砷对大豆种子萌发的伤害

大豆种子经正常吸胀萌动后，如果受到砷的毒害，则其下胚轴过氧化氢酶和超氧物歧化酶（ＳＯＤ）活性下降，过氧化物酶活性升高，脂质过氧化产物丙二醛（ＭＤＡ）含量升高；下胚轴和根的生长明显受到抑制，巨受抑制程度随砷浓度的增加和处理时间的延长而加剧。因此，推测砷对大豆种子萌发过程的伤害与活性氧代谢的失调有关。     

低氧和高氧对大菱鲆幼鱼红细胞核异常及氧化抗氧化平衡的影响

研究了极低氧(0.2、1.0、2.0 mg/L)、低氧(3.0、5.0 mg/L)和高氧(11.0、14.0 mg/L)处理28 d期间,大菱鲆幼鱼外周血红细胞核异常以及血清超氧化物岐化酶(SOD)、过氧化氢酶(CAT)活力和肝脏丙二醛(MDA)含量等氧化抗氧化平衡中参数的变化。结果显示,极低氧条件下,0.2、1.0和2.0 mg/L组的实验鱼分别在处理2 h、1 d和2 d内全部死亡,其余各组则没有出现死亡现象。溶解氧(DO)对大菱鲆核异常包括微核及总核异常率的影响表现出明显的时间和剂量累积效应,到28 d时才在5.0、14.0 mg/L组和对照组中(正常充气,约7.0 mg/L)观察到微核现象。恢复正常充氧14 d后,高氧组和对照组中仍有微核现象出现。2 h时极低氧组SOD活力较高。其他各处理时间时,SOD活力在各组之间差异显著。各组CAT活力在2 h时未发生明显变化,在7、28和42 d时差异显著(〖WTBX〗P〖WTBZ〗<0.05)。极低氧组大菱鲆肝脏MDA含量较低,低氧组和高氧组MDA含量均随着处理时间的延长逐渐降低。恢复后低氧组MDA含量显著升高(〖WTBX〗P〖WTBZ〗<0.05)。研究还发现,对照组大菱鲆也会受到过氧化的胁迫作用,而5.0 mg/L组的总核异常率和所测氧化还原指标在整个实验期间均未发生明显变化。     

柑桔果实浮皮发生机理及控制途径研究Ⅱ．特早熟温州蜜果实浮皮与衰老的关系

为探明柑桔果实浮皮与衰老的关系，以特早熟温州蜜柑品种胁山为试材，采前对其幼果和枝叶喷施赤霉素、亚精胺、醋酸钙，测定果皮及果肉的多聚半乳糖醛酸酶（PG）、超氧化物歧化酶（SOD）和丙二醛（MDA）等生理生化指标。结果表明：胁山品种随着果实浮皮的出现，PG活性提高，果皮的细胞膜脂质过氧化作用产物MDA逐渐积累，而果皮和肉的SOID活性则急剧下降。胁山果实浮皮的根本原因是膜脂过氧化作用引 果皮早衰。采前喷施赤霉素、亚精胺、醋酸钙对MDA含量，PG，SOD活性均有一定调节作用，其中以赤霉素效果最佳。     

GCA对小鼠腹腔巨噬细胞抗氧化作用的影响

以小鼠腹腔巨噬细胞为研究对象,探讨牛羊胆汁提取物甘氨胆酸（glycocholic acid,GCA）的抗氧化作用。将GCA分为1×10^-3、1×10^-4、1×10^-5、1×10^-6、1×10^-7 μg/mL 5个质量浓度,与小鼠腹腔巨噬细胞共同孵育24 h后,按照试剂盒说明书提供的方法测定小鼠腹腔巨噬细胞中抗氧化酶谷胱甘肽过氧化物酶（GSH-Px）、超氧化物歧化酶（SOD）活性以及丙二醛（MDA）含量。结果表明,GCA能降低小鼠腹腔巨噬细胞中MDA的含量,同时提高小鼠腹腔巨噬细胞GSH-Px、SOD的活性,从而调节小鼠腹腔巨噬细胞的抗氧化应激水平。该试验结果提示甘氨胆酸具有改善抗氧化应激反应的能力。     

Effect of arbuscular mycorrhizal fungi on growth,mineral nutrition,antioxidant enzymes activity and fruit yield of tomato grown under salinity stress

The purpose of this study was to investigate the mechanisms underlying alleviation of salt stress by arbuscular mycorrhizal fungi Glomus mosseae. Tomato (Lycopersicon esculentum L. cv. Zhongzha105) plants were cultivated in soil with 0, 50 and 100 mM NaCl. Mycorrhization alleviated salt induced reduction of root colonization, growth, leaf area, chlorophyll content, fruit fresh weight and fruit yield. The concentrations of P and K were higher in AM compared with nonAM plants grown under nonsaline and saline conditions. Na concentration was lower in AM than nonAM plants grown under nonsaline and saline conditions. AMF colonization was accompanied by an enhancement of activity of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD) and ascorbate peroxidase (APX) in leaves of both salt-affected and control plants. In addition, inoculation with AMF caused reduction in MDA content in comparison to salinized plants, indicating lower oxidative damage in the colonized plants.     

Coexpression with Auxiliary β Subunits Modulates the Action of Tefluthrin on Rat Na(v)1.6 and Na(v)1.3 Sodium Channels

The erythrocyte, due to its role as O₂ and CO₂ transporter, is under the constant exposure to reactive oxygen species and oxidative stress. The objective of this study was to investigate the ability of 2,4-D to induce oxidative stress in blood of male wistar rats. Rats were randomly divided into four groups: a control group and three treated groups receiving by gavage 15, 75 and 150 mg, respectively, of 2,4-D/kg/BW/day for 28 days. Results showed that 2,4-D caused significant negative changes in the investigated biochemical parameters. In fact, 2,4-D exposition strongly increases LDH, by contrast, there is a statistically significant decrease in Hgb levels. The malondialdehyde level was significantly increased in 2,4-D treated groups. Fatty acid composition of the erythrocytes was also significantly changed with 2,4-D exposure, in favor of the peroxidation of polyunsaturated fatty acids. Furthermore, antioxidant enzyme (SOD, CAT, GPx, and GR) activities in erythrocytes were significantly decreased. Thus, our results indicated the potential effects of 2,4-D to cause oxidative stress in rat erythrocytes. Therefore, at higher doses, 2,4-D may play an important role in the development of vascular disease via lipid peroxidation and oxidative stress.     

Herbicidal action of clove oil on cucumber seedlings

The herbicidal action of clove oil on cucumber seedlings was characterized under light and dark conditions. Paraquat showed herbicidal activity only under the light condition, whereas the clove oil displayed herbicidal activity in both the light and the dark condition. Specifically, wilting and water content reduction progressed rapidly under both the light and the dark condition 1 h after the clove oil treatment, whereas the paraquat damage occurred only under the light condition 5 h after treatment. The malondialdehyde concentration increased more with the clove oil treatment than with the paraquat treatment under the light and dark conditions. The superoxide dismutase (SOD) activity was stimulated, but the catalase activity decreased in the clove oil treatment. In contrast, both the SOD and catalase activity decreased in the paraquat treatment. These results suggest that clove oil exerts herbicidal effects through a mechanism that is different from that of paraquat.     

Oxidative Damage to Spodoptera litura Cell Induced by α-Terthienyl

In this study, the oxidative damage of α-terthienyl (α-T) to the Spodoptera litura (SL) cell and its mechanism were investigated. MTT was used to compare the toxicity of α-T and rotenone to the SL cell. The output of malondialdehyde and relative content of glutathione were determined with 2-thiobarbituric acid (TBA) and 5, 5'-dithio-bis (2-nitrobenzoic acid) (DTNB), respectively. Transmission electron microscope (TEM) was employed to observe the influence of α-T on the membrane and organelle of the SL cell. The result showed that the IC50 value of α-T to the SL cell was 0.21 μg mL-1, whereas the corresponding dose of rotenone was 12.25 μg mL-1. The output of MDA had the same changing tendency with the concentration of α-T, whereas the content of GSH had the negative correlation with it. According to TEM, the cell membrane and karyotheca swelled and couldn't retain integrity, the intracellular substances leaked out, unidentified granules appeared in the SL cell. The mitochondria expanded, and the membrane and subcellular organelle were damaged severely.In this study, it was found that after oxidative damage induced by α-T, the output of MDA increased notably, whereas the relative content of GSH decreased. This indicated that the antioxidant ability of cell weakened. The result of TEM implied that the SL cell suffered from oxidative damage under the appointed dose.     

不同杏品种抗寒性及生理指标

以"晋梅杏""凯特""鸡蛋杏""金太阳"一年生休眠枝条和带花枝条为试材,通过不同低温处理,测定膜透性、保护酶活性和渗透调节物质,比较生理指标在低温下的变化以及与抗寒性的关系,分析各指标间的相关性,以期为筛选抗寒新品种提供参考依据。结果表明:随温度降低,枝条相对电导率、枝条丙二醛(MDA)含量、枝条脯氨酸含量、杏花MDA含量、杏花脯氨酸含量呈上升的趋势;枝条超氧化物歧化酶(SOD)活性、花朵SOD活性整体呈先升后降的趋势。"凯特"枝条中MDA含量与其它3个品种差异显著;"金太阳"枝条中脯氨酸含量与其它3个品种差异显著。花朵中MDA含量与4个杏品种的抗寒性呈负相关;除"鸡蛋杏"以外,枝条中脯氨酸含量与抗寒性呈正相关。相对电导率和枝条中SOD活性、枝条中脯氨酸含量、花朵中MDA含量呈极显著正相关,与花朵中脯氨酸含量呈显著负相关。花朵中MDA含量与花朵中SOD活性、花朵中脯氨酸含量呈极显著负相关;花朵中SOD活性与花朵中脯氨酸含量呈极显著正相关。综上所述,4种杏品种抗寒性强弱顺序为"金太阳">"晋梅杏">"鸡蛋杏">"凯特"。     

Effects of dietary ascorbic acid/iron ratio on some production traits, lipid peroxide state and amount/activity of the glutathione redox system in African catfish Clarias gariepinus (Burchell) fingerlings

African catfish Clarias gariepinus (Burchell) fingerlings (3.16–3.92 g initial body weight) were investigated for 30 days in four different groups using different amounts of l ‐ascorbic acid (AA) and iron (supplied as FeC₆H₅O₇) in their feedings. Diet 1 (control): no addition of AA or iron; diet 2 (H‐AA/FE): high (600 mg kg^?1) AA and low (218 mg kg^?1) iron; diet 3 (H‐HE/AA): high (364 mg kg^?1) iron and low (200 mg kg^?1) AA; and an unfed group, which was investigated only for 15 days due to high mortality. The live weight gain, feed intake, specific growth rate (SGR; % body weight day^?1) and feed conversion rate (FCR) were measured or calculated. At the end of the experimental period, the whole body content of AA, iron, reduced glutathione (GSH), glutathione disulphide (GSSG) and malondialdehyde (MDA), as well as the glutathione peroxidase (GSHPx) activity, were measured. The production traits did not differ significantly as a result of the different AA and iron contents of the feed. AA content increased significantly in all the groups as compared with the initial value, except in the unfed group. The difference between the treated groups as compared with the control, with regard to the two AA/iron treated groups, was also significant. The iron content in the fish body increased significantly compared with the initial value, except in the unfed group. The difference compared with the control was significant only in the H‐FE/AA group. The difference between the groups that consumed low and high iron content diets was also significant. The GSH and GSSG content, as well as the GSH/GSSG ratio and GSHPx activity of the fish body, did not differ significantly as compared with the initial value or with the control. The lipid peroxide status, as measured by the MDA content, did not differ significantly either as an effect of the AA and iron supplementation, but decreased as an effect of ageing and starvation. It may be concluded that, under the present experimental conditions, the C. gariepinus fingerling tissue stores of AA and/or iron increased as a result of feed supplementation, but without altering the actual lipid peroxide status and the amount/activity of the glutathione redox system.