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1.
《Fitoterapia》2014
Silymarin, a standardised extract of Silybum marianum (milk thistle), comprises mainly of silybin, with dehydrosilybin (DHSB), quercetin, taxifolin, silychristin and a number of other compounds which are known to possess a range of salutary effects. Indeed, there is evidence for their role in reducing tumour growth, preventing liver toxicity, and protecting a number of organs against ischemic damage. The hepatoprotective effects of silymarin, especially in preventing Amanita and alcohol intoxication induced damage to the liver, are a well established fact. Likewise, there is weighty evidence that silymarin possesses antimicrobial and anticancer activities. Additionally, it has emerged that in animal models, silymarin can protect the heart, brain, liver and kidneys against ischemia reperfusion injury, probably by preconditioning. The mechanisms of preconditioning are, in general, well studied, especially in the heart. On the other hand, the mechanism by which silymarin protects the heart from ischemia remains largely unexplored. This review, therefore, focuses on evaluating existing studies on silymarin induced cardioprotection in the context of the established mechanisms of preconditioning. 相似文献
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Explants from seeds of Silybum marianum were used to produce either transformed ('hairy') or untransformed root cultures. Silybin, isosilybin, silychristin and silydianin were found in untransformed root cultures, by means of TLC and HPLC. In contrast, only isosilybin and traces of silychristin and silydianin were identified in the 'hairy' root cultures. 相似文献
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Velázquez E Tournier HA Mordujovich de Buschiazzo P Saavedra G Schinella GR 《Fitoterapia》2003,74(1-2):91-97
The antioxidant properties of six medical herbs used in the traditional Paraguayan medicine were studied using free radical-generating systems. The methanol extracts from Aristolochia giberti, Cecropia pachystachya, Eugenia uniflora, Piper fulvescens, Schinus weinmannifolia and Schinus terebinthifolia protected against enzymatic and non-enzymatic lipid peroxidation in microsomal membranes of rat. C. pachystachya, E. uniflora, S. weinmannifolia and S. terebinthifolia showed the highest scavenging activity on the superoxide and DPPH radicals. 相似文献
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A. Ahajji P. N. Diouf F. Aloui I. Elbakali D. Perrin A. Merlin B. George 《Wood Science and Technology》2009,43(1-2):69-83
Heat treatment of wood in absence of oxygen and under mild conditions allows for obtaining a material with many interesting properties, such as enhanced dimensional stability and increased biological durability. The aim of this work was to study the influence of a thermal treatment on the antioxidant activity of the extractives of two wood species – beech and spruce – by using the DPPH method and quantifying the formation of phenoxyl radicals using ESR as wood and extractives are exposed to light irradiation. The relationship between the kinetics of formation of free radicals in the extracts of heat-treated wood and the antioxidant properties is discussed. Links with colour modification are discussed. 相似文献
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Hydroalcoholic extracts of 10 medicinally used species collected from the area covered by a reservoir due to a dam built for the Salto Caxias Hydro-electric power plant in the State of Paraná, Southern Brazil, and Casearia sylvestris, were investigated for their potential antioxidant activity against DPPH (1,1-diphenyl-2-picrylhydrazyl) free radicals and by the phosphomolybdenum method. The extract of Bauhinia microstachya was found to be the most potent in both models. 相似文献
7.
Sheng-Yang?Wang Jyh-Horng?Wu Sen-Sung?Cheng Chiu-Ping?Lo Hsing-Ning?Chang Lie-Fen?Shyur Shang-Tzen?Chang
Calocedrus formosana Florin (Cupressaceae) is an endemic tree to Taiwan. To evaluate the antioxidant activity of the plant extracts from heartwood, bark, and leaf of C. formosana, assays for 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and superoxide anion scavenging activities, as well as prevention of DNA strand cleavage were performed in this study. Similar IC50 values against the DPPH radical were found for the heartwood and bark extracts at approximately 23µg/ml. Moreover, the heartwood extract exhibited the highest inhibitory activity against superoxide radicals among the test samples; a 2.3-fold lower value of IC50 for superoxide radical inhibition was found in the heartwood extract relative to that of (+)-catechin. Much less effect on inhibition of DPPH and superoxide radicals was found from the leaf extract of C. formosana. More than 70% of superoxide radicals were inhibited in the presence of 10µg/ml heartwood extract, whereas only 15% inhibition was obtained from the leaf extract. The heartwood extract, at a dose of approximately 0.5mg/ml, apparently completely prevented the X174 supercoiled DNA cleavage induced by ultraviolet photolysis of H2O2, as judged by agarose gel electrophoresis. This report also suggests that the antioxidant activities of the plant extracts of C. formosana are in good correlation with their phenolic contents. 相似文献
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花色苷(Anthocyanin)是植物多酚类化合物,广泛存在于自然界中。以笃斯越橘、黑加仑、树莓3种浆果为原料进行了花色苷抗氧化活性功能的研究,结果表明:3种花色苷都具有抗氧化活性,可以有效清除DPPH自由基、羟基自由基、超氧自由基,都具有还原能力,可以有效地抑制脂质过氧化。3种花色苷的抗氧化能力和其浓度之间存在着明显的量效关系,且在不同的抗氧化体系中相同浓度下的不同花色苷则表现出不同的抗氧化活性;3种方法相互之间对于测定花色苷抗氧化能力都具有显著的相关性。 相似文献
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北方主要越橘栽培品种果实品质及抗氧化能力的比较 总被引：1，自引：0，他引：1
以北方主要越橘栽培品种为材料,进行了果实品质、抗氧化物质及其能力的比较分析。结果表明,6个品种中北蓝（Northblue）果形最大,蓝丰（Bluecrop）果实总糖含量最高,美登（Blomidon）果实的可溶性固形物和总酸含量最高。越橘果实的主要抗氧化物质为花色苷、酚类和类黄酮化合物,其中,北蓝果实的花色苷和总黄酮含量最高,北陆（Northland）的多酚含量最高,伯克利（Berkeley）的花色苷、总黄酮和多酚含量均最低。通过总还原力、DPPH和清除超氧自由基的检测,蓝丰、北蓝、北陆的抗氧化能力较强,伯克利的抗氧化能力最弱。 相似文献
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Antioxidative effects of methanolic extracts from six wild European Lamiaceae species have been studied with the use of three in vitro assays. The ability of scavenging free radicals was measured by DPPH reduction spectrophotometric assay. The reducing potential towards transition metals was tested by phosphomolybdenum method and the inhibition of lipid oxidation was tested by Fe/ascorbate system with photometric TBARS detection. All studied herbs exposed strong antioxidant capability, but the results were different for each species depending on the applied test. In DPPH scavenging the order from strongest to the weakest was: Leonurus cardiaca, Lamium album, Marrubium vulgare, Stachys officinalis, Lamium purpureum, Galeopsis speciosa. With phosphomolybdenum method the extract of S. officinalis was the strongest in both 40 degrees Celsius and 90 degrees Celsius but other species acted differently in both temperatures. In lipid peroxidation assay, the maximum inhibition of 78% was reached by S. officinalis and M. vulgare, whereas for both Lamium sp. and L. cardiaca slightly exceeded 70% and for G. speciosa reached 65%. The observed differences indicate the complexity of involved mechanisms and support the necessity of combining several assays in studying the antioxidant potential of medicinal plants. 相似文献
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A new flavone glycoside, apigenin 5-O-alpha-L-rhamnopyranosyl-(1-->3)-beta-D-glucopyranoside (1), along with four known flavonol glycosides (2-5), were isolated from the leaf of Cephalotaxus koreana. The new glycoside 1 showed inhibitory activity in superoxide radical scavenging assay with IC(50) value of 13.0 microM, while it showed weak activity in 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging assay. Compounds 2-5 exhibited antioxidant activity in scavenging DPPH and superoxide radicals with IC(50) values ranging from 5.7 to 22.3 microM. 相似文献
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The present study was aimed to investigate the activity of Thai medicinal plants on inflammation caused by Propionibacterium acnes in terms of free radical scavenging and cytokine reducing properties. P. acnes have been recognized as pus-forming bacteria triggering an inflammation in acne. Antioxidant activity was determined by DPPH scavenging and NBT reduction assay. The result showed that Garcinia mangostana possessed the most significant antioxidant activity and reduced reactive oxygen species production. Houttuynia cordata, Eupatorium odoratum, and Senna alata had a moderate antioxidant effect. In addition, Garcinia mangostana extracts could reduce the TNF-alpha production as determined by ELISA. Garcinia mangostana was highly effective in scavenging free radicals and was able to suppress the production of pro-inflammatory cytokines. This study has identified the promising source of anti-inflammatory agent which could be useful in treatment of acne vulgaris. 相似文献
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Methanol extract of Rhaphidophora pertusa stem was analyzed for its antioxidant (DPPH, reducing power and Fe(3+) metal chelation methods) and antibacterial activities. The extract was found effective against the three antioxidant test models and exhibited strong and moderate antibacterial activity against the tested pathogenic bacteria. 相似文献
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Sanjay M. Jachak Raju GautamC. Selvam Himanshu MadhanAmit Srivastava Taj Khan 《Fitoterapia》2011,82(2):173-177
The standardized EtOAc, MeOH and 70% EtOH extracts of Tridax procumbens aerial parts showed significant inhibition of rat paw edema at a medium dose of 200 mg/kg and the EtOAC extract was the most active. These extracts were standardized by HPLC with the help of chemical markers. Further, the extracts were evaluated for COX-1 and COX-2 inhibitory activity and EtOAc extract exhibited the highest inhibition of COX-1 and COX-2 at 50 μg/mL. Cent aurein, centaureidin and bergenin were isolated as COX-1 and COX-2 inhibitory principles from the EtOAc extract. The extracts also exhibited antioxidant activity against DPPH and ABTS free radicals. The anti-inflammatory activity of T. procumbens aerial parts could be at least in part due to COX-1, COX-2 enzyme inhibition and free radical-scavenging activities which may be attributed to the presence of flavonoids and other polyphenols in the extracts. 相似文献
16.
Aldini G Piccoli A Beretta G Morazzoni P Riva A Marinello C Maffei Facino R 《Fitoterapia》2006,77(2):121-128
The antioxidant profile of extracts from solid olive residue (SOR) of c.v. Coratina, a cultivar widely diffused in the south of Italy, using both cell-free and cell-based experimental models, was investigated. A total hydroalcoholic extract (polyphenols content 19.7%) and a purified extract (Oleaselecttrade mark) (polyphenols content 35.1%) were tested for their ability to quench the stable free radical DPPH, the peroxyl radicals (ORAC assay), by monitoring the loss in fluorescence of R-phycoerythrin induced by the peroxyl radical generator AAPH and their ability to inhibit the cumene hydroperoxide-induced lysis of rat red blood cells (RBC). The total hydroalcoholic extract showed IC(50) 26.96+/-1.53 microg/ml in the DPPH assay, that 10 microg/ml were equivalent to 2.11+/-0.12 microg/ml Trolox (ORAC assay) and IC(50) 1.7+/-0.20 microg/ml in the RBC hemolysis. The Oleaselect extract was 4 to 5 folds more active than the hydroalcoholic extract in all the experimental models, with IC(50) values of 7.36+/-0.38 microg/ml in the DPPH test and of 0.38+/-0.03 microg/ml in RBC; the antioxidant activity in the ORAC assay was slightly greater than that of Trolox (10 microg/ml equivalent to 11.45+/-0.40 microg/ml). The scavenging effect of the extract in the ORAC assay was compared to that of verbascoside (the main polyphenol component) and of caffeic acid (the basic constituent of verbascoside): the results indicate that caffeic acid (10 microg/ml equivalent to 35.70+/-2.95 microg/ml Trolox) is more potent than verbascoside (10 microg/ml equivalent to 15.42+/-1.21 microg/ml Trolox) in entrapping peroxyl radicals. Finally the antioxidant activity of the Oleaselect extract was confirmed in human umbilical endothelial cells (EC) exposed to the site-specific peroxyl radical inducer AAPH, where a massive lipid peroxidation process (marker the fluorescence probe BODIPY) takes place, paralleled by a marked loss of cell viability (calcein assay). The purified extract (1-20 microg/ml) pre-incubated with EC for 1 h dose-dependently inhibited both the lipid-peroxidation damage and cell death. Taking into account the total polyphenol content, these results clearly indicate a greater antioxidant activity for the purified extract, due to a cooperative antioxidant interaction among its polyphenol constituents. 相似文献
17.
Protective effect of saponins from Argania spinosa against free radical-induced oxidative haemolysis
Saponins from Argania spinosa at a non-haemolytic concentration diminish by 53.2% erythrocyte haemolysis induced by free radicals. 2 mM aspirin and acetaminophen diminish by 75% and 68% , respectively, erythrocyte haemolysis induced by free radicals, while 0.3 muM vitamin E shows no significant antioxidant activity. Interestingly, a combination of 1 mg/l of A. spinosa saponins and vitamin E at 0.3 muM resulted in a 68% level of protection against free radical-induced erythrocyte haemolysis, which may suggest that A. spinosa saponins enhance the antioxidant effect of vitamin E. In contrast, no synergic effect was observed for acetaminophen (2 mM) when in combination with vitamin E (0.3 muM). These results demonstrate the antioxidant properties of saponins from A. spinosa and their ability to potentate the antioxidant effect of vitamin E. 相似文献
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Two new phenylethanoid glycosides magnoloside D (1) and E (2), together with nine known compounds, were isolated from the polar part of methanol extract of the stem bark of Magnolia officinalis. The structures of the new compounds were established on the basis of spectral analysis. Anti-spasmodic activity of four major constituents (3, 4, 9 and 11) was tested in isolated colon of rat, compounds 3, 4, and 9 showed inhibition against acetylcholine, with the effect similar to that of magnolol and honokiol. At the same time, antioxidant activity of the isolated compounds was investigated using a DPPH and an ORAC assay. All of the compounds, except compound 8 showed potent antioxidant capacity in the ORAC assay, while compounds 1-5 and 11 exhibited potent antioxidant activity in the DPPH assay. 相似文献
19.
目的]印度黄檀叶含有多酚及类黄酮物质,研究印度黄檀叶多酚及其抗氧化活性,可为其利用提供依据。[方法]以印度黄檀叶为原料,乙醇为提取液,经单因素实验与正交试验设计,检测在不同乙醇浓度、提取时间、提取温度及超声功率120 w时3个因素进行响应面优化试验,确定印度黄檀多酚的提取工艺;同时,鉴定印度黄檀叶乙醇-水提取液对DPPH-自由基的清除能力。[结果]低浓度印度黄檀叶多酚能发挥更强的抗氧化能力,其提取液对清除DPPH自由基的半数抑制质量浓度(IC_(50))约为3.2 mg·L~(-1),略大于Vc的2.5 mg·L~(-1);不过,其还原能力略低于Vc。[结论]印度黄檀叶内富含多酚类物质,具有很强的体外抗氧化活性,可作为天然抗氧化植物资源开发利用。 相似文献
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From a biologically active extract from the fungus Fomitopsis rosea, two new lanostane triterpenes were isolated, 3α-(3′-butylcarboxyacetoxy)oxepanoquercinic acid C 1 and 3α-hydroxy-24-methylene-23-oxolanost-8-en-26-carboxylic acid 2, along with three known triterpenes, 3–5, and the epidioxy sterol derivative 6. The structures of the compounds were elucidated based on their spectral properties. All triterpenes demonstrated antibacterial activity against S. aureus but possessed no antiradical activity against DPPH radicals. 相似文献