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1.
Ether, methanol and aqueous extracts of Centipeda minima (Compositae) herbs were found to have significant anti-allergy activities in passive cutaneous anaphylaxis (PCA) test. Three flavonoids, two sesquiterpene lactones and an amide were isolated from this plant material as inhibitors to induced histamine release from mast cells. The sesquiterpenes were identified as isobutyroylplenolin and senecioylplenolin by spectral investigations. The flavonoids and sesquiterpenes exhibited significant anti-allergy activity in PCA test with p.o. administration.  相似文献   

2.
Summary RPHPLC methods for analysis of photosynthetic pigments (chlorophylls and carotenoids) usually require addition of water to methanol or acetone extracts to prevent distortion of early-eluting peaks corresponding to the more polar compounds. In this work we have investigated the short-(<2 min) and long-term (up to 48 h) effect of adding water to acetone and methanol extracts from two marine phytoplankton species,Emiliania hyxleyi andDunaliella tertiolecta. Solvent extracts were prepared and separated into fractions that were subsequently diluted with water to 90%, 80%, 70%, 60%, 50%, and 40% for methanol, and the same range extended to 30% and 20% for acetone. Changes in pigment concentration with time were followed spectrophotometrically and chromatographically. Losses of pigments as a result of precipitation were clearly observed immediately after dilution of acetone extracts to 60% or less and methanol extracts to 80% or less. For chlorophyll a the most substantial losses were recorded for 50% acetone (up to 27% decrease) and for 70% methanol (31% decrease). This effect increased considerably with time. Only for 90% and 80% acetone were the initial concentrations of all the pigments unchanged after 24h, and even up to 48 h. In contrast, more than 60% and 57% of the initial amounts of chlorophyll a were lost after 24 h in 50% acetone and 70% methanol extracts, respectively. These losses increased to 83% and 60% after 48 h. There was a clear correlation between the polarity of a pigment and the polarity of the solvent at which maximum precipitation occurred. Losses of pigment from pure acetone and methanol extracts with time were also observed, although we attribute these to pigment degradation rather than precipitation. Some of the losses occurring with time can be avoided by use of autosamplers in which the sample can be mixed with water immediately before injection.  相似文献   

3.
屈啸声  林瑞森  方文军 《化学学报》2009,67(23):2692-2696
开发药用植物首先必须确定其活性部位. 我们采用微量热法鉴定了一种植物Vitex negundo Linn的四种不同提取物: 正己烷提取物、氯仿提取物、乙酸乙酯提取物和甲醇提取物对大肠杆菌(E. coli)的抑制作用. 结果表明甲醇提取物对大肠杆菌生长的代谢热谱抑制作用最强. 通过计算该提取物作用下大肠杆菌的生长速率常数, 表明该提取物的抑制作用随浓度的升高而增强.  相似文献   

4.
Oral administration of ethanol to rats at a dose of 3 g/kg decreased alcohol dehydrogenase (ADH) activity and metabolism of lactate to pyruvate in the liver. The effects of water extracts of Aloe and some other herbs on blood ethanol concentration and on ADH activity in liver cytosol were examined. The water extracts of these herbs caused a faster elimination of ethanol from blood of normal rats when administered orally 30 min before oral administration of ethanol. The rapid elimination of ethanol seems to be due to a protection of ADH activity and the supply of nicotinamide dinucleotide, both of which are reduced by high ethanol concentration. The effects of ethanol in decreasing the enzyme activities relating to its own metabolism occur when high concentrations of ethanol pass through the liver, and thus may primarily appear during the absorption of alcohol from the gastrointestinal tract, when portal concentration of ethanol are very high.  相似文献   

5.
Lentinus lepideus is an edible mushroom currently available in Korea. The acetone, methanol and hot water extracts were prepared and assayed for their antioxidant and antityrosinase inhibitory activities. The hot water extract showed the strongest β-carotene-linoleic acid inhibition compared to the other extracts. At 8 mg/mL, the methanolic extract showed a high reducing power of 1.21. The acetone and methanol extracts were more effective in scavenging DPPH radicals than the hot water extract. The strongest chelating effect was obtained from the methanolic extract. Xanthine oxidase and tyrosinase inhibitory activities of the acetonic, methanol and hot water extracts increased with increasing concentration. Gallic acid, chlorogenic acid, vanillin, naringin, naringenin, formononetin, and biochanin-A were detected in the acetonitrile and hydrochloric acid (5:1) solvent extract. This study suggests that fruiting bodies of L. lepideus can potentially be used as a readily accessible source of natural antioxidants.  相似文献   

6.
In a previous paper, we reported that methanol extracts obtained from 13 Chinese traditional medicines showed remarkable choleretic effects in normal rats. This paper examines the protective effects against experimental cholestasis induced by carbon tetrachloride (CCl4) or alpha-naphthylisothiocyanate (ANIT) in rats. No medicines, including sodium dehydrocholate and 1-phenylpropanol which are used clinically as choleretic drugs, inhibited the decrease of bile flow induced by CCl4. On the other hand, Intinko-to, Saiko-seikan-to and Bohu-tusyo-san revealed marked improvement of the dysfunction in bile secretion induced by ANIT. These three medicines inhibited the decrease of excretion of bile acid or bilirubin in the bile. They also exerted a protective effect against the alterations of serum components induced by ANIT, i.e., of glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, alkaline phosphatase and the concentration of serum bilirubin. These results indicate that methanol extracts of Intinko-to, Saiko-seikan-to and Bohu-tusyo-san demonstrate not only choleretic effects but also improvement of cholestasis and liver parenchymal injury in rats.  相似文献   

7.
The effects of 112 extracts prepared from 37 kinds of animal crude drugs and a dog's filaria were investigated on the blood coagulation and fibrinolysis systems in vitro. The plasma recalcification time method was employed for the assay of blood coagulation and fibrinolytic activity was tested by the fibrin plate method. It was found that the water extracts of Bombyx Batryticatus, Carpio Fel and Holotrichiae Vermiculus showed potent inhibitory effects on blood coagulation. The methanol extracts of Phocae Thstis et Penis, Scorpion and Tabanus were promotive effect, on the other hand. As regards the fibrinolysis system, the water extracts of Agkistrodon, Lumbricus, Hirudo, Scolopendra and Scorpion and the methanol extract of Hirudo showed a remarkable activity.  相似文献   

8.
The inhibitory effect of vexibinol, one of the flavanols found in Sophora, on gastric ulcers induced by HCl-ethanol has been reported previously. In the present study, the effect of vexibinol was examined in various experimental ulcer models in order to determine the mechanism of its antiulcer action. The results indicated that the oral administration of vexibinol at 25-50 mg/kg significantly inhibited the development of ulcers induced by HCl-ethanol, 0.6 N HCl 0.2 N NaOH, absolute ethanol and 1% NH3. In addition, an intraduodenal administration of vexibinol at 300 mg/kg significantly inhibited Shay's ulcer. Further, intraduodenal administration at 300 mg/kg significantly inhibited acid secretion caused by 2-deoxy-D-glucose. These results suggest that vexibinol has not only gastric mucosal protective action but also an inhibitory effect on the secretion of gastric acids.  相似文献   

9.
Antiliperoxidant activity of pomegranate peel extracts on lard   总被引:1,自引:0,他引:1  
Phenolics were extracted from powdered pomegranate peel using water, methanol, acetone and ethyl acetate (EtOAc), respectively. The antiliperoxidant activity of the extracts on lard was studied by peroxide value method. All the extracts showed enhanced inhibitory effect on lard peroxidation with the increase of phenolic concentrations. Acetone extract exhibited the highest antiliperoxidant activity followed by water, methanol and EtOAc extracts. Acetone extract at 0.1% (w/w) and water extract at 0.2% (w/w) demonstrated an antiliperoxidant effect close to that of tea polyphenols (0.02%, w/w) and higher than that of BHT (0.02%, w/w). At 0.2% (w/w), acetone extract showed a higher inhibitory activity on lard oxidation than that of tea polyphenols and BHT. Owing to the high antiliperoxidant property, acetone extract may have possible application in the food industry.  相似文献   

10.
The present work was conducted aiming to evaluate the effect of different solvent extracts on the antioxidant and antibacterial activities of Annona squamosa L. leaves. Four solvents were chosen for the study namely; methanol 80%, acetone 50%, ethanol 50% and boiling water. Acetone and boiling water gave the highest extraction yields as compared to methanol and ethanol. Total phenolic contents of the four extracts were significantly different with acetone being the most efficient solvent and water being the least efficient one. Correlation coefficient between the total antioxidant and total phenolic content was found to be R2 = 0.89 suggesting the contribution of phenolic compounds of the extract by 89% to its total antioxidant activity. The extracts were capable of scavenging H2O2 in a range of 43–54%. Reducing power of the extracts increased by increasing their concentration. The extracts were found to exert low to moderate antibacterial activity compared to a standard antibacterial agent. The bacterial inhibition of the extracts was found to positively correlate with their phenolic contents.  相似文献   

11.
The effects of 2-(E-2-decenoylamino)ethyl 2-(cyclohexylethyl) sulfide (compd. III-1a) on various experimental ulcers were investigated. The oral administration of compd. III-1a at doses ranging from 30 to 300 mg/kg inhibited the acute gastric ulcerations induced by ethanol, HCl.aspirin and indomethacin in rats. Compound III-1a significantly inhibited the water immersion stress-induced gastric ulcer at doses of 3 mg/kg, p.o. The anti-ulcer activity of plaunotol as a reference drug was equivalent on an ethanol-induced ulcer to that of compd. III-1a, but weaker on HCl.aspirin, indomethacin and stress-induced ulcers than that of compd. III-1a. On indomethacin-produced gastric antral ulcer, compd. III-1a showed the same significant inhibitory activity as spizofurone did at a dose of 100 mg/kg, p.o. Compound III-1a also inhibited hemorrhagic shock-, diethyldithiocarbamic acid (DDC)-and platelet activating factor (PAF)-induced ulcers dose-dependently. Plaunotol only showed significant inhibitory activity on PAF-induced ulcer in these three ucler models. The consecutive administration of compd. III-1a (100 mg/kg, p.o.) twice a day significantly accelerated the healing of an acetic acid-induced ulcer and that of plaunotol (200 mg/kg, p.o.) showed the same activity. Moreover, orally administered compd. III-1a at a dose of 100 mg/kg decreased the gastric acid secretion in pylorus-ligated rats. The results in the present study suggest that compd. III-1a has the dual action on ulcer formation.  相似文献   

12.
ABSTRACT

The aim of this study was to provide the first from-start-to-end thin-layer chromatographic method of fingerprinting the Cistus incanus L. raw herbal material, with a purpose to further use it for rapid screening, authentication, and quality control of the traded C. incanus L. herbs. To this effect, 12 different C. incanus L. samples purchased as herbal teas from a local market were extracted by means of the accelerated solvent extraction (ASE) with chemometrically optimized solvent extraction mixture and temperature (methanol–water, 27:73, v/v; 130°C), to derive the polar fraction from the plant samples. Then, the extracts were developed in two thin-layer chromatographic systems, both using the commercially precoated silica gel 60 chromatographic plates, yet two different mobile phases (mobile phase 1, ethyl acetate–formic acid–acetic acid–water, 100:11:11:13, v/v/v/v, and mobile phase 2, ethyl acetate–dichloromethane–formic acid–acetic acid–water, 100:10:10:10:11, v/v/v/v/v). The chromatograms were densitometrically scanned in the reflectance mode at the wavelength λ?=?366?nm to obtain fingerprints of the extracts derived from individual C. incanus L. samples. Mobile phase 2 performed slightly better, because with its use, the maximum number of 11 peaks could be seen in the respective fingerprints, whereas with mobile phase 1, the maximum number of 10 peaks only. Then an antioxidant potential of the investigated herbal extracts was assessed, making use of mobile phase 2 and the 0.20% methanol solution of 2,2-diphenyl picrylhydrazyl as a visualizing reagent. The resulting chromatograms were densitometrically scanned in the extinction mode at the wavelength λ?=?550?nm to obtain biological fingerprints of the extracts. Finally, chromatographic and biological fingerprints underwent a semiquantitative evaluation in terms of the contents of the extracted polar fraction and an overall antioxidant potential of the individual plant species.  相似文献   

13.
The plant Krameria pauciflora MOC et. Sessé ex DC. is used as an anti-inflammatory and antidiabetic in traditional medicine. The aim of this study was to evaluate the in vivo anti-inflammatory and antidiabetic effects of a methanol extract from the roots of K. pauciflora. Dichloromethane and ethyl acetate extracts obtained by partitioning the methanol extract were also evaluated. Complete methanol and dichloromethane extracts showed anti-inflammatory effects at 3 mg/kg. An anti-inflammatory effect similar to indomethacin (10 mg/kg) was observed when the methanol and dichloromethane extracts, which contain a cycloartane-type triterpene and an sterol, were administered orally at several doses (3, 10, 30 and 100 mg/kg), whereas no anti-inflammatory effect was observed at any dose for the ethyl acetate extract, which contains catechin-type flavonoids. The antidiabetic effect of each extract was also determined. An antihyperglycaemic effect was observed in diabetic rats, but no effect in normoglycaemic animals was observed when the methanol extract was administrated at 30 mg/kg. All of the extracts exhibited radical scavenger activity. Additionally, constituents from all of the extracts were identified by NMR. This article supports the use of K. pauciflora as an anti-inflammatory because it exhibits a similar effect to indomethacin. However, its antidiabetic effect is not completely clear, although it could be useful for preventing diabetic complications.  相似文献   

14.
陈勇  李紫  蔡敏 《分析科学学报》2004,20(2):117-120
报道了采用电喷雾-质谱负离子全扫描法,分析山麦冬、麦冬对照药材的甲醇提取物。经分析发现,山麦冬、麦冬对照药材负离子的全扫描质谱图差异显著,从中选择16强峰建立山麦冬、麦冬对照药材甲醇提取物的特征图谱。研究表明,该分析方法有较好的重现性,图谱特征性强,可快速、准确鉴别山麦冬、麦冬药材。  相似文献   

15.
《Analytical letters》2012,45(18):2675-2686
Antarctic krill crude extracts contain high levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Accordingly, the solid phase extraction of EPA and DHA from Antarctic krill crude extracts has attracted significant research interest. This study compared the extraction of EPA and DHA from Antarctic krill crude extracts using an aminopropyl, zinc ion-doped silica, and C18 and zinc ion-doped C18 solid-phase column. The best extraction effect was obtained using the zinc ion-doped C18 SPE with water containing methanol as the eluant. The efficiency increased gradually with increasing methanol concentration from 12.5 to 25% in the washing stage, and when pure methanol (5.0 mL) or acetonitrile (3.0 mL) was used as the eluant. To detect EPA and DHA, the acids were first converted to their methyl esters and detected by gas chromatography with flame ionization detection (GC–FID). In the zinc ion-doped C18 elution fractions, EPA and DHA were isolated from the crude extracts in high yield (85–91% (r2 = 4.8–6.3%)).  相似文献   

16.
In this study, we evaluate the antioxidant properties of the various extracts of Protaetia brevitarsis Lewis (Coleoptera: Scarabaedia) at different growth stages. The antioxidant activities of six different extracts from larvae, pupae and imago were measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) and singlet oxygen (1O? ). The larval methanol extracts (LME) and imago methanol extracts (IME) displayed the greatest effect in DPPH and ABTS radical scavenging assay, but the activity of water extracts was weaker in the all tested assays. However, LME and IME could be compared to ascorbic acid in 1O? quenching ability (the effective concentrations of 50% 1O? quenching: EC?? 0.174, 0.149 and 0.177?mg?mL?1, respectively). The antioxidant ability of the extracts to scavenge free radicals could significantly change the contents of gallic acid equivalent, an important factor based on the value of R2. The results suggest that our study may contribute to the development of new bioactive products with potential applications to reduce oxidative stress as well as play a vital role in protecting insect organisms against oxidative damage caused by undesirable conditions.  相似文献   

17.
In the present study, the potential effects of extracts from the whole plant of Cuscuta arvensis were studied in mice using the carrageenan-induced hind paw edema model for antiinflammatory activity and the p-benzoquinone-induced writhing reflex for the assessment of antinociceptive activity. In order to obtain the extracts, the whole plant of C. arvensis was extracted with different solvents such as n-hexane, dichloromethane, ethyl acetate, methanol and distilled water. Antioxidant activity was evaluated by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. The methanolic and water extracts inhibited the carrageenan-induced paw edema and p-benzoquinone-induced writhing reflex, whereas the other extracts showed only mild inhibitory antinociceptive and antiinflammatory activities in these in vivo models. Additionally, the methanol and ethyl acetate extracts had higher scavenging ability then the non polar extracts.  相似文献   

18.
The potential genotoxic effects of methanolic extracts of Euphorbia hirta which is commonly used in traditional medicine to treat a variety of diseased conditions including asthma, coughs, diarrhea and dysentery was investigated using Allium cepa assay. The extracts of 125, 250, 500 and 1,000 μg/mL were tested on root meristems of A. cepa. Ethylmethanesulfonate was used as positive control and distilled water was used as negative control. The result showed that mitotic index decreased as the concentrations of E. hirta extract increased. A dose-dependent increase of chromosome aberrations was also observed. Abnormalities scored were stickiness, c-mitosis, bridges and vagrant chromosomes. Micronucleated cells were also observed at interphase. Result of this study confirmed that the methanol extracts of E. hirta exerted significant genotoxic and mitodepressive effects at 1,000 μg/mL.  相似文献   

19.
In this study, the Caco-2 cell monolayer model was used to research the characteristic absorption and efflux of five diterpenoid alkaloids in Gancaofuzi decoction. An ultra performance liquid chromatography coupled with tandem mass spectrometry(UPLC–MS/MS) method was developed for the determination of the simulated intestinal transport of five diterpenoid alkaloids with reserpine as internal standard. The use of the apparent permeability coefficient(Papp) and efflux rate(Er) was instituted to evaluate the intestinal absorption of the alkaloids. Transport of the five alkaloids in Caco-2cell monolayer model was observed to better understand whether the intestinal absorption of alkaloids was influenced by the compatibility of four herbs in Gancaofuzi decoction. The results show that the Papp values of the five diterpenoid alkaloids were all more than 1 * 10~(-6)cm/s, confirming that the processes of permeability were valid. The flux of the alkaloids was time-dependent, and the intestinal absorption mechanism of the five alkaloids was mainly based on passive transport. The compatibility of Heishunpian, Baizhu, Guizhi and Gancao can reduce the intestinal absorption of alkaloids, especially the most toxic hypaconitine, and the attenuated effect of mixed herbal water extracts was better than that of different herbs' water extracts combination. The results prove that compatibility of four herbs in Gancaofuzi decoction is rational.  相似文献   

20.
An optimized method using liquid chromatography coupled with electrospray ionization ion trap mass spectrometry (LC/ESI-ITMS) in negative ion mode has been developed for screening different structural classes of intact glucosinolates in six Chinese medicinal herbs. The glucosinolates were extracted with hot methanol/water (70:30 v/v) and separation of the individual glucosinolates was achieved using a reversed-phase C18 column with an aqueous ammonium acetate/methanol gradient. Identification of the intact glucosinolates was based on the detection of compounds with a constant neutral loss of 242 Da corresponding to the combined loss of anhydroglucose (162 Da) and sulfur trioxide (80 Da) in collision-induced dissociation. The structures of the identified glucosinolates were confirmed with the use of group-specific product ions at m/z 195, 241, 259, 275 in their corresponding MS/MS product ion spectra. Differentiation of intact glucosinolates was achieved through their respective retention times and molecular masses as well as the characteristic product ions. The limits of detection were at the low nanogram level per injection, based on constant neutral loss scans. Significant variation in the compositions of intact glucosinolates was identified in the cruciferous herbs. This method was applied in the differentiation and quality control of two pairs of easily confused herbs. Copyright (c) 2008 John Wiley & Sons, Ltd.  相似文献   

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