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排序方式: 共有117条查询结果,搜索用时 62 毫秒
1.
Context: Scutellaria lindbergii Rech. f. (Lamiaceae) is an Iranian species of Scutellaria which has been shown to exert antimicrobial, antioxidant and cytotoxic effects. Objective: The protective properties of total methanol extract (TME) of S. lindbergii and its fractions (defatted and CH2Cl2) were investigated against cytotoxic and genotoxic effects of H2O2 in NIH 3T3 cell line as non-malignant cells. Materials and methods: The cells were incubated with different concentrations of S. lindbergii root extracts [TME (15–250?μg ml?1), defatted fraction (15–500?μg ml?1) and CH2Cl2 fraction (5–40?μg ml?1)] and toxic concentration of H2O2 (200?µM) at 37?°C for 2?h concurrently and Cell viability was quantitated by MTT assay. The antigenotoxic effect of extracts was investigated using comet assay. The cells were incubated with extracts [TME (25–250?μg ml?1), defatted fraction (25–500?μg ml?1) and CH2Cl2 fraction (5–40?μg ml?1)] and H2O2 (25?µM) at 4?°C for 20?min, then the comet assay was performed. DNA damage was expressed as percentage tail DNA. Results: Total methanol extract of S. lindbergii and its fractions had a significant inhibitory effect on DNA damage. The IC50 values of TME, defatted fraction and CH2Cl2 fraction against DNA damage were determined as 48, 138 and 8?μg ml?1, respectively. Conclusion: S. lindbergii extracts can prevent oxidative DNA damage, which is likely due to its flavonoids and phenolic compounds as antioxidant constituents.  相似文献   
2.
Stachys tmolea subsp. tmolea Boiss. is endemic to Turkey and is a species of the genus Stachys L. which is one of the largest genera of the family Lamiaceae with about 300 species. The aims of this study were to examine the chemical composition of the essential oil and n-hexane extract of S. tmolea subsp. tmolea as natural sources of insecticidal activity against the dengue vector, Aedes aegypti. Analysis of the essential oil by GC-FID and gas chromatography-mass spectrometry (GC-MS) systems identified hexahydrofarnesyl acetone (15%), viridiflorol (10%), hexadecanoic acid (7%) and 9-geranyl-p-cymene (6%) as major components. The volatile components of the n-hexane extract were extracted using headspace solid-phase microextraction (HS-SPME) and were analyzed using GC-MS. The principal constituents were 3,4-dimethyl decane (16%), 3-methyl-3-pentanol (15%), 2-methyl-2-pentanol (12%), 1,4-bis (1,1-dimethylethyl) benzene (12%), heptanal (10%), acetic acid (6%) and decane (4%). Bioassay of the n-hexane extract, at 5 µg/mosquito, produced 90% mortality against adult Ae. aegypti while the S. tmolea essential oil demonstrated 13% mortality. No larvicidal activity was observed both in essential oil and n-hexane extract. Further studies are needed to assess the adulticidal activity of the responsible compounds in the crude extract.  相似文献   
3.

Ethnopharmacological relevance

Salvia species and Melissa officinalis are used for their memory-enhancing effects in European folk medicine. Teucrium polium was reported to be used in Anatolia for memory-enhancement in a very old book written by an Ottoman herbalist–physician.

Aim of the study

Alzheimer's disease (AD) is a progressive neurological disorder mostly affecting the elder population. Currently, there is no cure for the treatment of severe type of AD. Therefore, in this study, the hydroalcoholic extracts of three traditionally used Lamiaceae species for memory-enhancement; Salvia triloba L., Melissa officinalis L., and Teucrium polium L., were assessed for their in vivo antiamnesic activity along with in vitro anticholinesterase and antioxidant activities.

Materials and methods

Scopolamine-induced antiamnesic activity was determined in mice by passive avoidance test, while anticholinesterase effect was measured by spectrophotometric Ellman method at 0.25, 0.50, 1.0, and 2.0 mg ml−1 and antioxidant activity was assessed by scavenging effect against 2,2-diphenylpicrylhydrazyl (DPPH). Total phenol contents of the extracts were determined by Folin-Ciocalteau method.

Results

Salvia triloba was the most effective in antiamnesic experiment at 100, 200, and 400 mg kg−1 doses having 22.7, 57.1, and 71.4% of relative effects, respectively. Teucrium polium was also active dose-dependently, whereas Melissa officinalis was completely inactive. In the anticholinesterase assay, the extracts showed similar inhibitions against acetylcholinesterase and Teucrium polium had the highest inhibition (65.8% at 1.0 mg ml−1). Concerning the antioxidant effect, all the extracts exerted the highest activity among all having IC50 values between 0.227 and 0.428 mg/ml.

Conclusion

Our data suggest that Teucrium polium among the screened plants deserves to be examined further as a herbal alternative for AD treatment.  相似文献   
4.
A new ent-abietane diterpenoid, 3α,6β-dihydroxy-7,17-dioxo-ent-abieta-15(16)-ene (1), and three known ent-kaurane diterpenids, kamebacetal A (2), kamebakaurin (3), and excisanin A (4), and a known triterpenoid, ursolic acid (5), were isolated from the aerial parts of Isodon inflexus. Their chemical structures were determined by extensive analysis of spectroscopic data including 1D-and 2D-NMR experiments. All isolates (1–5) were evaluated for their potential to inhibit LPS-induced nitric oxide production in RAW264.7 cells. Of these, compounds 1–4 inhibited the production of NO with IC50 values ranging from 1.0 to 26.5 μM.  相似文献   
5.
The present study was undertaken to elucidate the mode of action of methanol extract from aerial parts of L. caulescens (TC-MELc) as spasmolytic agent on in vitro rat ileum test, and investigate the possible antibacterial activity of different extracts from the plant. TC-MELc induced a concentration-dependent (0.001 to 100microg/mL) antispasmodic effect on spontaneous contractions. TC-MELc also (IC50 11.2microg/mL) induced a marked depression on cumulative concentration-response curve for carbachol (Emax=2.3+/-0.3g vs. 0.66+/-0.1g) and serotonin (Emax=1.1+/-0.3g vs. -0.01+/-0.09g). Besides, extract decreased and displaced to the right KCl and CaCl2 concentration-response curves. Moreover, TC-MELc (11.2microg/mL) provoked a total relaxation when ileum strips were contracted with carbachol (1microM) in calcium-free Krebs solution. Pre-treatment with l-NAME (10microM) produced a significant change of the relaxant response and activity was markedly inhibited. Additionally, hexanic (HELc), dichloromethanic (DELc) and methanolic (MELc) extracts from aerial parts were studied to determine their antibacterial activity. DELc showed antibacterial activity on all bacterial strains assayed (相似文献   
6.
Phytochemical investigation of methanol extract from the spikes of Prunella vulgaris L. led to the isolation of two new pentacyclic triterpenoid glycosides Vulgasides I (1) and II (2) along with 13 known compounds (3–15). Their structures were established on the basis of nuclear magnetic resonance (1D and 2D) and mass spectroscopic data analysis. All the isolated compounds were screened for glycogen phosphorylase inhibitory activity and also evaluated for their effect on insulin sensitivity in 3T3‐L1 adipocytes. Two new compounds (1, 2) did not demonstrate the glycogen phosphorylase inhibitory activity, but other compounds (3–11) exhibited varying degrees of glycogen phosphorylase inhibitory activity with IC50 values in the range from 30.69 to 68.85 μM. Compounds 3, 6, 7, 11, and 13 demonstrated markedly increased insulin‐mediated glucose consumption in 3T3‐L1 adipocytes. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
7.
The role of natural products in preventing diseases, such as atherosclerosis, is being recognized increasingly. In this study, the in vitro antioxidant activity of the polar extract obtained from Alkanna albugam root, belonging to the Boraginaceae family, against LDL oxidation, was investigated and compared with the respective activity of Greek Mentha piperita, Rosmarinus officinalis and Sideritis clandestina, belonging to the Lamiaceae family. Of the extracts tested, only those from Alkanna albugam root and Mentha piperita exhibited statistically significant activity. Weaker activity was shown by the extracts obtained from Rosmarinus officinalis and Sideritis clandestina.  相似文献   
8.
Two new tricyclic clerodane-type diterpenoids, limbatolide D (1) and limbatolide E (2), have been isolated from the roots of Otostegia limbata. Their structures and the relative configuration were established on the basis of spectral methods, especially two-dimensional (2D) NMR techniques.  相似文献   
9.

Background and the purpose of the study

The species Hymenocrater calycinus, belongs to the plant family Lamiaceae and grows wildly in the north-east of Iran. Previously, the antimicrobial activity of the plant extracts was reported. In the present study, the bioactivity-guided fractionation of the methanol extract of H. calycinus and the combination effects of the isolated compound with cell wall active agents against S. aureus and E. coli was investigated.

Methods

Column and thin layer chromatographic methods were used for isolation and purification and spectroscopic data (MS, 1H- and 13C-NMR, HMQC, HMBC and 1H-1H COSY) were employed for identification of the compound isolated from the extract. A disk diffusion method was used to determine the antibacterial activity of the isolated compound against S. aureus and E. coli in comparison with 7 different antibiotics.

Results

The isolated compound 1 was identified as 3-(3, 4- dihydroxyphenyl) lactic acid 2-O-quinic acid. Compound 1 (500 µg/disc) enhanced antibacterial effect of ampicillin, ciprofloxacin, vancomycin and cefepime against S. aureus and activated the effects of ampicillin and vancomycin against E. coli.

Conclusion

Results showed that the compound 1 was not active against both tested strains at any concentration below 1 mg/disk, and as a result the enhancing effect of the compound could be due its association with antibiotics.  相似文献   
10.
Abstract

The flavonoids kumatakenin (1), pachypodol (2), 5-hydroxy-7,3′,4′-trimethoxyflavone (3), velutin (4), salvigenin (5), retusin (6) and corymbosin (7) have been isolated from the aerial parts of Ballota glandulosissima Hub.-Mor & Patzak. Among them, 2–4 and 7 have not been reported previously in the genus Ballota. The antibacterial and antifungal activities of 1–4 and 6 were tested against Bacillus subtilis, Staphylococcus aureus, Staphylococcus faecalis, Echerichia coli, Pseudomonas aeruginosa, Candida albicans, Candida krusei and Candida galabrata.  相似文献   
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