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Component Analysis and Free Radicals Scavenging Activity of Physalis alkekengi L. Polysaccharide 被引量:19
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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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Chemical composition and free radicals restraining activity of extracts from three Manglietia species leaves 被引量:1
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作者 HE Kai-yue ZHANG Shuang-quan +2 位作者 LI Xiao-chu FAN Ya-su JIN Xiao-yan 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第3期193-198,共6页
The extracts from leaves of Manglietia insignis (Wall) Blume, Manglietia chingii Dandy and Manglietia yuyuanensis Law were prepared by organic solvent extraction and their components were analyzed by GC/MS and quant... The extracts from leaves of Manglietia insignis (Wall) Blume, Manglietia chingii Dandy and Manglietia yuyuanensis Law were prepared by organic solvent extraction and their components were analyzed by GC/MS and quantified. Meanwhile, the free radicals restraining activities were detected. The 21 compounds in M. insignis, 36 compounds in M. chigii and 20 compounds in M. yuyuanensis were identified. There were 11 common components in the extracts from three Manglietia species, and 12 components in two Manglietia species. The results of relative contents of every component in three extracts showed that the main constituents of M. insignis were terpenoids and alkene, amounting to 38.93%, followed by alkane (28.18%), the nitrogen containing compounds (15.73%) and aromatic compounds (7.23 %). The main constituents of leaf extract from M. chingii were the terpenoids and alkene, carboxylic acid, alkane and aromatic compounds, amounting to 30.22%, 14.17%, 13.87% and 13.29%, respectively, The main constituents of M. yuyuanensis were alcohol compounds, the terpenoids and alkene, and aromatic compounds, amounting to 28.00%, 25.38% and 18.00% respectively. The results showed that the three extracts had strong function of restraining oxygen free radicals. The ultra oxygen anions activity was restrained at the highest level, when the three extracts were diluted by hundred-fold, whereas the restraining capacity of hydroxyl free radicals reached maximum, when the three extracts were diluted by twenty-fold. The above results provide scientific evidences for further approaching the ecological healthy function of three MangUetia species 展开更多
关键词 MANGLIETIA EXTRACTS Chemical components free radicals restraining activity
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Sonme Factors that Affect the Free Radical-scavenging Activity of Tea Extracts 被引量:9
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作者 Zhao Xinhuai ( Northeast Agricultural University, Harbin 150030 PRC) 《Journal of Northeast Agricultural University(English Edition)》 CAS 1999年第1期62-67,共6页
Some factors that affect the free radical-scavenging activety of two tea extracts were studied in vitro. It was found that concentration of tea extract or heating tea extract or treating with activated carbon and di... Some factors that affect the free radical-scavenging activety of two tea extracts were studied in vitro. It was found that concentration of tea extract or heating tea extract or treating with activated carbon and diatomite all had obvious effect on the scavenging activety of green tea extract ,but heating or treating with diaomite had less effect on the scavenging activity of black tea extract. Ascorbic acid, for having synergic effect with tea extracts, could enhance the scavenging activity of tea extracts markedly, and the contrary was cupric ion. Reducing sugars such as fructose and glucose also had some syncrgic effect to tea extracts. 展开更多
关键词 Tea extract. hydroxyl radical. free radival-scavenging activity
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Liver Nuclear Activation of Carbon Tetrachloride or Bromotrichloromethane to Trichloromethyl and Trichloromethylperoxyl Free Radicals.Their Reactions With Lipids and Proteins 被引量:4
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作者 S. L. FANELLI G. D. CASTRO M. E. GALELLI AND J. A. CASTRO (Centro de Investigaciones Toxicologicas(CEITOX)-CITEFA/CONICET, Zufriategui 4380, 1603 Villa Martelli,Buenos Aires, Argentina)(Send correspondence to Dr. Jose Alberto Castro, Zufriategui 4380, 1 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1998年第2期101-114,共14页
The formation of·CCl3 radicals in liver nuclei was suggested by spin trapping of them with N-t-butyl-α-phenylnitrone followed by GC/MS detection of the resulting adduct. Comparison of its formation in microsomal... The formation of·CCl3 radicals in liver nuclei was suggested by spin trapping of them with N-t-butyl-α-phenylnitrone followed by GC/MS detection of the resulting adduct. Comparison of its formation in microsomal biotransformation of CCl4 was made. In aerobic nuclear activation mixtures containing NADPH and CCl4, significant decrease in the arachidonic acid content of nuclear lipids was observed (27. 8%, compared to control), the intensity of this decrease was lower than that occurring in the corresponding microsomal incubation mixtures (29.1%). Significant decreases in arachidonic acid content of nuclear and endoplasmic reticulum lipids were also observed in animals at 6 hours of poisoning with the haloalkane. During aerobic nuclear metabolism of CCl4 or CBrCl3, cholesterol oxidation products were detected: a ketocholesterol, an epoxide like structure and 7-ketocholesterol. Nuclear protein carbonyl formation was not promoted during nuclear CCl4 biotransformation. NADPH by itself may lead to protein carbonyl formation during prolonged periods of incubation. CBrCl3 in contrast, led to decreased protein carbonyl formation. No increase in nuclear protein carbonyl formation was observed in CCl4 intoxicated animals during periods of time between 1 to 6 hours after treatment. The results indicate that during nuclear biotransformation of CCl4 or CBrCl3 reactive free radicals, PUFA degradation, reactive aldehydes and cholesterol oxidation products are formed, nearby DNA and regulatory proteins. 展开更多
关键词 NADPH Liver Nuclear Activation of Carbon Tetrachloride or Bromotrichloromethane to Trichloromethyl and Trichloromethylperoxyl free radicals.Their Reactions With Lipids and Proteins free
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The Maturation and Senescence in Relation to Ca^2+,CaMContent and Ca^2+-ATPase Activity and Active OxygenMetabolism in Strawberry Fruits 被引量:3
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作者 GUAN Jun-feng, GAO Min, FAN Xiu-cai, GU Cai-qin, LI Guang-min and ZHANG Ji-shu(Institute of Agro-Physics , Plant Physiology and Biochemistry , Hebei Academy of Agricultural and Forestry Sciences ,Shijiazhuang 050051 , P. R . China College of Life Sciences , Northwestern Science and Technology Universityof Agriculture and Forestry, Yangling 712100 , P.R.China) 《Agricultural Sciences in China》 CAS CSCD 2002年第10期1151-1155,共5页
The changes in content of Ca2 + and CaM, Ca2 + -ATPase activity and active oxygen metabolism during strawberry (Fragaria ananassa Duch. cv. Chunxing) fruits maturation and senescence were investigated in this study. T... The changes in content of Ca2 + and CaM, Ca2 + -ATPase activity and active oxygen metabolism during strawberry (Fragaria ananassa Duch. cv. Chunxing) fruits maturation and senescence were investigated in this study. The results showed that the soluble Ca2+ content and SOD activity in fruits tended to decline and O2 production rate to increase, the Ca2 + -ATPase activity peaked at first and then declined during fruits maturation and senescence. There were the highest CaM content at white stage in preharvest fruits and at marked senescence stage in postharvest ones. The above biochemical changes in fruits stored at low temperature (4℃)were slower than those stored at normal temperature(25℃). Thus, it indicated that the stimulation of calcium messenger system and accumulation of active oxygen free radical were closely related to fruits maturation and senescence. 展开更多
关键词 STRAWBERRY FRUIT MATURATION SENESCENCE Calcium messenger system active oxygen free radical
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Cadmium Accumulation and Its Toxicity in Brittle Culm 1(bc1),a Fragile Rice Mutant 被引量:1
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作者 SHAO Guo sheng CHEN Ming xue +4 位作者 ZHANG Xiu fu XU Chun mei WANG Dan ying QIAN Qian ZHANG Guo ping 《Rice science》 SCIE 2007年第3期217-222,共6页
Cadmium (Cd) accumulation and toxicity in rice plants were characterized and identified by using brittle culm 1 (bcl), a fragile rice mutant and its wild type (Shuangkezao, an indica rice) as materials by hydrop... Cadmium (Cd) accumulation and toxicity in rice plants were characterized and identified by using brittle culm 1 (bcl), a fragile rice mutant and its wild type (Shuangkezao, an indica rice) as materials by hydroponics. The low Cd level didn't obviously affect the growth parameters in both rice genotypes, but under high Cd levels (1.0 and 5.0 μmol/L), the growth of both rice plants were substantially inhibited. Moreover, bcl tended to suffer more seriously from Cd toxicity than Shuangkezao. Cd accumulation in both rice plants increased with the increase of Cd levels. There was a significant difference in Cd accumulation between the two rice genotypes with constantly higher Cd concentration in bcl, which also accumulated more Cd at 0, 0.1, and 1.0 μmol/L Cd levels. The same case was found in the two rice plants grown on Cd-contaminated soil. This suggested that cell wall might play an important role in Cd accumulation in rice plants by the physiological mechanisms. The malondialdehyde (MDA) content, superoxide dismutase (SOD) and peroxidase (POD) activities in rice plants were affected differently under Cd treatments, and which implied that POD might play the main role in detoxifying active oxygen free radical. A significant difference in antioxidative system between the two rice genotypes was found with constantly higher MDA content, SOD and POD activities in bcl. In summary, bcl accumulated more Cd and appeared to be more sensitive to Cd stress compared with its wild type. 展开更多
关键词 rice (Oryza sativa) cadmium brittle culm mutant malondialdehyde oxidative stress TOXICITY superoxide dismutase peroxidase active oxygen free radical enzyme activity
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Syntheses and Crystal Structures of [Na(H_2O)_(1/2)]X and NH_2(CH_2CH_3)_2X and Antioxidant Activity of the Former 被引量:1
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作者 刘彬 杨伯伦 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第9期1112-1120,共9页
In order to enhance the water-solubility and biological utilization rate of chrysin, sodium 5,7-dihydroxylflavone-8-sulfonate (1, [Na(H2O)1/2]X, X = C15H9OSO3, 5,7-dihydroxylfla- vone-8-sulfonate) was synthesized ... In order to enhance the water-solubility and biological utilization rate of chrysin, sodium 5,7-dihydroxylflavone-8-sulfonate (1, [Na(H2O)1/2]X, X = C15H9OSO3, 5,7-dihydroxylfla- vone-8-sulfonate) was synthesized and its structure was identified on the basis of NMR, FT-IR and elemental analysis. The assembly of 5,7-dihydroxylflavone-8-sulfonate with diethylamide cation afforded diethylamide 5,7-dihydroxylflavone-8-sulfonate (2, NH2(CH2CH3)2X) which was characterized by FT-IR and elemental analysis. The crystal structures of 1 and 2 were determined by X-ray single-crystal diffraction analysis. The crystal of 1 is of triclinic system, space group P1, with a = 8.5628(13), b = 12.8916(19), c = 13.562(2) A, α = 82.494(1), β = 78.601(2), γ = 84.033(2)°, C30H20Na2O15S2, Z = 2, Mr = 730.59, V = 1450.3(4) A3, Dc = 1.673 g/cm3, F(000) = 748, p = 0.295 mm^-1, the final R = 0.0641 and wR = 0.1458. The crystal of 2 crystallizes in the triclinic system, space group Pi, with a = 7.689(2), b = 11.184(3), c = 11.734(3) A, α = 74.268(3), βl = 81.751(4), γ= 87.991(3)°, C19H21NO7S, Z = 2, Mr= 407.43, V= 961.2(4) A3, Dc = 1.408 g/cm3, F(000) = 428, p = 0.210 mm^-1, the final R = 0.0484 and wR = 0.1195. In 1, the three-dimensional structure is organized into organic and inorganic regions; the flavone skeletons are stacked into organic regions by π...π staeking interactions; inorganic regions are generated by Na-O coordination bonds among sulfonate groups, coordinated water molecules and NaI. The sulfonate groups play an important role as a bridge of inorganic and organic regions. One-dimensional chain structure of 2 is extended by N-H…O hydrogen bonds and π...π stacking interactions. Furthermore, the antioxidant activity of 1 was evaluated. The scavenging activity of 1 to DPPH free radical is better than that of the parent compound chrysin. 展开更多
关键词 5 7-dihydroxylflavone-8-sulfonate spectroscopic property crystal structure DPPH free radical scavenging activity
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Effect of pH on Antioxidant and Phytochemical Activities of Mulhatti Roots (Glycyrrhiza glabra L.)
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作者 Parvesh Devi Sushila Singh +2 位作者 Seema Sangwan Promila Dalal Monika Moond 《Journal of Agricultural Science and Technology(A)》 2020年第5期276-282,共7页
Glycyrrhiza glabra L.is the most widely used herb in the ancient history of Ayurvedic medicine,as a medicinal value as well as an aromatic herb,and it is commonly known as Mulhatti.Mulhatti roots are useful for medica... Glycyrrhiza glabra L.is the most widely used herb in the ancient history of Ayurvedic medicine,as a medicinal value as well as an aromatic herb,and it is commonly known as Mulhatti.Mulhatti roots are useful for medically and are also a good source of phytoproducts and secondary metabolites present in Mulhatti roots are triterpenoid saponin,glycosides,glycyrrhizin,prenylated biaurone,licoaagrone,7-acetoxy-2-methylisoflavone,4-methylcoumarin,liqcoumarin,glycyrrhetinic acid,quercetin,liquiritigenin,isoliquiritigenin,etc.This study was carried out to study the evaluation of phenolic compounds,2,2-diphenyl-1-picrylhydrazyl(DPPH)free radical activity and general antioxidant capacity of water extracts of Mulhatti roots prepared at different pH values,namely 2,4,7 and 9.Data have shown great differences in terms of results.Most of the phenolic compounds are at pH 7(19.25),followed by pH 9(17.25),pH 2(14.62)and pH 4(8.89 mg GAE/g),respectively.Similarly,the flavonoid data also showed variations,the maximum has been present in pH 2(5.39),then pH 7(3.02),pH 9(1.79)and pH 4(1.40 mg CE/g),respectively.The value for DPPH IC50 free radical scavenging activity was the lowest at pH 7(82.22),followed by pH 2(110.40),pH 4(111.99)and pH 9(146.24μg/mL)and IC50 reference standard(ascorbic acid)was 59.52μg/mL in distilled water.The total capacity of the antioxidant was the highest at pH 2(9.93)followed by pH 4(5.54),pH 7(5.34)and pH 9(4.23 mg AAE/g).According to current research,pH 7 is the best for phytochemicals as well as antioxidants that catch harmful radicals. 展开更多
关键词 Mulhatti(Glycyrrhiza glabra L.)phytochemicals secondary metabolites phenolics FLAVONOIDS DPPH free radical scavenging activity total antioxidant capacity
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A new polyphenol, 1, 3-di-O-caffeoyl-5-O-(1-methoxyl-2-O-caffeoyl-4-maloyl)-quinic acid, isolated from cultured cells of Saussurea involucrata 被引量:2
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作者 ZOU Xiao-Wei LIU Dan +2 位作者 LIU Ya-Ping XIU Zhi-Long XIAO Hong-Bin 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2015年第4期295-298,共4页
The present study was designed to isolate the polyphenol constituents of cultured cells of Saussurea involucrata. The polyphenol type constituents were isolated using chromatography methods, and then characterized by ... The present study was designed to isolate the polyphenol constituents of cultured cells of Saussurea involucrata. The polyphenol type constituents were isolated using chromatography methods, and then characterized by spectral analysis. 1,1-Diphenyl-2-picrylhydrazyl radical 2,2-Diphenyl-1-(2,4,6-trinitrophenyl)-hydrazyl(DPPH) and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid(ABTS) free radical scavenging were assayed using Vitamin C as the positive control. One new polyphenol 18, 1, 3-di-O-caffeoyl-5-O-(1-methoxyl-2-O-caffeoyl-4-maloyl)-quinic acid, together with 17 known compounds, was isolated and characterized. In conclusion, Compound 18 was a new caffeoyl maloyl quinic acid type polyphenol and showed desired vitro anti-oxidant activity. Compounds 1–5, 9, 10, 14, 15, and 17 were isolated from cultured cells of Saussurea involucrata for the first time. 展开更多
关键词 Cultured cells Saussurea involucrata POLYPHENOL free radical scavenging activity
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The Potential Effect of Puerarin in Preventing Atherosclerosis 被引量:1
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作者 ZHU Qing-lei(朱庆磊) +7 位作者 HE Ai-xia(何爱霞) HAN Hui-rong(韩慧蓉) LU Xin-ran(吕欣然) WANG Shi-wen(王士雯) 《Chinese Journal of Integrative Medicine》 SCIE CAS 2002年第4期290-294,共5页
Objective To study the activity of Puerarin (Pue) in scavenging oxygen free radical (OFR) and its inhibitory effect on the oxidative modification of low density lipoprotein (LDL). Methods Riboflavin-light system was... Objective To study the activity of Puerarin (Pue) in scavenging oxygen free radical (OFR) and its inhibitory effect on the oxidative modification of low density lipoprotein (LDL). Methods Riboflavin-light system was used to generate superoxide anion, and Fenton reaction to generate hydroxyl free radical to study the activity of Pue in scavenging OFR. Hydrogen peroxide-induced hemolysis was used to study the effect of Pue on erythrocyte hemolysis and malondialdehyde (MDA) production. And ultraviolet ray and cupric sulfate were used to cause the oxidative modification of LDL for studying the inhibitory effect of Pue on LDL oxidative modification. Results (1) Pue could, at concentration of 0. 01 – 1.0 mmol/L, scavenge superoxide anion radical and at concentration of 7.5–75μmol/L scavenge hydroxyl radical in a concentration dependent manner. (2) Pue could, at concentration of 0.1–10 mmol/L, inhibit significantly oxidative hemolysis and MDA production of erythrocyte induced by hydrogen peroxide. (3) Pue of 0.01–1.0 mmol/L could inhibit the oxidative modification of LDL in a concentration dependent manner. Conclusion Pue has an anti-peroxidation effect and shows a potential effect in preventing atherosclerosis. 展开更多
关键词 PUERARIN ANTIOXIDATION active oxygen free radical low density lipoprotein oxidative modification
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Evaluation of antioxidant activities of Hippophae rhamnoides Linn leaves extracts 被引量:1
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作者 Javid Ali Bashir Ahmad 《Journal of Coastal Life Medicine》 2015年第5期379-381,共3页
Objective:To investigate the antioxidant activity of aqueous,methanol,ethanol,acetone,ethyl acetate,chloroform and n-hexane extracts of Hippophae rhamnoides(H.rhamnoides)leaves.Methods:Antioxidant activity was evaluat... Objective:To investigate the antioxidant activity of aqueous,methanol,ethanol,acetone,ethyl acetate,chloroform and n-hexane extracts of Hippophae rhamnoides(H.rhamnoides)leaves.Methods:Antioxidant activity was evaluated by using in-vitro antioxidant assays model 1,1’-diphenyl-2-picrylhydrazyl radical-scavenging activity.The antioxidant activities were compared with standard antioxidant agents such as ascorbic acid.Results:The antioxidant activities(%inhibition)of all the tested extracts were increased in the order i.e.menthol>ethanol>aqueous>acetone>chloroform>ethyl acetate>n-hexane.The methanol extract EC_(50)(μg/mL)value was compatible with vitamin C(standard).The antioxidant activity of H.rhamnoides leaves extracts increased in a dose dependent manner.Conclusions:It was observed that H.rhamnoides was a potential resource of antioxidants and thus could put off numerous radical linked diseases. 展开更多
关键词 SEABUCKTHORN Solvent extracts free radical scavenging activities Vitamin C EC_(50)
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Preparation and Characterization of Two Wood Vinegars Obtained from Hull of Spina Date Seed and Shell of Peanut
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作者 LI Zhanchao ZHANG Zhiquan +5 位作者 WU Lijie WANG Jichang LIU Zhenheng ZHANG Zhongwei ZHANG Hanqi WANG Ziming 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2017年第3期348-353,共6页
Two new kinds of wood vinegars(WVs) from the hull of spina date seed(HSDS) and the shell of peanut(PS) were prepared. 32 Major components in the two kinds of WVs were identified and determined by gas chro- matog... Two new kinds of wood vinegars(WVs) from the hull of spina date seed(HSDS) and the shell of peanut(PS) were prepared. 32 Major components in the two kinds of WVs were identified and determined by gas chro- matograph-mass spectrometery. The total phenolic content was determined and the antioxidant activity of the WV was measured. The total phenolic contents of PSWV and HSDSWV were 75.9 and 98.1 rag/L, respectively, when they were expressed as catechol equivalents. In 1,1-diphenyl-2-picrylhydrazyl assay, free radical scavenging activity of HSDSWV was also superior than that of PSWV. In addition, the antioxidant activities of the two kind of WVs exhibited a good positive correlation with total phenolic content, and the linear correlation coefficients ranged from 0.9594 to 0.9970. The two kind of WVs could be used in the fields of food and medicine due to their powerful antioxidant activities. 展开更多
关键词 Hull of spina date seed Shell of peanut Wood vinegar Total phenolic content Antioxidant activity free radical scavenging activity
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Reaction mechanism of dicofol removal by cellulase
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作者 Ziyuan Wang Ting Yang +2 位作者 Zihan Zhai Boya Zhang Jianbo Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第10期22-28,共7页
It remains unclear whether dicofol should be defined as a persistent organic pollutant. Its environmental persistence has gained attention. This study focused on its degradation by cellulase. Cellulase was separated u... It remains unclear whether dicofol should be defined as a persistent organic pollutant. Its environmental persistence has gained attention. This study focused on its degradation by cellulase. Cellulase was separated using a gel chromatogram, and its degradation activity towards dicofol involved its endoglucanase activity. By analyzing the kinetic parameters of cellulase reacting with mixed substrates, it was shown that cellulase reacted on dicofol and carboxyl methyl cellulose through two different active centers. Thus, the degradation of dicofol was shown to be an oxidative process by cellulase. Next, by comparing the impacts of tert-butyl alcohol(a typical OH free-radical inhibitor) on the removal efficiencies of dicofol under both cellulase and Fenton reagent systems, it was shown that the removal of dicofol was initiated by OH free radicals produced by cellulase. Finally, 4,4′-dichlorodibenzophenone and chloride were detected using gas chromatography mass spectrometry and ion chromatography analysis, which supported our hypothesis. The reaction mechanism was analyzed and involved an attack by OH free radicals at the orthocarbon of dicofol, resulting in the degradation product 4,4′-dichloro-dibenzophenone. 展开更多
关键词 Dicofol Cellulase Endo-glucanases activity Oxidative degradation OH free radical
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