厚果鸡血藤提取物对两种同翅目害虫的生物活性

测定了厚果鸡血藤种子和根提取物对褐飞虱和桃蚜两种同翅目害虫的生物活性,结果表明,它们对这两种害虫有很高的触杀活性,对桃蚜有一定的胃毒活性。用不同溶剂提取时,三氯甲烷提取物的活性明显高于甲醇提取物的活性。用相同溶剂提取时,种子提取物的活性比根提取物活性高。对褐飞虱、桃蚜的触杀活性及对桃蚜的胃毒活性均以种子三氯甲烷提取物最高,种子三氯甲烷提取物对褐飞虱、桃蚜的接触LD50值分别为0.25、0.03g/头,对桃蚜的胃毒LC50值为1342mg/L。四种提取物对两种害虫的毒力顺序为:种子三氯甲烷提取物>根三氯甲烷提取物>种子甲醇提取物>根甲醇提取物。     

麻疯树种子提取物对几种害虫的杀虫活性

在室内测定并比较了3种麻疯树种子提取物对同翅目、鳞翅目和鞘翅目害虫桃蚜、菜青虫和米象的杀虫活性。结果显示种子油、种子乙醇提取物和石油醚提取物对3种害虫都具有一定杀虫活性，对桃蚜的触杀活性LC50分别为5．1154、2．0796、13．9882g／L；对米象的杀虫活性LC50分别为8．0243、3．0701、24．3458g／L；种子油和乙醇提取物对菜青虫的胃毒活性LC加分别为18．1043、3．0796g／L，此外这2种提取物对菜青虫也显示出较强的拒食活性；而种子石油醚提取物对菜青虫无明显胃毒活性，拒食活性也很弱。麻疯树种子提取物对3种害虫的相对毒力顺序为乙醇提取物〉种子油〉石油醚提取物。     

黄皮甲醇提取物的除草活性及有效成分研究

[目的]研究黄皮甲醇提取物对稗草的除草活性及其除草有效成分。[方法]采用硅胶柱层析分离及活性跟踪的分离方法。[结果]生物测定结果表明:黄皮甲醇提取物对油菜、萝卜和稗草有很好的生物活性,表明其有效成分为anisolactone和2’,3’-epoxyanisolactone,暂定为黄皮素内酯Ⅰ和黄皮素内酯Ⅱ。毒力测定结果表明:在80 mg/L时,对稗草根长、茎长和鲜质量的抑制率分别为96.00%、84.71%和89.85%。且回归方程的相关系数均达到0.99以上。[结论]黄皮甲醇提取物对稗草有很好的防治效果。     

茚虫威改造物SIOC-Y-047室内生物活性及作用特性评价

[目的]通过茚虫威结构衍生化研究,以期开发出具有自主知识产权的二嗪类杀虫剂新品种。[方法]以黏虫、小菜蛾、斜纹夜蛾为供试靶标,通过室内生物活性测定,发现化合物SIOC-Y-047较其他改造物表现出更好的室内杀虫活性,进一步完成SIOC-Y-047对3种鳞翅目害虫的毒力曲线测定及作用特性评价。[结果]SIOC-Y-047对3个靶标的LC50值分别为1.34、14.05、9.43 mg/L,活性略低于对照药剂茚虫威。室内作用特性与茚虫威相似,以胃毒和触杀作用为主,无根内吸活性。[结论]SIOC-Y-047对鳞翅目害虫黏虫、小菜蛾和斜纹夜蛾均表现良好的室内杀虫活性,活性略低于对照药剂茚虫威。     

八宝景天乙醇提取物对菜青虫的生物活性

[目的]室内测定了八宝景天乙醇提取物对菜青虫3龄幼虫的拒食和触杀作用。[方法]采用小叶碟法和浸渍法分别测定乙醇提取物对菜青虫的拒食和触杀作用。[结果]浸渍法处理对菜青虫3龄幼虫48、72 h的致死中浓度(LC50)分别为7.768、0.183 g/L,且校正死亡率均达100%,24、48 h的拒食率最高分别为99.15%、91.94%,拒食中浓度(AFC50)分别为4.819、15.442 g/L。[结论]八宝景天乙醇提取物对菜青虫3龄幼虫具有较高的拒食和触杀活性,为生物源农药提供了一种新的植物来源。     

17种杀虫剂对细胸金针虫的毒力评价

采用土壤混药法,测定了17种杀虫剂对细胸金针虫的室内毒力.结果表明:供试药剂中苯并吡唑类杀虫剂氟虫腈对细胸金针虫幼虫的毒力最高,LC50值为0.007613 mg/kg土.有机磷类杀虫剂也具有较高的毒力,其中二嗪磷、毒死蜱和辛硫磷的毒力最高,3种杀虫剂的LC50值分别为0.0612、0.1007、0.1230 mg/kg土;哒嗪硫磷和丙溴磷的毒力也较高,其LC50值均低于5 mg/kg土;马拉硫磷和敌百虫对试虫的毒力较低,LC50值分别为6.4887、13.801 8 mg/kg土.氯代烟酰类杀虫剂对试虫也具有较高的毒力,其中氯噻啉对试虫的LC50值为2.638 5 mg/kg土,啶虫脒LC50值为3.2364 mg/kg土,吡虫啉的毒力较低,其LC50值10.8264 mg/kg土.拟除虫菊酯类杀虫剂氯氰菊酯和氰戊菊酯对试虫也具有一定的毒力,其LC50值分别为11.1860、22.289 1 mg/kg土.微生物源杀虫剂阿维菌素和几丁质合成抑剂灭幼脲、杀铃脲和除虫脲对细胸金针虫幼虫的毒力较低,在剂量为 50 mg/kg土时,其校正死亡率均在40%以下.     

五种杀虫剂对小菜蛾的室内生物活性研究

小菜蛾Plutella xylostella是十字花科蔬菜的主要害虫，其造成的为害给蔬菜生产带来巨大损失。本文采用触杀毒力法和摄食毒力法测定了5种新颖的杀虫剂对小菜蛾的室内生物活性，研究结果表明：采用浸渍法处理72h，10％溴虫腈乳油和5．44%丁烯氟虫腈乳油对小菜蛾的触杀活性较好，其LC50值分别为1．758mg／L和2．289mg／L；采用药膜法处理72h，5．44％丁烯氟虫腈乳油和5％锐劲特悬浮剂对小菜蛾表现出了优越的胃毒作用活性，其LC50值分别为0．165mg／L和0．259mg／L。     

荔枝蝽臭液对常见仓储害虫的熏蒸毒力

[目的]鉴于荔枝蝽臭液的特性以及粮食储藏中害虫危害的严峻形势,采用三角瓶密闭熏蒸法探讨了荔枝蝽臭液对常见仓储害虫的熏蒸潜力。[结果]结果表明:荔枝蝽雄虫臭液24 h熏蒸毒力的LC50值分别为米象0.5247μL/L、谷蠧6.3125μL/L、四纹豆象2.4068μL/L、黄斑露尾甲3.7753μL/L;荔枝蝽雌虫臭液24 h熏蒸毒力的LC50值分别为米象0.4803μL/L、谷蠧6.3803μL/L、四纹豆象2.5936μL/L、黄斑露尾甲3.7925μL/L。[结论]荔枝蝽臭液对米象、谷蠧、四纹豆象和黄斑露尾甲等仓储害虫具有很好的熏蒸毒力,可望能从荔枝蝽臭液中筛选出有效的天然熏蒸化合物。     

6种常用杀虫剂对萝卜蚜的毒力测定及田间防效

[目的]采用室内毒力测定和田间药效试验方法,测定6种药剂对萝卜蚜的敏感性。[结果]结果表明萝卜蚜对不同类型杀虫剂敏感性有较大差异,其中95%毒死蜱对萝卜蚜杀虫活性最高,LC50值为0.1215 mg/L,其次为94%阿维菌素,LC50值为0.7795 mg/L,95%高效氯氰菊酯的敏感性最低,LC50值为996.8046 mg/L。通过田间试验可知:10%吡虫啉可湿性粉剂、1.8%阿维菌素乳油、3%啶虫脒可湿性粉剂、1%甲氨基阿维菌素苯甲酸盐乳油、40%毒死蜱乳油和4.5%高效氯氰菊酯乳油对萝卜蚜的防效都非常好,3 d的防效均达98%以上,14 d的防效为100%。[结论]在测试的6中药剂中,目前田间萝卜蚜与桃蚜相比具有较低的抗药性水平。     

桉树叶片提取物的杀虫活性及应用初步研究

采用3种溶剂对桉树叶片进行加热回流提取,分别采用喷雾法和浸渍法测定提取物对鳞翅目害虫黏虫、半翅目害虫蚜虫及蜱螨目害虫朱砂叶螨生物活性。在初筛的基础上,对甲醇、丙酮和石油醚提取物进行了烟蚜复筛及温室盆栽试验。试验结果表明:各提取物对黏虫及朱砂叶螨在10000mg/L的浓度均未表现出杀虫活性,甲醇、丙酮和石油醚提取物对蚜虫均表现出一定的毒杀活性,对烟蚜的LC_(50)值分别为4 644.61、4 276.94、507.47 mg/L,其中石油醚提取物表现出了较高的生物活性。进行了进一步的温室盆栽验证试验,发现药后7 d,10000 mg/L的石油醚提取物对烟蚜的防效达到80.31%,有进一步研究的价值。     

Phenolic compounds and antioxidant activity of extracts of Ginkgo leaves

The aim of the present study was to determine the flavonol contents of crude extracts from Ginkgo (Ginkgo biloba L.) leaves, their antioxidant properties in model system studies, and their inhibitory action of linoleic acid oxidation in an emulsion system and of triacylglycerols (TAG) in rapeseed oil. Extracts were prepared from both green and yellow leaves of Ginkgo trees using water, aqueous acetone, and ethanol. Extracts were analyzed by HPLC for their presence and content of selected flavonols; these included myricetin, quercetin, kaempferol, isorhamnetin, and morin. The highest level of flavonols, especially quercetin, myricetin and kaempferol, were found in the aqueous acetonic extracts. Crude extracts from yellow Ginkgo leaves contained greater amounts of flavonols. The best DPPH radical‐scavenging activity amongst the Ginkgo extracts examined was determined for aqueous acetonic extracts, while the lowest was noted for the ethanolic extract of green leaves. Water infusion extracts exhibited the highest iron(II) chelating activity. The reducing power of extracts from yellow leaves was 2 higher than that of crude extracts from green leaves. Nevertheless, extracts from green Ginkgo leaves imparted a greater protection factor against TAG oxidation, as assessed by the Rancimat method. Crude extracts from yellow Ginkgo leaves were more efficacious than green ones at inhibiting oxidation of the linoleic acid emulsion.     

Kairomones Extracted from Rice Yellow Stem Borer and their Influence on Egg Parasitization by <Emphasis Type="Italic">Trichogramma japonicum</Emphasis> Ashmead

Host location and acceptance by egg parasitoids can be mediated by close-range host stimuli. In this study, we tested the response of Trichogramma japonicum Ashmead to cuticular extracts of adult and larval rice yellow stem borer (YSB), Scripophaga incertulas Walker. We also studied the wasps’ response to extracts from YSB larval frass. Laboratory bioassays revealed that hexane extracts of the adult host body stimulate ovipositor probing of T. japonicum. Extracts of larval frass also stimulated parasitization. In contrast, host larval cuticular extracts had no effect on parasitization rates. Fractionation of the crude extracts of adult YSB cuticular extracts was performed using silica gel chromatography, followed by bioassays of the individual fractions to test their effects on wasp behavior. Analyses of the most active fractions by gas chromatography–mass spectrometry revealed that the extract contained saturated long chain alkanes and alkenes, with carbon numbers ranging from C₂₀ to C₃₂. Hydrocarbons were applied onto host eggs to test their effects on parasitization rates. Treatments of eggs with docosane, tetracosane, pentacosane, and eicosane enhanced host egg parasitization, while pentadecane, hexadecane, and nonadecane deterred oviposition. An erratum to this article can be found at     

姬松茸发酵条件及其菌丝水提物抗黄瓜黑星病的研究

对姬松茸(Agaricus blazei Murrill)发酵条件及其菌丝水提物对黄瓜黑星病的诱导抗病性进行了研究. 为得到菌丝发酵的最大生物量,通过正交试验确定了姬松茸的液体发酵培养基配方为(%)：玉米淀粉3.50,酵母粉0.30, KH2PO4 0.20, MgSO4×7H2O 0.15, CaCl2 0.05, 玉米浆0.2. 于25oC发酵8 d,生物量达到8.65 g/L. 经黄化子叶喷雾接种法测定,姬松茸菌丝水体物对黄瓜黑星病的平均诱导抗病效果为74.04%. 毒性测定结果表明,该产物按农药分级属于低毒. 证明了姬松茸菌丝水提物是一种高效低毒的生物农药.     

亚麻织物的天然染料栀子黄无媒染工艺研究

以水为溶剂提取栀子黄,并用该提取液对亚麻织物进行染色,通过实验确定了栀子黄提取和直接染色的最佳工艺.为了提高栀子黄对亚麻织物的上染率和染色牢度,选用了固色刺NMR-1进行处理,以取代传统的媒染工艺,并对影响固色效果的主要因素进行了探讨,获得了优化工艺.结果表明,在优化的工艺条件下,固色处理可以明显改善栀子黄对亚麻织物的染色性能,其效果优于媒染工艺.     

提高硅钼黄比色溶液稳定性的研究

试验、分析和总结了影响β硅钼黄稳定性的显色条件、溶液组成及稳定剂的选用等诸多因素。发现丙酮的稳定效果比乙醇好,且没有光化学还原干扰。试验表明,在pH,0.6～1、钼酸铵含量为0.8%～1.2%、丙酮含量为5%～10%、大体积显色所形成的β硅钼黄在30,℃以下能稳定4,h以上,且重现性好,能较好地满足分析要求。用氟化钾和硼酸进行解聚处理后的试液,若在玻璃容量瓶中显色并放置,氟仍会侵蚀玻璃,引起干扰。研究改进后的硅钼黄法,其准确度和精密度与抗坏血酸还原-硅钼蓝法相似,分析微量二氧化硅S≤0.014%、RSD≤1.5%,但比硅钼蓝法快速、简便、节省试剂。     

Antioxidative effect of ethanol tea extracts on oxidation of canola oil

There is an increasing interest in the biological effects of natural antioxidants present in teas on formation ofin vivo free radicals, carcinogenesis, and atherogenesis. Teas are traditionally classified into six major groups, namely, green, yellow, white, black, dark-green, and oolong teas. The present study examined the antioxidative activity of ethanol extracts from these six major groups of teas against oxidation of heated canola oil. The oxidation was conducted at 100°C by monitoring oxygen consumption and changes in linoleic and linolenic acids in canola oil. The ethanol extracts of green, yellow, and white teas strongly inhibited oxidation of canola oil compared to butylated hydroxytoluene, probably due to the presence of natural polyphenols. In contrast, oolong teas examined exhibited only moderate antioxidative activity because of the partial destruction of natural polyphenols by semifermentation. The ethanol extracts of black, dark-green, and ginseng teas studied showed little or no protection to canola oil from lipid oxidation, probably due to the complete destruction of natural polyphenols by fermentation during manufacturing processes.     

天然植物紫外线防护效果研究

为探索天然植物在防晒化妆品中的应用,选择天然植物提取物根皮素、白藜芦醇和熊果苷,研究其安全性及紫外线防护效果。采用紫外分光光度法测定天然植物提取物的紫外吸收特征,同时将其复配成防晒产品。在采用封闭式斑贴试验评价防晒产品安全性的基础上,应用人体试验测定产品防晒指数(SPF值)和长波紫外线防护指数(PFA值)。结果发现,3种植物提取物表现出不同的紫外吸收能力,中波紫外线(UVB)波段吸收效果优于长波紫外线(UVA)波段,且白藜芦醇的紫外吸收效果相对最好;人体斑贴试验证明3种天然植物提取物均具有良好的皮肤适应性;防晒效果人体试验显示白藜芦醇和根皮素令SPF值有较为明显的提高。研究表明,部分天然植物提取物表现出良好的紫外线防护效果,且与传统的化学和物理防晒剂相比,具有皮肤刺激性小、光化学稳定、安全可靠等优点,具有广阔的市场前景。     

Detection and Semi-Quantification of Lipids on High-Performance Thin-Layer Chromatography Plate Using Ceric Ammonium Molybdate Staining

It is desirable to quickly check the composition of lipids in small size samples, but achieving this is challenging using the existing staining methods. Herein, a highly sensitive and semi-quantitative method is developed for analysis of lipid samples with ceric ammonium molybdate (CAM) staining. The CAM detection method is systematically evaluated with a wide range of lipid classes including phospholipids, sphingolipids, glycerolipids, fatty acids (FA), and sterols, demonstrating high sensitivity, stability, and overall efficiency. Additionally, CAM staining provides a clean yellow background in high performance thin-layer chromatography (HPTLC) which facilitates quantification of lipids using image processing software. Lipids can be stained with CAM reagent regardless of their head group types, position of the carbon–carbon double bonds, geometric isomerism, and the variation in the length of FA chain, but staining is mostly affected by the degree of unsaturation of the FA backbone. The mechanism of the CAM staining of lipids is proposed on principles of the reduction–oxidation reaction, in which Mo(VI) oxidizes the unsaturated lipids into carbonyl compounds on the HPTLC plate upon heating, while itself being reduced to Mo(IV). This method is applied for the separation, identification, and quantification of lipid extracts from porcine brain. Practical applications: The CAM staining method that is developed in this work shows a high sensitivity for diverse lipid classes following HPTLC separation. HPTLC with CAM staining is a promising method for quick assessment of the identity and quantity of diverse lipid classes in lipid extracts of small size biological samples.     

2000 t/a精制低砷黄磷系统工业性试验

概述了以工业精黄磷为原料,采用二次精制技术脱除黄磷中杂质砷的２０００ｔ／ａ精制低砷黄磷系统的工艺流程和工业性试验结果。工业性试验表明：该系统具有工艺流程简单、工艺技术指标稳定、生产过程安全性好等特点,可使黄磷中杂质砷含量由１４５ｍｇ／ｋｇ降至２．０ｍｇ／ｋｇ,脱砷率达９８％。     

分光光度法测定煤沥青中硅含量

研究了分光光度法测定煤沥青中硅含量,试样经灰化后与碳酸钠高温熔融生成可溶性硅酸盐,与钼酸铵反应生成硅钼黄,在强酸性条件下用硫酸亚铁铵还原为硅钼蓝,在波长810nm下有最大吸收,用标准曲线法定量。进行了显色反应条件试验以及精密度试验、回收率试验、对照试验,方法的加标回收率为91%～105%,相对标准偏差(RSD)小于7%。