Methyl parathion induced nephrotoxicity in male rats and protective role of vitamins C and E

Methyl parathion is an organophosphate insecticide that has been used in agriculture and domestic for several years. Vitamin C (200 mg/kg bw per day) + vitamin E (200 mg/kg bw per day), methyl parathion (0.28 mg/kg bw per day) and vitamin C (200 mg/kg bw per day) + vitamin E (200 mg/kg bw per day) + methyl parathion (0.28 mg/kg bw per day) combination were given to rats orally via gavage for 7 weeks. Body and kidney weights, malondialdehyde (MDA) levels and histopathological changes were investigated at the end of 4th and 7th weeks comparatively with control group. When methyl parathion-treated group and vitamins C and E + methyl parathion-treated group were compared to control group body and kidney weights decreased significantly at the end of 4th and 7th weeks. MDA levels increased in kidney tissues of the methyl parathion- and vitamins C and E + methyl parathion-treated groups compared to control group. MDA levels decreased significantly in vitamins C and E + methyl parathion treated group compared with methyl parathion treated group at the end of 4th and 7th weeks. In our light microscopic investigations, after 4 weeks of methyl parathion exposure, glomerular atrophy and vascular dilatation, and after 7 weeks, necrosis and edema were observed in the kidney tissues. After 4 weeks of vitamins C and E + methyl parathion exposure, mononuclear cell infiltrations, and after 7 weeks, calcification were detected in the kidney tissues.     

Soil solarization in various agricultural production systems

Soil solarization is a natural, hydrothermal process of disinfesting soil of plant pests that is accomplished through passive solar heating. Solarization occurs through a combination of physical, chemical, and biological mechanisms, and is compatible with many other disinfestation methods to provide integrated pest management. Commercially, it is used on a relatively small scale worldwide as a substitute for synthetic chemical toxicants, but its use is increasing as methyl bromide, the major chemical fumigant, is phased out due to its ozone-depleting properties. Solarization currently is an important and widespread practice for home gardeners. In production agriculture, the principal use of solarization (on a treated area basis), is probably in conjunction with greenhouse grown crops. Another application for which solarization has come into common use is for disinfestation of seedbeds, containerized planting media, and cold-frames. Around the world, solarization for disinfesting soil in open fields is being implemented at a relatively slow but increasing rate. It has been mainly used for commercial production in areas where air temperatures are very high during the summer and much of the cropland is rotated out of production due to excessive heat. As global concerns regarding environmental quality grow along with the human population in the 21st century, concepts such as solarization and other uses of solar energy in agriculture will likely become increasingly important.     

茉莉素及其功能

茉莉素是一类新型植物激素 .报道了国内外学者对茉莉素及其功能的研究进展 ,包括茉莉素的分布、化学结构、生物合成及其功能等     

Induction of flavonoid production by UV-B radiation in Passiflora quadrangularis callus cultures

Callus cultures from several species of Passiflora were initiated in vitro, and their capacity to produce four glycosyl flavonoids (orientin, isoorientin, vitexin, isovitexin) was analysed. The aim of the present work was to examine the possible role of UV-B irradiation and elicitation with methyl jasmonate (MJ) on the production of these compounds in callus cultures. All the species tested (P. incarnata, P. quadrangularis, P. edulis) formed friable callus from leaf explants after 4 weeks on medium supplemented with kinetin and 2,4-dichlorophenoxyacetic acid. Among them, P. quadrangularis turned out to have a faster growth rate and a more friable texture, and was therefore chosen for experiments with elicitors. In callus cultures only small amounts of isoorientin were found, while the concentration of the other flavonoids was below the detection limit. UV-B irradiation of calluses was able to increase the production of all four glycosyl flavonoids. After a 7-day exposure of cultures to UV-B light, the production of isoorientin reached concentrations similar to those found in fresh leaves from glasshouse-grown plants. Elicitation with methyl jasmonate also enhanced orientin, vitexin and isovitexin concentrations, even though the stimulation was about 6-fold weaker for orientin and vitexin and about 40-fold for isovitexin, than that exerted by UV-B treatment. Callus cultures treated with the UV-B dose which most enhanced flavonoid production showed a higher antioxidant activity compared to untreated calluses, with an increase ranging from 28% to 76%. Results show that the secondary metabolite biosynthetic capacity of Passiflora tissue cultures can be enhanced by appropriate forms of elicitation.     

茉莉酸甲酯对红地球葡萄采后贮藏品质和病害的影响

[目的]研究茉莉酸甲酯(MeJA)浸泡处理对葡萄采后病害的控制及贮藏品质的影响.[方法]以新疆红地球葡萄为试材,采用50、100和200μmol/L茉莉酸甲酯(methyl jasmonate,MeJA)室温(25℃)浸泡处理葡萄,(0±1)℃贮藏,每隔10 d测定果实硬度、可溶性固形物含量、可滴定酸含量及腐烂率的变化...     

微波萃取液相色谱-电感耦合等离子体质谱联用测定水产品中甲基汞、乙基汞和无机汞

[目的]研究水产品中甲基汞、乙基汞和无机汞的检测方法。[方法]采用Hypersil gold 150×4.6 mm色谱柱进行HPLC分离条件优化,用含Li、Co、In、U各1μg/L的调谐液进行ICP-MS参数优化,对样品进行微波萃取。[结果]采用盐酸微波萃取样品,C18柱(150×4.6 mm)分离,流动相为5%甲醇-0.06 mol/L乙酸铵-1 g/L半胱氨酸。甲基汞、乙基汞的线性范围均为0.5~100.0μg/L,检出限分别为0.2、0.3μg/L;无机汞线性范围均为0.5~20.0μg/L,检出限为0.2μg/L。不同浓度下甲基汞、乙基汞、无机汞的加标回收率分别为89%~98%、82%~89%、86%~96%。鱼肉标准物质(GBW10029)中汞形态的测定均值在标准值范围内。[结论]该方法前处理简便、精密度高、准确性好,适用于水产品中汞化合物的形态分析。     

覆盖不透膜、少用甲基溴的土壤消毒效果及对温室番茄生长的影响

2001~2003年在山东省青州市温室中进行了2次减量甲基溴、覆盖不透膜(VIF膜)土壤消毒试验。在田间相同条件下,用甲基溴对种植番茄的大棚土壤进行消毒处理,分别覆盖不透膜和普通聚乙烯膜(PE膜)。试验结果表明,甲基溴低量处理37.5 g/m2覆盖VIF膜与常规用量50 g/m2覆盖PE膜比较,在对根结线虫病控制、生长特征及产量上均无显著差异。使用VIF膜可显著减少甲基溴渗漏,减少用量25%以上,从而减少对臭氧层的破坏。     

固体碱法制备生物柴油组分生成动力学

[目的]探讨固体碱法制备生物柴油中组分油酸甲酯的生成动力学。[方法]以精制菜籽油和甲醇为原料,固体碱CaO/MgO作催化剂,菜籽油与甲醇在固体碱催化下进行酯交换反应制备生物柴油,用气相色谱法跟踪分析生物柴油(脂肪酸甲酯)的含量,考察生物柴油中组分油酸甲酯的生成动力学。[结果]动力学研究表明,固体碱CaO/MgO催化菜籽油和甲醇的酯交换反应速率方程为rA=dCp/dt=k1CA2。反应速率动力学方程分3个阶段,反应开始为引发阶段,逐步转变为增长阶段的2级反应,最终反应达到平衡阶段。油酸甲酯增长阶段反应活化能为58.48 kJ/mol,频率因子为9.18×105 L/(mol.min)。[结论]该研究为固体碱催化菜籽油与甲醇酯交换反应的动力学提供了理论基础。     

茉莉酸甲酯抑制小麦根生长及体内抗氧化酶活性变化

试验表明,采用聚丙烯酰胺电泳技术研究不同浓度的Me-JA处理小麦后其体内抗氧化物酶活性的变化.与对照相比,高浓度(10-5～10-3mol/L)的茉莉酸甲酯(Me-JA)对小麦根的生长均有明显的抑制作用,而低浓度(10-8～10-7 mol/L)的Me-JA却有轻微的促进作用.随外施的茉莉酸甲酯浓度梯度的升高,过氧化物酶的表达量依次增强,以10-4 mol/L浓度的表达量最为强烈.经过茉莉酸甲酯的处理,小麦根中总可溶性的过氧化物酶的活性能提高,茉莉酸甲酯对过氧化物酶(POD)活性提高明显 ,细胞中的过氧化物酶主要是防止细胞壁的延伸,从而可能达到阻碍小麦生长的作用.     

茉莉酸甲酯对马尾松松针萜烯类挥发物及马尾松毛虫生长发育的影响

用不同浓度茉莉酸甲酯喷洒马尾松,对其针叶挥发物进行测定,并记录用不同浓度茉莉酸甲酯喷过的松针饲喂马尾松毛虫的各项生理指标。结果表明:针叶挥发物以萜烯为主,其中苧烯、柠檬烯、β-水芹烯、石竹烯、p-薄荷-1,4（8）-二烯的相对含量在48 h达到最高, β-蒎烯的相对含量除72 h外均高于对照;马尾松毛虫幼虫的取食量、排粪量、对食物的消耗和利用指数均有所不同,且随着浓度的升高而降低,而死亡率则表现出与上述指标相反的规律。这说明外源茉莉酸甲酯能够诱导植物的抗虫性。