鱼藤酮气雾剂的加工及其活性测定

用电子喷雾装置测定了鱼藤酮和非洲山毛豆提取物气雾剂对致倦库蚊和德国小蠊的击倒活性。结果表明，20min时，以鱼藤酮和非洲山毛豆粗分物（含鱼藤酮10％）为有效成分的气雾剂对致倦库蚊的击倒率都达到100％，击倒中时分别为10．5min-112．1min；而对德国小蠊的击倒率分别为73．63％-193．62％，击倒中时分别为18．8min-115．7min；说明非洲山毛豆粗分物对德国小蠊的生物活性高于鱼藤酮纯品。二者与右旋胺菊酯混用后，对两种害虫的击倒活性都显著提高。     

鱼藤酮肟氨基羧酸酯的合成、表征及生物活性

以鱼藤酮为原料,经肟化、酯化反应合成了3种鱼藤酮肟氨基甲酸酯类化合物,并用1HNMR对其结构进行了表征。杀虫和抑菌活性测试实验表明,制备的新型鱼藤酮类衍生物具有较高生物活性:N-环己基氨基甲酸鱼藤酮肟酯(Ⅲb)对粘虫(1.00 g/L)的致死率为68.3%,对白粉病菌(0.50 g/L)的抑制率为60.0%。     

紫穗槐种子杀菌活性成分的提取、分离与鉴定

[目的]研究紫穗槐种子中杀菌活性成分。[方法]利用硅胶柱层析,高速逆流色谱法等方法对紫穗槐种子的乙酸乙酯提取物进行分离,并对提取化合物进行杀菌活性测定。[结果]从紫穗槐种子的乙酸乙酯提取物中分离得到7个化合物,分别为5-羟基-7,4’-二甲氧基异黄酮、2’-羟基-4,4’-二甲氧基查耳酮、7,4’-二甲氧基异黄酮、鱼藤酮、11-羟基灰叶素、异灰毛豆酚、异灰叶素。其中鱼藤酮、11-羟基灰叶素、异灰毛豆酚、异灰叶素对黄瓜霜霉活性较好。[结论]紫穗槐中杀菌活性成分主要是鱼藤酮类化合物。     

表鱼藤酮光稳定性的研究

采用HPLC法测定了5’β-表鱼藤酮、5’α-表鱼藤酮、鱼藤酮经365nm紫外光照射后的降解率，降解动力学方程分别为Cr=57．066e^-0.0537t、Ct=13．003e^-0.1748t、Ct=9.0851e^-0.3008t，其半衰期分别为12．9、4．0、2．3h。结果表明在相同时间内鱼藤酮的降解率最高，其次是5’α-表鱼藤酮．5’β-表鱼藤酮的降解率最低。     

鱼藤酮的应用现状及存在问题

鱼藤酮是一种天然的植物质杀虫剂和杀螨剂，主要从热带和亚热带的鱼藤属（Derris）、尖荚豆属（Lonchocarpus）和灰叶属（Tephrosia）植物中提取，其杀虫谱广，害虫不易产生抗药性，为无公害农产品生产推荐使用品种，具有广阔的应用前景。该文简要介绍了鱼藤酮的产品及应用范围、鱼藤酮的应用开发现状以及应用过程中出现的问题和解决方法，并对今后进一步开发应用鱼藤酮提出建议。     

4．8％鱼藤酮·辣椒碱悬浮剂的高效液相色谱分析

建立HPLC法测定4．8％鱼藤酮·辣椒碱悬浮剂中鱼藤酮与辣椒碱含量。采用XDB—C18柱分离，以乙腈-0．1％磷酸溶液为流动相，流速1．0mL／min，外标法定量分析。结果表明：鱼藤酮与辣椒碱的线性相关系数分别为0．9998和0．9999，中间精密度分别为0．15％-1．96％，平均回收率分别为101．16％和102．01％。     

山蒟(Piper hancei Maxim)杀虫活性初步研究

[目的]研究山蒟的杀虫活性,以丰富植物源农药的来源.[方法]采用胃毒法测定山蒟对家蝇的胃毒活性,浸渍法测定山蒟对致倦库蚊和白纹伊蚊的活性.[结果]结果显示:山药的石油醚萃取物表现较强的杀虫活性,石油醚提取物1 g/L处理家蝇12、24 h后,校正死亡率分别为86.66％、90％,处理家蝇12、24、36 h后的LC50值分别为1.4000、0.5000、0.2000 g/L,接近于处理36h后鱼藤酮的LC50值(0.08 g/L).石油醚提取物处理致倦库蚊和白纹伊蚊12h后的LC50值分别为2.4127、10.5163 mg/L,活性分别高于对照药物鱼藤酮的3.1727、21.5100 mg/L.[结论]山蒟具有较好杀虫活性,经检索未见相关文献曾报道山药的杀虫活性.     

新型间二酰胺类杀虫剂的设计、合成及生物活性

为了开发出高活性、低成本的杀虫剂，以溴虫氟苯双酰胺先导化合物，通过活性亚结构拼接法合成出6个间二酰胺类化合物，并经过¹H NMR、¹³C NMR和HRMS等表征手段对目标化合物Ⅰa～Ⅰf的结构进行了确认。室内杀虫、杀螨活性测试结果显示，Ⅰa～Ⅰf对小菜蛾3龄幼虫和二斑叶螨成螨均有不错的活性。对小菜蛾幼虫，Ⅰa和Ⅰe具有最好的活性，在100 mg/L时Ⅰa和Ⅰe都具有100%的杀虫活性，在50 mg/L时Ⅰa和Ⅰe的活性分别是93%,72%。对二斑叶螨成螨，Ⅰa和Ⅰd具有最好的活性，在100 mg/L时Ⅰa和Ⅰd都具有100%的活性，在50 mg/L时Ⅰa和Ⅰd的活性分别是92%,87%。     

含膦酸酯的L-苯丙氨酸二肽衍生物合成与抗肿瘤作用

为了寻找抗肿瘤活性化合物，设计合成了9个含膦酸酯结构的L-苯丙氨酸二肽衍生物，经1H NMR 、13C NMR 和MS对合成的产物进行了结构确认。采用溴化噻唑蓝四氮唑 (MTT) 法对目标化合物进行了体外抗肿瘤活性测试。结果表明：部分目标物对所测肿瘤细胞有增殖抑制作用，呈现潜在的抗肿瘤活性。尤以Ⅲi最为突出，对人肺癌细胞(A549)和人食管癌细胞(EC-109)均有显著抑制作用，IC50分别为6.8±0.9 μ mol/L、7.0±1.2 μ mol/L，与对照药cisplatin接近。     

苯基-二[(三甲基硅基)亚甲基]锡芳香酸酯合成及杀螨活性

合成了两个含硅混合三烃基锡芳香酸酯：苯基-二【（三甲基硅基）亚甲基】锡苯甲酸酯、苯基-二【（三甲基硅基）亚甲基】锡对硝基苯甲酸酯，利用IR、^1H NMR、^13C NMR和元素分析表征了其结构，并进行杀螨活性测定，发现这两个化合物在200mg／L时杀螨率均超过96％，具有较强的杀螨活性。     

三氯化铝催化鱼藤酮异构化制备异鱼藤酮

为了优化鱼藤酮异构化制备异鱼藤酮的工艺。采用三氯化铝催化下异构化。合成收率高达90.5%,较文献提高56%。目标产物经核磁共振谱确证。实验结果表明,三氯化铝催化鱼藤酮异构化的方法可行,反应条件温和。     

固相萃取-高效液相色谱法检测上海青(Brassica chinensis L.)中鱼藤酮的残留动态

[目的]建立固相萃取-高效液相色谱-紫外(SPE-HPLC-UV)检测上海青中鱼藤酮的分析方法,对上海青中鱼藤酮的含量进行动态分析.[方法]样品先经乙腈提取,随后在乙腈提取液中加入氯化钠,盐析后过Florisil固相萃取柱富集净化,再用正己烷-乙醚(体积比3∶7)洗脱,最后以乙腈-水(体积比6∶4)为流动相,在290 nm下用高效液相色谱检测分析上海青中鱼藤酮的含量.[结果]该方法稳定可靠,检测物在0.05～10 mg/L范围内线性关系良好.在0.5～5 mg/kg范围内,平均加标回收率为85.9％～86.3％,检出限为0.05 mg/kg.田间推荐剂量和2倍推荐剂量分别施药,鱼藤酮在上海青中的原始沉积量分别为6.26、18.34 mg/kg.[结论]该化合物在田间降解速率快,在上海青中的半衰期分别为11.2、11.1h.     

Rotenone coprecipitation with biodegradable polymers by supercritical assisted atomization

The aim of this study was to coprecipitate rotenone, a biopesticide, with biodegradable polymers using supercritical assisted atomization (SAA) process. Rotenone encapsulation can protect the pesticide from degradation thus reducing the quantity to be used. Different water soluble polymers were tested, such as polyethylene glycol (PEG), polyvinylpyrrolidone (PVP) and sodium alginate. Solutions with one or two solvents and rotenone suspensions were tested to perform the experiments. Different biodegradable polymer/pesticide ratios were tested: 2 and 8 in the case of PEG⿿rotenone coprecipitates, 25, 50 and 100 in the cases of PVP⿿rotenone and alginate⿿rotenone coprecipitates. The particles obtained were spherical with the mean diameter ranging between 0.6 and 1.5 μm. The effective loading of the particles was evaluated by HPLC and the best results were obtained in the case of alginate⿿rotenone coprecipitates that show a coprecipitation efficiency close to 100% and for PEG⿿rotenone particles the efficiency was about 98%. PVP⿿rotenone composite microparticles showed the lowest coprecipitation efficiency that ranged between 30% and 50%.     

Water-Soluble Coenzyme Q10 Inhibits Nuclear Translocation of Apoptosis Inducing Factor and Cell Death Caused by Mitochondrial Complex I Inhibition

The objectives of the study were to explore the mechanism of rotenone-induced cell damage and to examine the protective effects of water-soluble Coenzyme Q10 (CoQ10) on the toxic effects of rotenone. Murine hippocampal HT22 cells were cultured with mitochondrial complex I inhibitor rotenone. Water-soluble CoQ10 was added to the culture media 3 h prior to the rotenone incubation. Cell viability was determined by alamar blue, reactive oxygen species (ROS) production by dihydroethidine (DHE) and mitochondrial membrane potential by tetramethyl rhodamine methyl ester (TMRM). Cytochrome c, caspase-9 and apoptosis-inducing factor (AIF) were measured using Western blotting after 24 h rotenone incubation. Rotenone caused more than 50% of cell death, increased ROS production, AIF nuclear translocation and reduction in mitochondrial membrane potential, but failed to cause mitochondrial cytochrome c release and caspase-9 activation. Pretreatment with water-soluble CoQ10 enhanced cell viability, decreased ROS production, maintained mitochondrial membrane potential and prevented AIF nuclear translocation. The results suggest that rotenone activates a mitochondria-initiated, caspase-independent cell death pathway. Water-soluble CoQ10 reduces ROS accumulation, prevents the fall of mitochondrial membrane potential, and inhibits AIF translocation and subsequent cell death.     

Intranasal Administration of Rotenone Reduces GABAergic Inhibition in the Mouse Insular Cortex Leading to Impairment of LTD and Conditioned Taste Aversion Memory

The pesticide rotenone inhibits mitochondrial complex I and is thought to cause neurological disorders such as Parkinson’s disease and cognitive disorders. However, little is known about the effects of rotenone on conditioned taste aversion memory. In the present study, we investigated whether intranasal administration of rotenone affects conditioned taste aversion memory in mice. We also examined how the intranasal administration of rotenone modulates synaptic transmission and plasticity in layer V pyramidal neurons of the mouse insular cortex that is critical for conditioned taste aversion memory. We found that the intranasal administration of rotenone impaired conditioned taste aversion memory to bitter taste. Regarding its cellular mechanisms, long-term depression (LTD) but not long-term potentiation (LTP) was impaired in rotenone-treated mice. Furthermore, spontaneous inhibitory synaptic currents and tonic GABA currents were decreased in layer V pyramidal neurons of rotenone-treated mice compared to the control mice. The impaired LTD observed in pyramidal neurons of rotenone-treated mice was restored by a GABA_A receptor agonist muscimol. These results suggest that intranasal administration of rotenone decreases GABAergic synaptic transmission in layer V pyramidal neurons of the mouse insular cortex, the result of which leads to impairment of LTD and conditioned taste aversion memory.     

Mitochondrial Dysfunction and Oxidative Stress Promote Apoptotic Cell Death in the Striatum via Cytochrome c/Caspase-3 Signaling Cascade Following Chronic Rotenone Intoxication in Rats

Parkinson's disease (PD) is a progressive neurological disorder marked by nigrostriatal dopaminergic degeneration. Evidence suggests that mitochondrial dysfunction may be linked to PD through a variety of different pathways, including free-radical generation and dysfunction of the mitochondrial Complex I activity. In Lewis rats, chronic systemic administration of a specific mitochondrial Complex I inhibitor, rotenone (3 mg/kg/day) produced parkinsonism-like symptoms. Increased oxidized proteins and peroxynitrite, and mitochondrial or cytosol translocation of Bim, Bax or cytochrome c in the striatum was observed after 2-4 weeks of rotenone infusion. After 28 days of systemic rotenone exposure, imunohistochemical staining for tyrosine hydroxylase indicated nigrostriatal dopaminergic neuronal cell degeneration. Characteristic histochemical (TUNEL or activated caspase-3 staining) or ultrastructural (electron microscopy) features of apoptotic cell death were present in the striatal neuronal cell after chronic rotenone intoxication. We conclude that chronic rotenone intoxication may enhance oxidative and nitrosative stress that induces mitochondrial dysfunction and ultrastructural damage, resulting in translocation of Bim and Bax from cytosol to mitochondria that contributes to apoptotic cell death in the striatum via cytochrome c/caspase-3 signaling cascade.     

Novel Radiolytic Rotenone Derivative,Rotenoisin B with Potent Anti-Carcinogenic Activity in Hepatic Cancer Cells

Rotenone, isolated from roots of derris plant, has been shown to possess various biological activities, which lead to attempting to develop a potent drug against several diseases. However, recent studies have demonstrated that rotenone has the potential to induce several adverse effects such as a neurodegenerative disease. Radiolytic transformation of the rotenone with gamma-irradiation created a new product, named rotenoisin B. The present work was designed to investigate the anticancer activity of rotenoisin B with low toxicity and its molecular mechanism in hepatic cancer cells compared to a parent compound, rotenone. Our results showed rotenoisin B inhibited hepatic cancer cells’ proliferation in a dose dependent manner and increased in apoptotic cells. Interestingly, rotenoisin B showed low toxic effects on normal cells compared to rotenone. Mitochondrial transmembrane potential has been decreased, which leads to cytochrome c release. Down regulation of anti-apoptotic Bcl-2 levels as well as the up regulation of proapoptotic Bax levels were observed. The cleaved PARP (poly ADP-ribose polymerase) level increased as well. Moreover, phosphorylation of extracellular signal regulated kinase (ERK) and p38 slightly up regulated and intracellular reactive oxygen species (ROS) increased as well as cell cycle arrest predominantly at the G₂/M phase observed. These results suggest that rotenoisin B might be a potent anticancer candidate similar to rotenone in hepatic cancer cells with low toxicity to normal cells even at high concentrations compared to rotenone.     

Resveratrol Partially Prevents Rotenone-Induced Neurotoxicity in Dopaminergic SH-SY5Y Cells through Induction of Heme Oxygenase-1 Dependent Autophagy

Parkinson disease (PD) is a complex neurodegenerative disorder characterized by a progressive loss of dopaminergic neurons. Mitochondrial dysfunction, oxidative stress or protein misfolding and aggregation may underlie this process. Autophagy is an intracellular catabolic mechanism responsible for protein degradation and recycling of damaged proteins and cytoplasmic organelles. Autophagic dysfunction may hasten the progression of neuronal degeneration. In this study, resveratrol promoted autophagic flux and protected dopaminergic neurons against rotenone-induced apoptosis. In an in vivo PD model, rotenone induced loss of dopaminergic neurons, increased oxidation of mitochondrial proteins and promoted autophagic vesicle development in brain tissue. The natural phytoalexin resveratrol prevented rotenone-induced neuronal apoptosis in vitro, and this pro-survival effect was abolished by an autophagic inhibitor. Although both rotenone and resveratrol promoted LC3-II accumulation, autophagic flux was inhibited by rotenone and augmented by resveratrol. Further, rotenone reduced heme oxygenase-1 (HO-1) expression, whereas resveratrol increased HO-1 expression. Pharmacological inhibition of HO-1 abolished resveratrol-mediated autophagy and neuroprotection. Notably, the effects of a pharmacological inducer of HO-1 were similar to those of resveratrol, and protected against rotenone-induced cell death in an autophagy-dependent manner, validating the hypothesis of HO-1 dependent autophagy in preventing neuronal death in the in vitro PD model. Collectively, our findings suggest that resveratrol induces HO-1 expression and prevents dopaminergic cell death by regulating autophagic flux; thus protecting against rotenone-induced neuronal apoptosis.     

Synthesis,characterisation and potential application of deoxycholic acid carboxymethyl chitosan as a carrier agent for rotenone

In the present study, deoxycholic acid carboxymethyl chitosan (DACMC) was synthesised via a two-step reaction, namely carboxymethylation and alkylation. Fourier Transform Infrared (FTIR) Spectrometer, Proton Nuclear Magnetic Resonance (¹H NMR) Spectrometer, Transmission Electron Microscope (TEM) and Thermogravimetric Analyser (TGA) were used to characterise DACMC. Spherical self-aggregates of DACMC micelles with the size ranging from 91.3 to 140.0 nm was observed. DACMC was soluble in pH range studied (1–13), except pH 4. DACMC micelles were formed at critical concentration (CMC) value of 0.468 mg/mL. The ability of DACMC to encapsulate and load rotenone was determined at different weight ratios. The highest value of encapsulation efficiency (EE%) (more than 98%) was obtained for weight ratio of 100:1 (DACMC:Rotenone). The in vitro release data of rotenone-loaded DACMC followed Ritger and Peppas Case II transport mechanism. Results from this study highlight the potential of DACMC to reduce organic solvent application in water-insoluble pesticide production.