松针叶绿素-胡萝卜素软膏体外清除自由基及体内抗氧化作用的研究

目的 研究松针叶绿素-胡萝卜素软膏体外清除自由基和体内抗氧化作用.方法 通过测定松针叶绿素-胡萝卜素软膏对羟自由基(·OH)、超氧阴离子自由基(O2-·)和DPPH自由基(DPPH·)的清除率,观察松针叶绿素-胡萝卜素软膏体外清除自由基能力;通过测定大鼠血清、肝匀浆和心匀浆超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活性和丙二醛(MDA)含量变化,观察松针叶绿素-胡萝卜素软膏体内抗氧化作用.结果 松针叶绿素-胡萝卜素软膏对·OH、O2-·、DPPH·均具有明显的清除能力,其IC50分别为0.53,0.23,0.56 mg/ml;能显著提高大鼠血清、肝脏和心脏中SOD、GSH-Px活性和降低MDA含量.结论 松针叶绿素-胡萝卜素软膏在体内外具有良好的抗氧化活性,为松针叶绿素-胡萝卜素软膏在食品和药物中的应用提供实验依据.     

海蜇酶解多肽分离纯化及其抗氧化活性研究

目的 研究海蜇酶解多肽的抗氧化活性.方法 采用碱性蛋白酶酶解提取海蜇多肽,用超滤方法获得不同分子量的酶解液,从还原体系、羟自由基清除体系和DPPH自由基清除体系3方面,研究海蜇酶解液抗氧化肽的活性.结果 不同分子量的海蜇酶解物具有较强还原性,对羟自由基、DPPH自由基清除作用均较强,且抗氧化活性随着浓度的增加而明显增加.从分子量来看,小于3KDa组分抗氧化活性最强,当浓度为15 mg/ml时,其对羟自由基和DPPH自由基的清除率分别为62.27％和78.25％.结论 海蜇酶解物具有抗氧化活性,且小分子肽的抗氧化活性最强.     

白花蛇舌草多糖的抗氧化活性研究

目的:评价白花蛇舌草多糖的体外抗氧化能力。方法:以热水回流提取法(料水比1∶31.26,84.71℃下提取2.07h,提取2次)从白花蛇舌草(HDW)提取的多糖为材料,通过1,1-二苯基-2苦肼基自由基(DPPH)清除率、总的抗氧化活性和还原能力测定等体外抗氧化试验来评价白花蛇舌草多糖的体外抗氧化能力。结果:白花蛇舌草多糖清除DPPH自由基、总的抗氧化活性和还原能力均随多糖浓度的增加而上升;1mg/mL的多糖对DPPH自由基的清除率高达82.66%;1mg/mL多糖的总的抗氧化活性在695nm下吸光值为1.641;1mg/mL多糖的还原能力在700nm下吸光值为0.773。结论:白花蛇舌草多糖有较强的抗氧化能力,对体外自由基有较好的清除作用。     

两种滇产木姜子属植物中总黄酮的抗氧化活性研究

目的:对滇产金平木姜子和红叶木姜子进行总黄酮含量的测定,并分别研究总黄酮的抗氧化活性。方法:用正丁醇分别浸提金平木姜子和红叶木姜子得到两种提取物,用紫外分光光度法测定各自总黄酮的含量,同时以DPPH清除率实验来评价其抗氧化活性并分别绘制DPPH随浓度变化曲线进行比较。结果:金平木姜子中黄酮提取物的DPPH自由基清除率最高为72.63%,IC50值为1.75mg/mL;红叶木姜子中黄酮提取物的DPPH自由基清除率最高为86.67%,IC50值为1.48mg/mL。结论:金平木姜子和红叶木姜子中含较丰富的总黄酮化合物,具有较强的抗氧化活性,且红叶木姜子中总黄酮的抗氧化活性高于金平木姜子。     

乌饭树叶总黄酮体外抗氧化活性

目的 研究乌饭树叶总黄酮的体外抗氧化活性.方法 用对羟基自由基和对DPPH自由基清除率和来考察其总黄酮的体外抗氧化活性大小.结果 乌饭树叶总黄酮抗氧化能力强,对DPPH自由基和羟基自由基的EC50分别为22.30 mg/L和38.00mg/L.结论 乌饭树叶是一种良好的天然抗氧化剂来源.     

藤梨根总黄酮对大鼠肝脏组织抗氧化能力及其相关基因表达的影响

目的对藤梨根总黄酮(TFAR)体内与体外的抗氧化活性及其相关机制进行研究。方法以清除1,1-二苯基-2-三硝基苯肼(DPPH)、2,2-联氮-二(3-乙基-苯并噻唑-6-磺酸)二铵盐(ABTS)自由基能力为指标对TFAR进行体外抗氧化活性实验;以D-半乳糖致衰老大鼠为模型,测定大鼠肝脏组织中丙二醛(MDA)的量及超氧化物歧化酶(SOD)、过氧化氢酶(CAT)的活力及抗氧化相关基因SOD1、SOD2、GPX1 mRNA表达。结果 TFAR对DPPH、ABTS自由基具有良好的清除作用,IC_(50)分别为27.01 mg/mL和29.55 mg/mL。与模型组比较,TFAR各给药组肝脏组织中MDA、SOD、CAT指标均有显著改善(P0.05、0.01),表现在MDA水平降低,SOD、CAT活性升高,并回调到对照组水平以上。TFAR各剂量组对指标的调控作用呈量效关系。与模型组比较,TFAR 3个剂量组均能够上调衰老模型大鼠肝脏组织上清液中SOD1、SOD2、GPX1mRNA的表达,差异显著(P0.05、0.01),且存在一定的剂量依赖关系。结论 TFAR在体外和体内均有抗氧化活性,抗氧化活性与上调大鼠肝脏组织中SOD1、SOD2、GPX1 mRNA表达有关。     

木蝴蝶总黄酮的抗氧化活性

目的:研究木蝴蝶总黄酮的抗氧化活性。方法:采用二苯代苦味酰基苯肼(DPPH)法、水杨酸法和邻苯三酚自氧化法来考察其抗氧化活性,并与Vc做比较。结果:在试验浓度内,木蝴蝶总黄酮对二苯代苦味酰基苯肼自由基(DPPH.)、羟自由基(.OH)和超氧阴离子自由基(O2-.)均有较好的清除作用,其EC50分别为19.73,231.70,318.93 mg·L-1,在9.52～57.12 mg·L-1,其对DPPH.的清除率高于VC。结论:木蝴蝶总黄酮有良好的抗氧化活性,具有进一步开发利用的价值。     

定心藤总黄酮的提取及抗氧化活性的研究

目的研究微波辅助提取定心藤总黄酮的提取工艺及其抗氧化活性。方法通过正交试验设计确定了定心藤总黄酮微波辅助提取的最佳条件,用DPPH.法研究定心藤总黄酮对自由基的清除作用。结果微波辅助提取定心藤总黄酮的最佳提取条件为微波功率处于中高火、含乙醇量65%、微波作用时间2 min、固液比1∶40;抗氧化实验表明定心藤总黄酮对DPPH.有较好的清除作用,且清除能力随浓度的增加而增强,IC50值为0.000 663(mg/mL),优于合成抗氧化剂BHA的抗氧化活性。结论微波辅助提取定心藤总黄酮的工艺便捷、效率高;定心藤总黄酮对DPPH.有较强的清除能力,具有明显的抗氧化活性。     

衢枳壳总黄酮提取工艺的优化及其抗氧化活性

目的优化衢枳壳总黄酮提取工艺,并评价其抗氧化活性。方法在单因素试验基础上,以乙醇体积分数、提取时间、料液比、提取温度为影响因素,总黄酮提取率为评价指标,正交试验优化提取工艺。考察总黄酮对DPPH、ABTS自由基的清除能力。结果最佳条件为乙醇体积分数80%,料液比1∶30,提取时间2.0 h,提取温度80℃,总黄酮提取率6.21%。总黄酮质量浓度为250μg/mL时,对ABTS自由基的清除能力与维生素C相当;为1 000μg/mL时,对DPPH自由基的清除率达88.537%,呈量效关系。结论该方法简便可靠,可用于提取具有较强抗氧化活性的衢枳壳总黄酮。     

乙醇-硫酸铵双水相体系萃取香椿籽总黄酮工艺优化及其抗氧化活性研究

目的 优化乙醇-硫酸铵双水相体系萃取香椿籽总黄酮工艺，并考察其抗氧化活性。方法 在单因素试验基础上，以乙醇体积、硫酸铵用量、香椿籽用量、超声时间为影响因素，总黄酮萃取率为评价指标，响应面法优化提取工艺。考察总黄酮对DPPH自由基、羟自由基、ABTS自由基的清除能力。结果 最佳条件为乙醇体积3.6 mL,硫酸铵用量2.2 g,香椿籽用量0.2 g,超声时间29 min,总黄酮萃取率为93.430%。总黄酮对DPPH自由基、羟自由基、ABTS自由基的清除率分别为93.68%、85.61%、82.26%。结论 该方法简便可靠，可用于乙醇-硫酸铵双水相体系萃取抗氧化活性较强的香椿籽总黄酮。     

Protective effect of steamed American ginseng (Panax quinquefolius L.) on V79-4 cells induced by oxidative stress

Heat-processed Asian ginseng roots (Panax ginseng C.A. Meyer), also known as "red ginseng" in Asia, are reported to have more bioactivity than the no-processed white ginseng roots. Therefore, American fresh ginseng roots (Panax quinquefolius L.) were processed to the red ginseng and examined changes in bioactivity during heating process. The fresh America ginseng roots were steamed at 100 degrees C for 30, 60, 90 and 120 min, and their bioactivities were examined by analyzing the content of ginsenosides and total phenolics, and measuring DPPH and superoxide radical scavenging acivity and their protective effects on V79-4 cells viability and lipid peroxidation. The heating treatment proportionally increased total ginsenosides (4.97%, w/w) content compared with white ginseng (3.27%) and total phenolics from 444.5 mg GAE/100 g to 489.6-574.2 mg GAE/100 g. The antioxidant activity also increased from 285 mg/100 g (vitamin C equivalent) to 353-487 mg/100 g. Heated ginseng showed high levels of DPPH radical scavenging activity (59.5-88.5%) and the high level of superoxide radical scavenging activity (44.2-90.9%). The heated ginseng protected cell viability against H2O2-induced oxidative damage, and enhanced the activities of superoxide dismutase and catalase by dose dependently in V79-4 cells.     

Non-ginsenoside nicotinic activity in ginseng species

Amongst the many different therapeutic applications of ginseng are beneficial effects on age-related cognitive impairments. Ageing in the brain is associated with a loss of nicotinic receptor binding and receptor stimulation increases binding. Stimulation of the CNS (central nervous system) nicotinic receptor is considered to be beneficial in relation to symptomatic treatment and neuroprotection in age-associated cognitive disorders which involve a further receptor loss. We assessed Panax ginseng, Panax quinquefolium and several chemical constituents of these plants for nicotinic activity based on displacement of 3H-(-)nicotine from human brain cerebral cortex membranes in vitro. Dose-dependent displacement was evident in crude ethanol extracts of Panax ginseng and Panax quinquefolium. Assay of an extract of Panax ginseng showed the plant to have affinity for both the nicotinic receptor, and to a lesser extent the muscarinic receptor (IC50 2.12 mg/mL and 5.25 mg/mL respectively). Activity was largely conserved after the extraction of choline and other water soluble quaternary ammonium compounds (QAC), indicating that the activity of the plant extracts was not due to choline. Displacement binding assay of some purified chemical constituents, including a number of ginsenosides, showed that these were not primarily responsible for Panax activity. The active chemical constituent has yet to be identified, but the demonstrated nicotinic activity of ginseng warrants further investigation with reference to therapeutic activity in age-related conditions such as dementia.     

河北香菊中黄酮类成分体外抗氧化活性研究及构效关系探讨

目的:通过研究河北香菊中5种黄酮类成分木犀草素、芹菜素、金合欢素、木犀草素-7-O-β-D-葡萄糖苷、金合欢素-7-O-β-D-葡萄糖苷的体外抗氧化活性,探讨河北香菊的抗氧化机制及黄酮类化合物抗氧化活性的构效关系。方法:采用紫外-可见分光光度法测定对DPPH自由基的清除作用及对H2O2诱导的大鼠红细胞溶血的抑制作用;用硫代巴比妥酸法(TBA)测定对H2O2诱导的大鼠脑匀浆脂质过氧化反应的抑制作用;用谷胱甘肽过氧化物酶(GSH-Px)试剂盒法测定对大鼠血浆中谷胱甘肽过氧化物酶的影响。结果:河北香菊中5种黄酮类成分在清除DPPH自由基、抗红细胞溶血、抑制脑匀浆脂质过氧化、提高谷胱甘肽过氧化物酶活力方面均呈现出较好的活性,活性顺序表现为木犀草素>木犀草苷>芹菜素>金合欢素>金合欢苷。结论:河北香菊所具有的抗氧化活性与其所含黄酮类成分清除自由基、抑制脂质过氧化、提高抗氧化物酶活性有关,且黄酮类化合物的抗氧化活性与其结构中的羟基数目和位置以及糖苷的空间位阻有关。     

不同产地酸藤子根总黄酮含量及抗氧化活性研究

目的:测定不同产地酸藤子根总黄酮含量及评价其体外抗氧化活性与总黄酮含量的相关性.方法:选用广西、广东11种不同产地酸藤子,采用超声提取法对酸藤子根总黄酮进行提取,选用紫外分光光度法测定其总黄酮含量;通过测定酸藤子根总黄酮的总抗氧化能力以及清除1,1-二苯基-2-三硝基苯肼(DPPH)自由基的能力来评价酸藤子根体外抗氧化...     

中药复方柴胡疏肝散体内外抗氧化活性及其与抗抑郁作用的 潜在关系

目的：研究中药复方柴胡疏肝散（CSGS）的体内外抗氧化活性, 探讨其抗氧化活性与抗抑郁作用之间的联系, 助以阐释CGGS抗抑郁的作用机制。方法：采用总抗氧化能力测定（FRAP法）, DPPH （1 ,1-二苯基-2-苦基苯肼） 自由基（DPPH法）、ABTS[ 2 ,2-连氮（3-乙基苯并噻唑啉-6-磺酸）二铵盐]阳离子自由基（ABTS法）、超氧阴离子（O2·^-）及羟自由基（·OH）清除能力测定5 种方法, 以维生素C为阳性对照, 研究CSGS体外抗氧化活性。建立束缚氧化应激模型, 通过测定全血中谷胱甘肽（GSH）含量, 肝组织中超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、丙二醛（MAD）含量研究CSGS体内抗氧化作用。结果：CSGS体外具有一定的铁离子还原能力和自由基清除能力, 其还原能力（FRAP法）每克CSGS提取物相当于 0.24 mmol FeSO4, 清除DPPH自由基、ABTS阳离子自由基、O2·^-及 ·OH的IC50分别为 0.83, 1.03, 10.31 和 7.79 mg·mL^-1。体内抗氧化活性研究显示, 在束缚应激状态下, CSGS给药组小鼠与模型组小鼠比较具有相对高的SOD和CAT活性及GSH含量, 相对较低的MDA水平。结论：复方柴胡疏肝散具有抑制脂质过氧化、缓解氧化应激损伤、调控机体抗氧化水平的药理作用, 其抗抑郁作用可能与其抗氧化活性有一定相关。     

Heteropteris aphrodisiaca O. Machado : effects of extract BST 0298 on the oxidative stress of young and old rat brains.

The plant Heteropteris aphrodisiaca O. Machado is widely employed in Brazilian popular medicine as a stimulant, a tonic and a remedy for nervous debility. Several other plant products with similar therapeutic applications may have such effects based on the antioxidant content of polyphenols (gallates, cathecols, etc.) and flavonoids. The aim of this work was to investigate the effects of Heteropteris aphrodisiaca O. Machado extracts on the antioxidant defences and oxidative stress of young and old rat brains. Tests of lipoperoxidation in vitro, comparing H. aphrodisiaca extracts with butylhydroxytoluene (BHT), a classic antioxidant, showed an efficient inhibition of lipoperoxidation (Q(1/2) = 3.3 microg/mL). Chronic treatment of young and old rats with 50 mg plant extract/kg body weight resulted in a significant increase in superoxide dismutase (SOD) activities (40%) in the brain of old rats, but no changes in catalase and glutathione peroxidase (GPX). No significant variations in antioxidant enzyme activities were observed in the brains of young rats. However, significantly lower levels of lipoperoxidation (30%) were detected in the brain of young rats upon plant extract administration, suggesting that H. aphrodisiaca extracts reduced the oxidative stress to brain lipids.     

Effects of wild ginseng (Panax ginseng C.A. Meyer) leaves on lipid peroxidation levels and antioxidant enzyme activities in streptozotocin diabetic rats

The aim of this study was to examine the possible antioxidant activities of wild Panax ginseng leaf extract intake in streptozotocin (STZ)-induced diabetic rats (WGLE). Initial blood glucose levels increased abruptly after streptozotocin injection. After 4 weeks of WGLE supplementation, blood glucose levels were lower in animals fed 40 mg/kg (266 mg/dL) and 200 mg/kg (239 mg/dL) than those in no-WGLE fed diabetic rats (464 mg/dL). The concentration of blood TBARS, which are considered the main products of glucose oxidation in blood, was also lowered by WGLE supplementation. These results indicate that WGLE supplementation is involved in suppressing a sudden increase in blood glucose levels and a consequent decrease in TBARS levels in diabetic rats. TBARS levels in the liver, kidney and spleen of WGLE-fed diabetic groups were also significantly lower than in the control diabetic group indicating that oral administration of WGLE effectively suppresses lipid peroxidation that occurs in the organs of diabetic rats. Antioxidant activities of WGLE supplementation further extend in suppressing activities of antioxidant related enzymes, such as glutathione peroxidase (GSH-Px), catalase (CAT) and superoxide dismutase (SOD), in organs of diabetic rats. These results confirm the effectiveness of WGLE supplementation in detoxifying free radicals that are produced excessively in diabetic-induced complications.