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1.
Some Viburnum species are used for preparation of the traditional drink called gilaburu in Anatolia. In the current study, our goal was to evaluate acetylcholinesterase (AChE) inhibitory and antioxidant activities of the ethyl acetate, methanol, and water extracts prepared from the branches, leaves, and fruits of Viburnum opulus and Viburnum lantana along with salicin, amentoflavone, and chlorogenic acid, three major compounds abundantly found in these species. AChE enzyme inhibition was tested in vitro using an enzyme-linked immunosorbent assay microplate reader at 50, 100, and 200?μL/mL concentrations. Antioxidant activity was examined by ferrous ion chelating capacity, ferric reducing antioxidant power, and β-carotene bleaching assay at 500, 1,000, and 2,000?μg/mL. Total phenol and flavonoid contents of the extracts were also established by Folin-Ciocalteau and AlCl(3) reagents, respectively. Our data revealed that the leaf methanol extract of V. opulus displayed a significantly high inhibitory effect against AChE (57.63?±?1.23%, 87.41?±?0.99%, and 93.19?±?0.87% at 50, 100, and 200?μg/mL, respectively). The extracts of V. lantana exerted higher antioxidant activity.  相似文献   

2.
目的研究石榴籽提取物的体外抗氧化作用。方法采用普鲁士蓝法、邻二氮菲-Fe2+氧化法和邻苯三酚自氧化法分别测定石榴籽提取物的总抗氧化能力、石榴籽提取物对羟自由基(.OH)和超氧阴离子(.O2-)的清除作用,并与维生素C抗氧化活性相比较。结果石榴籽提取物对.OH和.O2-具有很强的清除作用,其IC50分别为0.157和0.027mg/ml,与维生素C抗氧化作用相似。结论石榴籽提取物具有较强的清除自由基能力,是一种天然有效的抗氧化剂。  相似文献   

3.
Water and ethanol crude extracts from black pepper (Piper nigrum) were investigated for their antioxidant and radical scavenging activities in six different assay, namely, total antioxidant activity, reducing power, 1,1-Diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, and metal chelating activities. Both water extract (WEBP) and ethanol extract (EEBP) of black pepper exhibited strong total antioxidant activity. The 75 microg/ml concentration of WEBP and EEBP showed 95.5% and 93.3% inhibition on peroxidation of linoleic acid emulsion, respectively. On the other hand, at the same concentration, standard antioxidants such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and alpha-tocopherol exhibited 92.1%, 95.0%, and 70.4% inhibition on peroxidation of linoleic acid emulsion, respectively. Also, total phenolic content in both WEBP and EEBP were determined as gallic acid equivalents. The total phenolics content of water and ethanol extracts were determined by the Folin-Ciocalteu procedure and 54.3 and 42.8 microg gallic acid equivalent of phenols was detected in 1 mg WEBP and EEBP.  相似文献   

4.
荞麦蛋白和类黄酮提取物清除自由基的ESR研究   总被引:6,自引:0,他引:6  
目的:探讨荞麦蛋白质提取物(BWPr)和类黄酮提取物(BWF)清除活性氧自由基的作用。方法:采用电子自旋共振(ESR)及自旋捕获技术。结果:BWPr可清除O2,且呈明显的量效关系,在1.4~_?6.0mg/ml浓度范围内,随着蛋白液浓度的增加,清除率近乎直线升高,而再增加蛋白液的浓度,清除率增加幅度下降,甜荞蛋白和苦荞蛋白的IC50分别为4.1mg/ml、3.2mg/ml。而BWF清除O2的作用高于_?甜荞蛋白和苦荞蛋白,当其浓度为58mg/L时清除率就达77.89%,而浓度为293mg/L时清除率达到98.56%。BWPr对·OH也有一定的清除效果,但不及BWF。结论:BWPr和BWF都有清除活性氧自由基的作用,提示除荞麦类黄酮外,荞麦蛋白质也是一种自由基清除剂。  相似文献   

5.
Water and ethanol crude extracts from black pepper (Piper nigrum) were investigated for their antioxidant and radical scavenging activities in six different assay, namely, total antioxidant activity, reducing power, 1,1-Diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, and metal chelating activities. Both water extract (WEBP) and ethanol extract (EEBP) of black pepper exhibited strong total antioxidant activity. The 75?µg/ml concentration of WEBP and EEBP showed 95.5% and 93.3% inhibition on peroxidation of linoleic acid emulsion, respectively. On the other hand, at the same concentration, standard antioxidants such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and α-tocopherol exhibited 92.1%, 95.0%, and 70.4% inhibition on peroxidation of linoleic acid emulsion, respectively. Also, total phenolic content in both WEBP and EEBP were determined as gallic acid equivalents. The total phenolics content of water and ethanol extracts were determined by the Folin-Ciocalteu procedure and 54.3 and 42.8?µg gallic acid equivalent of phenols was detected in 1?mg WEBP and EEBP.  相似文献   

6.
The phenolic contents of methanolic extracts of emblica (Phyllanthus emblica L.) fruit from six regions in China were measured in this work. The antioxidant activities of these extracts were also evaluated. Total phenolic content was ranged from 81.5 to 120.9 mg gallic acid equivalents (GAE)/g and the flavonoid content was varied from 20.3 to 38.7 mg quecetin equivalents (QE)/g, while proanthocyanidin content was ranged from 3.7 to 18.7 mg catechin equivalents (CE)/g. Among all the methanolic extracts analyzed, the Huizhou sample exhibited a significantly higher phenolic content than other samples (P<0.05). The antioxidant activities were evaluated by in vitro experiments using scavenging assays of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, hydroxyl radicals, and superoxide anion radicals, chelating ability of ferrous ion, reducing power, and inhibition capability of Fe (II)-induced lipid peroxidation, respectively. The Huizhou sample was found to have the strongest antioxidant activities in scavenging DPPH radicals, superoxide anion radicals, and had the highest reducing power, while the Chuxiong sample showed the best performance in chelating iron and inhibiting lipid peroxidation. Furthermore, the Chuxiong sample exhibited a stronger inhibition activity of the hydroxyl radicals compared with other samples. The high correlation coefficient was existed between the phenolic content and superoxide anion radical scavenging activity, but no significant correlation was found between the former and hydroxyl radical scavenging activity. Methanolic extracts of emblica fruit from some selected regions exhibited stronger antioxidant activities compared to those of the commercial compounds (quercetin and BHA). It might be considered as a potential plant source of antioxidants.  相似文献   

7.
目的:以柑橘皮为原料,利用甲醇为溶剂,采用浸提法从柑橘皮提取生物活性物质总黄酮,通过体外实验评价柑橘皮总黄酮的抗氧化活性,以提高柑橘资源的开发利用效率。方法:通过单因素实验和正交实验确定柑橘皮总黄酮的最佳提取工艺条件。以芦丁为对照,体外测定柑橘皮总黄酮提取物对超氧阴离子自由基(O-2.)、羟自由基(.OH)及二苯代苦味酰基苯肼(DPPH.)自由基的清除率。结果:以甲醇为溶剂提取柑橘皮总黄酮的最佳提取工艺条件为:料液比1:30、溶剂浓度70%、温度60℃、浸提时间4 h的提取条件下,总黄酮产量为4.96%。体外抗氧化活性研究结果表明,柑橘皮总黄酮具有较高的自由基清除能力,其清除效果随提取物浓度的增加而增强。柑橘皮总黄酮对O-2.和DPPH.自由基的清除率高于芦丁,而对于.OH自由基的清除率比芦丁稍低。结论:柑橘皮总黄酮具有明显的抗氧化能力,为综合开发利用柑橘资源提供了科学依据。  相似文献   

8.
The aims of this study are to determine and compare the antioxidant levels and activities (i.e. primary and secondary) between selected seeds of Malaysian tropical fruits - guava (Psidium guajava), mango (Mangifera indica L.) and papaya (Carica papaya L.). Seeds are among byproducts from the processing of fruitsbased products. Instead of discarding seeds as waste, seeds with high potential as antioxidants could be utilised for commercial purposes. Accordingly, the selected seeds of Malaysian tropical fruits were tested in this study for total phenolic content (TPC), free radical scavenging activity by 1, 1- diphenyl-2-picrylhydrazyl (DPPH) assay and metal ion chelating effect by ferrous ion chelating (FIC) assay. Extraction of antioxidant compounds from sample was done with 70% ethanol. TPCs of the seeds were expressed as gallic acid equivalents (GAE) in mg per 100 g fresh seed weight. TPC assay showed that mango seeds had the highest TPC (i.e. 32 ± 0.001 mg GAE) followed by guava seeds (i.e. 20 ± 0.001 mg GAE) and papaya seeds (8 ± 0.003 mg GAE). For DPPH assay, IC50 data showed that mango seed extract scavenged 50% DPPH radicals at the lowest concentration (0.11 ± 0.01 mg/mL) followed by the positive control BHA (0.13 ± 0.01 mg/mL), guava seed extract (0.26 ± 0.01 mg/mL) and papaya seed extract (0.34 ± 0.01 mg/mL). Interestingly, all seed extracts showed higher free radical scavenging activities than BHA after sample concentration of 0.60 mg/mL. However, FIC assay indicated that metal ion chelating effects of all seed extracts were weaker than BHA suggesting that the fruit seeds are not sources of good metal ion chelators. Overall, present results suggest that TPC of the seeds show strong negative correlation with their primary antioxidant activity (r= -0.985, R2= 0.970), and not all compounds in extracts which could scavenge DPPH radicals are good metal ion chelators. Mango seeds relatively showed the highest antioxidant level and primary antioxidant activity followed by guava seeds and papaya seeds.  相似文献   

9.
葡多酚对活性氧自由基的清除作用研究   总被引:26,自引:2,他引:24  
王传现  钟进义 《营养学报》2001,23(2):170-173
目的 : 探讨葡多酚 ( GPC)对活性氧自由基的清除作用。方法 : 采用电子自旋共振 ( ESR)和自旋捕集技术直接测定不同浓度 GPC对 Fenton反应体系产生的羟自由基 (· OH)、光照核黄素 /EDTA体系产生的超氧阴离子 ( O·2 )及 Fe2 + 启动线粒体膜脂质过氧化产生的脂类自由基 ( LOO· )清除作用。结果 :  GPC浓度为 1 mg/L、1 0 mg/L、1 0 0 mg/L、1 0 0 0 mg/L对·OH的清除率 ( % )依次为 9.0、2 0 .6、47.7、57.7,对 O·2 的清除率 ( % )分别为 1 0 .9、1 7.0、50 .9、72 .1 ,对LOO·的清除率 ( % )依次为 39.8、49.6、65.9、71 .4。葡多酚对· OH、O·2 及 LOO· 50 %的清除浓度 ( IC50 值 )分别为 1 2 8.9mg/L、89.4mg/L、1 0 .4mg/L。结论 : 葡多酚对三种活性氧自由基均有不同程度的清除作用 ,其中 LOO· >O·2 >· OH。  相似文献   

10.
Chitosan (CS) with two different molecular weights was modified by reacting with 4-hydroxyl-5-chloride-1,3-benzene-disulfo-chloride or 2-hydroxyl-5-chloride-1,3-benzene-disulfo-chloride to give new 2-(4(or 2)-hydroxyl-5-chloride-1,3-benzene-di-sulfanimide)-chitosan (2-HCBSAHCS, 2-HCBSALCS, 4-HCBSAHCS, 4-HCBSALCS). The structure of the derivatives was characterized by FT-IR and 13C NMR spectroscopy. The antioxidant activities of the derivatives were investigated employing various established systems, such as hydroxyl radical (.OH)/superoxide anion (O2.-) scavenging/reducing power and chelating activity. All the derivatives showed stronger scavenging activity on hydroxyl radical than chitosan and ascorbic acid (Vc), and IC50 of 4-HCBSAHCS, 4-HCBSALCS, 2-HCBSAHCS and 2-HCBSALCS was 0.334, 0.302, 0.442, 0.346 mg/mL, respectively. The inhibitory activities of the derivatives toward superoxide radical by the PMS-NADH system were strong. The results showed that the superoxide radical scavenging effect of 2-(4(or 2)-hydroxyl-5-chloride-1,3-benzene-di-sulfanimide)-chitosan was higher than chitosan. The derivatives had obviously reducing power and slight chelating activity. The data obtained in in vitro models clearly establish the antioxidant potency of 2-(4(or 2)-hydroxyl-5-chloride-1,3-benzene-disulfanimide)-chitosan.  相似文献   

11.
Herbs and spices not only variety and racy flavour to Korean foods, they also are the richest source for antioxidant power. The present study evaluates the radical scavenging-linked antioxidant activities of hot water extracts from commonly used herbs and spices in Korea. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical and superoxide anion scavenging activities of bay extract were 39.5% and 22.1%, respectively. The hydroxyl radical scavenging activity was in order of dill (50.0%) > bay (31.3%) > garlic (27.9%) > white pepper and black pepper (15.1-15.3%) > onion (10.1%) extracts. Bay extract had the highest total phenolic content (17.86?μg CE/g). High correlation coefficients were found between the total phenol content and DPPH radical scavenging activity (R?=?0.9162). These results indicate that herbs and spices had high antioxidant activity that is partly due to the phenolic compounds and provide basic data for further development of processed food products.  相似文献   

12.
The stem, leaf, and root of Tinospora cordifolia (willd.) have been highly exploited for medicinal preparations; however, the nutritional and nutraceutical potential of its attractive red berries (fruits) have not so far been studied. Pigments, berberine (107.0 mg/100 g) and lycopene (50.8 mg/100 g), were identified in the deseeded fruit. Total phenol content in the fruit was 3.2 mg gallic acid equivalent/g. The IC(50) of DPPH· (82, and 468 ppm) and OH· (100, and 1,000 ppm) scavenging activity, and the EC(50) of reducing power (2,616, and 1,472 ppm) of hexane and methanol extracts, respectively, were observed. Oxygen radical absorbance capacities of the fruit extracts (150 and 300 ppm) were 1,107 and 2,614 μM trolox equivalent/g, respectively. Nutrient composition including carbohydrate (18.4%), proteins (1.5%), lipids (6%) of which ~62% was unsaturated fatty acids, vitamins like ascorbic acid (0.24 μg), niacin (0.7 mg), and tocopherols (2.4 mg) in 100 g fruits were determined. Potassium content was 1.2 g/100 g dry tissue of berries. These findings show that components of T. cordifolia fruit could be bioactive and used in food, pharmaceutical, and cosmetics.  相似文献   

13.
The antioxidant activities of methanolic extracts of far-infrared irradiated rice hull (FRH) and non-irradiated intact rice hull (IRH) were determined. The antioxidant effects against reactive oxygen species (ROS) were evaluated by measuring scavenging activities against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, superoxide, hydrogen peroxide (H2O2), and nitric oxide radical and capacity for chelating metals. Except for H2O2 scavenging activity, FRH showed higher scavenging activity than IRH; for example, the 50% inhibitory concentration (mg/mL) values for DPPH radical scavenging of FRH and IRH were 0.067 and 0.085, respectively, as compared with 0.362 and 0.012 for butylated hydroxytoluene and alpha-tocopherol, respectively. The effect of rice hull extract on DNA damage induced by H2O2 in human lymphocytes was also evaluated by comet assay. The protective effect of rice hull extract increased as its concentration increased from 12.5 to 50 microg/mL, as indicated by DNA strand breakage decreasing from 38% to 22% with FRH and from 49% to 28% with IRH as compared with H2O2-treated positive controls. When human lymphocytes were post-incubated with rice hull extract for 30 minutes after exposure to H2O2, the protective ability of the rice hulls remained unchanged. These results suggest that methanol extracts of rice hulls possess significant ROS scavenging and metal chelating activities and protective effect against oxidative DNA damage.  相似文献   

14.
Glycoprotein from Solanum nigrum L. (SNL glycoprotein) was isolated and tested for antioxidative effects on oxygen free radicals using a 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. The free radical scavenging activities of the SNL glycoprotein are optimal in acidic pH and up to 60 degrees C. However, it has minimal activities in the presence of EDTA, although such activities are not dependent on M(2+) ions (Ca(2+), Mn(2+), and Mg(2+)) in the presence of EDTA. Interestingly, when SNL glycoprotein was treated with deactivation agents (pronase E and NaIO(4)), the DPPH radical scavenging activity was decreased compared with the SNL glycoprotein treatment alone. The antioxidative effects of SNL glycoprotein on superoxide anion and hydroxyl radical under optimal conditions revealed that SNL glycoprotein has remarkable scavenging effects on both radicals, but exhibited slightly higher scavenging effects on superoxide anion generated by the enzymatic hypoxanthine/xanthine oxidase system than on hydroxyl radicals generated by the Fenton reaction. However, SNL glycoprotein was more effective against hydroxyl radials in cell cultures (NIH/3T3). Consequently, 20 microg/mL SNL glycoprotein has a scavenging ability against superoxide anion corresponding to that of ascorbic acid. On the other hand, its hydroxyl radical scavenging activity corresponds to 0.1 microg/mL catalase. From these results, we suggest that SNL glycoprotein has potent antioxidative potential.  相似文献   

15.
光皮木瓜多酚类的提取和清除DPPH的抗氧化活性   总被引:15,自引:0,他引:15  
张婷  糜漫天  唐勇  赵靖 《营养学报》2007,29(5):485-489
目的:从光皮木瓜中提取多酚类物质,分析其成分含量并测定其多酚的抗氧化活性。方法:将光皮木瓜分为水提物和醇提物两部分,采用纤维素酶解方法处理原料,进行对比实验。在实验中以分光光度法测定其总多酚、单宁和黄酮类含量;薄层色谱定性分析其单体成分;DPPH自由基清除实验测定其抗氧化性能。结果:光皮木瓜提取物中的总多酚为1801mg/100gFW,其中单宁935mg/100gFW,黄酮类294mg/100gFW,酶解有助于多酚含量的提高(P<0.05);薄层色谱的定性分析显示含有儿茶素单体和绿原酸;DPPH自由基清除效应实验结果指出水提物清除自由基的活性较醇提物强,而且酶解后各部分的活性均增强。结论:光皮木瓜提取物中的多酚类物质含量较高并有较强的抗氧化活性。  相似文献   

16.
Herbs and spices not only variety and racy flavour to Korean foods, they also are the richest source for antioxidant power. The present study evaluates the radical scavenging-linked antioxidant activities of hot water extracts from commonly used herbs and spices in Korea. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical and superoxide anion scavenging activities of bay extract were 39.5% and 22.1%, respectively. The hydroxyl radical scavenging activity was in order of dill (50.0%) > bay (31.3%) > garlic (27.9%) > white pepper and black pepper (15.1–15.3%) > onion (10.1%) extracts. Bay extract had the highest total phenolic content (17.86 μg CE/g). High correlation coefficients were found between the total phenol content and DPPH radical scavenging activity (R = 0.9162). These results indicate that herbs and spices had high antioxidant activity that is partly due to the phenolic compounds and provide basic data for further development of processed food products.  相似文献   

17.
目的研究三种蛋白酶的蛋清蛋白酶解物(EWPH)的抗氧化及血管紧张素转换酶(ACE)抑制活性。方法分别采用Fenton体系、邻苯三酚自氧化体系和亚油酸自氧化体系测定胰蛋白酶、木瓜蛋白酶及alcalase碱性蛋白酶的EWPH清除羟自由基、超氧阴离子及抑制脂质过氧化的能力。利用高效液相色谱法测定ACE抑制活性。超滤分离上述三种蛋白酶的EWPH,检测各组分的抗氧化和ACE抑制活性。结果抗氧化活性最强的是木瓜蛋白酶的EWPH,在浓度10mg/ml时,对羟自由基和超氧阴离子清除率分别为53.14%和27.87%,在浓度0.8mg/ml时,对亚油酸自氧化的抑制率73.72%(D7)。ACE抑制效果最明显的是胰蛋白酶的EWPH,其IC50值为0.985mg/ml。低分子量(Mw3ku)组分酶解物的活性优于高分子量(Mw3ku)组分。结论三种蛋白酶的EWPHs均具有抗氧化和ACE抑制活性,但两种活性之间无明显的相关,且小分子组分的活性最强。  相似文献   

18.
The aromatic herb Melissa officinalis L. can be used as an easily accessible source of natural antioxidants and as a possible food supplement and as a phytochemical. Radical scavenging, antibacterial, and antiproliferative activities of petroleum ether, chloroform, ethyl acetate, n-butanol, and water extracts of M. officinalis L. extracts were investigated. The results of antioxidative activity, obtained by electron spin resonance spectroscopy, confirmed that investigated extracts suppressed the formation of 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl, and lipid peroxyl radicals in all investigated systems in a dose-dependent manner. The maximum DPPH and hydroxyl radical scavenging activities (SA(DPPH) = SA(OH) = 100%) were achieved in the presence of n-butanol extract at concentrations of 0.4 mg/mL and 0.5 mg/mL, respectively. The highest lipid peroxyl scavenging activity (93.20%) was observed at a higher concentration (5 mg/mL) of n-butanol extract in the lipid peroxidation system. The most effective antibacterial activities were expressed by petroleum ether and ethyl acetate extracts on Sarcina lutea. Chloroform extract showed the strongest antiproliferative effect with 50% inhibitory concentration values of 0.09 mg/mL and 0.10 mg/mL for HeLa and MCF-7 cell lines, respectively. The present study demonstrated the high phenolic content and radical scavenging, antibacterial, and antiproliferative activities of extracts of M. officinalis L. originating from Serbia.  相似文献   

19.
Antioxidant properties of brown seaweed (Sargassum siliquastrum) extracts were evaluated using various antioxidant measurements, i.e., inhibitory effect on thiobarbituric acid-reactive substances (TBARS), 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, metal chelating effect, reducing power effect, and total phenolic compounds. When the extraction solvents n-hexane, chloroform, ethanol, and water were compared, the water extract showed the highest yield in extracted mass. Total phenolic compounds were the highest in the ethanol extract, with 127.4 mg/g. The TBARS inhibition of chloroform and ethanol extracts at 10 mg/mL was 90.9% and 80.9%, respectively. DPPH radical scavenging capacity was more than 90% in all extracts at 1 mg/mL. The chloroform extract exhibited the highest metal ion chelating ability of 69.6% at 10 mg/mL. The reducing power was found to be the highest in the ethanol extract at 10 mg/mL, showing an effect similar to ascorbic acid. Thus, the ethanol extract of S. siliquastrum has potential as a natural antioxidant.  相似文献   

20.
Several extracts of the leaves and fruits of Juglans regia L. were assessed for their neuroprotective effects through antioxidant and anti-cholinesterase methods. Anticholinesterase activity was determined against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), the enzymes vital for Alzheimer's disease, at 50, 100 and 200 μg ml(-1). Antioxidant activity was tested using radical scavenging activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH), N,N-dimethyl-p-phenylenediamine (DMPD), superoxide (SO), nitric oxide (NO) and hydrogen peroxide (H(2)O(2)) radicals, as well as ferric ion-chelating capacity, ferric- and phosphomolybdenum-reducing antioxidant power at 500, 1000 and 2000 μg ml(-1). Total phenol and flavonoid quantification of the extracts was calculated. The extracts scavenged DPPH radical in varying degrees; however, they did not scavenge DPMD and H(2)O(2). Only the dichloromethane and water extracts were able to quench SO (10.09 ± 1.38%) and NO (24.09 ± 2.19%) radicals, respectively, at low level. The extracts showed either low or no BChE inhibition and no AChE inhibition.  相似文献   

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