Establishment and Evaluation of Mouse Model of Ulcerative Colitis

The experiment was aimed to establish mouse model of ulcerative colitis(uc) by screening the optimum concentration of dextran sulfate sodium salt(DSS).Thirty BALB/c mice were randomly assigned to control group, 3.5% DSS group and 5% DSS group, ten mice each group.Mice drank water freely for 5 days, the body weights of everyday were recorded, stool was observed and stool occult blood was tested.After the experiment, the changes of TNF-α, MPO, MDA and GSH were tested, and the colon weight/length ratio was calculated.Compared with control group, the activity of MPO and content of MDA in the experiment groups were significantly increased(P<0.05), and content of GSH was significantly decreased(P<0.05).3.5% and 5% DSS both could successfully establish mouse model of ulcerative colitis.Mice in 5% DSS group had poor mental state, such as lethargy, malaise;Mice in 3.5% DSS group were appropriate, the mice mental was good, MPO, MDA and GSH were significantly different compared with control group(P<0.05), but there were no difference compared with 5% DSS group(P>0.05).So 3.5% DSS was more appropriate than 5% DSS to establish mouse model of ulcerative colitis.     

谷胱甘肽处理对采后鸭梨果实黑心病和抗氧化代谢的影响

谷胱甘肽(GSH)是一种重要的抗氧化剂。鸭梨果实经过负压渗透GSH后,并经缓慢降温最终贮存于0℃和80%￣90%的相对湿度(RH)条件下。结果表明,GSH能有效抑制鸭梨果实在低温贮藏6个月后黑心病的发生,处理果的黑心率及黑心指数分别比对照果降低了26.9%和37.1%。GSH处理的果实在贮藏过程中较对照具有较低的丙二醛含量,处理后果实中抗坏血酸、GSH含量以及超氧化物歧化酶、过氧化氢酶活性也明显高于对照果,抗坏血酸过氧化物酶较对照提前出现活性高峰,而谷胱甘肽还原酶的变化不明显。GSH处理对鸭梨果实黑心病的抑制作用可能与其增强了果实的抗氧化能力有关。     

不同接种时间对低能N+处理水稻幼苗抗氧化物的影响

以低能N+注入处理过的水稻种子为试验材料,对其在N6培养基上不同时间接种条件下幼苗抗氧化物酶类过氧化氢酶(CAT)、过氧化物酶(POD)的活性和还原型谷胱甘肽(GSH)的含量进行了测定.结果表明,经低能N+注入处理后的水稻种子在第1天接种时,其幼苗的CAT活性最高,第5天接种时,其活性最低,与对照组均呈显著差异;而其POD活性在第1天和第5天接种时的表现正好与CAT相反;同时,GSH含量在第3天接种时与对照无显著差异,而其余处理均显著低于对照.由此说明,不同的接种时间能够对低能N+辐照过的水稻幼苗期的生理特性产生明显的生物学效应.     

施用不同有机酸对烤烟生化指标的影响

本试验选取3种有机酸进行大田灌根,以清水为对照,研究了其对烤烟生化指标的影响,结果表明:腐殖酸处理能够明显促进烟株地上部和地下部鲜干重的增加,苹果酸处理对团棵期以前的烟株具有早生快的作用;腐殖酸能够提高烤烟叶片质体色素含量,促进烟株光合作用,生育后期能够促使烟株适时落黄成熟,且施用腐殖酸能够提高烟株的抗逆性和抗衰老能力,MDA含量、SOD活性、GSH含量均以施用腐殖酸处理的效果最好。     

仙鹤草水提物对小鼠主要脏器抗氧化指标的影响

试验通过检测仙鹤草水提物对小鼠几种主要脏器的抗氧化性指标的影响,找出适宜的药效剂量。将24只小鼠分成4组,分别为正常对照组、高剂量组、中剂量组、低剂量组。并用CPA造成免疫低下动物模型。喂养4周后,解剖小鼠,取脏器并称重,计算脏器指数。用分光光度法测定心、肺、肝、脾、肾和子宫中超氧化物歧化酶(SOD)活性、丙二醛(MDA)和谷胱甘肽(GSH)的含量。结果表明,仙鹤草通过降低小鼠一些脏器中的MDA含量提高SOD活力和GSH的相对含量来增强小鼠的抗氧化能力。经过综合判断低剂量组效果较好。     

谷胱甘肽对小麦幼苗铜毒害的缓解作用及其与氮、硫、磷积累的相关性

采用水培法,对外源谷胱甘肽(GSH)缓解小麦幼苗铜毒害及其与氮、硫、磷等元素积累的相关性进行了研究。结果表明,Cu处理(T0组)显著抑制小麦幼苗的生长发育,导致根长、茎叶长、生物量、叶绿素和类胡萝卜素含量以及氮元素积累量下降,诱导了植株蛋白质、内源GSH含量以及硫、磷元素积累量上升。随施用外源GSH浓度的升高,GSH处理(T1、T2、T3组)的小麦幼苗茎叶长、根长、生物量,叶绿素a、b和类胡萝卜素含量、蛋白质含量先上升后下降,内源GSH含量以及氮、硫、磷等营养元素积累量持续上升;其中,T2组小麦幼苗的各项指标与T0组差异均达到显著水平(P<0.05),与对照组(CK)无显著差异。外源GSH促进了植株对铜离子的吸收、转运和积累,而外源和内源GSH均与铜胁迫下小麦幼苗氮、硫、磷等营养元素的积累呈极显著正相关(P<0.01),其中以T2处理组缓解小麦幼苗铜毒害的作用最显著。     

安全剂R-28725保护玉米免受咪唑乙烟酸药害的机理研究

研究了安全剂R-28725对玉米的保护作用及对咪唑乙烟酸的解毒机理。当咪唑乙烟酸的使用量为20、40、60 g/hm2时,R-28725能够明显提高玉米株高、株鲜重和产量,直接增加植株体内谷胱甘肽(GSH)活性,增加咪唑乙烟酸与谷胱甘肽的轭合,从而达到解毒的目的。     

安全剂R-28725保护玉米免受氯嘧磺隆药害的机理研究

研究了安全剂R-28725对玉米的保护作用及对氯嘧磺隆的解毒机理。当氯嘧磺隆的使用量为5、10、15 g/hm2时,加入R-28725能够明显提高玉米株高、株鲜重和产量,直接增加玉米体内谷胱甘肽(GSH)含量,增加氯嘧磺隆与谷胱甘肽的轭合,从而达到解毒的目的。     

谷胱甘肽提高月季切花失水胁迫耐性与GR活性的关系

 本研究确定了切花月季‘Samantha’预处理采用的谷胱甘肽(GSH) 及其生物合成抑制剂丁胱亚磺酰胺〔L-buthione (S, R) sulfoximine, BSO〕适宜浓度, 探讨了GSH和BSO预处理对花朵水势、花瓣中MDA含量、GSH含量以及GR活性等的影响。结果表明: 与失水胁迫对照处理相比较, 2 mmol/L GSH预处理明显提高了月季切花瓶插期间花朵水势, 显著降低了花瓣中MDA含量, 有效提高了花瓣中GSH含量和GR活性。2 mmol/L BSO预处理获得了理想的反证结果。结果说明, GSH对切花月季‘Samantha’失水胁迫耐性的改善与花瓣中GR活性的提高相联系。     

Induction of disease resistance and ROS metabolism in navel oranges by chitosan

The objective of this work was to evaluate how disease resistance and reactive oxygen species (ROS) metabolism in harvested navel oranges (Citrus sinensis L. Osbeck) may be affected by chitosan. Fresh navel oranges were treated with 2% chitosan or 0.5% glacial acetic acid (control) solution for 1 min, and some were inoculated with Penicillium italicum and Penicillium digitatum. Then, the fruit were stored at 20 °C and 85–95% RH. Treatment with 2% chitosan significantly reduced the disease incidence and the lesion diameter compared with control fruit. This treatment effectively enhanced the activities of peroxidase (POD) and superoxide dismutase (SOD), and levels of glutathione (GSH) and hydrogen peroxide (H₂O₂), inhibited the activities of catalase (CAT) and the decreases of ascorbate (AsA) content during navel orange fruits storage. Ascorbate peroxidase (APX) activity in the navel orange fruit was induced slightly by the chitosan treatment during 14–21 days storage. However, glutathione reductase (GR) activity in the fruit was not enhanced by the chitosan treatment. These results indicated that chitosan treatment could induce the navel orange fruit disease resistance by regulating the H₂O₂ levels, antioxidant enzyme and ascorbate–glutathione cycle.