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Changes of free radicals and digestive enzymes in saliva in cases with deficiency inspleen-yin syndrome 被引量:16
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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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Effect of Nonenzymatic Antioxidants on Sperm Motility and Survival Relative to Free Radicals and Antioxidant Enzymes of Chilled-Stored Ram Semen 被引量:1
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作者 Moustafa M. Zeitoun Mona A. Al-Damegh 《Open Journal of Animal Sciences》 2015年第1期50-58,共9页
The effect of inclusion of three antioxidants (Vitamin E, cysteine and glutathione) in ram semen extender on the release of antioxidant enzymes and free radicals was studied. A 3 × 3 factorial experiment was cond... The effect of inclusion of three antioxidants (Vitamin E, cysteine and glutathione) in ram semen extender on the release of antioxidant enzymes and free radicals was studied. A 3 × 3 factorial experiment was conducted to test effects of supplementing ram semen extender with Vitamin E (1, 5 and 10 IU), cysteine (1, 5 and 10 mM) or glutathione (0.5, 1 and 2 mM) on the sperm survival and release of superoxide dismutase (SOD), glutathione peroxidase (GPX) and thiobarbituric acid reactive substances (TBARS). Eighty ejaculates of eight fertile Najdi rams were collected, assessed for the gross examination and the good ejaculates (≥90% motility) were pooled and sperm count was assessed. Therefore ten extenders;control (C) and 9 treated (C plus antioxidant) were tested. Extended semen was stored at 5°C for 96 h, examined for motility and survival and sperm cells were separated from plasma, sonicated, homogenized and exposed to the determinations of SOD, GPX and TBARS. The highest sperm survival was found in diluents containing 5 IU Vitamin E/ml, 1 and 2 mM glutathione (55.5% survival), while the lowest survival was found in 10 mM cysteine (11.1%). TBARS concentration was highest (P < 0.05) in control than other treatments, however, Vitamin E and glutathione exhibited low values. Contrariwise, activities of SOD and GPX increased (P < 0.05) within sperm cells and seminal plasma in diluents containing 5 IU E, 1 mM and 2 mM glutathione. The enzymatic activities were generally higher in seminal plasma than in sperm cells. It was concluded that supplementing ram semen extender during chilled storage with 5 IU Vitamin E per ml or 1 - 2 mM glutathione enhanced sperm survival and reduced free radicals. 展开更多
关键词 Ram SEMEN Storage Free radicalS ANTIOXIDANT enzymeS
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Super-exchange and Exchange-Enhanced Reactivity in Fe_(4)S_(4)-Mediated Activation of SAM by Radical SAM Enzymes
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作者 Jian-qiang Feng Bin-ju Wang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2021年第5期532-540,I0002,共10页
[4Fe-4S]-dependent radical S-adenosylmethionine(SAM)proteins are a superfamily of oxidoreductases that can catalyze a series of challenging transformations using the common 5-d Ado radical intermediate.Although the st... [4Fe-4S]-dependent radical S-adenosylmethionine(SAM)proteins are a superfamily of oxidoreductases that can catalyze a series of challenging transformations using the common 5-d Ado radical intermediate.Although the structures and functions of radical SAM enzymes have been extensively studied,the electronic state-dependent reactions of the[4Fe-4S]clusters in these enzymes are still elusive.Herein we performed QM/MM calculations to elucidate the electronic state-dependent reactivity of the[4Fe-4S]cluster in pyruvate-formate lyase activating enzyme.Our calculations show that the electronic statedependent SAM activation by the[4Fe-4S]clusters in radical SAM enzyme is determined by both the super-exchange and exchange-enhanced reactivities.The super-exchange coupling in the[4Fe-4S]cluster favors the antiferromagnetic coupling between two neighbouring pairs,which results in theα-electron rather than theβ-electron donation from the[4Fe-4S]^(1+)cluster toward the SAM activation.Meanwhile,in the most favorable electronic state for the reductive cleavage of S-C5′,Fe4 would donate itsα-electron to gain the maximum exchange interactions in the Fe4-block.Such super-exchange and exchange-enhanced reactivity could be the general principles for reactivities of[4Fe-4S]cluster in RS enzymes. 展开更多
关键词 QM/MM Iron-sulfur protein Electron transfer Super-exchange Exchange-enhanced reactivity radical SAM enzyme
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Effects of total soy saponins on free radicals in the quadriceps femoris,serum testosterone,LDH,and BUN of exhausted rats 被引量:8
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作者 Zhigang Liu Ruixin Nie +3 位作者 Yun Liu Zhouhong Li Chenxi Yang Zhengying Xiong 《Journal of Sport and Health Science》 SCIE 2017年第3期359-364,共6页
Purpose:The aim of this study was to investigate the impact of total soy saponins(TS) on the free radical metabolism from the quadriceps femoris muscle,serum testosterone,lactate dehydrogenase(LDH),and blood urea nitr... Purpose:The aim of this study was to investigate the impact of total soy saponins(TS) on the free radical metabolism from the quadriceps femoris muscle,serum testosterone,lactate dehydrogenase(LDH),and blood urea nitrogen(BUN) in rats exercised to exhaustion.Methods:A one-time exhausted treadmill exercise session was used.Sprague-Dawley rats were divided into 4 groups:a control group—animals receiving no TS and no exercise(NTSNE),animals receiving TS but no exercise group(TSNE),animals receiving no TS but exercised to exhaustion group(NTSE),and animals receiving TS and exercised to exhaustion group(TSE).The TSNE and TSE groups were fed TS at a dosage of 20 mg/kg body weight once per day for 2 weeks.The NTSE group was given a placebo,and the NTSNE group was not given any treatment.The NTSE and TSE groups were exercised at speed of 30 m/min on treadmill until exhausted.The exercise time and exercise distance were recorded when the rats became exhausted and the rats were then decapitated and anatomized immediately.A 10% homogenate of the quadriceps femoris tissue was prepared.The levels of superoxide dismutase(SOD),catalase(CAT),malondialdehyde(MDA),glutathione peroxidase(GSH-Px),glutathione reductase(GR),reduced glutathione(GSH),total antioxidant capacity(T-AOC),LDH,BUN,and serum testosterone were tested.Results:TS significantly increased the exercise time to exhaustion by 20.62%(p < 0.05).The MDA levels were decreased significantly in the TSNE group than in NTSNE group(p < 0.05);the T-AOC levels increased significantly in the TSNE group than in the other 3 groups(p < 0.01,p < 0.05,p < 0.05).The LDH activity significantly increased in the NTSE group than in TSNE group(p < 0.05).The BUN levels significantly increased in the NTSE group than in the other 3 groups(p < 0.01,p < 0.01,p < 0.05),and significantly increased in the TSE group than in NTSNE and TSNE groups(both p < 0.01).The serum testosterone levels increased significantly in the TSNE group than in the other 3 groups(all p < 0.01).SOD,CAT,GSH-Px,GR,and GSH were not statistically different among the groups.Conclusion:TS can significantly improve the exercised rats' serum testosterone level and antioxidant activity in their quadriceps femoris to varying degrees,decrease MDA and serum LDH and BUN levels,increase the exercise time,and delay the occurrence of the fatigue. 展开更多
关键词 Exercised rat Free radical Quadriceps femoris Serum enzymes TESTOSTERONE Total soy saponins
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Treating ballast water with hydroxyl radical on introduced organisms 被引量:3
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作者 张芝涛 白敏菂 +3 位作者 肖宇 白敏冬 杨波 白希尧 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2006年第2期161-167,共7页
With physical method of micro-gap gas discharge, a large amount of hydroxyl radical can be produced in 20t/h pilot-scale system using the ionization of 02 and H2O. In this paper, the effect of biochemistry of hydroxyl... With physical method of micro-gap gas discharge, a large amount of hydroxyl radical can be produced in 20t/h pilot-scale system using the ionization of 02 and H2O. In this paper, the effect of biochemistry of hydroxyl radicals on introduced organisms in ballast water was experimentally investigated. The results indicate that the contents of chlorophyl-a, chlorophyl-b, chlorophyl-c and carotenoid are decreased by 35%-4% within 8.0s and further to the lowest limit of test 5 minutes. In addition, the main reasons of cell death are the lipid peroxidation, the strong destruction to the monose, amylose, protein, DNA and RNA of cell, and damage in CAT, POD and SOD of antioxidant enzyme system. 展开更多
关键词 hydroxyl radical introduced organisms photosynthesis pigment lipid peroxidation basic life substances antioxidant enzyme ballast water
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Lipase Immobilization onto the Surface of PGMA-b-PDMAEMA-grafted Magnetic Nanoparticles Prepared via Atom Transfer Radical Polymerization 被引量:1
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作者 王静云 姬芳玲 +3 位作者 邢继双 崔双 包永明 郝文博 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第Z1期1333-1339,共7页
A block copolymer of 2-dimethylaminoethyl methacrylate(DMAEMA) and glycidyl methacrylate(GMA)was grafted onto the surface of magnetic nanoparticles(Fe3O4) via atom transfer radical polymerization.The resultant PGMA-b-... A block copolymer of 2-dimethylaminoethyl methacrylate(DMAEMA) and glycidyl methacrylate(GMA)was grafted onto the surface of magnetic nanoparticles(Fe3O4) via atom transfer radical polymerization.The resultant PGMA-b-PDMAEMA-grafted-Fe3O4 magnetic nanoparticles with amino and epoxy groups were characterized by Fourier transform infrared spectroscopy, powder X-ray diffraction, thermo-gravimetric analysis, and scanning electron microscopy. Lipase from Burkholderia cepacia was successfully immobilized onto the magnetic nanoparticles by physical adsorption and covalent bonding. The immobilization capacity of the magnetic particles is 0.5 mg lipase per mg support, with an activity recovery of up to 43.1% under the optimum immobilization condition. Biochemical characterization shows that the immobilized lipase exhibits improved thermal stability, good tolerance to organic solvents with high lg P, and higher p H stability than the free lipase at p H 9.0. After six consecutive cycles, the residual activity of the immobilized lipase is still over55% of its initial activity. 展开更多
关键词 enzyme Atom transfer radical polymerization IMMOBILIZED LIPASE Fe3O4nanoparticles
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Levels of antioxidant enzymes and alkaline protease from pulp and peel of sunflower 被引量:1
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作者 Wesen Adel Mehdi Faridah Yusof +2 位作者 Layla O.Farhan Atheer Awad Mehde Raha Ahmed Raus 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2017年第6期533-537,共5页
Objective:The activity of enzymes participating in the systems of antioxidant protection was assayed in the peel and pulp of sunflower.The essential roles of proteases in food stimulate research to find other sources ... Objective:The activity of enzymes participating in the systems of antioxidant protection was assayed in the peel and pulp of sunflower.The essential roles of proteases in food stimulate research to find other sources of the enzyme especially from non-conventional sources.In the present work,we study several biochemical parameters in the pulp and peel of sunflower.Methods:Pulp and peel of sunflower was extracted,antioxidant enzymes and nonenzymatic antioxidant were measured.Alkaline protease was measured and purified from pulp in sunflower.Results:High carbohydrate concentration,beta-carotene,catalase and ascorbate peroxidase activities,free radical scavenging capacity and free flavonoid content were observed in the peel of sunflower.Whereas,MDA and ceruloplasmin activities were high in the pulp of sunflower.Conclusions:The present study concluded that peel in sunflower are strong radical scavengers and can be considered as good sources of natural antioxidants for medicinal and commercial uses.Further analysis showed that protease activity was a significantly high in the pulp compared to the peel. 展开更多
关键词 Pulp sunflower Antioxidant enzymes Free radical scavenging capacity Free flavonoid content Alkaline protease
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一种玫瑰本草酵素的制备及其抗皮肤衰老功能的研究
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作者 惠美星 宋虹 +3 位作者 余萍 闵祥博 矫艳平 赵迪 《生物加工过程》 CAS 2024年第1期99-105,共7页
以重瓣红玫瑰、桑椹和玫瑰茄为原料,利用植物乳植杆菌、罗伊氏粘液乳杆菌和鼠李糖乳酪杆菌发酵制备玫瑰本草酵素。为了探究玫瑰本草酵素发酵过程中抗氧化活性的变化规律及其对肤质的改善功效,首先对其理化成分含量进行测定,接着对其在... 以重瓣红玫瑰、桑椹和玫瑰茄为原料,利用植物乳植杆菌、罗伊氏粘液乳杆菌和鼠李糖乳酪杆菌发酵制备玫瑰本草酵素。为了探究玫瑰本草酵素发酵过程中抗氧化活性的变化规律及其对肤质的改善功效,首先对其理化成分含量进行测定,接着对其在发酵过程中的抗氧化能力及其酶活进行分析,最后利用人群试验评价该酵素对志愿者的肤色、淡斑、肌肤纹理及肌肤弹性等指标的影响。结果表明:该酵素的多酚、前花青素、乳酸、γ-氨基丁酸、游离氨基酸含量及超氧化物歧化酶(SOD)活性分别为38 mg/g、244 mg/kg、5.5×10~3 mg/kg、562 mg/kg、0.68 mg/g、33.2 U/mL。发酵过程中,该酵素对1,1-二苯基-2-三硝基肼自由基(DPPH·)和羟基自由基(·OH)的清除效率与SOD酶活和总酚含量变化呈正相关;同时,SOD酶活和总酚含量水平与该酵素发酵过程中纤维素酶和果胶酶的酶活密切相关。通过30 d人群实验发现,服用该酵素可有效改善肤色及淡斑。本研究为开发一种新型玫瑰本草酵素提供了一定的理论依据。 展开更多
关键词 玫瑰本草酵素 植物乳植杆菌 罗伊氏粘液乳杆菌 鼠李糖乳酪杆菌 抗氧化 清除自由基
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胃癌根治术患者麻醉中应用右美托咪定对脑电双频指数、红细胞代谢限速酶的影响
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作者 揭瑶 何文 《赣南医科大学学报》 2024年第11期1132-1136,共5页
目的:探讨右美托咪定(Dexmedetomidine,Dex)对胃癌根治术患者脑电双频指数(Bispectral index,BIS)、红细胞糖代谢限速酶水平的影响。方法:选取我院胃肠外科收治的拟行腹腔镜下胃癌根治手术患者120例,采用前瞻性随机研究分为Dex组(术前10... 目的:探讨右美托咪定(Dexmedetomidine,Dex)对胃癌根治术患者脑电双频指数(Bispectral index,BIS)、红细胞糖代谢限速酶水平的影响。方法:选取我院胃肠外科收治的拟行腹腔镜下胃癌根治手术患者120例,采用前瞻性随机研究分为Dex组(术前10 min给予Dex 0.5μg·kg^(-1),术中给予Dex 0.3μg·kg^(-1)·h^(-1)维持)和对照组(术前给予等量生理盐水),每组60例,2组患者其余麻醉诱导药物及术中给予药物相同,对比2组患者麻醉中不同时间点的平均动脉压(Mean arterial pressure,MAP)、心率(Heart rate,HR)、BIS监测值、手术前后红细胞磷酸果糖激酶(Phosphofructokinase,PFK)、葡萄糖-6-磷酸脱氢酶(Glucose-6-phosphate dehydrogenase,G-6-PD)、醛糖还原酶(Aldose reductase,AR)的活性以及血清皮质醇(Cortisol,Cor)、肾上腺素(Epinephrine,E)、促肾上腺皮质激素(Adrenocorticotropic hormone,ACTH)水平。结果:2组患者麻醉时间、手术时间比较差异无统计学意义(P>0.05)。MAP、HR水平的组别、时间、交互作用比较,差异有统计学意义(P<0.05)。BIS值的组别、时间、交互作用比较,差异无统计学意义(P>0.05)。Dex组患者MAP、HR水平优于对照组,差异有统计学意义(P<0.05)。术前,2组患者红细胞代谢限速酶水平比较,差异无统计学意义(P>0.05);术后24 h,Dex组PFK活性值高于对照组(P<0.05),G-6-PD、AR测定值均低于对照组(P<0.05)。术前,2组患者血清应激指标比较,差异无统计学意义(P>0.05);术后24 h,Dex组Cor、E、ACTH均低于对照组(P<0.05)。2组患者躁动、恶心呕吐、尿潴留、嗜睡发生率比较,差异无统计学意义(P>0.05)。结论:胃癌根治术患者给予Dex,有利于维持患者血流动力学稳定,改善红细胞糖代谢状态,降低手术引起的应激反应。 展开更多
关键词 右美托咪定 胃肿瘤根治术 脑电双频指数 红细胞代谢限速酶
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离子注入水稻种子萌发过程中的自由基和SOD酶研究 被引量:10
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作者 吴跃进 吴敬德 +4 位作者 刘贵富 吴家道 余增亮 邓建国 何建军 《作物学报》 CAS CSCD 北大核心 1996年第3期320-324,共5页
用能量30Kw_1剂量6×10^(16)N^+/cm^2的氮离子束辐照水稻早籼品种广陆矮4号,用ESR波谱术和氮蓝四唑(NBT)还原法测定水稻种子萌发过程中的自由基和SOD酶的变化.在室温和低温下测定离子注入水稻干种子的ESR谱,结果表明:辐照后的水稻... 用能量30Kw_1剂量6×10^(16)N^+/cm^2的氮离子束辐照水稻早籼品种广陆矮4号,用ESR波谱术和氮蓝四唑(NBT)还原法测定水稻种子萌发过程中的自由基和SOD酶的变化.在室温和低温下测定离子注入水稻干种子的ESR谱,结果表明:辐照后的水稻干种子有较高的自由基产额;低温测定ESR波谱显现出二条谱峰,这为糖和蛋白质在电离辐射作用下产生的特征峰.种子萌发过程中的自由基变化是在种子吸水8小时时自由基浓度锐减,16小时降至最低点;自由基清除酶之一SOD酶,随着吸水时间的增加,酶活性逐渐增加,SOD酶的清除作用主要表现在生物体内源自由基的清除.最后生物体内自由基和SOD酶形成动态平衡. 展开更多
关键词 自由基 SOD 离子束辐照 水稻 种子萌发
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酪蛋白酶解物体外抗氧化作用的研究 被引量:27
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作者 胡文琴 王恬 +1 位作者 霍永久 张金霞 《食品科学》 EI CAS CSCD 北大核心 2004年第4期158-162,共5页
采用正交试验设计,以羟自由基清除率为衡量指标,筛选三种蛋白酶水解酪蛋白的最佳条件。试验结果表明,木瓜蛋白酶最佳酶解条件为pH7.5,酶浓度8%,温度45℃,反应时间90min,羟自由基清除率为71.28%,与同浓度维生素C、维生素E的清除率差异均... 采用正交试验设计,以羟自由基清除率为衡量指标,筛选三种蛋白酶水解酪蛋白的最佳条件。试验结果表明,木瓜蛋白酶最佳酶解条件为pH7.5,酶浓度8%,温度45℃,反应时间90min,羟自由基清除率为71.28%,与同浓度维生素C、维生素E的清除率差异均不显著(p>0.05);枯草杆菌蛋白酶(As1.398)最佳酶解条件为pH7.0,酶浓度2%,温度50℃,反应时间90min,羟自由基清除率为68.60%;胃蛋白酶最佳酶解条件为pH1.4,酶浓度6%,温度37℃,反应时间30min,羟自由基清除率为66.53%。试验发现,不同的酪蛋白酶解物都有抗脂质过氧化作用,最大抑制率为59.28%。 展开更多
关键词 酪蛋白 酶解物 抗氧化作用 羟自由基 清除作用
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大豆分离蛋白酶解物清除羟自由基作用的研究 被引量:130
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作者 陈美珍 余杰 郭慧敏 《食品科学》 EI CAS CSCD 北大核心 2002年第1期43-47,共5页
用比色法测定了大豆分离蛋白(SPI)酶解物对羟自由基的清除作用。结果表明,SPI酶解物对Fenton体系产生的·OH自由基有清除活性。SPI经木瓜蛋白酶水解15min,其酶解物清除能力已达最大值,为56.5%;经SephadexG-50凝胶柱分离,所得肽段各... 用比色法测定了大豆分离蛋白(SPI)酶解物对羟自由基的清除作用。结果表明,SPI酶解物对Fenton体系产生的·OH自由基有清除活性。SPI经木瓜蛋白酶水解15min,其酶解物清除能力已达最大值,为56.5%;经SephadexG-50凝胶柱分离,所得肽段各组分间的清除活性存在明显差异;用SDS-PAGE凝胶电泳测定各组分的分子量,结果显示分子量在11.355KD~5.154KD的肽段清除能力最强,达60.4%。 展开更多
关键词 大豆分离蛋白 酶解物 羟自由基 清除能力 大豆多肽 抗氧化活性
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土壤渍涝对芝麻根系生长及抗氧化物酶活性的影响 被引量:33
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作者 刘华山 孟凡庭 +3 位作者 杨青华 韩锦峰 王春莉 顿文涛 《植物生理学通讯》 CSCD 北大核心 2005年第1期45-47,共3页
在渍水条件下芝麻根系生长速度下降,干物质积累减少,根系的抗氧化物酶——超氧物歧化酶(SOD)、过氧化氢酶(CAT)和过氧化物酶(POD)活性先增后下降,POD活性下降较缓慢,超氧自由由基(O-2·)产生速率和丙二醛(MDA)含量随淹水时间的延长... 在渍水条件下芝麻根系生长速度下降,干物质积累减少,根系的抗氧化物酶——超氧物歧化酶(SOD)、过氧化氢酶(CAT)和过氧化物酶(POD)活性先增后下降,POD活性下降较缓慢,超氧自由由基(O-2·)产生速率和丙二醛(MDA)含量随淹水时间的延长而升高。 展开更多
关键词 根系生长 芝麻 渍涝 POD活性 产生速率 淹水时间 渍水 过氧化氢酶(CAT) 过氧化物酶(POD) 超氧物歧化酶
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不同提取方法对灵芝多糖性质的影响研究 被引量:28
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作者 游丽君 冯梦莹 +3 位作者 刘钧发 赵强忠 罗维 赵谋明 《现代食品科技》 EI CAS 北大核心 2013年第6期1207-1212,共6页
本研究比较了超声波法(UP)、超声波结合纤维素酶法(UCP)、超声波结合胰酶法(UPP)、传统热水提取法(TP)四种方法提取灵芝多糖的性质区别。结果表明采用超声波结合胰酶法提取多糖得率最高,可达4.93%,比传统水提法的多糖得率高1.58倍。相... 本研究比较了超声波法(UP)、超声波结合纤维素酶法(UCP)、超声波结合胰酶法(UPP)、传统热水提取法(TP)四种方法提取灵芝多糖的性质区别。结果表明采用超声波结合胰酶法提取多糖得率最高,可达4.93%,比传统水提法的多糖得率高1.58倍。相比传统水提法所得多糖的分子量,超声处理可显著降低多糖分子量,超声结合酶法提取对多糖的降解作用更加显著,其中胰酶效果最为明显,可将多糖分子量降至5 kDa以下。此外,采用超声波结合胰酶法提取的多糖也具有较好的抗氧化活性,其还原力在浓度1.0 mg/mL时为1.408,羟自由基清除能力在浓度2.0 mg/mL时为50.08%,ABTS+清除能力在浓度1.0 mg/mL时为82.5%,氧自由基吸收能力(ORAC)值可达2484.14μmolTrolox/g。 展开更多
关键词 灵芝多糖 超声 抗氧化 自由基
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酵母铬对热应激肉鸡抗氧化性能的影响 被引量:19
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作者 张彩虹 姜建阳 +2 位作者 任慧英 朱风华 李文立 《动物营养学报》 CAS CSCD 北大核心 2009年第5期741-746,共6页
本试验旨在研究酵母铬不同添加水平对热应激肉鸡体内抗氧化性能的影响。选用14日龄AA肉仔鸡216只,随机分为6个处理,在基础日粮中分别添加铬0(对照组)、1.0、2.0、3.0、4.0和5.0 mg/kg,每组设3个重复,每重复12只鸡,试验期4周,在热应激条... 本试验旨在研究酵母铬不同添加水平对热应激肉鸡体内抗氧化性能的影响。选用14日龄AA肉仔鸡216只,随机分为6个处理,在基础日粮中分别添加铬0(对照组)、1.0、2.0、3.0、4.0和5.0 mg/kg,每组设3个重复,每重复12只鸡,试验期4周,在热应激条件下测定了28和42日龄肉鸡血清和肝脏组织中抑制羟自由基(·OH)能力、抗超氧阴离子自由基(O2 -·)活性、MDA含量、GSH-Px、T-SOD、CAT活性和T-AOC。试验结果表明:3.0、4.0 mg/kg铬添加水平能够显著增强热应激肉鸡血清(28日龄)和肝脏(42日龄)中抑制羟自由基能力(P<0.05),提高血清(28和42日龄)和肝脏组织(42日龄)中抗超氧阴离子自由基活性(P<0.05);减少血清(28和42日龄)和肝脏(28日龄)中MDA生成(P<0.05);显著提高血清(28和42日龄)和肝脏组织(28和42日龄)中GSH-Px活性和T-AOC(P<0.05);极显著提高肝脏组织(28和42日龄)中T-SOD活性(P<0.01);并能提高血清(42日龄)CAT活性(P<0.05)。结果显示,日粮添加酵母铬可以提高热应激肉鸡血清和肝脏中抑制羟自由基(·OH)能力、抗超氧阴离子自由基(O。·)活性,减少MDA生成,并能提高血清和肝脏组织中GSH-Px、T-SOD、CAT活性和T-AOC,日粮中适宜的铬添加水平为3.0 mg/kg。 展开更多
关键词 酵母铬 热应激 肉鸡 自由基 抗氧化酶
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二硫化碳对大鼠睾丸组织氧自由基及抗氧化水平的影响 被引量:12
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作者 邓菁 陈国元 +6 位作者 季佳佳 谭皓 虎凤仙 柴莲花 刘卫东 刘四海 易元川 《华中科技大学学报(医学版)》 CAS CSCD 北大核心 2006年第2期228-230,共3页
目的探讨二硫化碳(CS2)对雄性大鼠睾丸组织氧自由基及抗氧化水平的影响。方法取健康Wistar雄性大鼠24只,随机将其分为4组,以不同浓度CS2(0、50、2501、250 mg/m3)静式吸入染毒,共持续10周。染毒结束后,处死动物取睾丸制备组织匀浆,分别... 目的探讨二硫化碳(CS2)对雄性大鼠睾丸组织氧自由基及抗氧化水平的影响。方法取健康Wistar雄性大鼠24只,随机将其分为4组,以不同浓度CS2(0、50、2501、250 mg/m3)静式吸入染毒,共持续10周。染毒结束后,处死动物取睾丸制备组织匀浆,分别测定组织中超氧化物歧化酶(SOD)、丙二醛(MDA)、谷胱甘肽-S-转移酶(GST)、谷胱甘肽(GSH)、谷胱甘肽过氧化物酶(GSH-px)、一氧化氮(NO)、一氧化氮合酶(NOS)及诱导型一氧化氮合酶(iNOS)含量。结果与对照组比较,各染毒组睾丸组织中SOD活力下降,MDA含量上升,GSH含量及GST、GSH-px活力下降,NO含量及NOSi、NOS活力均下降。结论CS2染毒雄性大鼠睾丸组织的氧自由基增加,抗氧化能力减弱以及NO合成受抑制,与CS2所致雄性生殖功能障碍有关。 展开更多
关键词 二硫化碳 睾丸 氧自由基 抗氧化酶
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苋菜种子萌发过程的超微弱发光及其机理研究 被引量:14
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作者 侯仙慧 廖祥儒 +4 位作者 李颖 张晓晴 卜文娟 贾燕 李光 《种子》 CSCD 北大核心 2004年第7期24-27,共4页
利用 BPCL- 4型超微弱发光测量仪测得光照与黑暗条件培养下 ,红、白两种苋菜种子萌发过程中的超微弱发光(UBE)情况 ,并测定了与氧自由基代谢密切相关的五种酶的活性 ,结果表明超氧化物歧化酶 (SOD)活性与 UBE变化趋势呈显著正相关 ,而... 利用 BPCL- 4型超微弱发光测量仪测得光照与黑暗条件培养下 ,红、白两种苋菜种子萌发过程中的超微弱发光(UBE)情况 ,并测定了与氧自由基代谢密切相关的五种酶的活性 ,结果表明超氧化物歧化酶 (SOD)活性与 UBE变化趋势呈显著正相关 ,而过氧化氢酶 (CAT) 展开更多
关键词 苋菜 种子萌发 超微弱发光 作用机理 氧自由基代谢 超氧化物歧化酶 过氧化氢酶 酶活性
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复方丹参方抗大鼠心肌缺血作用研究 被引量:27
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作者 高秀梅 王怡 +5 位作者 商洪才 张萌 郭利平 宫涛 赵亚利 张伯礼 《天津中医药》 CAS 2003年第1期23-25,共3页
[目的]复方丹参方不同工艺提取物心肌缺血差异。[方法]采用冠脉结扎的大鼠模型 ,以心肌缺血面积、心肌酶、自由基作为药效指标 ,观察复方丹参片和复方丹参滴丸抗心肌缺血作用。[结果]大鼠结扎冠脉前降支21h后坏死面积高达60 35 % ,LDH... [目的]复方丹参方不同工艺提取物心肌缺血差异。[方法]采用冠脉结扎的大鼠模型 ,以心肌缺血面积、心肌酶、自由基作为药效指标 ,观察复方丹参片和复方丹参滴丸抗心肌缺血作用。[结果]大鼠结扎冠脉前降支21h后坏死面积高达60 35 % ,LDH含量为 (2552 7±268 3)U/L ,明显高于对照组和假手术组 ,P<0.01 ;用药后不同剂量复方丹参片 (剂量分别为1 04、2 08、4 13g/kg 生药量 )均可使坏死面积缩小 ,LDH含量下降 ,P<0.01 ,滴丸组优于同等生药量的片剂组 ;冠脉结扎21h后ST段下降 ,下降的波幅以用药组明显 ,显著高于模型组 ,P<0.05。冠脉结扎后血浆SOD含量也下降 ,使用复方丹参片、复方丹参滴丸、消心痛后其含量均升高 ,与模型组相比有显著差异 ,但其中以片剂2.08g/kg组为优。[结论]复方丹参方两种工艺提取物均具有抗心肌缺血作用。 展开更多
关键词 复方丹参 心肌缺血 心肌酶 心肌缺血面积 自由基 手术 大鼠
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蛹虫草降血糖作用及其机制研究 被引量:35
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作者 徐雷雷 王静凤 +3 位作者 唐筱 王玉明 傅佳 薛长湖 《中国药理学通报》 CAS CSCD 北大核心 2011年第9期1331-1332,共2页
蛹虫草主要含有虫草素、虫草酸、虫草多糖、SOD等活性物质,具有抗肿瘤、抗炎、镇静催眠、提高机体免疫力、防止衰老、抗氧化等功效。已有研究报道表明,蛹虫草活性提取物具有良好的降血糖作用,但对蛹虫草单用降血糖及其作用机制的研... 蛹虫草主要含有虫草素、虫草酸、虫草多糖、SOD等活性物质,具有抗肿瘤、抗炎、镇静催眠、提高机体免疫力、防止衰老、抗氧化等功效。已有研究报道表明,蛹虫草活性提取物具有良好的降血糖作用,但对蛹虫草单用降血糖及其作用机制的研究少见报道。本实验以蛹虫草为研究对象,观察其对糖尿病大鼠的降血糖作用并对其作用机制进行探讨,以期为蛹虫草的高值化利用提供理论依据。 展开更多
关键词 关键词:蛹虫草 糖尿病 空腹血糖 抗氧化酶 自由基 显微 结构 胰岛Β细胞
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UV-B辐射增强对红松幼苗针叶脂质过氧化及抗氧化系统的影响 被引量:17
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作者 魏晓雪 于景华 +3 位作者 李德文 佟璐 庞海河 祖元刚 《林业科学》 EI CAS CSCD 北大核心 2011年第5期54-59,共6页
以盆栽3年生红松实生苗为材料,分为CK(对照)、T1(+3.25μW·cm-2UV-B辐射)、T2(+6.51μW·cm-2UV-B辐射)及T3(+9.76μW·cm-2UV-B辐射)4个处理,研究环境UV-B辐射增强对红松叶片自由基含量、脂质过氧化程度及抗氧化系统的影... 以盆栽3年生红松实生苗为材料,分为CK(对照)、T1(+3.25μW·cm-2UV-B辐射)、T2(+6.51μW·cm-2UV-B辐射)及T3(+9.76μW·cm-2UV-B辐射)4个处理,研究环境UV-B辐射增强对红松叶片自由基含量、脂质过氧化程度及抗氧化系统的影响。结果表明:UV-B辐射增强显著提高红松针叶内羟基自由基(·OH)、过氧化氢自由基(H2O2)和MDA含量(P<0.05),T3处理下叶片的H2O2(149.05mmol·g-1)和MDA(12.56μmol·g-1)含量最高;UV-B辐射增强诱导过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)和超氧化物歧化酶(SOD)活性升高,显著降低过氧化物酶(POD)活性(P<0.05);抗氧化物质中可溶性蛋白含量随UV-B胁迫程度加强而显著增加(CK为0.17mg·g-1,T3处理为0.26mg·g-1),而各UV-B辐射增强处理均降低了类胡萝卜素和类黄酮含量。各生理指标相关分析结果表明:红松针叶内可溶性蛋白含量与自由基、MDA含量间存在极显著的正相关关系(P<0.01);·OH含量与类胡萝卜素、类黄酮含量间存在极显著的负相关关系(P<0.01)。研究证实UV-B辐射增强通过产生大量的自由基对红松幼苗的生理代谢产生影响,而红松幼苗通过提高抗氧化酶(CAT,APX,SOD)的活性和蛋白质的含量来抵抗UV-B辐射引起的损伤,但其防御机制并不能有效地缓解这个伤害。 展开更多
关键词 红松 UV-B辐射 自由基 脂质过氧化 抗氧化酶
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