Pepper 9- and 13-lipoxygenase genes are differentially activated by two tobamoviruses and by hormone treatments

Two novel pepper 13-lipoxygenase (LOX) genes were cloned and their expressions were compared with those of three 9-LOX genes in pepper leaves inoculated with two different tobamoviruses. Obuda pepper virus (ObPV) inoculation led to a massive induction of pathogenesis-related genes and to the development of hypersensitive reaction (incompatible interaction), while Pepper mild mottle virus (PMMoV) inoculation resulted in a compatible interaction. Both virus infections markedly activated the expression of the two novel 13-LOXs. The magnitudes of induction of 13-LOXs did not differ substantially between the ObPV- and PMMoV-inoculated leaves. The induction of three 9-LOXs was markedly more robust and rapid in ObPV-inoculated leaves than in PMMoV-inoculated ones. LOXs were very differentially activated in pepper leaves treated with defense hormones. A large number of hormone-related cis-regulatory elements were identified in the promoter regions of LOXs. ObPV inoculation resulted also in the substantial up-regulation of an omega-6-fatty acid desaturase gene. Our results suggest that 9-LOX-dependent pathways are more probably involved in the suppression of virus replication than 13-LOX-dependent plant responses.     

烟草青枯病菌噬菌体分离及其生物学特性研究

【目的】烟草青枯病是我国南方烟区发生普遍而严重的细菌病害,目前尚未有理想的化学防治药剂,筛选青枯病菌噬菌体,为作物青枯病的防治提供噬菌体资源。【方法】从江西省吉安市烟田采集土壤样本,采用双层平板培养分离方法,分离青枯菌噬菌体,进一步比较物理和化学因素对噬菌体活性的影响。【结果】从吉安烟田土壤中分离获得6个青枯菌噬菌体,编号为PTb7-1、PTb1521、PTb1553、P1Tb1556、P2Tb1556和PTb574,其生物学特性存在差异。结果显示,多个噬菌体的最适生长温度约为35℃,致死温度为55～60℃,适宜酸碱度为pH 5～9,且对紫外光、乙醚和氯仿敏感。然而,噬菌体PTb7-1只适合于酸性环境条件下生长繁殖,噬菌体P2Tb1556对紫外光和乙醚不敏感,但对氯仿敏感。【结论】烟草土壤中具有丰富的青枯菌噬菌体资源,是筛选噬菌体的材料来源。6个青枯菌噬菌体生物学特性存在差异,噬菌体P2Tb1556对紫外光和乙醚不敏感,但对氯仿敏感。     

超高效液相色谱———液相荧光法测定果蔬中壬基酚聚氧乙烯醚及其降解产物

建立了热带水果中环境激素壬基酚聚氧乙烯醚及其降解产物壬基酚的超高效液相色谱测定方法。以乙酸乙酯为提取溶剂,高速匀浆后,滤液以炭黑石墨氨基柱净化浓缩,以 C18 色谱柱进行分离,经液相色谱荧光法测定,结果表明：样品中壬基酚聚氧乙烯醚及壬基酚在0.2～50 μg/mL 范围内线性良好,其方法检出限分别为2、1.6 μg/kg, 回收率NP 在 91％～104％之间,NPEO在75％～83％之间。该方法快速灵敏,准确度高,符合残留检测要求。     

石油醚除脂处理对香菜总黄酮提取的影响

石油醚除脂处理是目前植物黄酮类物质提取中常用的处理环节。为确定石油醚除脂处理对黄酮类物质提取的影响,以香菜（Co-riandrum sativum L.）叶片为材料,进行了石油醚除脂处理的对比研究,并对石油醚除脂时长进行分析。结果表明：对乙醇热回流提取初提物进行石油醚除脂处理后黄酮提取率高于未除脂的对照,具有显著差异;石油醚除脂时间以1.5h为宜,时长对结果影响较小。在黄酮类物质提取纯化工艺中,应在初提后纯化精制前进行石油醚除脂处理。     

高纯度正丁醚及其杂质的气相色谱测定方法

利用气相色谱,针对正丁醇脱水法制备的高纯度正丁醚的纯度及其所含杂质开展研究,利用阿皮松L作固定液,Chromosorb P作担体,在氢火焰检测器上,采用面积归一化法,同时测得正丁醇脱水法制备的正丁醚中杂质正丁醇、丁醛、正丁烯-1的含量;利用GDX501与GDX101混合柱,选用热导检测器,采用外标法测定正丁醚中微量水份,并计算正丁醇纯度。该方法操作简便,可用于生产控制、产品分析,同时可用作环境正丁醚污染源分析。     

An update on the therapeutic role of alkylglycerols

Scandinavian folk medicine used shark liver oil for the treatment of cancers and other ailments based on the rarity of tumors in sharks and their ability to resist infections. Shark liver oil is a source of alkylglycerols which have been studied as anti-cancer agents in several clinical trials. Moreover, alkylglycerols have been investigated for the treatment of radiation induced side effects and for their ability to boost the immune system. Several experimental studies have shown the ability of alkylglycerols to open the blood brain barrier to facilitate the access of therapeutic drugs to the central nervous system. This review covers the most important studies of alkylglycerols in both animals and humans.     

电子垃圾回收地散养家禽（鸡）中多溴联苯醚（PBDEs）的浓度与分布模式

测定了广东清远电子垃圾回收地周围农户散养的17只公鸡和16只母鸡中17种PBDEs在肌肉及肝脏组织中的浓度与分布模式,PBDEs在公鸡肉、肝和母鸡肉、肝中的浓度范围分别为4.4～4 382.9 ng/g（脂肪归一化后浓度,后同）,3.6～7 916.5ng/g和3.2～178.6 ng/g,0.7～395.8ng/g。结果表明：母鸡肌肉、肝脏中PBDEs浓度稍低于公鸡的相应组织,但无统计意义上的显著差异;公鸡、母鸡肌肉组织中PBDEs浓度显著高于肝脏中浓度。浓度对比结果显示,研究地区鸡肉中PBDEs的浓度高于其他区域的报导值,表明电子垃圾回收活动释放的PBDEs在家禽（鸡）中得到了一定程度的积累。多溴联苯醚各同系物在肉与肝脏的分布模式基本相似,主要以高溴的BDE209、BDE207、BDE206、BDE208,以及低溴的BDE47、BDE99为主,其他成分所占比例较小。相对于鸡肝,鸡肉更容易富集低溴代的多溴联苯醚。     

甲基叔丁基醚对斑马鱼及中国仓鼠卵巢细胞的毒性效应

[目的]研究甲基叔丁基醚(MTBE)对斑马鱼和中国仓鼠卵巢细胞的毒性作用及氧化应激效应,为其科学、合理应用提供依据。[方法]应用半静态试验法研究不同浓度MTBE对斑马鱼的急性毒性效应,以中国仓鼠卵巢(CHO)细胞为模型,分析不同浓度MTBE对CHO细胞增殖水平和氧化应激相关酶活力水平的影响。[结果]MTBE对斑马鱼的48 h LC50值为71.5 mg/L;在细胞试验中,当MTBE暴露浓度高于5.0 mmol/L时,CHO细胞增殖水平受到明显抑制(P0.05);当MTBE暴露浓度达到50.0 mmol/L时,SOD活力明显上升(P0.05)。当MTBE浓度达到25.0 mmol/L时,CAT活力达到最大值且与对照组差异显著(P0.05);当MTBE浓度达到25.0 mmol/L时,CHO处理组GSH-Px活力明显上升(P0.05)。[结论]MTBE暴露可以诱导斑马鱼和CHO细胞的毒性作用,而氧化应激酶活力水平的改变可能是MTBE毒性作用之一。