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1.
Seven Hawthorn extracts were tested in isolated guinea pig aorta rings. The effect on noradrenaline- (10 microM) induced contraction was investigated. The extracts were prepared using ethanol (40 to 70% v/v), methanol (40 to 70% v/v), and water as the extraction solvents. The aqueous-alcoholic extracts displayed similar spectra of constituents. They were characterised by similar procyanidin, flavonoid, total vitexin and total phenols content and by similar TLC fingerprint chromatograms. The aqueous extract, however, showed a different fingerprint and a noticeably lower concentration of procyanidins, flavonoids and total phenols but a similar total vitexin content. All 7 extracts had a relaxant effect on the aorta precontracted by noradrenaline and led to relaxations to 44 until 29% of the initial values. The EC50 values of the aqueous-alcoholic extracts varied between 4.16 and 9.8 mg/l. The aqueous extract produced a similarly strong maximal relaxation as the other extracts, but the EC50, at 22.39 mg/l, was markedly higher. The results show that Hawthorn extracts with comparable quality profiles were obtained by using aqueous-alcoholic extraction solvents (40 to 70% ethanol or methanol). The extracts exerted comparable pharmacological effects. When using water as the extraction solvent, both, the spectrum of constituents and the pharmacological effect, deviated remarkably. It is thus possible to obtain bioequivalent extracts with comparable effect profiles by using 40 to 70% ethanol or methanol as the extraction solvent.  相似文献   

2.
采用紫外-可见分光光分度法测定裸花紫珠等7种紫珠属植物水提液中总黄酮、总酚酸的含量及清除自由基的能力.结果表明:7种植物中的总黄酮、总酚酸含量差异很大,均以红紫珠含量最高,其黄酮、总酚酸含量分别为3.75%和2.93%;清除自由基能力与总黄酮、总酚酸含量呈正相关性,亦以红紫珠清除自由基能力最强.研究结果将为紫珠属植物资源的开发与利用提供理论基础.  相似文献   

3.
A simple purification method has been developed in which flavonoid compounds are selectively adsorbed onto a polycarboxyl ester resin (XAD-7) from methanol extract of ginkgo leaves. When 1.0 g dried gingko leaves was extracted with 100 ml of methanol, about 98% of total flavonoid compounds was recovered by selective adsorption. The pH did not affect the adsorption of flavonoids but at high pH the chemical structure of flavonoids was changed and the adsorption decreased to almost zero. As the solution polarity played a key role in the selective adsorption, the amount of water added to the methanol extract was critical for the recovery and loading of flavonoids. Using standard flavonoids, kaempferol and quercetin, the optimal water content was 80% and the recovery was 80% with 10 g of resin dosage/l.  相似文献   

4.
Evaluation of antioxidant and anticancer activities were screened by various Saururus chinensis root extracts. Four solvents (ethyl acetate, methanol, ethanol, and water) extracts were investigated for their total flavonoids, phenol contents and their antioxidant activity of DPPH (2,2-diphenyl-1-picrylhydrazyl), NO (nitric oxide), H2O2 (hydrogen peroxide), ABTS 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonicacid)diammonium assays, FRAP (ferric reducing ability of plasma) assays and anticancer activity. The total phenolic and flavonoid content of extracts were determined by using FC (Folin–Ciocalteu) and AlCl3 colorimetric assay method. Total flavonoid content in these plants ranged from 24.7 to 72.1 mg g?1 and amount of free phenolic compounds was between 11.2 and 67.1 mg g?1 extract. The all extracts have significant levels of phenolics and flavonoids content. Anticancer activity was screened for MCF-7 breast cancer cell line. Ethanol extract shows significant of antioxidant activity and water extract shows significant of anticancer activity compared with standard (BHT) butylated hydroxy toluene. These ethanol and water extracts could be considered as a natural source for using antioxidant, and anticancer agents compared to commercial available synthetic drugs.  相似文献   

5.
红花桑寄生叶提取物的抗氧化活性及酚类物质分析   总被引:4,自引:0,他引:4  
采用DPPH法、TEAC法、FRAP法对红花桑寄生叶不同溶剂提取物的抗氧化活性进行体外评价,并测定其总酚、总黄酮含量。结果表明,溶剂种类对红花桑寄生叶提取物的得率、总酚、总黄酮及抗氧化活性影响显著。在3种评价方法中,不同溶剂提取物的抗氧化活性均表现出不同程度的量效依赖关系。3种溶剂提取物的抗氧化活性强弱依次为丙酮提取物 >甲醇提取物 >水提取物,其中80%丙酮提取物(总酚含量最高,达276.83mg/g)抗氧化活性最强,清除DPPH自由基能力EC50值为0.247,FRAP值(FeSO4 mmol/100g)为115.81,浓度为1.0mg/ml时,TEAC值为2.04。  相似文献   

6.
张勇  谢丽源  熊丙全  曾明 《应用生态学报》2003,14(12):2233-2236
银杏根系甲醇溶提物对离体培养条件下丛枝菌根真菌生长发育的试验结果表明,银杏根系甲醇溶提物对离体条件下丛枝菌根真菌(Glonus mosseae,Gigaspora margarita)生长发育有明显的促进作用,能显著提高孢子萌发率,增加菌丝生长长度。与对照相比,浓度为20%~100%的甲醇溶提物均可显著促进丛枝菌根真菌的生长发育,80%甲醇溶提物效果最明显,银杏根系甲醇溶提物中含丰富的黄酮类化合物,溶提物中黄酮类物质的含量与甲醇洗脱剂的浓度有关,当浓度为80%时,黄酮含量最高,对银杏根系甲醇溶提物中黄酮类化合物含量与丛枝菌根真菌生长发育相关性分析发现,溶提物中黄酮类化合物含量与离体条件下丛枝菌根真菌孢子的生长发育表现为极显著的正相关关系,溶提物中黄酮含量越高,其对丛枝菌根真菌孢子的生长发育促进作用越大。  相似文献   

7.

Microalgae are photosynthetic eukaryotes which are primary producers in the food chain and also excellent sources for bioactive compounds such as alkaloids, flavonoids, phenols, saponins and other fine chemicals. In the present study, the microalga Scenedesmus bajacalifornicus BBKLP-07 was subjected to soxhlet extraction using solvents like chloroform, acetone, ethanol, methanol and aqueous solvents. All the solvents were tested for the presence of phytochemical constituents such as alkaloids, flavonoids, glycosides, phenols, lignin’s, saponins, sterols, tannins, anthraquinone and reducing sugar using the standard procedures. Furthermore, all the crude extracts were subjected to antidiabetic, antioxidant, anti-inflammatory and antimicrobial activities. Antidiabetic activity of the microalgal extracts was observed maximum in Aqueous extract. Methanolic extracts have shown maximum antioxidant activity and chloroform extracts have exhibited highest anti-inflammatory effects. Antimicrobial activities were tested against E.coli, S, typhi, C.perfringens and B.subtilis bacteria and fungi A.niger, and C. albicans. Therefore, the green microalga Scenedesmus bajacalifornicus BBKLP-07 is a rich source of biological active compounds and nutraceuticals and can be exploited for commercial applications.

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8.
The present study aims to investigate the levels of polyphenols and antioxidant activity in one of the most important commercial species of seaweeds in Kamchatka, an edible brown seaweed Saccharina bongardiana. Six extracts of S. bongardiana, acetone, methanol, ethanol, and the respective 70 % aqueous solutions, were assessed for total phenol content in order to determine the most efficient extracting solvent. The total phenol content was measured by the Folin–Ciocalteu method and expressed as phloroglucinol equivalents (PGE). The antioxidant tests used were 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, linoleic acid-β carotene oxidation inhibiting assay, and Fe2+ ion chelating method. Higher phenolic contents were obtained using aqueous organic solvents, as compared to the respective absolute solvents; 70 % acetone was found to be the most efficient solvent (1.039 mg PGE 100 mg?1 dry algal powder). High significant correlations were noted between total phenol content and the tested antioxidant activities; so the aqueous organic extracts exhibited the highest antioxidant activities versus DPPH radicals (EC50 values of 0.6–1.1 mg dry weight (DW) mL?1), linoleic acid-β carotene oxidation (74–78 % at 0.8 mg DW mL?1), as well as ferrous ions (EC50 values of 5.0–7.9 mg DW mL?1). Some methodological recommendations regarding the assays used and the expression of results are proposed.  相似文献   

9.
Salacia chinensis L. has various beneficial properties including antidiabetic and antioxidant activity. The S. chinensis fruit pulp (SCFP) was extracted with four different solvents (Methanol, ethanol, acetone and water) and was screened for total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activity (AOA). The AOA was assessed by evaluating the 1, 1-diphenyl-2-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and metal chelating assay. Methanolic SCFP extract exhibited the highest phenolic content (3.20?±?0.12 mg GAE/g FW) whereas, ethanolic extract showed highest flavonoid content (0.31?±?0.68 mg RE/g FW). The methanolic extract possesses highest antioxidant activity towards DPPH (92.44 %), FRAP (1.939 O.D) and metal chelating activity (74.16 %). AOA (DPPH and FRAP) was significantly correlated with TPC. The results indicated that SCFP is a good natural source of antioxidant compounds for use in food and pharmaceutical industry.  相似文献   

10.
以菠萝22个栽培品种的叶片为实验材料,测定其5种色泽参数(L*、a*、b*、c*和h*值)、5种色素(叶绿素、类胡萝卜素、花青苷、类黄酮和总酚)含量及3种抗氧化活性指标(ABTS、DPPH自由基和亚硝酸盐的清除能力),并进行相关性分析。研究结果显示,色泽参数a*和h*值可以作为菠萝叶片指示色泽、主要色素含量和抗氧化活性变化的重要指标;菠萝叶片主要色素组成是叶绿素、类黄酮和总酚,且含有少量的花青苷,几乎不含类胡萝卜素。相关性分析结果显示,菠萝叶片类黄酮和总酚含量均与3种抗氧化活性指标极显著正相关,而叶绿素含量与其它指标相关性未达到显著水平,类黄酮和总酚是菠萝叶片抗氧化活性的主要功效成分。  相似文献   

11.
The current study used RP-HPLC to compare phytochemicals and estimate the bioactive constituents found in Stevia rebaudiana Bert. (SRB) leaves collected from two different geographical sources. SRB leaves were collected from Bangalore, Karnataka, India, and Reduit, Mauritius. Extracts were prepared using ethanol and aqueous solvents. Proximate analysis was used to evaluate moisture content, ash values, crude fibers, and extractive values. Following that, preliminary phytochemical screening was done on both ethanol leaves extracts, and subsequently total flavonoid content was determined. In addition, TLC chromatograms and RP-HPLC studies were performed on both plant extracts to determine the presence of flavonoid components in both leaves extracts, followed by in vitro anti-diabetic activity was performed with alpha amylase and alpha glucosidase enzymes against Acarbose as standard. Results revealed that both the extracts from two different geographical sources varied significantly with the yield, content of chemicals, and presence of quercetin (flavonoid) content when estimated through the RP-HPLC standardized method. Glycosides, flavonoids, proteins, steroids, saponins, terpenoids, and phenols were found in various concentrations during phytochemical screening. Among both zones, the ethanol leaves extract of SRB taken from Mauritius had a greater content of phytochemicals and a higher yield than other extracts due to the soil nature. The Mauritius sample had greater total flavonoid levels as well as more quercetin (0.92 ± 0.011) than the other extracts. Following that, ethanol extract inhibited enzymes (alpha amylase, alpha glucosidases) more than aqueous extract, and this inhibition was dose dependent. Among them, the Mauritius ethanol sample showed higher anti-diabetic efficacy than the Indian sample, but this difference was not significant. Overall, SRB ethanol leaves extracts outperformed other leaves extracts in terms of yield, phytoconstituents, and total flavonoids. Overall, both SRB samples had high quercetin levels and possessed anti-diabetic potential, but they were greater in the Mauritius sample, demonstrating that plant traits are influenced by geographic location.  相似文献   

12.
葛根中总黄酮的提取条件优化及含量测定   总被引:1,自引:0,他引:1  
采用乙醇浸提法对葛根黄酮提取工艺进行研究,考察了提取温度、时间、乙醇浓度及固液比对葛根黄酮收率的影响,通过正交试验确定了葛根黄酮提取的最佳工艺条件,并采用紫外分光光光度法,以葛根素标准溶液为标样,测定了葛根中总黄酮的含量。实验结果表明,提取温度为70℃,固液比控制在1∶20,乙醇体积分数为80%,提取120min,葛根黄酮得率高达3.3%。在葛根黄酮检测方法的方法学考察中,平均回收率为97.5%,标准差与变异系数均较小,表明该测定方法精密度高,重现性好,可作为检测葛根中总黄酮含量的一种有效手段。  相似文献   

13.
In vitro antimicrobial activity of 21 crude extracts obtained from seven taxa of the genus Teucrium (T. chamaedrys, T. montanum, T. arduini, T. polium, T. scordium subsp. scordium, T. scordium subsp. scordioides and T. botrys) was tested against bacterial and fungal species. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined using a microdilution analysis method. Total phenolic content and flavonoid concentrations were measured spectrophotometrically. Total phenols were determined using Folin-Ciocalteu reagent and their amounts ranged from 28.49 up to 159.84 mg CA/g of extract (chlorogenic acid equivalent). The amounts of flavonoids ranged from 38.17 up to 190.45 mg RU/g of extract (rutin equivalent).The plant extracts showed greater potential of antibacterial than antifungal activity. A relationship was found between total phenolics and biological activity. The highest level of total phenols was measured in the methanol extracts, which demonstrated higher antimicrobial activity than acetone and ethyl acetate extracts. Staphylococcus aureus ATCC 25923 appeared to be the most sensitive organism. Our results indicate that Teucrium spp extracts are rich sources of phenolic compounds and are promising candidates for further development as natural antimicrobial agents.  相似文献   

14.
通过单因素试验、响应面分析法优化牡丹根皮的总黄酮提取工艺,并用紫外分光光度法测定不同产地野生和栽培牡丹皮总黄酮含量。结果显示,最佳工艺为料液比1:50 (g/mL),乙醇浓度50%,提取温度64 ℃,超声时间65 min,陕西商洛和陕西略阳产野生牡丹皮的总黄酮含量最高达64.035 mg·g-1,云南昆明栽培牡丹皮总黄酮含量最低,仅30.439 mg·g-1。  相似文献   

15.
This paper reports a comparative study based on the antioxidant compounds, total phenol content and antioxidant activities of leaves, stems and fruits from the main Tunisian cultivars, ‘chetoui’ and ‘chemchali’, grown in two different locations, north and south of Tunisia. The repartition of olive phenolic compounds was organ dependant. Therefore, the HPLC analysis indicated that the olive organs from the northern cultivar had the highest level of hydroxybenzoic acids, hydroxycinnamic acids and flavonoid class; which were less in the southern cultivar. Principal component analysis of the phenolic compounds showed discrimination between methanol extracts of the organs olive. Significant differences (p < 0.05) in the levels of phenols, orthodiphenols and flavonoids were found between cultivars and between organs. Antioxidant activities of the methanolic extract from aerial parts of the two studied cultivars were evaluated using 2,2-diphenyl-1-picrylhydrazyl and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) assays. In all tests, methanolic extracts of different olive parts showed higher antioxidant activity. These results can be used to discriminate and to characterize the ‘chetoui’ and ‘chemchali’ aerial parts.  相似文献   

16.
本研究通过测定人工段木栽培3年生杨树桑黄Sanghuangporus vaninii、鲍姆桑黄S. baumii、桑树桑黄S. sanghuang及野生桑树桑黄子实体的粗蛋白质、粗脂肪、粗纤维、氨基酸、多糖、三萜、总黄酮、总酚含量和抗氧化活性(ABTS和FRAP),探究此3种栽培桑黄及野生桑树桑黄子实体的营养、药效成分及抗氧化活性差异。结果表明,供试材料在营养、药效成分及抗氧化活性上差异较大。其中,栽培鲍姆桑黄子实体粗纤维含量最低,多糖含量较高,总黄酮、总酚含量和ABTS、FRAP活性最高;栽培杨树桑黄粗纤维含量较低,粗脂肪含量最低,总黄酮、总酚、三萜含量较高,多糖含量最高;野生桑树桑黄粗蛋白、粗脂肪、总氨基酸含量最高,多糖含量较高,三萜含量最高,总黄酮、总酚含量和ABTS、FRAP活性最低;栽培桑树桑黄粗纤维含量较高,多糖、总黄酮、总酚、三萜含量和ABTS、FRAP均较低。栽培杨树桑黄、鲍姆桑黄和野生桑树桑黄在药效成分含量上各有所长。筛选到可结实、药效成分含量高的桑树桑黄菌株是可能的。桑黄优良品种选育是今后的工作重点。本研究为桑黄真菌资源开发利用提供了参考。  相似文献   

17.
Enzymatic synthesis of acylated derivatives of a monosaccharidic flavonoid chrysoeriol-7-O-beta-D-(3'-E-p-coumaroyl)-glucopyranoside as well as of a disaccharidic flavonoid chrysoeriol-7-[6'-O-acetyl-beta-D-allosyl-(1-->2)-beta-D-glucopyranoside], isolated from Greek endemic plants, was performed using an immobilized Candida antarctica lipase in non-toxic organic solvents. The influence of the reaction parameters such as the molar ratio of acyl donor to flavonoid, as well as the nature of the acyl donor, on the performance of the biocatalytic process was pointed out using the acylation of naringin as a model reaction. With vinyl laurate as acyl donor, the highest conversion was observed at relatively high molar ratio (>or=10), using acetone as solvent. Lipase exhibits specificity towards primary alcohol of the glucose moiety of both flavonoid glycosides. The introduction of an acyl group into glucosylated flavonoids significantly improved their antioxidant activity towards both LDL and serum model in vitro. Furthermore, the acylated derivative of disaccharidic flavonoid increased its antimicrobial activity against two Gram-positive bacteria.  相似文献   

18.
There is increasing interest in the emerging view that tea improves the antioxidant status in vivo and thereby helps to lower risk of certain types of cancer, coronary heart disease and stroke and its component biofactors could provide prophylactic potential for these diseases. The polyphenolic composition and the antioxidant properties of organic extracts (acetone/methanol) of Mauritian commercial black teas were evaluated. HPLC data of the individual compounds revealed remarkably high levels (+)-Catechin ((+)-C), (-)-epicatechin ((-)-EC), (-)-epicatechin 3-gallate ((-)-ECG), (-)-epigallocatechin ((-)-EGC), (-)-epigallocatechin 3-gallate ((-)-EGCG) and gallic acid. Analysis of hydrolysed extracts indicated that quercetin was the dominant flavonol aglycone with traces of myricetin and kaempferol. Based on the Ferric Reducing Antioxidant Power (FRAP) and the Trolox Equivalent Antioxidant Capacity (TEAC) assays Extra tea from Bois Chéri exhibited the highest antioxidant potential. Linear regression analyses showed that the antioxidant capacities of the organic extracts are strongly influenced by total phenols (TEAC: r=0.95 and FRAP: r=0.96) and to a lesser extent by total proanthocyanidin and total flavonoid contents. Catechins and gallic acid seem to add up to the overall antioxidant capacity of black tea extracts. The fresh tea leaves had high levels of total phenols, total flavonoids, total proanthocyanidin and exhibited greater antioxidant potential when compared with black teas. Organic extracts of endemic teas represent useful source of phenolic antioxidants supplements for prophylactic use.  相似文献   

19.
该研究以幼果期、白果期、转色期的离体‘北陆’蓝莓果实为试材,设置0(CK)、5、10、15min紫外光辐照处理,24h后取样分析蓝莓果实中可溶性糖、总酚、类黄酮和花青苷含量,以及苯丙氨酸裂解酶(PAL)和查尔酮异构酶(CHI)活性的变化,探究UV-B紫外照射处理对不同发育时期蓝莓主要果实品质及相关酶活的影响。结果显示:(1)对于幼果期蓝莓,5min UV-B处理可显著增加果实内可溶性糖含量;10min UV-B处理果实PAL活性增加效果最为显著;15min UV-B处理对果实总酚和花青苷积累的促进作用最大,但显著降低了类黄酮含量和CHI活性。(2)对于白果期蓝莓,5min UV-B处理显著增加了果实类黄酮含量和CHI活性,10min处理使果实可溶性糖和总酚含量较对照分别增加25%和18%;15min处理对果实花青苷含量和PAL活性影响作用最大。(3)对于转色期蓝莓,各处理除果实可溶性糖及类黄酮含量降低外,其余物质含量均显著增加。(4)UV-B处理并未改变果实发育过程中可溶性糖、总酚、类黄酮和花青苷含量及PAL、CHI酶活性的积累规律。(5)蓝莓果内PAL活性与其可溶性糖、总酚和类黄酮的积累呈极显著正相关关系,而CHI活性仅与其可溶性糖呈极显著正相关。研究表明,UV-B辐照处理促进了幼果期和白果期可溶性糖的积累,也能促进不同发育时期蓝莓果实总酚和花青苷及白果期类黄酮的积累,对蓝莓果实主要品质能够产生积极的影响。  相似文献   

20.
Detoxification of olive mill wastewaters by Moroccan yeast isolates   总被引:1,自引:0,他引:1  
A total of 105 yeast strains were isolated from Moroccan olive oil production plants and evaluated for their ability to grow in olive oil mill wastewaters (OMW). The 9 isolates that grew best on OMW were selected for further study to evaluate their effect on removal of organic pollutants and OMW phytotoxicity (barley seed germination test). The results showed that at least four yeast isolates effectively lowered the toxicity of this effluent in addition to providing very useful materials in terms of both yeast biomass (6 g/l DW) and an irrigation fluid. This group of yeast isolates significantly reduced the concentration of total phenols (44% removal) and Chemical Oxygen Demand, COD (63% removal). The best germination rate of 80% for undiluted OMW was obtained for strain Candida holstii that also increased the pH from 4.76 to 6.75. Principal component analysis of the results obtained for the best yeast strains confirmed the importance of COD and total phenol reduction along with increase of organic nitrogen and final pH for the improvement of germination rates and phytotoxic reduction. This study has highlighted the potential of indigenous yeasts in detoxification of olive mill wastewaters.  相似文献   

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