显齿蛇葡萄叶总黄酮对苯并芘染毒小鼠血清和肝脏抗氧化酶的影响

目的:探讨显齿蛇葡萄叶总黄酮对苯并芘染毒小鼠血清和肝脏抗氧化酶的影响.方法:用显齿蛇葡萄叶总黄酮给小鼠灌服2周后,一次性灌胃苯并芘染毒,取血和肝脏测定超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-PX)、过氧化氢酶(CAT)、r-谷氨酰转肽酶(r-GT)活性和丙二醛(MDA)含量.结果:显齿蛇葡萄叶总黄酮能明显提高小鼠血清和肝脏中SOD、GSH-PX、CAT的活性,降低r-GT 活性及MDA 含量.结论:显齿蛇葡萄叶总黄酮具有抗氧化作用,可能是显齿蛇葡萄叶总黄酮的抗致癌物作用机制之一.     

显齿蛇葡萄叶提取物对苯并芘染毒小鼠血清和肝脏抗氧化酶的影响

目的：探讨显齿蛇葡萄叶提取物对苯并芘染毒小鼠血清和肝脏抗氧化酶的影响。方法：用显齿蛇葡萄叶提取物给小鼠灌服2周后,一次性灌胃苯并芘染毒,取血和肝脏测定超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH—Px）、过氧化氢酶（CAT）、γ-谷氨酰转肽酶（γ-GT）活性和丙二醛（MDA）含量。结果：显齿蛇葡萄叶提取物能明显提高小鼠血清和肝脏中SOD、GSH—PX、CAT的活性,降低γ-GT活性及MDA含量。结论：显齿蛇葡萄叶提取物具有抗氧化作用,可能是其抗致癌物作用机制之一。     

显齿蛇葡萄叶提取物对大鼠肝癌前病变模型抗氧化酶活性的影响

目的:探讨显齿蛇葡萄叶提取物在大鼠肝脏化学致癌初期对血清及肝脏抗氧化酶活性的影响,从而进一步探索其抗致癌作用的可能机制.方法:按改良的Solt Father方法建立大鼠肝癌前病变模型,用显齿蛇葡萄叶水提物及总黄酮饲养大鼠6周后,取血及肝脏测定超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-px)、谷胱甘肽-S-转移酶(GSH-ST)、过氧化氢酶(CAT)、丙二醛(MDA)及r-谷氨酰转肽酶(r-GT).结果:显齿蛇葡萄叶水提物及总黄酮在大鼠肝脏化学致癌初期对血清和肝脏中SOD、GSH-px、GST、CAT的活性有明显回升作用,降低MDA含量,并能抑制癌前病变标志物r-GT活性表达.结论:显齿蛇葡萄叶提取物具有抗氧化和抑制癌前病变标志物的作用,可能是显齿蛇葡萄叶的抗致癌机制之一.     

卷柏属7种药用植物的提取物抑制黄嘌呤氧化酶的活性研究

目的:研究并比较卷柏属7种药用植物的28种提取物在体外对黄嘌呤氧化酶的抑制活性。方法:用带有酶动力学分析软件的紫外分光光度计,测定28种提取物对黄嘌呤氧化酶的抑制活性,波长290 nm、黄嘌呤氧化酶8.32×10-3U/ml,黄嘌呤0.05 mmol/L,反应时间为1 min。结果:卷柏属7种药用植物的乙酸乙酯提取物和95%乙醇提取物对黄嘌呤氧化酶显示出一定的抑制活性。结论:乙酸乙酯提取物和95%乙醇提取物是卷柏属药用植物抑制黄嘌呤氧化酶活性部分,可进一步分离纯化得到有效化合物。     

索骨丹提取物抑制黄嘌呤氧化酶活性及抗氧化作用

目的 观察索骨丹不同提取物对黄嘌呤氧化酶(XOD)的影响及抗氧化作用.方法 采用铁氰化钾还原法测定还原力,通过邻二氮菲和Fe2+产生有色络合物及XOD催化黄嘌呤生产尿酸的方法,分别测定索骨丹提取物对几种反应体系吸光度值的影响.结果 索骨丹乙醇提取物对XOD的最大抑制率为85.18％,水提物和醋酸乙酯提取物略次之,醋酸乙酯提取物具有较强的还原能力,乙醇提取物与亚铁离子螯合率最高达75％.结论 索骨丹提取物具有较强的抑制XOD活性的作用并具有较强的体外抗氧化作用.     

葡萄中抗氧化物质的作用及其机制研究进展

近年来 ,有关葡萄和葡萄酒中的抗氧化物质的研究逐渐深入 ,并日益得到人们的重视。研究表明 ,葡萄果肉、果皮、葡萄籽以及葡萄酒中均含有抗氧化的活性物质 ,因此兴起了以饮用葡萄酒代替乙醇类饮品的保健举措。葡萄中含有的抗氧化活性成分对许多与之相关的疾病有一定的预防和改善作用。已有研究表明 ,葡萄籽提取物具有抗炎、抗风湿、抗变态反应、抗肿瘤、减轻缺血再灌注损伤、延缓衰老、减慢早老性痴呆和帕金森氏病发展进程、以及调节血管细胞功能、抑制低密度脂蛋白氧化和降低血小板凝聚等保护作用 [1 ,2 ]。体外实验表明 ,此类抗氧化剂对自…     

柑橘属药材乙酸乙酯提取物抑制黄嘌呤氧化酶作用的谱效关系研究

目的 阐明不同柑橘属药材乙酸乙酯提取物指纹图谱特征峰对黄嘌呤氧化酶抑制作用的贡献程度.方法 建立枳实、青皮、陈皮、橘红和香橼乙酸乙酯提取物指纹图谱,HPLC法测定黄嘌呤氧化酶-黄嘌呤反应体系尿酸生成量,评价各提取物对黄嘌呤氧化酶活性的影响,采用灰关联度分析法研究谱效关系,对照品比对法鉴定主要色谱峰.结果 谱效关系分析表明,各药材提取物的黄嘌呤氧化酶抑制活性是多成分共同作用的结果,各色谱峰所代表的化学成分对抑制黄嘌呤氧化酶活性的贡献大小顺序为圣草次苷＞柚皮苷＞柚皮素＞橙皮苷＞桔皮素＞川陈皮素＞新橙皮苷＞橙皮素.结论 不同柑橘属药材乙酸乙酯提取物指纹图谱特征峰与黄嘌呤氧化酶抑制作用有一定的对应关系.     

新疆红芪水提物对D-半乳糖致衰老小鼠氧自由基代谢的影响

目的:研究新疆红芪水提取物对衰老模型小鼠的影响,从氧自由基代谢方面初步探讨其抗衰老的作用机制.方法:采用D-半乳糖致亚急性衰老小鼠模型,测定小鼠肝脏、脑组织中超氧化物歧化酶(SOD),谷胱甘肽过氧化物酶(GSH-PX)活性,丙二醛(MDA)的含量,脑组织中单胺氧化酶(MAO)的活性,以及胸腺指数和脾脏指数.结果:新疆红芪水提取物可明显降低D-半乳糖衰老小鼠肝脏和脑组织中过高的MDA含量,上调其过低的抗氧化酶SOD,GSH-PX活性,降低脑组织中MAO的活性,提高胸腺、脾脏指数.结论:新疆红芪水提取物可通过增强机体清除氧自由基能力,提高抗氧化酶活性而发挥抗衰老作用.     

紫苏叶提取物对黄嘌呤氧化酶的抑制作用

目的考察紫苏叶提取物对黄嘌呤氧化酶的抑制作用。方法紫外分光光度法检测单位时间内酶促反应体系中尿酸含量的变化,计算紫苏叶提取物对黄嘌呤氧化酶的抑制率。双倒数作图法确定紫苏叶提取物对黄嘌呤氧化酶的抑制类型,Dixon作图法计算紫苏叶提取物对黄嘌呤氧化酶的抑制动力学常数Ki。结果紫苏叶提取物对黄嘌呤氧化酶的抑制作用随着提取物质量浓度增大而增强,5 mg/mL时抑制率达到43.93%,IC50为5.80 mg/mL。动力学分析表明,紫苏叶提取物对黄嘌呤氧化酶的抑制属于竞争性可逆抑制,抑制动力学常数Ki为2.19 mg/mL。结论紫苏叶提取物对黄嘌呤氧化酶有显著抑制作用,可为相关抑制剂治疗高尿酸血症提供一定的理论和技术支撑。     

葡萄种子提取物对盐酸/乙醇诱导胃粘膜损害的影响

葡萄种子提取物含有的原花色甙(PA)具有抗氧化活性,可以抑制LDL等的氧化。本次探讨了葡萄种子提取物(GSE-L 与     

Antioxidant activity of ethanolic and aqueous extracts of Uncaria tomentosa (Willd.) DC

The antioxidant properties of aqueous and ethanolic extracts of the Uncaria tomentosa bark were evaluated. The analysis included trolox equivalent antioxidant capacity (TEAC), peroxyl radical-trapping capacity (PRTC), superoxide radical scavenging activity (SOD) and quantitation of total tannins (TT) and total phenolic compounds (TPC). The obtained results indicate high antioxidant capacity of the studied materials in comparison to the other extracts of fruits, vegetables, cereals and medicinal plants. Higher antioxidant activity and total phenolic compounds of the alcoholic preparations -- TEAC=0.57 mmol of Trolox/g, PRTC=0.52 mmol of Trolox/g and SOD=0.39 U/mg than of the aqueous preparation -- TEAC=0.34 mmol of Trolox/g, PRTC=0.19 mmol of Trolox/g and SOD=0.10 U/mg were observed. These results might suggest higher medical suitability of alcoholic extracts. However, the highly elevated level of tannins in alcoholic extracts may cause undesirable gastric effects.     

Chemical composition analysis, antioxidant, antiglycating activities and neuroprotective effects of S. choloroleuca, S. mirzayanii and S. santolinifolia from Iran

This study was designed to examine antioxidant activities, antiglycating abilities and neuroprotective effects of methanolic extracts of Salvia choloroleuca, Salvia santolinifolia and Salvia mirzayanii from Iran. The extracts were screened for their possible antioxidant activities by several biochemical assays such as DPPH, FRAP, β-carotene bleaching and TEAC assays. HPLC analysis of these extracts led to the separation of a number of components such as catechine and rosmarinic acid. Based on our results, all these plants had antioxidant and antiglycating activities, among them S. choloroleuca seems to be the most effective one. Furthermore, these species not only showed no cytotoxic effects in neuron-like PC12 cells, but also protected them against oxidative stress-induced cell death, exerted by H(2)O(2). We further showed that these plants increase superoxide dismutase and catalase levels, reduce lipid peroxidation and up regulate hemeoxygenase-1 and glutamylcysteine synthetase proteins. This study raised the possibility of developing these plants as potential neuroprotective agents.     

Polyphenols and antioxidant capacity of Bulgarian medicinal plants

Extracts of 21 plants used in Bulgarian phytotherapy for the treatment of respiratory, gastrointestinal and other inflammatory disorders were screened in vitro for antioxidant activity and phenolic compounds content. Plant extracts were prepared as herbal teas following the ethnic use. The water-phase TEAC (Trolox equivalent antioxidant capacity) of the teas were compared to that of the famous tea-like beverages mate, rooibos and honeybush, and to that of green and black tea, well known for their high antioxidant potential. The content of total phenolics in the teas was determined spectrometrically according to the Folin-Ciocalteu procedure and calculated as quercetin equivalents (QE). Seven Bulgarian medicinal plants were with high phenolics content and antioxidant properties: Pulmonaria officinalis L. (Boraginaceae) (TEAC 2.02+/-0.14 mM/QE 673.39+/-9.92 microM), Hypericum perforatum L. (Hypericaceae) (TEAC 3.75+/-0.14 mM/QE 881.93+/-6.68 microM), Agrimonia eupatoria L. (Rosaceae) (TEAC 3.76+/-0.5mM/QE 702.29+/-6.82 microM), Origanum vulgare L. (Lamiaceae) (TEAC 5.87+/-0.2mM/QE 1653.61+/-11.52 microM), Melissa officinalis L. (Lamiaceae) (TEAC 4.06+/-0.31 mM/QE 1370.09+/-41.38 microM), Rubus sp. diversa (Rosaceae) (TEAC 4.23+/-0,12 mM/QE 608.95+/-5.95 microM), Cotinus coggygria Scop. (Anacardiaceae) (TEAC 7.05+/-0.19 mM/QE 923.33+/-14.19 microM). Therefore, Bulgarian herbs can be considered to be a rich source of water-soluble antioxidants and/or phenolic compounds as compared to studied foreign plants.     

管花肉苁蓉提取物的抗氧化活性研究

目的研究管花肉苁蓉甲醇提取物和乙醇提取物的抗氧化活性,并对这两种提取物进行比较以确定能获得更高药效的提取剂。方法采用测定总酚含量、总黄酮含量、清除DPPH自由基能力及其总抗氧化能力一氧自由基吸收量（ORAC）和抗氧化当量（TEAC）来研究管花肉苁蓉的抗氧化活性。结果甲醇和乙醇提取物中含有一定量的总酚[（32．65±6．22）mgGA／g和（31．45±3．54）mgGA／g],总黄酮含量较高[（65．33±6．71）mgRE／g和（62．70±8．56）mgRE／g];两种提取物均可以有效清除DPPH自由基,半数清除浓度分别为（141．50±3．50）μg/ml和（174．82±31．85）μg／ml;乙醇提取物的ORAC和TEAC值分别为（438．59±24．14）仙molTE／g和（137．18±2．47）μmol TE／g,均高于甲醇提取物[（368．34±25．64）μmolTE／g和（114．42±1．42）μmol TE／g],其中TEAC值的差异显著（P〈0．05）。结论两种提取物均有较高的抗氧化活性,建议选择70％的乙醇作为提取剂可以获得具有较高抗氧化活性的管花肉苁蓉提取物。     

Antioxidant activities of extracts from five anti-viral medicinal plants

The antioxidant activities of five medicinal plants (Ampelopsis sinica, Ampelopsis humiliforlia var. heterophylla, Potentilla freyniana, Selaginella labordei and Chrysanthemum multiflorum), used in the Hubei province of China, have been investigated using both enzymatic and non-enzymatic in vitro antioxidant assays. Extracts from all five of the plants inhibited xanthine oxidase and lipoxygenase activities, and were scavengers of the ABTS*+ radical cation using the Trolox equivalent antioxidant capacity assay (TEAC). Extracts from Potentilla freyniana and Selaginella labordei down-regulated cyclooxygenase-2 gene expression, measured by real-time RT-PCR, in human colon adenocarcinoma CaCo-2 cells.     

Antioxidant and cytotoxic activities of Retama raetam subsp. Gussonei

The aim of this study was to evaluate the in vitro antioxidant and cytotoxic activities of the methanol extracts of Retama raetam subsp. gussonei leaves and seeds. The antioxidant activity of the extracts was assessed by means of two different tests: (1) bleaching of the stable 2,2-diphenyl-1-picrylhydrazil (DPPH) radical; and (2) lipid peroxidation of liposomes which were prepared from bovine brain extract. In both tests used leaves extract showed a significant antioxidant effect. The extract of leaves also demonstrated a good cytotoxic activity against COR-L23 (large cell carcinoma) cell line.     

Antioxidants in medicinal plant extracts. A research study of the antioxidant capacity of Crataegus, Hamamelis and Hydrastis

The antioxidant capacity of extracts of Crataegus oxyacantha, Hamamelis virginiana, Hydrastis canadensis, plants native to Europe and North America which have long been used in herbal medicine for the treatment of cardiac and circulatory functions, has been investigated. The total antioxidant potential conferred by all hydrogen donating antioxidants present in these extracts has been assessed by the ABTS assay and the relative order of antioxidant potential has been established. Gas chromatography coupled to mass spectrometry (GC-MS) has been used for the chemical identification of the antioxidant volatile compounds present in the extracts. The GC-MS data were related to the results obtained using the ABTS assay.     

Antioxidant and 15-lipoxygenase inhibitory activities of the Malian medicinal plants Diospyros abyssinica (Hiern) F. White (Ebenaceae), Lannea velutina A. Rich (Anacardiaceae) and Crossopteryx febrifuga (Afzel) Benth. (Rubiaceae)

The African flora contains numerous medicinal plants whose biological and chemical properties are incompletely known. Antioxidant and radical scavenging properties of plants are subject to intensive research. In the work described here, we have investigated the antioxidant activity of the plants Diospyros abyssinica (root bark), Lannea velutina (root bark and stem bark) and Crossopteryx febrifuga (seeds). Extracts of different polarity were assayed for radical scavenging activity, using the stable free radical diphenylpicrylhydrazyl, and for inhibition of enzymatic lipid peroxidation mediated by soybean 15-lipoxygenase. All plants investigated showed activity, but there were large differences between plants and between extracts. In general, Diospyros abyssinica and Lannea velutina were richer in antioxidants than Crossopteryx febrifuga. Lipophilic extracts were not active as radical scavengers, but did inhibit 15-lipoxygenase. Semipolar extracts (80% aqueous ethanol and methanol) of Diospyros abyssinica and Lannea velutina showed the highest activity both as radical scavengers and lipoxygenase inhibitors, and also gave the highest extract yields. These plants therefore appear to be excellent sources of antioxidants.     

In vitro and in silico anti-oxidant, cytotoxicity and biological activities of Ficus benghalensis and Duranta repens

Objective: To report in vitro anti-oxidant activity and cytotoxicity of hydroalcoholic extract of Ficus benghalensis (bark) and Duranta repens(whole plant), and present the probable biological spectrum of major anti-oxidants from both plants. Methods: The coarse powder of both plants was first extracted with 70% ethanol (maceration) and followed by 99% ethanol (Soxhlet-extraction). Anti-oxidant activity of the extracts was evaluated by using DPPH, H2O2, 2,2''-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS), NO scavenging assay, total antioxidant capacity, cupric reducing antioxidant capacity (CUPRAC), and metal chelating assay. Cytotoxicity of both extracts was evaluated by using MTT assay in both tumor and normal cell lines i.e. Chinese hamster ovary cells (CHO) and A549 cells. Biological activity of individual anti-oxidant compounds was identified by using prediction of activity spectra for substances and a docking study was performed by using autodock4.0. Results: Hydroalcoholic extract of F. benghalensis and D. repens showed the highest free radical scavenging capacity (ABTS) and chelating capacity respectively. Both extracts showed minimum cytotoxicity in normal cell lines compared to tumor cell lines. Computer imitation hits reflected the multiple biological activities agreeing with the folk use and some scientific reports. Further, we found the potent binding affinity of predicted anti-oxidant compounds with multiple protein molecules involved in oxidative stress. Conclusion: The present study reports the probable anti-oxidant mechanism for two folk agents and also presents probable pharmacological activities via computer simulations.     

Antioxidant activity of supercritical extract of Melissa officinalis subsp. officinalis and Melissa officinalis subsp. inodora

The antioxidant activity of Melissa officinalis subsp. officinalis and of Melissa officinalis subsp. inodora extracts, obtained by using carbon dioxide under supercritical conditions was investigated. The samples were prepared in two steps. A preliminary extraction at 90 bar and 50 degrees C eliminated the essential oil, then a further extraction at 300 bar and 50 degrees C obtained the high molecular mass extract. These samples were tested for autoxidation and the iron or EDTA-mediated oxidation of linoleic acid at 37 degrees C in the absence of solvent, in in vitro systems. During linoleic acid autoxidation and its EDTA-mediated oxidation both M. officinalis and M. inodora extracts showed an antioxidant activity, and no significant differences in their efficacy were observed. None showed any prooxidant activity.