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1.
Rhizobium sp. N613胞外多糖的抗氧化活性   总被引:2,自引:1,他引:1       下载免费PDF全文
以铁氰化钾和铁离子为检测系统测定了Rhizobium sp.N613胞外多糖(REPS)对氧化物的还原力;H2O2和Fe2+为羟自由基生成系统检测了REPS对羟自由基的清除作用;邻苯三酚自氧化法检测了REPS对超氧阴离子的清除作用;并体外检测了REPS对H2O2引起的氧化溶血现象的抑制作用及对小鼠肝组织脂质过氧化损伤的保护作用。结果显示,REPS对氧化物具有明显的还原力,其对羟自由基的清除作用达到35.46%(多糖浓度为2mg/mL),对超氧阴离子的清除作用达到36.84%(多糖浓度为0.78mg/mL),对H2O2引起的氧化溶血现象的抑制作用达到43.84%(多糖浓度为1.14mg/mL),对小鼠肝组织脂质过氧化的保护作用达到34.46%(多糖浓度为1.14mg/mL),表明REPS具有良好的抗氧化作用,有着重要的应用价值。  相似文献   

2.
嗜麦芽假单胞菌黑色素的抗氧化作用研究   总被引:4,自引:1,他引:3  
采用NBT光化学反应法测定嗜麦芽假单胞菌黑色素对超氧阴离子自由基的清除作用,结果表明黑色素能明显地清除超氧阴离子自由基。4μg的黑色素对超氧阴离子自由基的清除率为83.6%。黑色素有明显的抗脂质过氧化作用,能抑制鼠肝匀浆在37℃温育下生成丙二醛,72μg抑制率为92.5%。黑色素能够降低由H2O2所致的红细胞溶血作用,经H2O2作用后,溶血率为65.3%,经黑色素抗氧化作用后溶血率为52.5%。  相似文献   

3.
不同提取方法对桔梗多糖体外抗氧化性的影响   总被引:1,自引:0,他引:1  
本实验考查热水浸提法、超声波提取法、微波提取法和复合酶提取法在提取桔梗多糖时对其活性所产生的影响。在模拟体外抗氧化条件下,从总还原能力、清除超氧阴离子能力、清除羟自由基能力、清除DPPH·自由基能力和体外抗肝组织自发性脂质过氧化能力等五个方面,对不同方法提取的桔梗多糖的抗氧化活性进行了分析和评估。结果表明:微波法提取的桔梗多糖体外抗氧化效果最好且差异显著(P0.01)。此方法提取的桔梗多糖对羟自由基、DPPH·自由基的清除和对脂质过氧化作用的抑制均具有较强效果,其最大多糖浓度的清除率或抑制率均接近或超过50%,但对超氧阴离子自由基的清除能力相对较弱,最大清除率仅有25%。  相似文献   

4.
微生物源性抗氧化剂体外抗氧化能力的初步研究   总被引:4,自引:0,他引:4  
目的:研究微生物源性抗氧化剂的体外抗氧化能力.方法:在体外分别测定微生物源性抗氧化剂、α-生育酚(Vε)、抗坏血酸(VC)、L-硫辛酸、表没食子酸儿茶素的还原能力,羟自由基、超氧阴离子自由基和DPPH自由基清除能力及抗脂质过氧化能力,比较微生物源性抗氧化剂与其他抗氧化剂抗氧化能力.结果:微生物源性抗氧化剂有较强的抗氧化能力,体外清除羟自由基、超氧阴离子自由基、DPPH自由基能力的半数有效量(EC50)分别为184.5μg、48.7μg、66.1 μg.与常见抗氧化剂相比,微生物源性抗氧化剂对氧自由基及氮自由基都有较好的清除自由基作用.结论:微生物源性抗氧化剂体外抗氧化作用明显,有进一步开发的价值.  相似文献   

5.
广藿香[Pogostemon cablin(Blanco)Benth.],常用的中药材之一,含有丰富的挥发油,药理活性清楚,但广藿香精油的抗氧化活性鲜有报道。本文以广藿香精油为原料,对其清除羟自由基的能力、清除超氧阴离子活性、还原能力、总抗氧化能力及抗脂质过氧化活性进行评价,为深入研究广藿香精油的抗氧化活性提供实验依据。  相似文献   

6.
甘青铁线莲花水提取物的抗氧化活性研究   总被引:2,自引:0,他引:2  
本文采用邻二氮菲-Fe2 氧化法,邻苯三酚自氧化法以及卵黄脂蛋白不饱和脂肪酸(PUFA)过氧化体系,对甘青铁线莲花水提取物清除超氧阴离子自由基(O-·2 )和羟自由基(·OH )以及抑制卵黄脂蛋白脂质过氧化(LPO)作用的效果进行了测定.结果表明:甘青铁线莲花水提取物有清除O-2、OH的能力,同时能抑制卵黄脂蛋白脂质过氧化(LPO)作用,在相同干物质浓度下(黄酮含量为2.20 μg),抑制卵黄脂蛋白脂质过氧化(LPO)作用最强、O-2次之、OH最弱,这说明甘青铁线莲花水提取物有抗氧化作用,且水提物抗氧化活性在一定浓度范围内与其黄酮类化合物含量呈正相关.  相似文献   

7.
顶羽菊抗氧化活性研究   总被引:3,自引:0,他引:3  
目的:探讨顶羽菊提取物的抗氧化活性。方法:采用Folin-Ciocaheu法测定顶羽菊水提物和醇提物中的多酚含量,并以芦丁为标准品测定其黄酮含量;通过总还原力测定法、Fenton法、改良的邻苯三酚自氧化法、过氧化脂质测定、亚硝酸盐清除率测定和亚硝胺合成阻断率测定,分别对顶羽菊提取物的总还原力、超氧阴离子自由基和羟自由基清除能力、脂质过氧化抑制作用、清除亚硝酸盐自由基和亚硝胺阻断率进行测定。结果:顶羽菊水提物和醇提物中含有以黄酮类为主要成分的多酚类物质;具有较强的还原性和清除超氧阴离子自由基、羟自由基的活性,且醇提物的作用高于水提物;二者对脂质过氧化的抑制率达47%以上;顶羽菊提取物具有较强的清除亚硝酸钠和阻断亚硝胺合成的能力,水提物对亚硝酸盐的最大清除率为60.4%,醇提物对亚硝胺合成的阻断率为86.6%。结论:顶羽菊醇提物可作为抗氧化剂和防癌剂,用于清除机体内自由基、抗脂质氧化、延缓机体衰老、预防心血管系统疾病和癌症的发生。  相似文献   

8.
金樱子提取液体外抗氧化作用研究   总被引:1,自引:0,他引:1       下载免费PDF全文
目的:探讨金樱子(Rosa Laevigata Mickx.,RLM)提取液的体外抗氧化活性,以更好的评估金樱子的作用。方法:通过体外实验研究金樱子提取液对羟自由基(-OH)、超氧阴离子(O2-)的清除作用;研究金樱子水提取液对正常大鼠肝、肾组织匀浆脂质过氧化产物丙二醛(Malondialdehyde,MDA)生成的影响以及金樱子水提取液对过氧化氢(H2O2)诱导的红细胞氧化溶血的保护作用。结果:金樱子提取液清除-OH及O2-作用呈现出明显的剂量依赖性,可显著抑制大鼠离体肝、肾组织中MDA的生成,还可以明显抑制H2O2诱导的大鼠红细胞氧化性溶血。结论:金樱子提取液体外具有明显的抗氧化活性。  相似文献   

9.
两株乳酸杆菌SY13和LJJ对活性氧的耐受性   总被引:1,自引:0,他引:1  
【目的】从传统发酵乳制品中筛选具有抗氧化能力的乳酸菌菌株并对其抗氧化特性进行评价。【方法】分别利用乳酸杆菌SY13和LJJ完整细胞和无细胞提取物对亚油酸过氧化的抑制效果,对DPPH自由基、羟自由基、超氧阴离子自由基清除能力,对过氧化氢的耐受性以及对亚铁离子的螯合能力和还原活性进行了研究。【结果】结果表明,SY13和LJJ对亚油酸过氧化的最大抑制率分别达到了62.95%和66.16%;两菌株的无细胞提取物清除超氧阴离子和羟自由基的的效果较好,LJJ完整细胞对超氧阴离子和羟自由基没有清除能力;SY13和LJJ对DPPH自由基的清除能力及对亚铁离子的螯合能力都是完整细胞优于无细胞提取物,还原活性分别相当于305 μmol/L和294 μmol/L的L-cysteine。【结论】以上指标测定的结果说明,这两株乳酸杆菌具有较好的抗氧化能力,具有潜在的应用价值。  相似文献   

10.
山楂原花色素的抗氧化作用研究   总被引:9,自引:0,他引:9  
本文用比色法测定山楂原色素(Proanthocyanidins from the fruits of hawthorn,HPA)的抗氧化作用,即对羟自由基、超氧负离子的清除作用以及抗脂质过氧化的作用,并且通过细胞学实验验证其对上皮细胞的抗氧化损伤的保护作用。试验表明:山楂原色素有很强的抗氧化作用,其作用在浓度为0.1mg/ml-1.0mg/ml之间随着浓度的增大而增强,对超氧负离子的清除和抗脂质过氧化作用尤为明显。在浓度为1mg/ml时,对羟自由基和超氧负离子的清除率分别为59.8%和90.0%,对细胞氧化损伤的保护率为41.96%;浓度为0.5mg/ml时对脂质过氧化的抑制率达91.9%。试验同时还比较了葡萄籽原花色素(Proanthocyanidins from the fruts of grape,GPA)和Vc的抗氧化作用,结果表明:山楂原花色素与葡萄素(Proanthocyanidins from the fruits of grape,GPA)和Vc的抗氧化作用,结果表明:山楂原色素与葡萄籽原花色素效应相当,并远远高于Vc的效应。  相似文献   

11.
Aluminum (Al), oxidative stress and impaired cholinergic functions have all been related to Alzheimer's disease (AD). The present study evaluates the effect of aluminum on acetylcholinesterase (AChE) and lipid peroxidation in the mouse brain. Mice were loaded by gavage with Al 0.1 mmol/kg/day 5 days per week during 12 weeks. The mice were divided into four groups: (1) control; (2) 10 mg/mL of citrate solution; (3) 0.1 mmol/kg of Al solution; (4) 0.1 mmol/kg of Al plus 10 mg/mL of citrate solution. AChE activity was determined in the hippocampus, striatum, cortex, hypothalamus and cerebellum and lipid peroxidation was determined in the hippocampus, striatum and cortex. An increase of AChE activity was observed in the fourth group (Al + Ci) in the hippocampus (36%), striatum (54%), cortex (44%) and hypothalamus (22%) (p<0.01). The third group (Al) presented a decrease of AChE activity in the hypothalamus (20%) and an enhancement in the striatum (27%). Lipid peroxidation, measured by TBARS (thiobarbituric acid reactive substances), was elevated in the hippocampus and cerebral cortex when compared with the control (p < 0.01). The effect of aluminum on AChE activity may be due to a direct neurotoxic effect of the metal or perhaps a disarrangement of the plasmatic membrane caused by increased lipid peroxidation.  相似文献   

12.
The main aim of this work was to provide baseline data on aspects of pro-oxidant and antioxidant processes in different life-stages of the marine amphipod Gammarus locusta. The activities of antioxidant enzymes and levels of lipid peroxidation were determined in whole body juveniles, subadults, and male and female adults of a laboratory population of G. locusta. Fatty acid composition of individuals at these different stages of development was also characterised in order to examine the contribution that polyunsaturated fatty acids (PUFA) might make to the peroxidation status of animals. The antioxidant enzymes, measured in whole body 100,000 supernatants, comprised catalase (CAT, EC 1.11.1.6), superoxide dismutase (SOD; EC 1.15.1.1) and glutathione peroxidase (GPX; EC 1.11.1.9). Fatty acids were analysed as fatty acid methyl esters (FAME). Lipid peroxidation was examined in terms of the levels of lipid peroxides determined as thiobarbituric acid-reactive malondialdehyde equivalents. Age-related changes were seen in antioxidant enzyme status: levels of SOD (p<0.01) and GPX (p<0.001) activities decreased progressively during development from juveniles to adults. Sex-related changes in GPX activity were also seen, the levels being higher in adult males than females (p<0.001). The amount of FAME present in whole body amphipod also changed over the life span. Among PUFA, the eicosapentaenoic (C20:5n-3), arachidonic (C20:4n-6) and docosahexaenoic (C22:6n-3) were the most abundant acids in this species, and both their individual concentrations and total PUFA increased progressively with age (up to 3.3-fold; p<0.001). The latter changes may contribute to the explanation of the observed differences in peroxidation status of the animals with age; thus, levels of lipid peroxides increased up to 40% in adult males compared to other age-classes (p<0.01). Overall, the decline in antioxidant enzyme activities, coupled with increased levels of PUFA, as the individual grows older, may render the older animals more susceptible to lipid peroxidation and oxidative stress.  相似文献   

13.
Heat stress is a major stressor that can lead to male reproductive dysfunction. Sertoli cells play a crucial role in spermatogenesis by providing germ cells with structural and nutritional support, and contributing to blood–testis barrier formation. Vitamin C (Vc) is an antioxidant capable of neutralizing reactive oxygen species and preventing lipid peroxidation widely used because it is inexpensive and highly accessible. In the present study, we investigated the protective effect of Vc on TM4 cells following heat stress. Pretreatment with Vc could effectively inhibit apoptosis (p < 0.01), lipid peroxidation, and lactate dehydrogenase (LDH) activity. However, a significant increase in the malondialdehyde (MDA) level and LDH activity (p < 0.01) was observed in TM4 cells without Vc‐pretreatment, in conjunction with vacuole degeneration and karyopyknosis. In addition, both the messenger RNA and protein levels of CryAB, Hsp27, Hsp70, and Hsp110 substantially increased in the 3 and 12 hr recovery groups (p < 0.01). Vc also prevented microtubule aggregation following heat stress. These results suggest that pretreatment with Vc‐protected TM4 cells against heat stress by reducing the level of oxidative stress and inducing heat shock protein expression.  相似文献   

14.
Enhanced production of free radicals and oxidative stress induced by hyperglycemia play a central role in the pathogenesis of diabetes and its complications. This study assessed the attenuation by dietary caloric restriction on the oxidative and lipid peroxidative effects of diabetes in the liver through reduction in body and organ weights and concomitant metabolic changes. Three-month-old male Wistar rats were subjected to ad libitum feeding and 30% caloric restriction for 9 weeks before induction of diabetes by intraperitoneal injection of 35 mg/kg body weight streptozotocin. The animals were sacrificed 2 weeks after streptozotocin treatment depicting the onset of diabetes. Caloric restriction significantly reduced the organ weights (p<0.01), malondialdehyde (p<0.01) and catalase activity (p<0.01), but significantly increased glutathione reductase activity (p<0.01), and GSH/GSSG ratios (p<0.05). Caloric restriction also non-significantly reduced reactive oxygen species, superoxide dismutase and oxidized glutathione but increased glutathione peroxidase activity and reduced glutathione levels in the diabetic rats. Our data indicate a decrease in lipid peroxidation, improvement in the antioxidant defense systems and restoration of the redox status in the liver by caloric restriction. Therefore, this could provide a non-invasive antioxidant therapy early in diabetes to prevent the development of the complications associated with the disease.  相似文献   

15.
This study investigated the onset of age-related changes in the myocardial antioxidant defense system (ADS) and the vulnerability of the myocardium to oxidative stress following exercise training. Few studies have investigated the influence of the most prevalent life-prolonging strategy physical exercise, on the age-dependent alterations in the myocardial antioxidant enzyme system of female rats at mid age and to determine whether exercise-induced ADS could attenuate lipid peroxidation. Two age groups young (3 months old) and mid age (12 months old) Wistar strain female albino rats were given chronic exercise training for a period of 12 weeks. We found a striking decrease (p < 0.01) in the activity levels of superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR) in the myocardium of mid aged rats when compared to young rats by 36, 50 and 29%, respectively, suggesting the onset of age-dependent decrease in the myocardial ADS. A similar age-related decrease (p < 0.01) was observed in the reduced glutathione (GSH) content (36%). Despite the reduction in ADS, lipid peroxidation (LPO) (20%) was also decreased. In contrast, exercise training significantly elevated (p < 0.01) these antioxidant enzyme activities and the content of GSH. The increase in SOD and CAT activities were more pronounced in the mid aged rats when compared to younger rats, but increased the level of lipid peroxidation to higher levels in the mid-age group following the training regimen. The findings of the present study suggest that, although the activity levels of the myocardial antioxidant enzymes were elevated with the 12 weeks of exercise training, the changes were not sufficient enough in attenuating oxidative stress in the myocardium of female rats during this short period of exercise training.  相似文献   

16.
The concentration of the endogenous neurotoxin quinolinic acid (QA) is increased in the central nervous system of mice with herpes simplex encephalitis. We have previously shown that the antiherpetic agent acyclovir (AC) has the ability to reduce QA-induced neuronal damage in rat brain, by attenuating lipid peroxidation. The mechanism by which QA induces lipid peroxidation includes the enhancement of the iron (Fe)-mediated Fenton reaction and the generation of free radicals, such as the superoxide anion (O(2)(-)). Thus, the present study determined whether AC has the ability to reduce Fe(2+)-induced lipid peroxidation, O(2)(-) generation and QA-induced superoxide anion generation, and to bind free Fe. O(2)(-) and Fe(2+) are also cofactors of the enzymes, indoleamine-2,3-dioxygenase (IDO) and 3-hydroxyanthranilate-3,4-dioxygenase (3-HAO) respectively. These enzymes catalyse steps in the biosynthesis of QA; thus, the effect of AC on their activity was also investigated. AC significantly attenuates Fe(2+)-induced lipid peroxidation and O(2)(-) generation. AC reduces O(2)(-) generation in the presence of QA and strongly binds Fe(2+) and Fe(3+). It also reduces the activity of both IDO and 3-HAO, which could be attributed to the superoxide anion scavenging and iron binding properties, respectively, of this drug.  相似文献   

17.
Eicosapentaenoic acid (EPA) is one of the major dietary polyunsaturated fatty acids and induces apoptosis in several cancer cells. In this study, the EPA induced lipid peroxidation and response of antioxidative enzymes have been investigated in rat pheochromocytoma PC12 cells to elucidate the mechanisms of apoptosis induced by the polyunsaturated fatty acid EPA. We have analyzed superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) activities and glutathione (GSH) contents in PC12 cells after exposure to different concentrations of EPA. Lipid peroxidation was shown to increase in the presence of EPA as an indication of the oxidative damage. Lipid peroxidation was enhanced by EPA in a dose-dependent manner, and the loss of cell viability was partially reversed by vitamin E. In the case of antioxidant enzyme activities, SOD and GPX activities and GSH contents increased significantly at 50 μmol/L EPA and were respectively 2.41-fold (p < 0.01), 3.49-fold (p < 0.05), and 1.43-fold (p < 0.05) higher than controls. The CAT activity at 10 μmol/L had the highest value and was increased by 25.83% (p < 0.05) compared to control. The results suggest that in PC12 cells the mechanism of apoptosis induced by EPA may be partly due to lipid peroxidation.  相似文献   

18.
The objective was to determine the oxidative stability of Arctic char (Salvelinus alpinus) semen following dietary supplementation with lowbush blueberry (Vaccinium angustifolium) product, alpha-tocopherol, alpha-tocopherol+blueberry product, or alpha-tocopherol+astaxanthin. Sperm lipid peroxidation was initiated by challenging with ferrous sulphate/ascorbic acid (Fe(++)/Asc) at level of 0.04/0.2 mmol/L. Addition of blueberry, alpha-tocopherol, or both to char diets inhibited semen lipid peroxidation by: (a) decreasing the rate of sperm lipid peroxidation, an effect which was more pronounced with alpha-tocopherol treatments; and (b) increasing the antioxidant potential of seminal plasma, based on the lipid peroxidation process of sperm and an in vitro chicken brain tissue model. Dietary supplementation with astaxanthin and alpha-tocopherol had the same effect as the supplementation with alpha-tocopherol alone on inhibiting the lipid peroxidation process of sperm and chicken brain. Catalase-like activity increased significantly in sperm of fish fed alpha-tocopherol, blueberry, or both. There was a negative correlation (r= -0.397, P < 0.05) between catalase-like activity in sperm cells and the rate of sperm lipid peroxidation. Seminal plasma alpha-tocopherol levels increased significantly in fish supplemented with alpha-tocopherol alone or in combination with blueberry or astaxanthin. There were negative correlations between seminal plasma alpha-tocopherol levels and lipid peroxidation rates of sperm cells (r= -0.625, P < 0.01) and brain tissue (r= -0.606, P < 0.01). In conclusion, dietary supplementation of blueberry product or alpha-tocopherol inhibited lipid peroxidation in Arctic char semen. Further experiments are needed to test the effect of dietary blueberry and antioxidants on Arctic char semen quality during liquid and cryopreserved storage.  相似文献   

19.
9-(3-Mesityl-4,5-dihydroisoxazol-5-yl) homo-N-nucleosides were prepared from the 1,3-dipolar cycloaddition reactions of mesityl nitrile oxide with 9-allyl derivatives of 6-chloropurine, 6-piperidinylpurine, 6-morpholinylpurine, 6-pyrrolidinylpurine, and 6-N,N-dibenzoyladenine. The new compounds were tested in vitro for their ability: (i) to interact with 1,1-diphenyl-2-picryl-hydrazyl (DPPH) stable free radical, (ii) to inhibit lipid peroxidation, (iii) to scavenge the superoxide anion, (iv) to inhibit the activity of soybean lipoxygenase, and (v) to inhibit in vitro thrombin. Most of them found to be potent thrombin inhibitors and to inhibit in vitro lipid peroxidation. The majority of the compounds showed significant lipoxygenase inhibitory activity.  相似文献   

20.
The levels of blood lipid peroxidation, glutathione peroxidase, reduced glutathione, and vitamin C were used to follow the level of oxidative damage caused by 2.45 GHz electromagnetic radiation in rats. The possible protective effects of selenium and L-carnitine were also tested and compared to untreated controls. Thirty male Wistar Albino rats were equally divided into five groups, namely Groups A1 and A2: controls and sham controls, respectively; Group B: EMR; Group C: EMR + selenium, Group D: EMR + L-carnitine. Groups B–D were exposed to 2.45 GHz electromagnetic radiation during 60 min/day for 28 days. The lipid peroxidation levels in plasma and erythrocytes were significantly higher in group B than in groups A1 and A2 (p?<?0.05), although the reduced glutathione and glutathione peroxidase values were slightly lower in erythrocytes of group B compared to groups A1 and A2. The plasma lipid peroxidation level in group A2 was significantly lower than in group B (p?<?0.05). Erythrocyte reduced glutathione levels (p?<?0.01) in group B; erythrocyte glutathione peroxidase activity in group A2 (p?<?0.05), group B (p?<?0.001), and group C (p?<?0.05) were found to be lower than in group D. In conclusion, 2.45 GHz electromagnetic radiation caused oxidative stress in blood of rat. L-carnitine seems to have protective effects on the 2.45-GHz-induced blood toxicity by inhibiting free radical supporting antioxidant redox system although selenium has no effect on the investigated values.  相似文献   

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