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1.
Baccharis trimera is a plant popularly used as a tea and to treat gastrointestinal diseases and inflammatory processes as well. The total phenolic content was determined and the antioxidant and anti-inflammatory activities of six extracts (dichloromethane, ethyl acetate, butanol, aqueous, saponin and phenolic) from B. trimera were evaluated. Using carrageenan-induced pleurisy as a model of acute inflammation, the phenolic extract at 15 mg/kg decreased significantly the analyzed parameters when compared to the carrageenan group ( p < 0.05), thus showing potential anti-inflammatory activity. The total phenolic content and antioxidant activity were evaluated by the Folin-Ciocalteau and DPPH methods, respectively. Phenolic and ethyl acetate extracts presented higher antioxidant activity ( p < 0.05) than ascorbic acid. The phenolic extract also showed the highest antioxidant potential in relation to the other extracts, thus suggesting that the antioxidant and anti-inflammatory activities were due to the presence of phenolic compounds.  相似文献   

2.
Evaluation of the antioxidant activity of Syzygium cumini leaves   总被引:1,自引:0,他引:1  
The antioxidant activity of Syzygium cumini leaf extracts was investigated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical-scavenging and ferric-reducing antioxidant power (FRAP) assays. The methanolic extract and its four water, ethyl acetate, chloroform, and n-hexane fractions were prepared and subjected to antioxidant evaluation. The results showed that the ethyl acetate fraction had stronger antioxidant activity than the other ones. HPLC data indicated that S. cumini leaf extracts contained phenolic compounds, such as ferulic acid and catechin, responsible for their antioxidant activity. A significant linear relationship between antioxidant potency, free radical-scavenging ability and the content of phenolic compounds of leaf extracts supported this observation.  相似文献   

3.
Chemical composition of the hydrodistilled volatile fraction from flowers of four Staphylea L. species (Staphylea colchica Stev., Staphylea elegans Zab., Staphylea holocarpa Hemsl., Staphylea pinnata L.) was determined by the GC/MS method. Compounds in fresh and dried flowers (stored for 1 year) were determined. Mostly, structures of different oxygenated aliphatic hydrocarbons in all four species were found. Different aldehydes, ketones, esters of higher fatty acids, and hexadecanoic acid were identified, with dominating content of tricosane, hexadecanoic acid and also of heneicosane, pentacosane, heptacosane, and nonacosane. In S. pinnata L. (fresh flowers) some nonaliphatic hydrocarbons, and in S. holocarpa Hemsl. (fresh flowers) esters of higher fatty acids were found.  相似文献   

4.
Phenolic and flavonoid contents in leaf extracts of Bergenialigulata have been analysed for their contribution in antimicrobial and antioxidant activities. The extracts were prepared in three solvents (separately) following maceration and soxhelt methods. The antimicrobial activity was tested using disc diffusion assay against a range of microorganisms along with the determination of minimum inhibitory concentration (MIC), while the antioxidant activity was tested following DPPH assay. Leaf extracts exhibited antimicrobial activity against all the three groups of microorganisms; results coincided with respective MIC. In general, the methanol extracts prepared through maceration favoured the determination of antimicrobial and antioxidant activities. Maximum values for phenolic and flavonoid contents were obtained in macerated methanol and ethyl acetate extracts, respectively. The statistical correlations exhibited the extent of the contribution of phenolic and flavonoid contents in antimicrobial and antioxidant activities and also indicated the involvement of other plant metabolites.  相似文献   

5.
Flowers of Helichrysum plicatum were extracted under different experimental conditions, and their antioxidant activity was determined by DPPH radical scavenging assay. Extracts obtained with higher concentration of ethyl acetate (90% or 100%) were found to contain the greatest amount of total phenolics (> 250 mg gallic acid equivalents/g of dried extract), and high correlation between total phenolic content and antiradical activity was observed (r = -0.79). Based on the total phenolic content and antiradical activity, some extracts were selected for investigation of cytotoxic activity toward PC3, HeLa and K562 human cancer cell lines in vitro. All tested extracts exhibited moderate activity against HeLa cells (41.9-42.1 microg/mL), whereas the extract obtained with 100% ethyl acetate was the most active against K562 and PC3 cell lines (25.9 and 39.2 microg/mL, respectively). Statistical analysis revealed significant correlation between total phenolic content and cytotoxic activity against PC3 and K562 cells. HPLC identification of phenolic compounds from the extracts indicated the presence of apigenin, naringenin and kaempferol as free aglycones, and glycosides of apigenin, naringenin, quercetin and kaempferol. Among aglycones, kaempferol displayed moderate cytostatic activity against all cell lines (24.8-64.7 microM).  相似文献   

6.
Phytochemicals such as polyphenols and carotenoids are gaining importance because of their contribution to human health and their multiple biological effects such as antioxidant, antimutagenic, anticarcinogenic, and cytoprotective activities and their therapeutic properties. Banana peel is a major by-product in pulp industry and it contains various bioactive compounds like polyphenols, carotenoids, and others. In the present study, effect of ripening, solvent polarity on the content of bioactive compounds of crude banana peel and the protective effect of peel extracts of unripe, ripe, and leaky ripe banana fruit on hydrogen peroxide-induced hemolysis and their antioxidant capacity were investigated. Banana (Musa paradisica) peel at different stages of ripening (unripe, ripe, leaky ripe) were treated with 70% acetone, which were partitioned in order of polarity with water, ethyl acetate, chloroform (CHCl3), and hexane sequentially. The antioxidant activity of the samples was evaluated by the red cell hemolysis assay, free radical scavenging (1,1-diphenyl-2-picrylhydrazyl free radical elimination) and superoxide dismutase activities. The Folin–Ciocalteu's reagent assay was used to estimate the phenolic content of extracts. The findings of this investigation suggest that the unripe banana peel sample had higher antioxidant potency than ripe and leaky ripe. Further on fractionation, ethyl acetate and water soluble fractions of unripe peel displayed high antioxidant activity than CHCl3 and hexane fraction, respectively. A positive correlation between free radical scavenging capacity and the content of phenolic compound were found in unripe, ripe, and leaky ripe stages of banana peel.  相似文献   

7.
In the present study, we report for the first time the antioxidant and antimicrobial activities of Withania frutescens (L.) Pauquy roots and leaves. Total phenolic content was determined using the Folin-Ciocalteu method and antioxidant activity was evaluated by the DPPH free radical scavenging and reducing power methods. Antimicrobial activity tests were carried out against ten bacterial species involved in nosocomial infections and two opportunistic clinical yeast isolates. The ethyl acetate and n-butanol leaf fractions exhibited the highest DPPH radical scavenging activity with IC50 = 4.53 +/- 0.12 and 8.49 +/- 0.46 microg/mL, respectively. The n-butanol root fraction showed the greatest reducing power comparable with that of quercetin at 0.4 mg/mL. The dichloromethane leaf fraction exhibited the highest antibacterial activity against both Gram-positive and Gram-negative bacteria with MIC values ranging between 50 and 400 microg/mL, depending on the tested bacteria. However, none of the examined extracts exhibited anticandidal activity. The polyphenol and glycowithanolide constituents appeared to be responsible for the antioxidant capacity of W. frutescens, whereas the observed antimicrobial activity may be due to the presence of withanolides.  相似文献   

8.
The antioxidant activity of the phenolic compounds present in industrial black liquors obtained from the two cooking processes (kraft and sulphite) used in Portugal to produce Eucalyptus globulus pulp was evaluated. The black liquors treated at several pH values were extracted with ethyl acetate. Phenolic fractions were further separated by liquid chromatography of the crude extracts of kraft liquor at pH = 6 and sulphite liquor at the original pH. Total phenolic content was determined in terms of gallic acid equivalents (Folin-Ciocalteu colorimetric method), and the antioxidant activity in the crude extracts at several pH values and in the separated fractions was measured using the DPPH test for radical scavenging capacity. The total phenolic content of crude extracts and separated fractions ranged from 92.7 to 181.6 and from 91.6 to 1,099.6 mg GAE/g, respectively, while the antioxidant activity index (AAI) ranged from 2.20 to 3.41 and from 2.21 to 11.47 respectively, showing very strong antioxidant activity in all studied cases. The fractions separated by column chromatography were submitted to mass spectrometry analysis and the results were compared to others in the literature of natural products, mainly from Eucalyptus, and the characteristic bands of functional groups were identified by 1H-NMR and FTIR. These methods allowed the identification of 17 phenolic compounds.  相似文献   

9.
This study is designed to examine the chemical composition of the essential oil and antioxidant activities of the different extracts of Tanacetum sonbolii Mozaff. from Iran for the first time. The essential oil was isolated by hydrodistillation and its gas chromatography and gas chromatography-mass spectrometry analyses resulted in the identification of 26 components, representing 96.5% of the oil. The major components were characterised to be α-cadinol (35.3%), globulol (20.1%) and 1,8-cineole (8.6%). Antioxidant activities of the various extracts of the plant were determined by two different test systems; 1,1-diphenyl-2-picrylhydrazyl (DPPH) and β-carotene-linoleic acid. Also, their total phenolic and flavonoid contents were determined. DPPH radical-scavenging activities of test samples followed the order water?>?chloroform?>?ethyl acetate?>?butanol?>?BHT?>?methanol. Moreover, the ethyl acetate extract showed better β-carotene bleaching capacity than the other extracts and the amount of total phenolics was very high in ethyl acetate extract.  相似文献   

10.
We evaluated the in vitro antioxidant property and phytochemical constituents of the crude ethyl acetate and methanol extract of the three genders of carob tree barks (spontaneous male, spontaneous female, and grafted female). The scavenging activity on DPPH (1,1-diphenyl-2-picrylhydrazyl) was determined, as well as the phenolic contents (Folin–Ciocalteu method) of both the extracts. The highest antioxidant activity and the higher amounts of total phenols were shown in methanol crude bark extract for the three genders. Variety significantly affected the phenol content and the antioxidant activity, with the spontaneous male variety globally showed a higher polyphenol concentration and antioxidant activity than the grafted female and spontaneous female.  相似文献   

11.
Plant-derived antioxidant compounds have the potential to prevent cell damage caused by free radicals. As a holoparasitic plant, Cuscuta campestris Yuncker is being valorized for treatment of liver injury and cancer prevention in traditional medicine. The main purpose of this present study is to elucidate the antioxidant- and anticancer-associated contents of C. campestris by spectroscopic and chromatographic methods. Diethyl ether, ethyl acetate, methanol, n-butanol, and water were used as extraction solvents to reach a wide range of secondary metabolites synthesized by this plant. Antioxidant potentials of these extracts were characterized by (2,2-diphenyl-1-picrylhydrazyl)-free radical scavenging activity. Their anticancer activities were evaluated on SNU-398 hepatocellular carcinoma cells and controlled on the normal adult human dermal fibroblasts (hDFs) cells. Their phenolic compounds were analyzed by high-performance liquid chromatography with diode array detector to illuminate the responsible anticancer agent(s). The ethyl acetate extract revealed the most significant antioxidant effect. Methanol and ethyl acetate extracts were found to be cytotoxic on the SNU-398 cell lines with CC50 values of 18.7 and 19.6?µg?mL?1, respectively, whereas these extracts were not cytotoxic to the adult hDFs cells. Due to their abundance in the extracts, isorhamnetin, kaempferol, and quercetin may have caused this anticancer activity. Methanol extract has the highest concentration of phenolic compounds. Based on chromatographic analyses, we propose that these anticancer effects were positively correlated with plant phenolic compounds. The results showed that this plant is worth further study for its therapeutic uses.  相似文献   

12.
Antioxidant activity of papaya seed extracts   总被引:1,自引:0,他引:1  
The antioxidant activities of the ethanol, petroleum ether, ethyl acetate, n-butanol and water extract fractions from the seeds of papaya were evaluated in this study. The ethyl acetate fraction showed the strongest DPPH and hydroxyl free radical-scavenging activities, and its activities were stronger than those of ascorbic acid and sodium benzoate, respectively. The n-butanol fraction demonstrated the greatest ABTS? radicals scavenging activity. The ethyl acetate fraction and the n-butanol fraction not only showed higher antioxidant activities than the petroleum ether fraction, water fraction and ethanol fraction, but also showed higher superoxide anion and hydrogen peroxide radicals scavenging activities than those of the other extract fractions. The high amount of total phenolics and total flavonoids in the ethyl acetate and n-butanol fractions contributed to their antioxidant activities. The ethyl acetate fraction was subjected to column chromatography, to yield two phenolic compounds, p-hydroxybenzoic acid and vanillic acid, which possessed significant antioxidant activities. Therefore, the seeds of papaya and these compounds might be used as natural antioxidants.  相似文献   

13.
The antioxidant efficiency of dry extracts from inflorescences and/or leaves of seven Sorbus species was studied using four in vitro tests of SET (single electron transfer) and HAT-type (hydrogen atom transfer) mechanisms. The 70% methanol extracts and its diethyl ether, ethyl acetate, n-butanol and water fractions were tested in parallel with the phenolic standards, e.g., caffeic acid, quercetin, BHA, BHT, and Trolox. The SET-type activity of the extracts depended primarily on the extraction solvent. The most valuable extracts were n-butanol and ethyl acetate ones, which activity was high in the DPPH (EC(50) = 3.2-5.2 μg/mL), TEAC (2.8-4.0 mmol Trolox/g), and FRAP (9.8-13.7 mmol Fe2+/g) tests, and strongly correlated with the total phenolic levels (39.6-58.2% of gallic acid equivalents). The HPLC-PDA analysis of the extracts led to the identification of chlorogenic acid, isoquercitrin, hyperoside, rutin, quercetin 3-O-sophoroside, and sexangularetin 3-O-β-D-glucopyranoside as the main components. Apart from flavonoids and hydroxycinnamic acids, proanthocyanidins have also a significant impact on the SET-type activity. The HAT-reactivity of the extracts in the linoleic acid peroxidation test (IC(50) = 36.9-228.3 μg/mL) depended more strongly on the plant tissue than on the extraction solvent, and its correlation with the phenolic content was weak. Both SET and HAT-type activity of the most potent Sorbus extracts was comparable with the activity of the standards, indicating their great potential as effective sources for health products.  相似文献   

14.
Euryale ferox has been widely used in traditional oriental medicine to treat a variety of illness. However, very little is known about the cellular actions by which this plant mediates its therapeutic effects. Various aspects of antioxidant activity were evaluated in total extracts and fractions derived from Euryale ferox. Total extracts (IC50 5.6 microg/ml) showed relatively high level radical scavenging activity toward 1, 1-diphenyl-2-picrylhydrazyl (DPPH) and also enhanced viability of Chinese hamster lung fibroblast (V79-4) cells under exposure to oxidative agents. Upon further fractionation, the highest levels of DPPH radical scavenging and lipid peroxidation inhibitory activities were found in the ethyl acetate and butanol fractions. The ethyl acetate fractions, the butanol fractions, and total extracts of Euryale ferox also dose-dependently enhanced the activities of superoxide dismutase, catalase and glutathione peroxidase in V79-4 cells. Of these three antioxidant enzymes, glutathione peroxidase activity was most strongly induced. Taken together, our findings show that Euryale ferox contains a significant antioxidant activity and that specific components in the ethyl acetate and butanol fractions may play an important role in mediating these antioxidant properties.  相似文献   

15.
This study was designed to evaluate the in vitro antioxidant activities of n-hexane (Hex), dichloromethane (DCM), methanol (MeOH) and essential oils (EO) extracts obtained from Salvia euphratica var. euphratica and Salvia euphratica var. leiocalycina and to determine their essential oil and phenolic acid compositions. The samples were screened for their antioxidant activity by using DPPH and β-carotene/linoleic acid assays. Methanol extracts of both varieties exhibited strong antioxidant activities. Our results showed that rosmarinic acid was dominant phenolic acid of MeOH extracts (39.4 and 55.8?μg?mg?1, respectively). The chemical compositions of essential oils of two varieties were analysed and their main components were determined as eucalyptol (18.4%) and trans-pinocarvyl acetate (24.9%), respectively. It can be said that these varieties could be used as natural antioxidant.  相似文献   

16.
This study was conducted to investigate the chemical and nutritional composition of Artemisia annua leaves in addition to determination of antioxidant potential of their extracts prepared in different solvents. Chemical composition was determined by quantifying fat, protein, carbohydrate, fiber, tocopherol, phytate, and tannin contents. Extraction of A. annua leaves, for antioxidant potential evaluation, was carried out using five solvents of different polarities, i.e., hexane, chloroform, ethyl acetate, methanol and water. Antioxidant potential was evaluated by estimating total phenolic (TPC), flavonoid (TFC) contents, ferric reducing antioxidant power (FRAP), Trolox equivalent antioxidant capacity (TEAC), DPPH radical scavenging activity and lipid peroxidation. Efficiency of different solvents was compared for the yield of antioxidant extracts from leaf samples and a clear variation was observed. The highest TPC, TFC, TEAC, DPPH radical scavenging and lowest lipid peroxidation were observed in MeOH extracts, whereas aqueous extract exhibited high ferric reducing antioxidant power; suggesting MeOH to be the most favorable extractant.  相似文献   

17.
An aqueous acetone extract of the stem with the leaves of Bauhinia rufescens and its fractions were analysed for their antioxidant and enzyme-inhibitory activities, as well as their phytochemical composition. For measurement of the antioxidant activities, the 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azinobis(3-ethylbenzoline-6-sulphonate) and the ferric-reducing methods were used. The results indicated that the aqueous acetone, its ethyl acetate and n-butanol fractions possessed considerable antioxidant activity. Further, the xanthine oxidase and lipoxygenase inhibitory assays showed that the n-butanol fraction possessed compounds that can inhibit both these enzymes. In the phytochemical analysis, the ethyl acetate and the n-butanol fractions of the aqueous acetone extract were screened by HPLC-MS for their phenolic content. The results indicated the presence of hyperoside, isoquercitrin, rutin quercetin, quercitrin, p-coumaric and ferulic acids in the non-hydrolysed fractions. In the hydrolysed fractions, kaempferol, p-coumaric and ferulic acids were identified.  相似文献   

18.
Xia DZ  Yu XF  Zhu ZY  Zou ZD 《Natural product research》2011,25(20):1893-1901
The total phenolic and flavonoid, antioxidant and antibacterial activities of six Sonchus wild vegetables (Sonchus oleraceus L., Sonchus arvensis L., Sonchus asper (L.) Hill., Sonchus uliginosus M.B., Sonchus brachyotus DC. and Sonchus lingianus Shih) in China were investigated. The results revealed that S. arvensis extract and S. oleraceus extract contained the highest amount of phenolic and flavonoid, respectively. Among the methanol extracts of six Sonchus species, S. arvensis extract exhibited the highest radical (DPPH and ABTS+ scavenging power and lipid peroxidation inhibitory power. It also exhibited the highest reducing power at 500?μg?mL?1 by A (700)?=?0.80. The results of antibacterial test indicated that the S. oleraceus extract showed higher activity than the other five Sonchus wild vegetables extracts, both in Gram-negative bacteria (Escherichia coli, Salmonella enterica and Vibrio parahaemolyticus) and in a Gram-positive bacterium (Staphylococcus aureus). These results indicate that Sonchus wild food plants might be applicable in natural medicine and healthy food.  相似文献   

19.
Numerous diseases are induced by free radicals via lipid peroxidation, protein peroxidation and DNA damage. It has been known that a variety of plant extracts have antioxidant activity to scavenge free radicals. Campomanesia adamantium (Myrtaceae) is a small tree with edible fruit, commonly known as "guavira" or "guabiroba-branca" that has been used in popular medicine as depurative anti-diarrhoeic, antiinflammatory, anti-rheumatic and to liver diseases. In this study, the antiradical activities of ethanol crude extract of the leaves from C. adamantium and the ethyl acetate and butanol fractions obtained by partition, were determined using DPPH (2,2-Diphenyl-1-picrylhydrazyl radical) and ORAC-FL (Oxygen Radical Absorbance Capacity) assays. The total phenol content in the samples was estimated by Folin Ciocalteau method (FCR). In an initial evaluation the ethanolic extract and the fractions ethyl acetate and butanol have shown levels of phenolic compounds between 15- 74 mg GAE/g in FCR assay, showed DPPH free-radical scavenging activity with SC50 in the range of 7.77-13.35 microg/mL and demonstrated antioxidant capacity between 2648-3502 micromol TE/g of extract and fractions in the ORAC-FL assay. HPLC-DAD and ESI-MS analysis revealed were that the extract of the leaves of C. adamantium studied appears to contain flavonoids as major constituents, including isoquercetrin and quercetin that exhibit proven antioxidant activity.  相似文献   

20.
The antioxidant activities of water extract (WE), ethanol extract (EE), residue water extract (RWE) and petroleum ether (PF), ethyl acetate (EF), n-BuOH (BF) and water (WF) fractions of the ethanol extract from Eupatorium Lindley DC were investigated for the first time. Total phenolics content, DPPH radical scavenging activities, superoxide radical scavenging activities, total reduction capability, and ferrous ions chelating activities were determined for all the extracts and fractions. The results showed that all the extracts and fractions exhibited antioxidant activities with different magnitudes of potency. Among all the samples, WE and RWE exhibited the best antioxidant capacities, the BF also exhibited high antioxidant abilities in all tests except for the metal chelating activity, while the other extracts and fractions were relatively weak antioxidants. The BF had the highest total phenolics contents in all extracts and fractions, and the WE and RWE were found to be rich in tannins. Furthermore, the content of total phenolics showed good correlation with DPPH radical scavenging activity, superoxide anion radical scavenging activity, and the reducing power. Phenolic composition of all the extracts and fractions was identified and quantified by HPLC. The results indicate that the extracts of E. Lindley DC might be a useful potential source of natural antioxidant ingredients.  相似文献   

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