds were 160, 30, and 150, 20 microg/ml, respectively suggesting a cuticular permeability barrier. Alcohol extracts of both leaves and seeds caused death of microfilariae in vitro, LC(50) and LC(90) being 15 and 25 ng/ml for alcohol extract of leaves and 12 and 18 ng/ml for alcohol extract of seeds, respectively.  相似文献   

3.
The effect of aqueous and alcohol extracts of the roots of Saxifraga stracheyi Engl. On the spontaneous movements of both the whole worm and the nerve muscle preparation of Setaria cervi and on the survival of microfilariae in vitro was studied. Both extracts caused the inhibition of spontaneous movements of the whole worm and the nerve-muscle preparation of S. cervi, characterized by an increase in the amplitude and a decrease in the rate of contractions, while the tone of the contractions remained visibly unaffected. The concentration required to inhibit the movements of the whole worm preparation was 140 microg/ml for the aqueous and 250 microg/ml for the alcohol extract. The concentration of S. stracheyi extracts required to produce an equivalent effect on the nerve-muscle preparation was 30 microg/ml for aqueous, and 20 microg/ml for the alcohol extract, suggesting a cuticular permeability barrier.  相似文献   

4.
The leaves of Hancornia speciosa Gomes (Apocynaceae), a medicinal species found in the Brazilian cerrado biome, are traditionally used to treat wounds and inflammatory disorders. The goal of the present study was to investigate the in vitro wound healing properties of ethanolic extract of H. speciosa leaves and its isolated compounds, using the scratch assay, and to evaluate their effects on the release of the pro‐inflammatory cytokine tumor necrosis factor (TNF‐α) by lipopolysaccharide (LPS)‐stimulated human acute monocytic (THP‐1) cells. H. speciosa ethanolic extract significantly increased (42.8% ± 5.4 at 25 µg/mL) cell migration and proliferation of fibroblasts compared with control cells, as well as the isolated compounds bornesitol (80.8% ± 5.1) and quinic acid (69.1% ± 6.2), both assayed at 50 μM. TNF‐α release by LPS‐stimulated THP‐1 cells was significantly reduced by the ethanolic extract (62.9% ± 8.2, i.e. 1791.1 ± 394.7 pg/mL) at 10 µg/mL, bornesitol (48.9% ± 0.9, i.e. 2461.6 ± 43.1 pg/mL) at 50 μM, and quinic acid (90.2% ± 3.4, i.e. 473.5 ± 164.4 pg/mL) and rutin (82.4% ± 5.6, i.e. 847.0 ± 271.8 pg/mL) at 10 μM. These results provided evidences to support the traditional use of H. speciosa leaves to treat wounds and inflammatory disorders. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

5.
The presence of different extracts of antiinflammatory plants Copaifera reticulata and Heisteria pallida in a reaction medium containing calf thymus DNA in a free radical generating system protected DNA against oxidative damage in terms of deoxyribose oxidation. The highest antioxidant activity was obtained using the methanol extract of C. reticulata (IC50=3 μg/mL), followed by the aqueous extracts of H. pallida (IC50=257 μg/mL) and C. reticulata (IC50=380 μg/mL). Both dichloromethane extracts and the methanol extract of H. pallida showed a decreased antioxidant activity at higher concentrations. These results suggest that these extracts are capable of suppressing the in vitro oxidative degradation of DNA. © 1997 John Wiley & Sons, Ltd.  相似文献   

6.
Chilean flora is a potential source of bioactive compounds, including some with antiviral activity. Ninety aqueous and hydroaloholic extracts from 36 native and introduced plant species were screened for antiviral activity on herpes (HSV-1 and HSV-2) and HIV viruses. Furthermore, the samples were assayed for antimicrobial effect on pathogenic bacteria and a yeast. Plants were selected according to their indication of use for treating symptomatology of possible viral aetiology in Chilean folk medicine. The hydroaloholic extracts of Cassia stipulacea and Escallonia illintia exhibited detectable antiviral effects towards HSV-1 with IC50 values of 80 and 40 μg crude extract/mL, respectively. Samples belonging to Aristotelia chilensis (IC50 of 40 μg/mL), Drymis winteri (IC50 values of 35 and 80μg/mL), Elytropus chilensis and Luma apiculata, with an IC50 value of 100 μg/mL showed activity against HSV-2. None of the extracts showed activity against HIV at extract concentrations which were nontoxic for cells.  相似文献   

7.
An aqueous fraction of the ethanol extract of the leaves (AFL) of Cissampelos sympodialis Eichl. (Menispermaceae) was shown to relax the spontaneous tone of guinea-pig tracheal smooth muscle rings with an IC50 of 20.5 μg/mL. The AFL inhibited cyclic nucleotide phosphodiesterase activity in isolated smooth muscle homogenates and stimulated an increase in intracellular cAMP synthesis in intact cultured smooth muscle cells. A complete inhibition of phosphodiesterase activity in isolated homogenates was almost achieved. These studies indicate that the AFL contains a substance which is a non-selective, but highly potent inhibitor of phosphodiesterase activity. This probably accounts for its effect on the spontaneous tone of guinea-pig tracheal smooth muscle. © 1997 John Wiley & Sons, Ltd.  相似文献   

8.
A series of 15 Rwandese medicinal plants used by traditional healers to treat pulmonary diseases were screened for anti-Mycobacterium tuberculosis activity. Three plant extracts showed activity at 1000 μg/mL: Bidens pilosa (leaves), Pentas longiflora (roots) and Tetradenia riparia (leaves). These plant extracts were studied further against several mycobacterial species: M. tuberculosis, M. avium complex, M. simiae and a new simiae like Mycobacterium species (SLM). None of the plant extracts showed activity against M. avium and SLM at 1000 μg/mL. M. simiae was sensitive to T. riparia and P. longiflora extracts (1000 μg/mL) and M. tuberculosis towards T. riparia (500 μg/mL) and B. pilosa (100 μg/mL). The active principle of T. riparia, 8(14), 15-sandaracopimaradiene-7α, 18-diol, was also evaluated for its antimycobacterial activity and the concentration required for inhibiting M. tuberculosis ranged from 25 μg/mL to 100 μg/mL. The extract of the leaves of T. riparia can be used as a differentiation test (at 1000 μg/mL in the medium) for M. simiae and SLM.  相似文献   

9.
The methanol extract of Striga senegalensis Benth (Scrophulariaceae) was investigated on isolated rat uterus. Acetylcholine and the methanol extract of the plant produced dose related contractions of smooth muscle of the isolated rat uterus in vitro. Atropine in doses of 2 × 10−2 to 32 × 10−2 μg/mL antagonized dose dependently the contraction of the isolated rat uterus produced by both acetylcholine (1.6 × 10−1 μg/mL) and the methanol extract (160 μg/mL). © 1998 John Wiley & Sons, Ltd.  相似文献   

10.
The aqueous fraction of the ethanol extract of the root of Cissampelos sympodialis, reduced the spontaneous tone, and inhibited the contractions induced by submaximal concentrations of carbachol, histamine, prostaglandin F and substance P, in guinea-pig tracheal preparations. The fraction was approximately equipotent to aminophyl-line and the IC50 values of the above agents varied from 13.9 to 95.5 μg/mL, depending on the agonist used. In concentrations ranging from 1–100 μg/mL, the fraction also increased the intracellular levels of cyclic adenosine monophosphate in guinea-pig bronchoalveolar leucocytes. It is proposed that the combined effects on smooth muscles and on leucocytes indicate a pharmacological basis for the use of the plant in asthma.  相似文献   

11.
Withania somnifera is commonly used as a rejuvenator, whereas Centella asiatica is well known for its anxiolytic and nootropic effects. The present study aims at investigating the effect of crude extracts and principal phytoconstituents of both the medicinal plants with CYP3A4 and CYP2D6 enzyme activity in human liver microsomes (HLM). Phytoconstituents were quantified in the crude extracts of both the medicinal plants using reverse phase HPLC. Crude extracts and phytoconstituents of W. somnifera showed no significant interaction with both CYP3A4 and CYP2D6 enzymes in HLM. Of the crude extracts of C. asiatica screened in vitro, methanolic extract showed potent noncompetitive inhibition of only CYP3A4 enzyme (Ki—64.36 ± 1.82 µg/mL), whereas ethanol solution extract showed potent noncompetitive inhibition of only CYP2D6 enzyme (Ki—36.3 ± 0.44 µg/mL). The flavonoids, quercetin, and kaempferol showed potent (IC50 values less than 100 μM) inhibition of CYP3A4 activity, whereas quercetin alone showed potent inhibition of CYP2D6 activity in HLM. Because methanolic extract of C. asiatica showed a relatively high percentage content of quercetin and kaempferol than ethanol solution extract, the inhibitory effect of methanolic extract on CYP3A4 enzyme activity could be attributed to the flavonoids. Thus, co‐administration of the alcoholic extracts of C. asiatica with drugs that are substrates of CYP3A4 and CYP2D6 enzymes may lead to undesirable herb‐drug interactions in humans. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

12.
231 Ethanol/aqueous extracts from New Zealand plants were screened for inhibitory activity against HIV-1 protease using fluorogenic and HPLC assays. Among the examined extracts, Pseudotsuga menziesii , Elaeocarpus hookerianus , Pernettya macrostigma and Cassinia leptophylla showed significant inhibition at a concentration of 50 μg/mL in the HPLC confirmation assay. The IC50 values of these extracts to HIV-1 protease on its synthetic peptide substrate were 9.63, 9.74, 27.62 and 60.73 μg/mL, respectively. The derivatives of dihydroquercetin and [5′5′]-bisdihydroquercetin from Pseudotsuga menziesii could be the causative compounds for the inhibition.  相似文献   

13.
To find new herbal compounds with an acetylcholinesterase (AChE) inhibitory effect, this study focused on herbal drugs and resins which have been used in Iranian traditional medicine for the treatment of cognitive disorders. Forty drugs were selected from authoritative written documents of Iranian traditional medicine. Each drug was extracted by accelerated solvent extraction using dichloromethane followed by methanol. The 80 extracts were screened for AChE inhibitory activity by a TLC bioautography method. The inhibiting effect of the 32 most active extracts was measured by a microplate colorimetric assay. Due to the best activity, the seeds of Peganum harmala L. were investigated in detail. From the TLC bioautography assay the alkaloids harmaline and harmine were identified as active compounds. This result was confirmed by means of HPLC‐DAD. The IC50 values were 41.2 μg/mL for the methanol extract, 95.5 μg/mL for the dichloromethane extract, 8.4 μg/mL for harmaline and 10.9 μg/mL for harmine. The concentrations of active compounds in the extracts were determined by a fast and precise HPLC method. As the amounts of harmaline and harmine in the extracts were correlated with the IC50 values of the extracts, it can be concluded that these two alkaloids are responsible for the AChE inhibitory activity of P. harmala. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

14.
The antioxidant activity of organic extracts of eight fungal species, Ganoderma lucidum, Ganoderma applanatum, Meripilus giganteus, Laetiporus sulphureus, Flammulina velutipes, Coriolus versicolor, Pleurotus ostreatus and Panus tigrinus, was evaluated for free radical (DPPH· and OH·) scavenging capacity and an effect on lipid peroxidation, and the antibacterial activity was tested by the agar well diffusion method. The highest DPPH· scavenging activity was found in the methanol extract of G. applanatum (12.5 μg/mL, 82.80%) and the chloroform extract of G. lucidum (510.2 μg/mL, 69.12%). The same extracts also showed the highest LP inhibition (91.83%, 85.09%) at 500 μg/mL, while the methanol extracts of G. applanatum and L. sulphureus showed the highest scavenging effect on OH· radicals (68.47%, 57.06%, respectively) at 400 μg/mL. A strong antibacterial activity against Gram‐positive bacteria was also manifested. The antioxidative potencies correlated generally with the total phenol content (0.19–9.98 mg/g). The HPLC determination showed that the majority of analysed species contained gallic and protocatechic acids. Consequently, these fungi are shown to be potential sources of antioxidative and antibacterial agents. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

15.
The anti-human immunodeficiency virus type-1 (HIV-1) activity of two South American plant extracts was studied in vitro. The concentrations of aqueous extracts of Achyrocline flaccida Wein DC (AF) and Gamochaeta simplicicaulis (GS) that inhibit 50% of viral production were 3 and 5 μg/mL respectively. The concentrations that inhibit cellular growth were 400 and 600 μg/mL. Non-virucidal activity was detected. The results indicate that the potent anti-HIV-1 activities of both AF and GS extracts might occur at an early step of viral replication on infected lymphocytes of primary origin. © 1997 John Wiley & Sons, Ltd.  相似文献   

16.
The present study evaluated the radical scavenging and angiotensin converting enzyme (ACE) inhibitory activity of cold and hot aqueous extracts of Ficus racemosa (Moraceae) stem bark. The extracts were standardized using HPLC. Radical scavenging activity was determined using 1,1‐diphenyl‐2‐picrylhydrazyl radical and angiotensin converting enzyme inhibitory activity using rabbit lung and partially purified porcine kidney ACE. HPLC profiles of cold aqueous extract (FRC) showed the presence of bergenin, an isocoumarin, while hot aqueous extract (FRH) was found to contain ferulic acid, kaempferol and coumarin in addition to bergenin. FRH showed significantly higher (p ≤ 0.01) radical scavenging activity than FRC and butylated hydroxytoluene (BHT), consequently resulting in a significantly lower (p ≤ 0.01) IC50 value than FRC and BHT. Both the extracts exhibited a dose dependent inhibition of porcine kidney and rabbit lung ACE. FRH showed significantly higher (p ≤ 0.01) activity than FRC with lower IC50 values of 1.36 and 1.91 μg/mL respectively, for porcine kidney and rabbit lung ACE, compared with those of FRC (128 and 291 μg/mL). Further, a significant correlation (r = 0.893; p ≤ 0.05) was observed between radical scavenging activity and ACE‐inhibitory activity. This is the first report on the ACE‐inhibitory activity of F. racemosa stem bark suggesting its potential to be utilized as a therapeutic alternative for hypertension. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

17.
The in vitro activity of the methanol extracts of 51 plants randomly collected from the Kingdom of Saudi Arabia and some of their fractions (petroleum ether, chloroform, ethyl acetate and aqueous) were evaluated against Plasmodium falciparum, Trypanosoma brucei brucei, T. cruzi and Leishmania infantum, as well as toxicity against MRC‐5 fibroblast cells. Ten crude methanolic extracts that demonstrated potent and adequately selective antiprotozoal activity were subjected to solvent fractionation using petroleum ether, ethyl acetate and chloroform. Only three samples showed promising antiprotozoal activity. Argemone ochroleuca (CHCl3 fraction) showed pronounced activity against P. falciparumGHA (IC50 0.32 μg/mL) and T. cruzi (IC50 0.30 μg/mL) with low cytotoxicity against MRC‐5 cells (CC50 11.6 μg/mL). Capparis spinosa (EtOAc fraction) showed pronounced activity against P. falciparumGHA with an IC50 0.50 μg/mL in the absence of toxicity against MRC‐5 cell line (CC50 > 30 μg/mL). Heliotropium curassavicum (CHCl3 fraction) showed similar activity against P. falciparum (IC50 0.65 μg/mL; MRC‐5 CC50 > 30 μg /mL). These three extracts will be subjected for further extensive studies to isolate and identify their active constituents. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

18.
Portions of the hot water extract, chloroform and n-butanol fractions of the leaves of Musanga cecropioïdes were used to challenge uterine strips from nonpregnant and early stage pregnant (3–8 days) female Wistar rats. Uterine strips were obtained from oestrogenized females. The aqueous and n-butanol extracts (10 mg/L showed very marked uterotonic effects which were more pronounced in the pregnant females. These contractile effects were dose-dependent and comparable to oxytocin and acetylcholine (100 μg/mL) but were all antagonized by ethanol, a potent Ca2t channel antagonist. These effects may account for the abortifacient properties of the extracts observed in previous in vivo trials.  相似文献   

19.
Terminalia arjuna (Combretaceae) is used traditionally in ayurveda, to treat a variety of cardiovascular disorders. The aims of this study were to characterize the positive inotropic effect of the aqueous extract of T. arjuna bark in isolated paced rat left atria and to study its effects on a vascular smooth muscle preparation, the rat thoracic aorta. The crude and semipurified aqueous extracts produced a positive inotropic effect of rat atria and the maximum contraction was comparable to that produced by isoprenaline. The positive inotropic effect of the extract was completely blocked by a β-adrenoceptor blocker, propranolol, and an uptake-1 blocker, cocaine. In precontracted aorta, the aqueous extract produced a contraction followed by relaxation. Propranolol did not block the relaxant effect of the aqueous extract. It is concluded that the positive inotropic effect of the aqueous extract was mediated via an action on β1-adrenoceptors and was likely to be due to the release of noradrenaline from the sympathetic nerve endings. The vasorelaxant effect of the extract, however, was not mediated via an action on β2 adrenoceptor.  相似文献   

20.
The effects of the essential oil of the plant Croton zehntneri (EOCz) in the concentration range 1–200 μg/mL were studied on the mechanical activity of various in vitro smooth muscle preparations of the guinea-pig. In isolated ileum EOCz induced a variable response such that in 57% of tissues basal tone was reduced (EC50 5 μg/mL) whereas the rest remained unaffected by the oil. In concentrations above 10 μg/mL EOCz induced spontaneous oscillatory contractions in all preparations. In contrast the basal tone of the aorta, portal vein and bladder remained unaltered by the oil. In the portal vein EOCz concentration-dependently inhibited the amplitude of spontaneous contractions (IC50 109 μg/mL) without reducing frequency, whereas in the bladder such activity was increased by the oil (EC50 44 μg/mL). In ileum precontracted with 60 mM KCl, EOCz induced a complete and concentration-dependent relaxation with an IC50 value of approximately 26 μg/mL. In contrast EOCz did not relax KCl-induced tone in the aorta or bladder, whilst eliciting less than 20% relaxation of the precontracted portal vein. Thus our data show that EOCz exerts differential modulatory effects on the contractility of various smooth muscles of the guinea-pig. That EOCz appears to selectively relax intestinal smooth muscle may support its use in folk medicine as a gastrointestinal antispasmodic. © 1998 John Wiley & Sons, Ltd.  相似文献   

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