40种植物丙酮提取物对朱砂叶螨的毒杀活性

为推动植物源杀螨剂的研发进程,采用玻片浸渍法测定40种植物丙酮提取物对朱砂叶螨（Tetranychus cinnabrinus）雌成螨的毒杀活性,以期发现具开发潜力的植物资源。结果表明,沙茴香（Ferula bungeana）、盐肤木（Rhus chinensis）、黄连木（Pistacia chinensis）、紫丁香（Syringa oblata）和南方六道木（Abelia dielsii）等5种植物丙酮提取物对朱砂叶螨的毒杀活性较好;毒力测定表明,沙茴香和盐肤木丙酮提取物对朱砂叶螨的毒杀活性最好,LC₅₀分别为0.08 g·mL^-1和0.09 g·mL^-1。可见,沙茴香和盐肤木可作为植物源杀螨剂研发的候选材料,值得进一步研究。     

东莨菪内酯与双脱甲氧基姜黄素对朱砂叶螨致死效应模拟

采用玻片浸渍法测定了植物源杀螨活性物质东莨菪内酯、双脱甲氧基姜黄素及两者联合作用最佳增效配比(东:双=7:6)对朱砂叶螨雌成螨的致死效应,并采用时间-剂量-死亡率(TDM)模型进行模拟.结果表明:所建TDM模型均通过Hosmer-Lemoshow拟合异质性检验,朱砂叶螨雌成螨对3种药剂浓度变化的敏感程度为东莨菪内酯＞两者最佳配比＞双脱甲氧基姜黄素,双脱甲氧基姜黄素、东莨菪内酯和两者最佳配比对朱砂叶螨雌成螨的致死率高峰期分别为处理后32、28和32 h;处理后48 h的LC50和LC90分别为0.3324、0.2035、0.2195mg·mL-1和2.1198、0.9521、1.1617 mg·mL-1;浓度为1.0和2.0 mg·mL-1处理下,LT50分别为7.4、6.0、6.1h和6.4、4.8、5.0h.因此,东莨菪内酯与双脱甲氧基姜黄素最佳配比和东莨菪内酯具有相近的杀螨动态及时间-剂量效应,表现出较好的杀螨活性和增效作用,具有一定的开发利用价值.     

木鳖子提取物对朱砂叶螨的触杀活性

测定了木鳖子提取物对朱砂叶螨的触杀活性。用甲醇、氯仿、石油醚3种不同极性的溶剂提取,石油醚提取率最高为30.79%,且对朱砂叶螨成螨和卵的触杀活性均高于其他两种溶剂的提取物,24 h校正死亡率分别为77.52%和72.04%。用甲醇对石油醚提取物萃取,发现甲醇萃取物活性明显高于石油醚部分,对成螨和卵处理24 h后的校正死亡率分别为89.60%和74.65%,产卵抑制率为62.74%,驱避率为58.23%。柱层析对甲醇萃取物进行分离得到10种组分,组分5活性最高,浓度为2 mg/mL时,24 h校正死亡率为86.15%。用薄层层析和气相色谱质谱联用仪分别检测组分5纯度和主成分,初步确定活性成分为α-菠菜甾醇。     

朱砂叶螨的交配行为

先羽化的雄螨有主动帮助雌螨蜕皮的行为,待雌螨蜕出蛹蜕即与其交配。交配时雄体在下方,锥形腹端翻转向上与雌体交接。初羽化雌螨交配时间多在2分钟以上,而羽化日久的雌螨,交配时间明显缩短。雌雄螨一生均多次交配。交配能刺激雌螨产卵,并使雌性比增加。     

朱砂叶螨越冬的研究

朱砂叶螨(Tetranychus cinnabarinus)原多混同于二斑叶螨(T.urticae),为世界性害螨,在我国严重危害棉花、瓜、豆、茄果类蔬菜及许多观赏植物。叶螨科叶螨属的很多种类以滞育态雌成螨     

朱砂叶螨密度效应研究

研究朱砂叶螨密度效应的结果表明,朱砂叶螨在卵期不存在密度作用,平均孵化率可达96.01％。但在幼若螨期,高密度则将导致较高的死亡率并调节种群的性比值。羽化成螨种群中雌性比例增加,但子代成螨则表现雄性比例的显著增大。雌成螨密度不同,产卵量和寿命均有显著差别。当雌成螨密度超过3头/cm~2时表现较强的扩散性。     

朱砂叶螨滞育诱导的研究

朱砂叶螨滞育诱导反应曲线为长日照型,临界光照长度为9小时45分。15℃条件下诱导,0～1小时30分和11～24小时光照时无滞育发生,光照6小时15分至9小时45分则几乎完全滞育。后若螨期和成螨期具光敏感性,最敏感虫态是成螨期。诱导其他虫态,滞育不发生。     

柑桔提取物中主要成分的杀螨活性评价

【目的】研究柑桔提取物中主要杀螨活性成分,为柑桔提取物作为杀螨剂的使用奠定基础。【方法】采用乙醇、丙酮、乙酸乙酯、石油醚4种溶剂对北碚447的果皮与种子进行平行提取,对4种提取物进行杀螨活性评价。对北碚447的果皮乙醇提取物和乙酸乙酯提取物进行GC-MS分析,就其中主要成分进行杀螨活性评价,确定主要杀螨活性成分。【结果】发现柑桔乙醇提取物的杀螨活性最高;果皮提取物的杀螨活性高于种子;果皮和种子乙醇和乙酸乙酯提取物通过GC-MS分析共鉴定出35种成分,其中柠檬烯含量最高,和柠檬醛、4-松油醇、芳樟醇占提取物含量的85%以上;柠檬烯杀螨活性高于柠檬醛、松油醇、芳樟醇、?-蒎烯。【结论】柑桔提取物中主要的杀螨成分是柠檬烯、柠檬醛、4-松油醇、芳樟醇、?-蒎烯,以这些物质为主要有效成分的柑桔提取物类杀螨剂的研发具有重大意义。     

十种杀螨剂对朱砂叶螨不同发育阶段的毒力比较

[目的]为明确不同杀螨剂对朱砂叶螨Tetranychus cinnabarinus不同发育阶段的生物活性.[方法]采用浸渍法分别测定了10种杀螨剂对朱砂叶螨成螨、卵和若螨的毒力.[结果]丁氟螨酯、阿维菌素和联苯肼酯对成螨、卵和若螨的活性均较高;乙螨唑和螺螨酯对卵和若螨活性较高,但对成螨活性明显偏低;甲氰菊酯对成螨和若螨...     

旋覆花提取物对朱砂叶螨的生物活性及酶活性的影响

本文研究了旋覆花石油醚提取物对朱砂叶螨的毒力作用及其对相关酶活性的影响。结果表明：旋覆花石油醚提取物的杀螨活性较高,浓度为2mg?mL-1 时,校正死亡率达到92.05％。通过对旋覆花石油醚提取物进一步萃取、柱层析分离、薄层层析,发现最终得到的38个流分中,杀螨效果较好的是流分7,其校正死亡率为85.53%。流分7经GC/MS鉴定为羽扇豆醇,其校正死亡率达到66.46%。进一步测定羽扇豆醇对朱砂叶螨谷胱甘肽-S-转移酶、Ca2 -ATPase、过氧化物歧化酶的活性以及总蛋白含量的影响,结果表明经羽扇豆醇处理后,螨体内过氧化物歧化酶被激活,而谷胱甘肽-S-转移酶和Ca2 -ATPase均受到不同程度的抑制,蛋白总量在这个过程中没有明显的变化。上述结果表明旋覆花提取物羽扇豆醇可以有效地杀死朱砂叶螨,这为旋覆花作为新型植物源农药提供一定的理论依据。     

Antifungal activity of Artemisia annua endophyte cultures against phytopathogenic fungi.

Artemisia annua, well recognized for its production of antimalarial drug artemisinin, is seldom attacked by any of phytopathogenic fungi, which could be partially associated with the presence of endophytes. Present investigation is aiming at disclosing whether the endophytes inside A. annua produce antifungal substances. A total of 39 endophytes were isolated and fermented, and the ferment broth was evaluated in vitro for the antifungal activity against crop-threatening fungi Gaeumannomyces graminis var. tritici, Rhizoctonia cerealis, Helminthosporium sativum, Fusarium graminearum, Gerlachia nivalis and Phytophthora capsici. These plant pathogens are still causing wheat take-all, sharp eyespot, common rot, scab, snow mould, and pepper phytophthora blight, respectively. Out of 39 endophytes investigated, 21 can produce in vitro substances that are inhibitory to all or a few of the tested phytopathogens whereas the rest yielded nothing active. Moreover, the most active broth of endophyte IV403 was extracted with EtOAc and n-butanol, and comparisons of the antifungal activity of the extracts indicated that the major active metabolites were EtOAc-extractable.     

Acaricidal activities of extracts of Kochia scoparia against Tetranychus urticae, Tetranychus cinnabarinus, and Tetranychus viennensis (Acari: Tetranychidae)

Extracts of an annual herbaceous plant, Kochia scoparia (L.) Schrad (Macrophomina), were bioassayed to determine their acaricidal activities against Tetranychus urticae Koch, Tetranychus cinnabarinus (Boisduval), and Tetranychus viennensis Zacher (Acari: Tetranychidae) in the laboratory. Extracts had both contact and systemic toxicity to these mites. Three solvents were tested for preparing crude extracts: petroleum ether, chloroform, and methanol. Methanol was the most effective solvent, extracting 3.11-4.53% of the acaricide. Petroleum ether was the least effective solvent, extracting 1.25-1.54%. However, extracts with chloroform resulted in the highest mite mortality (78.86%), and ultrasound-assisted extraction required the least time (10 min). Concentrated extracts were prepared using chloroform, methyl acetate, or distilled water as a solvent. Mite mortalities from the concentrated extracts by methyl acetate or distilled water were significantly lower than those by chloroform. The mean lethal concentrations (LC50) of the extracts by chloroform, methyl acetate, and distilled water to the mites were 0.71 +/- 0.06, 2.08 +/- 0.16 and 8.75 +/- 0.062 mg/ml, respectively. After liquid chromatography and thin layer chromatography, the concentrated extracts by chloroform were separated into seven groups of isolated fractions and tested for acaricidal activity.     

艾蒿提取物对菜青虫的生物活性

采用微波辅助提取、溶剂浸提 ,以正己烷、乙醇、正己烷 +乙醇 (体积比 1∶1 )为溶剂从艾蒿ArtemisiaargyiL啨ｖｌ.etVant茎叶得到了提取物。另外 ,还用水蒸气蒸馏法获得了精油。生物活性试验表明 ,它们对菜青虫PierisrapaeL .具有较强的拒食活性和一定的触杀活性。其中 ,正己烷为溶剂的微波辅助提取物的拒食活性和触杀活性最强。     

Protective Effect of Artemisia annua L. Extract against Galactose-Induced Oxidative Stress in Mice

Artemisia annua L. (also called qinghao) has been well known as a source of antimalarial drug artemisinins. In addition, the herb was reported to have in vitro antioxidative activity. The present study investigated the protective effect of aqueous ethanol extract of Qinghao (AA extract) against D-galactose-induced oxidative stress in C57BL/6J mice. Feeding AA extract-containing diet lowered serum levels of malondialdehyde and 8-OH-dG that are biomarkers for lipid peroxidation and DNA damage, respectively. Furthermore, AA extract feeding enhanced the activity of NQO1, a typical antioxidant marker enzyme, in tissues such as kidney, stomach, small intestine, and large intestine. In conclusion, AA extract was found to have antioxidative activity in mouse model.     

瑞香狼毒根提取物对山楂叶螨的生物活性

采用不同的生物活性测定方法比较了瑞香狼毒(Stellera chamaejasme L.)根部4种不同溶剂提取物的杀螨活性。结果表明,瑞香狼毒根提取物对山楂叶螨(Tetranychus viennensis Zacher)有很好的触杀和内吸活性。在触杀活性测试中,石油醚提取物和氯仿提取物的杀螨活性最高;在内吸作用中,乙醇、氯仿和石油醚提取物的杀螨活性均较高,杀螨效果显著。在对石油醚提取物的不同溶剂萃取物进行生物活性追踪测定中发现,石油醚萃取物和氯仿萃取物具有较高的生物活性,浓度为0.6 g.L-1,山楂叶螨的24 h校正死亡率分别达到93.22%和79.66%。     

Phytochemical,acaricidal and biological activity of Dodonaea viscosa L. against the two spotted spider mite Tetranychus urticae Koch

Alcohol extract, saponins and flavones fractionated from Dodonaea viscosa leaves were tested for their acaricidal activity against the adult females of Tetranychus urticae Koch. It was found that crude alcohol extract was more potent than the isolates obtained. At LC₅₀ and LC₉₀ levels, the crude extract ranked the first. All the biotic factors are significantly affected. The fecundity was seriously reduced however, the hatchability of eggs was not affected. Two flavonoids were identified as Querectin 3–0-glucose 7-0-rhamnoside and the other as Querectin 3-0 arabinose 7-0 rhammoside from the ethyl acetate fraction of the alcohol extract.     

40种杂草的丙酮提取物对3种植物病原真菌的抑菌活性

在离体条件下研究了40种杂草的丙酮提取物对辣椒疫霉(Phytophthora capsici Leonian)、尖孢镰刀菌(Fusarium oxysporium Schl.)和灰葡萄孢(Botrytis cinerea Pets.)3种植物病原真菌的抑菌活性.结果表明,有7种杂草的丙酮提取物至少对1种供试病原菌的抑制率在60%以上.其中,黄花蒿(Artemisia annua L.)、苍耳(Xanthiumsibiricum Patrin)和荔枝草(Salvia plebeia R. Br.)的丙酮提取物对3种病原菌的抑制率都在60%以上;鳢肠(Ecliptaprostrata L.)的丙酮提取物对辣椒疫霉和尖孢镰刀霉的抑制率在60%以上;车前(Plantago asiatica L.)、夏至草[Lagopsis supina(Steph.)IK.-Gal.]和泽漆(Euphorbia helioscopia L.)的丙酮提取物对灰葡萄孢的抑菌效果较好.     

Structural and functional characterization of HMG-COA reductase from Artemisia annua

Plants synthesize a great variety of isoprenoid products that are required not only for normal growth and development but also for their adaptive responses to environmental challenges. However, despite the remarkable diversity in the structure and function of plant isoprenoids, they all originate from a single metabolic precursor, mevalonic acid. The synthesis of mevalonic acid is catalysed by the enzyme, 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMG- CoA reductase). The analysis of the amino acid sequence of HMG-CoA reductase from Artemisia annua L. plant showed that it belongs to class I HMG-CoA reductase family. The three dimensional structure of HMG-CoA reductase of Artemisia annua has been generated from amino acid sequence using homology modelling with backbone structure of human HMG-CoA reductase as template. The model was generated using the SWISS MODEL SERVER. The generated 3-D structure of HMG-CoA reductase was evaluated at various web interfaced servers to checks the stereo interfaced quality of the structure in terms of bonds, bond angles, dihedral angles and non-bonded atom-atom distances, structural as well as functional domains etc. The generated model was visualized using the RASMOL. Structural analysis of HMG-CoA reductase from Artemisia annua L. plant hypothesize that the N and C-terminals are positioned in cytosol by the two membrane spanning helices and the C-terminals domain shows similarity to the human HMG-CoA reductase enzyme indicating that they both had potential catalytic similarities.     

Activity of Artemisia annua and artemisinin derivatives,in prostate carcinoma

BackgroundArtemisia annua L, artemisinin and artesunate reveal profound activity not only against malaria, but also against cancer in vivo and clinical trials. Longitudinal observations on the efficacy of A. annua in patients are, however missing as of yet.MethodsClinical diagnosis was performed by imaging techniques (MRT, scintigraphy, SPECT/CT) and blood examinations of standard parameters from clinical chemistry. Immunohistochemistry of formalin-fixed, paraffin-embedded tumor material was performed to determine the expression of several biomarkers (cycloxygenase-2 (COX2), epidermal growth factor receptor (EGFR), glutathione S-transferase P1 (GSTP1), Ki-67, MYC, oxidized low density lipoprotein (lectin-like) receptor 1 (LOX1), p53, P-glycoprotein, transferrin receptor (TFR, CD71), vascular endothelial growth factor (VEGF), von Willebrand factor (CD31)). The immunohistochemical expression has been compared with the microarray-based mRNA expression of these markers in two prostate carcinoma cell lines (PC-3, DU-145).ResultsA patient with prostate carcinoma (pT3bN1M1, Gleason score 8 (4+4)) presented with a prostate specific antigen (PSA) level >800 µg/l. After short-term treatment with bacalitumide (50 mg/d for 14 days) and long-term oral treatment with A. annua capsules (continuously 5 × 50 mg/d), the PSA level dropped down to 0.98 µg/l. MRT, scintigraphy and SPECT/CT verified tumor remission. Seven months later, PSA and ostase levels increased, indicating tumor recurrence and skeletal metastases. Substituting A. annua capsules by artesunate injections (2 × 150 mg twice weekly i.v.) did not prohibit tumor recurrence. PSA and ostase levels rose to 1245 µg/l and 434 U/l, respectively, and MRT revealed progressive skeletal metastases, indicating that the tumor acquired resistance. The high expression of MYC, TFR, and VEGFC in the patient biopsy corresponded with high expression of these markers in the artemisinin-sensitive PC-3 cells compared to artemisinin-resistant DU-145 cells.ConclusionLong-term treatment with A. annua capsules combined with short-term bicalitumide treatment resulted in considerable regression of advanced metastasized prostate carcinoma. Controlled clinical trials are required to evaluate the clinical benefit of A. annua in prostate cancer.     

微生物发酵青蒿叶和叶渣的研究

为扩大青蒿原料的应用途径,延伸青蒿产业链,对青蒿叶和叶渣进行发酵研究.拟开发可用于动物保健的青蒿来源的产品.采用微生物发酵青蒿及青蒿叶渣,检测枯草芽孢杆菌、酿酒酵母菌、植物乳杆菌等菌株发酵青蒿叶和叶渣后其粗蛋白、粗脂肪、粗纤维素以及青蒿素、青蒿乙素、双氢青蒿酸、青蒿酸含量变化.青蒿叶发酵产物及功效成分含量与对照组比较,...