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1.
研究了烟草BY-2悬浮细胞在脱落酸(ABA)诱导下产生过氧化氢(H2O2)的机制,发现ABA能够显著诱导H2O2快速产生,且H2O2主要是由超氧化物歧化酶催化超氧阴离子产生的.ABA处理可导致烟草悬浮细胞质膜NADPH氧化酶活性以时间依赖的方式快速增加,其增加的幅度和时间与ABA诱导H2O2积累一致,而且,这些增加的效应能够被NADPH氧化酶抑制剂碘二苯和咪唑显著抑制,说明质膜NADPH氧化酶参与烟草悬浮细胞H2O2快速积累过程.另外,用RT-PCR和蛋白印迹技术分析了烟草质膜NADPH氧化酶基因NtrbohD的表达水平,发现该基因在mRNA和蛋白水平的表达受ABA上调,表明NtrbohD参与烟草悬浮细胞ABA诱导H2O2快速产生过程.结果说明,ABA能够诱导悬浮细胞通过NADPH氧化酶快速产生活性氧,提示NAD-PH氧化酶和H2O2可能是植物细胞中ABA信号转导途径的重要成分。  相似文献   

2.
各种胁迫下过氧化氢(H2O2)产生量增加,不仅具有损伤生物大分子从而伤害细胞的效应,而且是一种重要的信号分子。本文主要就H2O2在植物遭受不同胁迫下的调控作用做一综述。  相似文献   

3.
目的:在H2O2胁迫下,研究番茄红素增强成骨细胞抗自由基损伤的作用.方法:用H2O2作用MC3T3-E1成骨细胞,建立自由基损伤细胞模型.培养的成骨细胞分为对照组、模型组、番茄红素低剂量组(1×10-8mol/L)、番茄红素中剂量组(1×10-7mol/L)和番茄红素高剂量组(1×10-6mol/L).测定不同处理组细胞活力、超氧化物歧化酶(superoxide dismutase,SOD)活性、活性自由氧(reactive oxygen species,ROS)含量、脂质过氧化物(1ipid oxygen,LPO)含量,同时利用荧光偏振法测定细胞膜流动性.结果:模型组细胞活力、SOD活性、细胞膜流动性均比不同番茄红素组有显著降低(P<0.01),而ROS含量、LPO含量均比不同番茄红素组有显著升高(P<0.01).结论:H2O2摄入会导致大鼠成骨细胞的氧化损伤,而番茄红素可以预防或降低此类损伤对细胞的影响.  相似文献   

4.
利用H2O2提高GS115rhZP3培养中的溶氧和目的蛋白产量   总被引:1,自引:0,他引:1  
目的:提高毕赤酵母摇瓶培养中的溶氧,从而提高目的蛋白的表达量.方法:在rhZP3工程菌培养过程分别加入不同浓度的H2O2,甲醇诱导培养后,取培养液上清进行SDS-PAGE电泳和Western blot,并与不加H2O2的对照组比较,分析H2O2对重组人卵透明带ZP3蛋白(rhZP3)在毕赤酵母中表达量的影响.结果:H2O2可提高培养基的溶氧量.当H2O2浓度为5mmol/L时,目的蛋白的表达量最高。结论:在rhZp3毕赤酵母工程菌摇瓶培养中,加入H2O2可提高rhZP3的表达量.  相似文献   

5.
为了研究α-硫辛酸(lipoic acid, LA)对心血管氧化损伤的保护作用,本研究以离体培养的小牛主动脉血管内皮细胞和平滑肌细胞为实验材料,探讨了LA 对这两种细胞氧化损伤的影响.结果表明,在H2O2胁迫下,LA可以剂量依赖性地提高细胞内的超氧化物歧化酶(SOD)活性,抑制细胞内过氧化产物丙二醛(MDA)的产生,提示LA对小牛主动脉血管内皮细胞和平滑肌细胞氧化损伤有保护作用.本研究为LA的保健和药用价值开发,特别是对LA在保护心血管免受氧化损伤的功效的研发,提供了自由基生物学实验依据.  相似文献   

6.
用H2O2(w=30%)对含烯烃的模拟油品进行氧化,探讨了各种催化剂对氧化反应的影响。结果表明,酸碱催化剂都可促进H2O2氧化反应的进行,对降低油品中烯烃效果,有机酸条件明显好于碱性和中性条件,甲酸的催化效果优于乙酸。在H2O2甲酸氧化降烯烃的过程中,当3种样品的体积比即V(模拟油品):V(H2O2):V(甲酸)=4:1:1,反应温度45℃,反应时间1h时,模拟体系中烯烃降低率为35.8%,流化催化裂化汽油中烯烃降低率达22.1%。  相似文献   

7.
为给抗氧化损伤药物的开发利用和抗氧化损伤机制的研究提供理论依据和实验基础,本方法构建了过氧化氢(H2O2)体外诱导小鼠胚胎成纤维细胞(NIH-3T3)经典的氧化应激损伤模型.应用贴壁细胞培养法培养NIH-3T3细胞,采用不同浓度的H2O2处理NIH-3T3细胞不同时间模拟氧化损伤模型,通过CCK-8法观察H2O2引起N...  相似文献   

8.
树干毕赤酵母固定化细胞的酒精发酵   总被引:1,自引:0,他引:1  
利用海藻酸铝酸胶包埋,将低浓度的树干毕赤酵母(Pichia stipitis)细胞固定,其凝胶粒直径约2-3mm,经增殖培养,使凝胶珠表面的细胞密集,极大地减少了传递阻力,有利于该酵母细胞的“半好气”酒精发酵,结果表明,固定化细胞戊糖,己糖同步酒精发酵糖液初始PH5.0-5.5较适宜;混合糖60g/L(50%葡萄糖、50%木糖)的固定化细胞酒精发酵,发酵前12h主要利用葡萄糖,12h以后木糖利用占主导地位,以低PH(2.8,2.4,2.0)无菌水处理酵母细胞海藻酸铝凝胶珠,2-3h后又恢复正常PH(5.0)。用PH2.8无菌水处理固定化细胞2-3h,细菌基本上被杀死,而酵母细胞功能不受影响,当PH2.4时,对酵母细胞影响较大,而PH2.0时,酵母细胞严重受损,大部分死亡。  相似文献   

9.
目的 探讨大气细颗粒物PM2.5暴露对Wistar大鼠急性脾损伤的影响。方法:PM2.5冬夏混合膜由实验室保留。将大鼠随机分为实验组和对照组(n = 8),实验组4 h /天750 g·mL-3 PM2.5口鼻暴露处理,对照组生理盐水,5 d / 周,共2周,染尘结束24 h后处死,称重收集脾脏上清和细胞,HE染色观察脾组织形态学变化。检测脾上清H2O2含量水平。cell viabitity assay和qRT-PCR仪器检测脾细胞的Bax、BcL-2水平的表达情况。结果:HE染色结果发现,PM2.5可增加脾生发中心的淋巴细胞。PM2.5染尘后实验组大鼠体重明显低于对照组,差异均有统计学意义(P < 0.05)。PM2.5染尘可增加脾上清H2O2含量水平。脾细胞活力和凋亡结果表明,PM2.5暴露可抑制脾细胞的增值能力以及上调Bax和Bcl-2基因表达。结论:PM2.5染尘可引起脾脏氧化损伤,促使氧化应激水平上升,发生炎症反应,增加脾细胞的增值能力,最终对脾产生一定的损害作用。  相似文献   

10.
细胞凋亡是细胞自主的有序死亡,caspase家族在细胞凋亡中起着重要的作用,ICE(Interlukin-1β—converting enzyme,白细胞介素-1β转换酶)是Caspase家族的一员,又称Caspase-1。为了了解家蚕ice-2和ice-5基因(GenBank登录号为:DQ360829和DQ360830)在凋亡信号通路中的作用,采用紫外线等刺激家蚕幼虫和家蚕细胞,利用荧光定量PCR的方法测定不同因素刺激下的ice-2和ice-5的表达量的变化。结果显示ice-2和ice-5都与家蚕的细胞信号转导有关,ice-5可能比ice-2起更重要的作用。  相似文献   

11.
The mechanisms for the production of hydrogen peroxide (H2O2) induced by abscisic acid (ABA) were investigated in suspension culture cells of tobacco BY-2 cells. The results showed that the immediate generation of H2O2, which was mainly derived from super-oxide dismutase-catalyzed dismutation of superoxide radical, was significantly induced by ABA. Furthermore, treatment of the cultured tobacco cells with ABA resulted in a time-dependent quick increase in plasma membrane (PM) NADPH oxidase activity, which coin- cided on time and magnitude with the elevation in ABA-induced accumulation of H2O2. Moreover, these enhanced effects were pro- nouncedly inhibited by two NADPH oxidase inhibitors, diphenylene iodonium and imidazole, suggesting that PM NADPH oxidase is involved in the rapid accumulation of H2O2 in cultured tobacco cells. In addition, analysis of the expression level of NtrbohD, a PM NADPH oxidase gene in tobacco, by RT-PCR and protein gel blot revealed that the gene at both mRNA and protein levels was upregulated by ABA, indicating that NtrbohD participates in the ABA-stimulated rapid production of H2O2 in tobacco culture cells. Taken together, these findings suggest that ABA induces the rapid accumulation of reactive oxygen species via NADPH oxidase in sus-pension culture cells of tobacco, and that NADPH oxidase and H2O2 appear to be important components in ABA signal transduction pathway in plants.  相似文献   

12.
为了解决高溴黄河水臭氧化过程中溴酸盐(BrO-3)生成问题,在连续实验装置中,采用H2O2/O3高级氧化技术(AOPs)技术,研究臭氧(O3)、过氧化氢(H2O2)质量浓度以及水力停留时间(HRT)对黄河水BrO3-生成控制的影响。研究结果表明:H2O2的投加能够有效促进O3消耗;当O3质量浓度为2.9~4.3mg/L时,单独臭氧化过程中,BrO-3生成量为13~50μg/L,均超标,投加H2O2能够有效抑制BrO3-的产生,其抑制效果与H2O2/O3的摩尔比有关,当H2O2/O3摩尔比为1.5时,控制效果最佳,当O3质量浓度低于3.72mg/L时,在此比例时可将BrO-3浓度控制在10μg/L以下,达到现行的饮用水标准;BrO3-生成量与HRT成正比;当O3质量浓度较高时,可通过适当减少HRT控制出水BrO-3浓度。H2O2/O3高级氧化工艺对有机物的去除具有强化作用,出水UV254去除率可达50%以上。  相似文献   

13.
以普通无机盐为原料采用沉淀法制备了Cu3V2O7(OH)2·2H2O纳米片.采用X射线衍射(XRD)和场发射扫描电子显微镜(FE-SEM)对样品的组成和表面形貌进行了表征.紫外-可见光吸收测试显示Cu3V2O7(OH)2·2H2O纳米片具有较宽的紫外-可见光吸收范围,带隙宽度为2.22 eV.  相似文献   

14.
A new resistless etching method has been developed for Silicon wafers. This new method uses an aqueous solution consisting of hydrogen peroxide (H2O2) and hydrogen fluoride (HF) as the activating etchants. A 193 nm ArF excimer laser and a 266 nm fourth harmonic generation Nd:YAG laser were used as the photon sources. Results showed that pattern etching has been achieved without any photoresist film. In the case of the 193 nm laser, the optimal etching appeared at a 1.3 H2O2/HF ratio, where an etch depth of 210 nm was achieved with a fluence of 29 mJ/cm2 and shot number of 10000. At the same conditions, the etch depth with H2O2 and HF solution was three times of that by using H2O and HF mixture. In the case of the 266 nm Nd:YAG laser, the optimal etching appeared at twice ratio of H2O2/HF, where the etch depth of 420 nm was achieved with a fluence of 12 mJ/cm2 and shot number of 30000. Results showed that the etch effect of the 266 nm Nd: YAG laser was more desirable than that of the 193 nm ArF excimer laser.``Keyords: UV laser, resistless photochemical etching, hydrogen peroxide (H2O2).  相似文献   

15.
Although protein tyrosine phosphatases (PTPases) play an important role in signal transduction in animal cells, little is known about the function of PTPases in higher plants. Hydrogen peroxide (H2O2) and mitogen-activated protein kinases (MAPKs) are the critical components of ABA signaling pathway in guard cells. PTPase is an important regulator of MAPK, which is believed to mediate ABA-induced H2O2 generation in guard cells of Vicia faba L. Here, we investigate the possible role of PTPases in stomatal movement process. Phenylarsine oxide (PAO), a specific inhibitor of PTPases, could prevent ABA or H2O2-induced stomatal closure of Vicia faba L; furthermore, it could promote opening of the stomata closed by ABA or H2O2. The activity of PTPases can be effectively inhibited by PAO and H2O2. DTT had no effect on the PAO-induced inhibition of PTPases activity, but it could relieve the inhibition of H2O2 on PTPases activity. PAO could also inhibit the ABA-induced H2O2 generation in guard cells of V‘wia faba L. These results suggested that PTPases is a critical signaling component in ABA-induced stomatal closure, and serve as targets for H2O2 lying on the signaling pathways downstream of ABA induced H2O2 generation.  相似文献   

16.
采用共沉淀法合成新型催化剂S2O28-/CaO.Fe2O3粉体。用红外光谱对其结构进行表征,并考察了助催化剂H2O2的用量、催化剂的投加量以及不同光源对罗丹明B溶液催化降解的影响。实验结果表明,所研制的S2O28-/CaO.Fe2O3粉体为固体超强酸,粒径处于纳米数量级,且其在紫外光区556 nm处有个紫外特征峰。在浸渍液(NH4)2S2O8浓度为0.5 mol/L、S2O28-/CaO.Fe2O3投加量为0.03g/25 mL、H2O2用量为1.00 mL/25 mL下,对浓度为0.6 g/L的罗丹明B溶液在自然光下静置1 h,其降解率可达99.2%。同时还初步探讨了催化降解过程中物理现象与化学性质分析、酸中心的形成机理及催化剂失活的可能原因。  相似文献   

17.
以CeCl3·7H2 O为铈源、NH3· H2 O为矿化剂、HCl为酸性调节剂,利用水热法成功制备了二氧化铈纳米颗粒.采用X射线衍射仪(XRD)、扫描电子显微镜(SEM )、紫外‐可见分光光度计(UV‐Vis)、荧光分光光度计(PL )、拉曼光谱(Raman)和振动样品磁强计(VSM )等分析测试手段,对CeO2纳米颗粒的晶相、形貌、光学和磁学性质进行了表征.XRD测试结果表明样品的晶格参数略高于块状CeO2的,并随着pH值的增大而减小.所有样品的形貌均为球形.从紫外‐可见吸收光谱中,估计出的样品直接带隙值小于块状CeO2的,且此值随pH值的增加而增加.pH值为2时合成样品具有室温铁磁性,此性质的出现可能与Ce3+和氧空位的存在有关.  相似文献   

18.
次氯酸钠/过氧化氢法处理含铜绿微囊藻原水   总被引:3,自引:0,他引:3  
以铜绿微囊藻实验室单培养液及其10倍稀释液为原水,pH分别为7.3、7.6,用NaOCl和H2O2作氧化剂,以663nm吸光度变化百分率为指标,分别研究了单独氧化及先应用NaOCl后续H2O2氧化处理、再对已处理过的水样分别投加PAC混凝去除铜绿微囊藻的效果.结果表明:在水中NaOCl、H2O2浓度分别为2.0、1.5mg/L条件下,NaOCl、H2O2、联合氧化处理原水和稀释水的去除率分别为82.2%、50%,83.3%、57.1%,92.2%、78.5%;再分别投加PAC,浓度为40mg/L,混凝沉淀后,单独投加氧化剂的水样的去除率均不超过90%,联合氧化后的水样的去除率达到100%.NaOCl或H2O2刺激藻细胞分泌保护性粘性物质,这些粘性物质包裹藻细胞形成沉降性能良好的聚集体,但对PAC混凝有不利影响,联合氧化改善了这些物质的特性而促进了混凝效果.  相似文献   

19.
The plant hormone abscisic acid (ABA) is involved in regulating adverse physiological processes, including stomatal closure, seed development and germination, and mediating many environmental stress responses, such as drought, salinity and extreme temperatures[1,2]. In re-sponse to various stress stimuli, ABA synthesis is in-creased in plant cells, which triggers a series of physio-logical responses to adapt the stress conditions[1—3]. For example, under water deficit, ABA acts directly on…  相似文献   

20.
二-(2-乙基己基)二硫代磷酸萃取钯机理的研究   总被引:2,自引:0,他引:2  
报道了二-(2-乙基己基)二硫代磷酸(D2EHDTPA)从高氯酸体系中萃取钯的机理,结果表明,钯的萃取率随PH的增大而增大,与高氯酸根离子浓度的无关,采用斜率法测算萃合物组成的PdL2。  相似文献   

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