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Free radical mechanisms of halogen coexistence promoting pollutants formation
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作者 Mingxuan Wang Shuting Liu +5 位作者 Linjun Qin Qingyu Guo Guorui Liu Dong Cao Lili Yang Minghui Zheng 《Journal of Environmental Sciences》 2026年第2期559-568,共10页
Halogens are common in industrial thermal processes and can induce formation of toxic organic pollutants.Currently,the specific effects of coexisting halogens on toxic pollutant formation are unclear.In this study,we ... Halogens are common in industrial thermal processes and can induce formation of toxic organic pollutants.Currently,the specific effects of coexisting halogens on toxic pollutant formation are unclear.In this study,we found the boosting effects of halogens on organic pollutants formation during thermal processes.In situ electron paramagnetic resonance spectroscopy was used to distinguish the organic free radical intermediates of organic pollutants during thermal processes.The pure chlorine-containing reaction system dominantly induce the formation of highly chlorinated phenoxy radicals,whereas the pure bromine-containing reaction system induce the formation of semiquinone radicals.The results provide clear evidence for the molecular mechanisms by which halogen coexistence boosts pollutants formation.Coexisting halogens made the reactions much more complex.Bromine atom radicals(Br·)can enhance the level of active chlorine atoms radicals(Cl·),then(1)facilitating highly chlorinated organic radicals and toxic pollutants formation,(2)activating polycyclic aromatic hydrocarbons molecules for subsequent ring growth and(3)accelerating oxidation reactions.Combining the identification of organic free radical intermediates and characteristics of products,detailed mechanisms of halogens on the formations of organic pollutants during thermal-related processes were clarified,which can be helpful for their efficient control in the widespread bromines and chlorines co-existence reaction system. 展开更多
关键词 Halogenated compounds Organic free radical intermediates Halogen coexistence Thermal process Fourier transform ion cyclotron resonance mass spectrometry
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Optimization of Solvent-Free Microwave Extraction of Essential Oil from the Fruits of Schisandra chinensis and Its DPPH Radical Scavenging Activity
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作者 CHEN Xiao-qiang ZHANG Ying +2 位作者 ZU Yuan-gang YU Xue-ying LI Jia-lei 《食品科学》 EI CAS CSCD 北大核心 2011年第14期85-89,共5页
This study was undertaken to optimize the solvent-free microwave extraction conditions and DPPH radicalscavenging activity of essential oil from Schisandra chinesis fruits.The uniform design method was employed for pr... This study was undertaken to optimize the solvent-free microwave extraction conditions and DPPH radicalscavenging activity of essential oil from Schisandra chinesis fruits.The uniform design method was employed for process optimization.The optimal extraction conditions were determined as follows:extraction time,50 rain;microwave power,800 W;and amount of water addition for pretreatment,40%.Under these conditions,the extraction yield of essential oil was 0.92%.A total of 35 compounds were identified by GC-MS in the obtained essential oil with a total content of 91.06%,mostly consisting of ylangene(34.81%),β-himachalene(10.74%)andα-bergamotene(9.22%).The ICs0 value of the essential oil against DPPH free radicals was determined as 3.01 mg/mL.In conclusion,solvent-free microwave extraction is a feasible method for essential oil extraction from Schisandra chinensis fruits. 展开更多
关键词 Schisandra chinesis essential oil solvent-free microwave extraction chemical composition dpph radical scavenging activity
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Correlation of free radical level and apoptosis after intracerebral hemorrhage in rats 被引量:7
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作者 韩宁 丁素菊 +1 位作者 吴涛 朱幼丽 《Neuroscience Bulletin》 SCIE CAS CSCD 2008年第6期351-358,共8页
Objective To investigate the correlation of perihematomal free radical level and neuronal apoptosis following the intracerebral hemorrhage (ICH). Methods Animals were randomly divided into 4 groups: sham operation ... Objective To investigate the correlation of perihematomal free radical level and neuronal apoptosis following the intracerebral hemorrhage (ICH). Methods Animals were randomly divided into 4 groups: sham operation group, model group, 1 mg/kg edaravone group, and 3 mg/kg edaravone group. Each group was then divided into seven subgroups, in which the rats were correspondingly killed at 6 h, 12 h, 24 h, 48 h, 72 h, 7 d or 14 d (n = 1 in each subgroup of the sham group, and n = 6 in each subgroup of the other 3 groups). By Horseley-Clarke technique, autoblood (80 μL) were administered into the left caudate putamen of SD rats in a double administration-withdrawal way. Rats in the sham group were needled in but not administered with autoblood. The ICH model was then evaluated by Bederson's scale. Around the hematoma, the levels of malonaldehyde (MDA) and hydroxyl radical were tested by spectrophotometer, and the process of apoptosis was tested by terminal deoxynucleofidyltransferase-mediated dUTP-biotin nick end labeling (TUNEL) method. Results (1) ICH significantly increased the levels of MDA and hydroxyl radicals. Significant differences in MDA and hydroxyl radical contents were observed among the four groups. (2) In the sham group, a small number of TUNEL-positive cells were found. In the other three groups, the TUNEL-positive cells were observed at 6 h, increased significantly at 24 h, and reached peak level at 3 d, then fell profoundly at 7 d, but remained detectable at 14 d. (3) The positive correlation existed between apoptosis and free radical level (r = 0.2003), and existed between apoptosis and MDA content (r = 0.6563) in the brain. Conclusion Post-hemorrhagic apoptosis was related to the production of free radicals, indicating that the elevated free radicals following the ICH could induce neuron and glial cell apoptosis. 展开更多
关键词 intracerebral hemorrhage free radical APOPTOSIS TUNEL EDARAVONE
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Factors Influencing the Effects of Theabrownin in Pu-erh Tea on Scavenging DPPH Radicals 被引量:9
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作者 董文明 谭超 龚加顺 《Agricultural Science & Technology》 CAS 2013年第2期317-323,共7页
[Objective] This study aimed to explore factors influencing the effects of theabrownin in Pu-erh tea on scavenging DPPH radicals. [Method] Taking Pu-erh tea as main research object, theabrownin in Pu-erh tea from tea ... [Objective] This study aimed to explore factors influencing the effects of theabrownin in Pu-erh tea on scavenging DPPH radicals. [Method] Taking Pu-erh tea as main research object, theabrownin in Pu-erh tea from tea piles with different times of mixture, stored for different years and processed by both the old and new techniques were extracted and isolated. And DPPH method was used to study the effects of theabrownin solution and tea liquor on scavenging radicals and their antioxidant activity. [Result] The result showed that the theabrownin content in Pu-erh tea from tea piles with one to four times of mixture revealed a first declining and subsequently rising trend. Under different pH conditions, the rates of DPPH radical scavenging of 1 mg/ml theabrownin solution made from tea piles with different times of mixture decreased gradually with the increase of pH, and all the rates were lower than that of the control vitamin C solution; the rates of DPPH radical scavenging of theabrownin from tea samples stored for different years and produced by different techniques dropped slowly within pH range 3.0-6.0; when pH was higher than 6.0, the rates of DPPH radical scavenging of theabrownin from tea samples produced by both new and traditional techniques in 2001 declined obviously, while the declining trend was not obvious in either the black tea or the Pu-erh tea produced by new technique in 2005. Under different theabrownin concentrations, the rates of DPPH radical scavenging of theabrownin solution made from tea piles with different times of mixture ascended as the concentration increased and the highest rate occurred in tea pile with four times of mixture, reaching up to 46.56%±0.88%; for tea samples stored for different years and produced by different techniques, the rates of DPPH radical scavenging of theabrownin rose gradually with the increase of the theabrownin concentration; the rate of radical scavenging of theabrownin in the black tea ascended obviously and that in Pu-erh tea was decreasing within the concentration range of 0.04 -0.06 mg/ml. At pH6.0, the DPPH radical scavenging ability of theabrownin in 0.1 mg/ml theabrownin solution and tea liquor containing 0.1mg/ml theabrownin from tea piles with different times of mixture ascended with the time of mixture; solution made from tea samples produced by different techniques in different years, the DPPH radical scavenging ability of theabrownin solution and tea liquor followed: Pu-erh tea produced by the new technique in 2001 ﹥ Pu-erh tea produced by the old technique in 2001﹥ Pu-erh tea produced by the new technique in 2005. And the DPPH radical scavenging ability of theabrownin in tea liquor containing 0.1 mg/ml theabrownin was higher than that in 0.1 mg/ml theabrownin Solution made from tea samples either with different times of mixture or produced by different techniques in different years. The above results indicated that many factor influenced the effects of theabrownin on eliminating DPPH radicals, including the time of fermentation, fermentation technique, years of storage, concentration and pH all had great influence on the effects of theabrownin on eliminating radicals. To ensure a good effect on scavenging radicals, it is better to prepare theabrownin at pH6.0 with concentration between 0.08 and 0.1 mg/ml for drinking. [Conclusion] Results of this study provide a basis for developing functional products of theabrownin from Pu-erh tea in the future. 展开更多
关键词 Pu-erh tea THEABROWNIN Antioxidant activity dpph radicals
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Extraction Storage and Qualitative Analysis of Free Radicals Scavenging Substances from Sweet Potato Leaves 被引量:9
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作者 王友升 董银卯 +1 位作者 宋彦 黑维俭 《Agricultural Science & Technology》 CAS 2008年第2期1-5,9,共6页
[ Objective ] The research aimed to provide reference for the application of extracts from sweet potato leaves in anti-aging cosmetics. [ Method ] The extraction and storage conditions for free radicals scavenging sub... [ Objective ] The research aimed to provide reference for the application of extracts from sweet potato leaves in anti-aging cosmetics. [ Method ] The extraction and storage conditions for free radicals scavenging substances from sweet potato leaves were optimized by orthogonal test and the bioactive components in extracts were investigated by correlation analysis. [ Result] Sweet potato leaves contain the bioactive substances scavenging DPPH free radical and hydroxyl free radical. Extracting solvent species is the most important factor that influencing extraction yield. The optimal extraction and storage conditions are as following: water as solvent, pH 8.0 of extracting liquid, storage at 25 ℃. There is a good positive linear relationship between the content of total phenols in sweet potato leaves and corresponding scavenging rates against both the DPPH free radical and hydroxyl free radical. For the content of total flavones in sweet potato leaves, just a correlation with scavenging rate against hydroxyl free radical shown in test. [ Conclusion] The phenols in ex- tracts could effectively scavenge both the DPPH free radical and hydroxyl free radical, whereas the flavones in extracts can only function on the hydroxyl free radical. 展开更多
关键词 Sweet potato leaves free radicals scavenging Total phenol Total flavones
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Effects of Water─soluble Components Isolated from Salviamilltiorrhiza on Oxygen Free Radical Generation and LipidPeroxidation 被引量:10
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作者 李定友 徐理纳 刘小光 《Journal of Chinese Pharmaceutical Sciences》 CAS 1995年第2期107-112,共6页
The effects of water─soluble components isolated from Salvia miltiorrhiza on oxygen free radical prodction and lipid peroxidation were estimated. Five components(10 μmol/L)were shown to inhibit superoxide anion gen... The effects of water─soluble components isolated from Salvia miltiorrhiza on oxygen free radical prodction and lipid peroxidation were estimated. Five components(10 μmol/L)were shown to inhibit superoxide anion generation by xanthine─xanthine oxidase system. It was also demonstrated that six components( 100 μmol/L) prevented H_2O_2─induced hemolysis and MDA fonnation in mouse erythrocytes.The effects of Sal A, Sal B, Sal C and Ros A were dose dependent. In Langendorff rat heart, pretreatment with Sal A 20μmol/L significantly prevented MDA production induced by 30 min reoxygenation after 45 min anoxia.The results indicated that there were also other potent antioxidant componentts in Salvia milliorrhiza besides Dphl and Pal. The protection of Sal A against myocardial anoxiareoxygenation inury may be mainly ascribed to its oxygen free radical scavenging activity. 展开更多
关键词 Salvia miltiorrhiza Salvianolic acid A Myocardial anoxiareoxygenation free radicals Lipid peroxide
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On the Scaling Study for the A_f-A_g Type Free Radical Polymerization
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作者 王海军 吕中元 +1 位作者 黄旭日 李泽生 《分子科学学报》 CAS CSCD 1998年第1期60-65,共6页
根据Af-Ag自由基加聚反应的数量分布函数,导出凝胶点附近的渐进分布函数和高分子矩的表示式.进一步应用标度变换,得到了描述溶胶-凝胶相变的广义标度律,从而揭示了Af-Ag自由基加聚的固化反应是一个相变过程.
关键词 标度律 自由基聚合 凝胶点 高分子矩
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Oxidative Stress and Free Radical Damage in Patients With Acute Dipterex Poisoning 被引量:15
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作者 JUN-FuZHOU WENZHOU +2 位作者 SHU-MEIZHANG YAN-ERLUO HUAI-HONGCHEN 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2004年第2期223-233,共11页
Objective To investigate whether acute dipterex poisoning (ADP) may cause oxidative stress and free radical damage in the bodies of acute dipterex poisoning patients (ADPPs), and to explore the mechanisms by which ADP... Objective To investigate whether acute dipterex poisoning (ADP) may cause oxidative stress and free radical damage in the bodies of acute dipterex poisoning patients (ADPPs), and to explore the mechanisms by which ADP may cause oxidative stress and free radical damage. Methods Fifty ADPPs and fifty healthy adult volunteers (HAVs) whose ages, gender and others were matched with the ADPPs were enrolled in a randomized controlled study, in which concentrations of nitric oxide (NO), vitamin C (VC), vitamin E (VE) and P-carotene (P-CAR) in plasma as well as concentration of lipoperoxide (LPO), and activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and acetylcholinesterase (AChE) in erythrocytes were determined by spectrophotometric analytical methods. Results Compared with the average values of experimental parameters in the HAVs group, the average values of plasma NO and erythrocyte LPO in the ADPPs group were significantly increased (P<0.0001), while those of plasma VC, VE and P-CAR as well as erythrocyte SOD, CAT, GPX and AChE in the ADPPs group were significantly decreased (P<0.0001). Bivariate correlation analysis and partial correlation analysis suggested that when NO and LPO values were increased, and VC, VE, β-CAR, SOD, CAT and GPX values were decreased in the ADPPs, AChE value was decreased gradually in the ADPPs (P<0.001-0.0001). Reliability analysis of experimental parameters reflecting oxidative stress and free radical damage in the ADPPs showed that the reliability coefficient (8 items) alpha=0.6909, and the standardized item alpha=0.8574. Conclusion The findings in the present study suggest that ADP can cause oxidative stress and free radical damage, and inhibit markedly erythrocyte acetylcholinesterase activity in ADPPs. 展开更多
关键词 Dipterex Dipterex poisoning Oxidative stress free radical damage free radicals Oxidation LIPOPEROXIDATION ACETYLCHOLINESTERASE
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Relationship between Acute Organophosphorus Pesticide Poisoning and Damages Induced by Free Radicals 被引量:29
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作者 ZHOU JUN-FU XU GEN-BO FANG WEI-JUN 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2002年第2期177-186,共10页
关键词 Organophosphorus pesticide poisoning free radicals Lipoperoxides Nitric oxide ANTIOXIDANTS Antioxidases
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Component Analysis and Free Radicals Scavenging Activity of Physalis alkekengi L. Polysaccharide 被引量:22
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作者 CHENG Ying-kun LI Lei MENG Zhao-kun HOU A-li WU Yu-jie TENG Li-rong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第2期167-170,共4页
A crude polysaccharide was extracted from Physalis alkekengi L. fruit. HPLC was used for the component analysis of the polysaccharide. The results indicate that Physalis alkekengi L. polysaccharide(PAP) was composed... A crude polysaccharide was extracted from Physalis alkekengi L. fruit. HPLC was used for the component analysis of the polysaccharide. The results indicate that Physalis alkekengi L. polysaccharide(PAP) was composed of rhamnose, xylose, arabinose, galactose, and glucose. Free radicals scavenging activity of PAP was studied through 3 free radicals scavenging tests. PAP exhibited high scavenging effects on OH and DPPH radicals, and both the scavenging rates were about 80%. The scavenging rate of O2^- radical was about 22%. 展开更多
关键词 PHYSALIS POLYSACCHARIDE Component analysis free radicals scavenging activity
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Abnormal Reactions of Free Radicals and Oxidative Damages in the Bodies of Patients With Chronic Glomerulonephritis 被引量:23
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作者 ZHOUJUN-FU CHENJIA-XI 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2002年第3期233-244,共12页
Objective To study the abnormal reactions of a series of free radicals and the oxidative damages induced by free radical abnormal reactions in the bodies of patients with chronic glomerulonephritis. Methods Eighty ... Objective To study the abnormal reactions of a series of free radicals and the oxidative damages induced by free radical abnormal reactions in the bodies of patients with chronic glomerulonephritis. Methods Eighty chronic glomerulonephritis patients (CGNP) and eighty healthy adult volunteers (HAV) were enrolled in a random control study, in which concentrations of nitric oxide (NO) in plasma, lipoperoxides (LPO) in plasma and in erythrocytes, and vitamin C (VC), vitamin E (VE) and beta-carotene (?CAR) in plasma as well as activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in erythrocytes were determined with spectrophotometric assays. Results Compared with the average values of the above biochemical parameters in the HAV group, the average values of NO in plasma, and LPO in plasma and erythrocytes in the CGNP group were significantly increased (P = 0.0001), while those of VC, VE and -CAR in plasma as well as those of SOD, CAT and GPX in erythrocytes in the CGNP group were significantly decreased (P = 0.0001). Pearson product-moment correlation analysis showed that with increase of the concentration of blood creatinine as well as prolongation of the course of disease in the CGNP, the concentrations of NO in plasma, and LPO in plasma and erythrocytes in the CGNP increased gradually, while the concentrations of VC, VE and ?CAR in plasma as well as the activities of SOD, CAT and GPX in erythrocytes in the CGNP decreased gradually (P = 0.002454 0.000001). The relative risk ratio (RR) of the above biochemical parameters reflecting oxidative damages in the bodies of CGNP ranged from 6.061 to 72.429. The reliability coefficient (alpha) that the above biochemical parameters were used to reflect the oxidative damages of the CGNP was 0.8137, standardized item alpha = 0.9728, Hotelling抯 T-Squared = 1135680.191, F = 53274.6478, P = 0.000001. Conclusions The findings in this study show that in the bodies of CGNP a series of free radical chain reactions result in severe pathological aggravation and induce oxidative damages in their bodies. Therefore, suitable dose of antioxidants should be supplemented to them so as to alleviate oxidative damages in their bodies. 展开更多
关键词 Chronic glomerulonephritis free radicals Oxidation LIPOPEROXIDATION Nitric oxide Lipoperoxides ANTIOXIDANT Antioxidase Oxidative stress Oxidative damage
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Antioxidant,lipid peroxidation inhibition and free radical scavenging efficacy of a diterpenoid compound sugiol isolated from Metasequoia glyptostroboides 被引量:9
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作者 Vivek K.Bajpai Ajay Sharma +1 位作者 Sun Chul Kang Kwang-Hyun Baek 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2014年第1期9-15,共7页
Objective:To investigate the antioxidant enicacy of a biologically active dilerpenoid compound sugiol isolated from Metasequoia glyptostroboides(M.glyptostroboides)in various antioxidant models.Methods:An abietane typ... Objective:To investigate the antioxidant enicacy of a biologically active dilerpenoid compound sugiol isolated from Metasequoia glyptostroboides(M.glyptostroboides)in various antioxidant models.Methods:An abietane type diterpenoid sugiol,isolated from ethyl acetate extract of M.glyptostroboides cones,was analyzed for its antioxidant efficacy as reducing power ability and lipid peroxidation inhibition as well as its ability to scavenge free radicals such as 1,1-diphenyl-2-picryl hydrazyl,nitric oxide,superoxide and hydroxyl radicals.Results:The sugiol showed significant and concentration-dependent antioxidant and free radical scavenging activities.Consequently,the sugiol exerted lipid peroxidation inhibitory effect by 76.3%as compared to a-tocopherol(80.13%)and butylaled hydroxyanisole(76.59%).In addition,the sugiol had significant scavenging activities of l,l-diphenyl-2-picryl hydrazyl,nitric oxide,superoxide and hydroxyl free radicals in a concentration-dependent manner by 78.83%,72.42%,72.99%and 85.04%,when compared to the standard compound ascorbic acid(81.69%,74.62%,73.00%and 73.79%)and a-tocopherol/butylated hydroxyanisole(84.09%,78.61%,74.45%and 70.02%),respectively.Conclusions:These findings justify the biological and traditional uses of M.glyptostroboides or its secondary metabolites as confirmed by its promising antioxidant efficacy. 展开更多
关键词 Sugiol DITERPENOID ANTIOXIDANT free radicalS LIPID PEROXIDATION
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STUDIES ON FREE RADICAL SCAVENGING ACTIVITY IN CHINESE SEAWEEDS PART I. SCREENING RESULTS 被引量:4
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作者 严小军 房国明 娄清香 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1999年第3期240-246,共7页
Antioxidants have attracted the attention of researchers due to their beneficial effects as free radical scavengers. Application of a stable free radical named 1,1 diphenyl 2 picrylhydrazyl(DPPH) to screen the free ra... Antioxidants have attracted the attention of researchers due to their beneficial effects as free radical scavengers. Application of a stable free radical named 1,1 diphenyl 2 picrylhydrazyl(DPPH) to screen the free radical scavenging activity in 27 species of Chinese seaweed showed that 15 of them had significant activity in at least one of the organic solvent extracts. The most interesting seaweed species were Gelidium amansii, Gloiosiphonia capillaris, Polysiphonia urceolata, Sargassum kjellmanianum, Desmarestia viridis, and Rhodomela teres. 展开更多
关键词 SEAWEED antioxidant free radical dpph SCAVENGING activity
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Free radical scavenging potential of Lagenaria siceraria(Molina) Standl fruits extract 被引量:3
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作者 Vijayakumar Mayakrishnan Selvi Veluswamy +2 位作者 Krishnakumari Shanmuga Sundaram Priya Kannappan Noorlidah Abdullah 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2013年第1期20-26,共7页
Objective:To elucidate free radical scavenging activity of ethanolic extract Lagenaria siceraria (L.siceraria)(Molina) fruit.Methods:The free radical scavenging activity of the L siceraria (Molina) fruit extract... Objective:To elucidate free radical scavenging activity of ethanolic extract Lagenaria siceraria (L.siceraria)(Molina) fruit.Methods:The free radical scavenging activity of the L siceraria (Molina) fruit extract was assayed by usingα,α-diphenyl-β-picrylhydrazyl(DPPH). 2,20-azinobis 3-ethyl henzothiazoline-6-sulfonate(ABTS),FRAP,reducing power,chelating ability andβ-carotene bleaching assay.Results:The IC<sub>50</sub>values of DPPH and ABTS radicalscavenging activity was found to be 1.95 mg/mL and 19 mg/mL,respectively.In ferrous chelation assay,the percentage of inhibition was found to be 89.21%.The reducing power of ethanolic extract of L siceraria(Molina) fruit was 0.068 at 1 mg/mL and increased to 0.192 at 5 mg/mL Theβ-carotene linoleate bleaching assay was 46.7%at 5 mg/mL and antioxidant activity using FRAP at 0.305 for 1 mg/mL to 0.969 for 5 mg/mL Conclusions:The results indicate that L siceraria (Molina) fruit could be an important sources of natural radical scavengers. 展开更多
关键词 Lagenaria siceraria ANTIOXIDANT dpph ABTS free radical
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Changes of free radicals and digestive enzymes in saliva in cases with deficiency inspleen-yin syndrome 被引量:17
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作者 Muxin Wei Yanmin Wu Dezheng Chen Yuchun Gu 《The Journal of Biomedical Research》 CAS 2010年第3期250-255,共6页
Objective:To explore the nature of deficiency in spleen-yin syndrome,which could provide scientific theoretical support and practical guidance for clinical Traditional Chinese Medicine(TCM)syndrome differentiation ... Objective:To explore the nature of deficiency in spleen-yin syndrome,which could provide scientific theoretical support and practical guidance for clinical Traditional Chinese Medicine(TCM)syndrome differentiation based on biology,and had a strong clinical significance.Methods:Serum Cu and Zn were detected by atomic absorption spectrophotometer,serum vitamin E by high performance liquid chromatography,serum vitamin C by 2,4-Dinitrophenylhydrazine Colorimetry,total superoxide dismutase(SOD)and Cu and Zn- SOD by the xanthine oxidase method,and malondialdehyde(MDA)by the 2-thiobarbituric acid method(TBA).Total antioxidant capacity was detected by a colorimetry kit.Amylase Activity was detected by an automatic biochemical analyzer.Lysozyme was detected by lysozyme detection plate,the diameter of bacteriolysis circle was measured and the corresponding content of lysozyme was obtained from a table of standard curve values.Results: No significant difference in total SOD and Cu,Zn-SOD was found between deficiency in spleen-yin group and normal group.However,such factors in deficiency in kidney-yin group were significantly lower than the other groups(P〈0.05).The MDA content in both deficiency in spleen-yin group and deficiency in kidney-yin group were significantly higher than that of normal group(P〈0.05),while the total antioxidant capacity was significantly lower than normal group(P〈0.05).The vitamin E content in deficiency in kidney-yin group was significantly lower than that in the other two groups(P〈0.05).No significant difference in the contents of vitamin C,Cu and Zn were observed in these groups.The Zn/Cu level in deficiency in kidney-yin group and the vitamin E level in deficiency in spleen-yin group decreased,but with no significant difference.Amylase activity in unit time in cases with deficiency in spleen-yin was lower than and had significant differences with that in normal cases,and higher than that in cases with deficiency in kidney-yin.The sectional velocity of saliva and the ratio of lysozyme in normal case group were significantly higher than other two groups,while deficiency in the spleen-yin group was significantly higher than the deficiency in kidney-yin group.Conclusion:All the results indicated that the objective pathological mechanism between the deficiency in spleen-yin and deficiency in kidney-yin was different. 展开更多
关键词 deficiency in spleen-yin deficiency in kidney-yin digestive enzymes in saliva AMYLASE salivary lysozyme salivary flow rate free radicals
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Phytochemical screening and free radical scavenging activity of Citrullus colocynthis seeds extracts 被引量:5
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作者 Nabila Benariba Rabeh Djaziri +4 位作者 Wafaa Bellakhdar Nacera Belkacem Marcel Kadiata Willy J.Malaisse Abdullah Sener 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2013年第1期35-40,共6页
Objective:To study the phytochemical screening of different extracts from Citrullus colocynthis(C.colocynthis)seeds extracts and to assess their antioxidant activity on the DPPH free radical scavenging.Methods:Phytoch... Objective:To study the phytochemical screening of different extracts from Citrullus colocynthis(C.colocynthis)seeds extracts and to assess their antioxidant activity on the DPPH free radical scavenging.Methods:Phytochemical screening,total content of polyphenols and flavonoids of C.colocynthis seeds extracts,including a crude aqueous extract(E1),a defatted aqueous extract(E2),a hydromethanolic extract(HM),an ethyl acetate extract(EA)and a n-butanol extract(n-B)was carried out according to the standard methods and to assess their corresponding effect on the antioxidant activity of this plant.Results:None of these extracts contained detectable amount of alkaloid,quinone,antraquinone,or reducing sugar.Catechic tannins and flavonoids were abundant in E1,MM and EA,whilst terpenoids were abundantly present in E1 and n-B but only weekly in HM.Coumarins were found in E2,EA and n-B.Polyphenols,expressed as gallic acid equivalent,amounted,per 100 g plant matter,to 329,1002 and 150 mg in EA,HM an E1 respectively.Flavonoids,expressed as catechin equivalent,amounted.per 100 g plant matter to 620,241 and 94 mg in EA,HM and E1 respectively.Comparable values were found in n-B and E1,with lower values in E2.Quercetin,myricetin and gallic acid were found in the EA and HM extracts by thin layer chromatography,The antioxidative effect of these extracts yielded,when tested at a concentration of 2000μg/mL in a 1,1-diphenyl-2-picrylhydrazyl assay,a reducing percentage of 88.8%with EA,74.5%with HM and 66.2%with E1,and corresponding IC_(50)of 350,580and 500μg/mL as compared to 1.1μg/mL for ascorbic acid.Conclusions:These qualitative and quantitative analytical data document the presence in C.colocynthis extracts of such chemical compounds as flavonoids responsible for the antioxidant activity,as well as other biological activities of this plant. 展开更多
关键词 CITRULLUS colocynthis POLYPHENOLS FLAVONOIDS free radical SCAVENGING
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May Chronic Childhood Constipation Cause Oxidative Stress and Potential Free Radical Damage to Children? 被引量:4
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作者 JI-YUEWANG YE-LINGWANG +1 位作者 SHENG-LIZHOU JUN-FUZHOU 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2004年第3期266-272,共7页
Objective To investigate whether chronic childhood constipation (CCC) may cause oxidative stress and potential free radical damage to children, and to explore the mechanisms by which CCC may cause oxidative stress an... Objective To investigate whether chronic childhood constipation (CCC) may cause oxidative stress and potential free radical damage to children, and to explore the mechanisms by which CCC may cause oxidative stress and potential free radical damage to chronic constipation patients (CCPs). Methods Sixty CCPs and sixty healthy child volunteers (HCVs) whose ages, gender and others were matched for the CCPs were enrolled in a randomized controlled study, in which levels of vitamin C (VC) and vitamin E (VE) in plasma as well as activities of superoxide dismutase (SOD) and catalase (CAT) in erythrocytes were determined by spectrophotometric analytical methods. Results Compared with average values of the above biochemical parameters in the HCVs group, the average values of VC and VE in plasma as well as those of SOD and CAT in erythrocytes in the CCPs group were significantly decreased (P<0.0001). Linear regression and bivariate correlation analysis showed that with prolonged course of the CCPs, the levels of VC and VE in plasma as well as the activities of SOD and CAT in erythrocytes in the CCPs were decreased gradually (P<0.0001). Conclusion The findings in the present study suggest that chronic childhood constipation causes oxidative stress and potential free radical damage to children with chronic constipation. 展开更多
关键词 Chronic childhood constipation Oxidative stress free radicals free radical damage Antioxidant Antioxidase
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Effect of resveratrol on pancreatic oxygen free radicals in rats with severe acute pancreatitis 被引量:18
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作者 Zhen-Dong Li Qing-Yong Ma Chang-An Wang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第1期137-140,共4页
AIM: To investigate the therapeutic effects of resveratrol (RESV) as a free radical scavenger on experimental severe acute pancreatitis (SAP). METHODS: Seventy-two male Sprague-Dawley rats were divided randomly ... AIM: To investigate the therapeutic effects of resveratrol (RESV) as a free radical scavenger on experimental severe acute pancreatitis (SAP). METHODS: Seventy-two male Sprague-Dawley rats were divided randomly into sham operation group, SAP group, and resveratrol-treated group. Pancreatitis was induced by intraductal administration of 0.1 mL/kg 4% sodium taurocholate. RESV was given intravenously at a dose of 20 mg/kg body weight. All animals were killed at 3, 6, 12 h after induction of the model. Serum amylase, pancreatic superoxide dismutase (SOD), malondialdehyde (MDA), and myeloperoxidase (MPO) were determined. Pathologic changes of the pancreas were observed under optical microscope. RESULTS: The serum amylase, pancreatic MPO and the score of pathologic damage increased after the induction of pancreatitis, early (3, 6 h) SAP samples were characterized by decreased pancreatic SOD and increased pancreatic MDA. Resveratrol exhibited a protective effect against lipid peroxidation in cell membrane caused by oxygen free radicals in the early stage of SAP. This attenuation of the redox state impairment reduced cellular oxidative damage, as reflected by lower serum amylase, less severe pancreatic lesions, normal pancreatic MDA levels, as well as diminished neutrophil infiltration in pancreas. CONCLUSION: RESV may exert its therapeutic effect on SAP by lowering pancreatic oxidative free radicals and reducing pancreatic tissue infiltration of neutrophils. 展开更多
关键词 Severe acute pancreatitis RESVERATROL Oxygen free radical NEUTROPHIL
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Lipophilic Enhance of Vitamin C Protective Activity Against Free-radical-induced Damage in vivo 被引量:5
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作者 LUOXu-yang LIUZai-qun +3 位作者 SUNYun-xiu SUIDa-yuan YUXiao-feng QUShao-chun 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第4期428-431,共4页
A group of experimental rats under free radical damage are given various amounts of a lipophilic vitamin C(ascorbyl-6-laurate, VC-12), and its parent compound, vitamin C, respectively. It has been found that the effec... A group of experimental rats under free radical damage are given various amounts of a lipophilic vitamin C(ascorbyl-6-laurate, VC-12), and its parent compound, vitamin C, respectively. It has been found that the effects of 1 12 mmol/kg VC-12 on decreasing triglyceride(TG), total cholesterol(TC), low density lipoprotein cholesterol (LDL-c) and lipid peroxide(LPO), and increasing high density lipoprotein cholesterol(HDL-c) and superoxide dismutase(SOD) are similar to those of 2 27 mmol/kg vitamin C. In addition, VC-12(1 12 mmol/kg) can increase the prostacycline(PGI 2) and decrease the thromboxane(TXA 2) even better than vitamin C(2 27 mmol/kg). The above facts demonstrate that the antioxidative activity of VC-12 is higher than twice that of vitamin C. So, ascorbyl-6-laurate may be a novel antioxidant drug against free radical damage. 展开更多
关键词 ANTIOXIDANT free radical Ascorbyl-6-laurate Vitamin C Blood lipid metabolism in vivo
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Inhibitory effects of grape procyanidins on free radical-induced cell damage in rat hepatocytes in vitro 被引量:10
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作者 Jin-Yi Zhong Hong-Qun Cong Li-Hua Zhang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第19期2752-2755,共4页
AIM: To study the protective effect of grape procyanidins on oxidative injury induced by ethanol and carbon tetrachloride in rat hepatocytes. METHODS: Normal rat hepatocytes as well as cells damaged by ethanol or ca... AIM: To study the protective effect of grape procyanidins on oxidative injury induced by ethanol and carbon tetrachloride in rat hepatocytes. METHODS: Normal rat hepatocytes as well as cells damaged by ethanol or carbon tetrachloride were incubated with different doses of grape procyanidins for 24 h. Cell proliferation, apoptosis and TNFα mRNA expression were subsequently determined using MTT assay, cell death ELISA and in situ hybridization. RESULTS: Proliferative levels of the control cells from ethanol and CCh injury groups significantly decreased while apoptosis and TNFα mRNA expression significantly increased compared to the normal control and grape procyanidins co-treatment groups (0.455 ± 0.051 vs 0.318 ±0.045, P 〈 0.05). In comparison with the normal control, 50 and 100 mg/L grape procyanidins significantly stimulated cell growth, with a better effect observed with 100 mg/L grape procyanidins. CONCLUSION: Grape procyanidins inhibit the hepatocyte damage induced by ethanol and carbon tetrachloride, and stimulate normal hepatocyte proliferation. 展开更多
关键词 Grape procyanidin free radical Cell proliferation Apoptosis HEPATOCYTE
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