0.5%氨基寡糖素AS对烟草TMV的抑制及作用机制的初步研究

研究了0．5％氨基寡糖素AS（净土灵）6．25mg/L对烟草花叶病毒（TMV）枯斑寄主心叶烟（Nicotiana glutinosa）的预防、治疗和钝化作用及其在烟草上引起的寄主体内防御酶系变化。结果表明，0．5％氨基寡糖素AS喷施24h后接种TMV，对烟草花叶病毒的预防效果为58．5％，对烟草花叶病毒侵染的治疗效果达43．6％，对烟草花叶病毒的钝化效果为11．8％。同时，0．5％氨基寡糖素AS处理可导致烟草品种K326叶片的PAL、POD、SOD活性不同程度提高，表明0．5％氨基寡糖素AS可以诱导烟草对TMV的抗性，提高烟草的免疫能力。     

威百亩对烟草漂浮苗干根中烟草花叶病毒的失活效果

为了评价威百亩用于烟草漂浮育苗旧苗盘残存物中烟草花叶病毒(Tobacco mosaic virus,TMV)的消毒效果,采用枯斑寄主和烟草品种K326接种方法,测定了威百亩熏蒸对烟草漂浮苗花叶病株干根中TMV的失活效果。结果表明,32.7%威百亩水剂16.7g/L溶液浸湿后熏蒸2～7d,对病苗干根中TMV的枯斑抑制率为84.0%～100%,对病苗干根中TMV的失活效果高,但有时不能完全失活。三抗体夹心法和试纸条检测结果表明,威百亩熏蒸8h～7d后,不能有效破坏病苗干根中TMV抗原。威百亩可用于无烟草花叶病毒病发病史的旧苗盘和漂浮育苗棚群场地、池膜消毒。     

宁南霉素、病毒A、娃儿藤碱对烟草花叶病毒的室内毒力活性测定

采用半叶法测定了宁南霉素、病毒A、娃儿藤碱对TMV的离体、活体的保护、治疗和钝化作用。试验结果表明,宁南霉素的钝化、保护效果和离体治疗效果较好,抑制率分别为93．24％、67．23％、74．78％,明显优于其他植物病毒抑制剂。     

Pharmacological Assessment of the Medicinal Potential of Acacia mearnsii De Wild.: Antimicrobial and Toxicity Activities

Acacia mearnsii De Wild. (Fabaceae) is a medicinal plant used in the treatment of microbial infections in South Africa without scientific validation of its bioactivity and toxicity. The antimicrobial activity of the crude acetone extract was evaluated by both agar diffusion and macrobroth dilution methods while its cytotoxicity effect was assessed with brine shrimp lethality assay. The study showed that both bacterial and fungal isolates were highly inhibited by the crude extract. The MIC values for the gram-positive bacteria (78.1-312.5) μg/mL, gram-negative bacteria (39.1-625) μg/mL and fungal isolates (625-5000) μg/mL differ significantly. The bacteria were more susceptible than the fungal strains tested. The antibiosis determination showed that the extract was more (75%) bactericidal than bacteriostatic (25%) and more fungicidal (66.67%) than fungistatic (33.33%). The cytotoxic activity of the extract was observed between 31.25 μg/mL and 500 μg/mL and the LC(50) value (112.36 μg/mL) indicates that the extract was nontoxic in the brine shrimp lethality assay (LC(50) > 100 μg/mL). These results support the use of A. mearnsii in traditional medicine for treatment of microbial infections. The extract exhibiting significant broad spectrum antimicrobial activity and nontoxic effects has potential to yield active antimicrobial compounds.     

牛心朴子草抑制植物病毒活性成分安托芬的室内和田间活性测定

首次发现广泛分布于我国西北旱沙荒漠地带的牛心朴子草提取物中生物碱部位对危害极大的烟草花叶病毒具有很高的抑制活性,经生物活性跟踪与色谱分离,结构鉴定确认主要活性成分是安托芬。安托芬在1mg/L质量浓度下对烟草花叶病毒的抑制率高达60%。活体植株抗病毒活性的毒力测定结果表明,安托芬对活体植株烟草花叶病毒和活体植株马铃薯Y病毒具有很高的抑制活性,如安托芬在9mg/L的质量浓度下对活体植株烟草花叶病毒和活体植株马铃薯Y病毒的抑制率分别高达75%和80%。田间小区试验结果表明,牛心朴子草的效果明显好于两个对照药剂宁南霉素和病毒A,对烟草的生长发育无不良影响。     

新型含吡啶环双酰胺衍生物的合成及生物活性

以吡啶羧酸和取代邻氨基苯甲酸为起始原料,设计并合成12个双杂环双酰胺类化合物,其结构经1HNMR、13CNMR、IR及元素分析确证。初步生物活性测试结果表明,在200、500μg/mL浓度下部分化合物对青枯病病原菌(Pseudomonas solanacearum)进行活性测试,结果表明所合成的化合物对青枯病病原菌有一定抑菌活性,其中N-(2-(6-乙氧基苯并噻唑-2-氨基甲酰基)-4-甲基苯基)-3-吡啶甲酰胺在500μg/mL浓度下对青枯病病原菌的抑菌活性为60%。     

新型生物杀菌剂新奥霉素防治烟草花叶病毒病的田间药效

新奥霉素是一种新型生物杀菌剂。对4%新奥霉素水剂防治烟草花叶病毒病进行了田间试验,结果表明,4%新奥霉素水剂对烟草花叶病毒病有很好的防治效果,第3次施药后7 d,900 mL/hm2、1350 mL/hm2和1800 mL/hm2处理对烟草花叶病毒病的防效分别为64.09%、72.19%和75.69%,其效果明显高于对照药剂20%吗胍.乙酸铜可湿性粉剂。     

新杀菌剂氟肟菌酯对几种作物病原菌的生物活性研究

采用含毒介质法和活体盆栽法对具有自主知识产权的新甲氧基丙烯酸酯类杀菌剂品种氟肟菌酯(试验代号HNPC-A4008)进行了生物活性研究。结果表明,氟肟菌酯对稻瘟病菌、水稻纹枯病菌、水稻恶苗病菌、小麦赤霉病菌、玉米小斑病菌和苹果轮纹病菌的菌丝生长具有明显的抑制作用,其EC50值分别为4.3652×10-3,8.985 6×10-2,1.752 6×10-1,8.830 0×10-1,2.261 5×10-1,3.031 8×10-1 g/mL,但对辣椒疫霉病菌菌丝生长的抑菌活性作用很弱,其EC50值为8.7039×101 g/mL。氟肟菌酯对黄瓜白粉病、小麦白粉病和水稻稻瘟病具有较好的保护和治疗作用,但内吸传导作用较弱。     

白头翁提取物抗TMV生物活性初探

[目的]探讨白头翁提取物的抗TMV活性,为从植物中开发抗病毒类生物农药提供依据.[方法]以烟草花叶病毒(TMV)为供试病毒,采用半叶枯斑法测定了白头翁提取物对TMV的生物活性.[结果]在供试质量浓度为10 g/L时,白头翁石油醚提取物对TMV具有明显的体外钝化作用,钝化0.5 h后,其抑制率达65.19％,对TMV的初侵染和增殖也有一定的抑制作用,处理24 h后,抑制率分别为46.67％和23.53％.     

天然化合物丁香酚抗烟草花叶病毒病作用机制初探

[目的]初步研究丁香酚对植物病毒病的作用机制.[方法]利用盆栽法测定了丁香酚对烟草花叶病毒病的预防和治疗效果;电镜法观察了丁香酚对病毒粒子的影响;体外混合法测定了丁香酚对烟草花叶病毒外壳蛋白体外聚合的影响.[结果]丁香酚对烟草花叶病毒病具有较好的预防和治疗效果;丁香酚与病毒混合处理后,病毒粒子有断裂现象;丁香酚对TMV外壳蛋白体外聚合有一定的抑制作用.[结论]丁香酚可以作为新型抗病毒剂用于防治作物病毒病.     

轮丝链霉菌(Streptomyces Ys.03)代谢产物的抗植物病毒活性及其分类鉴定

[目的]1株从土壤中分离得到的放线菌的抗植物病毒活性及其分类鉴定。[方法]室内对峙培养、枯斑和系统寄主的保护及治疗试验,菌株形态观察并结合培养特征、生理生化性状及16S rDNA序列测定。[结果]菌株Ys.03对蜡状芽孢杆菌有稳定的拮抗作用;发酵液与烟草花叶病毒(TMV)混合后接种枯斑和系统寄主,对TMV抑制率分别为95.01%和88.67%;接种前、后叶面分别喷施发酵液抑制率均较高;菌株孢子链轮生,16S rDNA测序与师岗轮丝链霉菌(Streptomyces mormookaensis)同源性达100%。[结论]菌株Ys.03代谢产物对TMV有显著的抑制作用,鉴定为链霉菌属轮生类群师岗轮丝链霉菌。     

Identification of Compounds in the Essential Oil of Nutmeg Seeds (Myristica fragrans Houtt.) That Inhibit Locomotor Activity in Mice

The present study was designed to evaluate the inhibitory effect of nutmeg (Myristica fragrans Houtt.) seed essential oil on the locomotor activity of mice in a wheel cage. Active compounds in the essential oil were identified by off-line solid phase extraction (SPE-C18) and GC/MS analysis. The essential oil was administered by inhalation at doses of 0.1, 0.3, and 0.5 mL/cage. The results showed that inhalation of nutmeg seed essential oil at a dose of 0.5 mL/cage decreased locomotion by 68.62%; and inhalation of 0.1 and 0.3 mL/cage inhibited locomotion by 62.81% and 65.33%, respectively. Generally, larger doses and longer administrations of nutmeg seed essential oil exhibited greater locomotor inhibition. Subsequently, the plasma concentrations of essential oil compounds were measured. The most concentrated compound in the plasma was myristicin. Half an hour after the addition of 1 mL/cage of nutmeg seed oil, the plasma concentration of myristicin was 3.7 μg/mL; one and two hours after the addition, the blood levels of myristicin were 5.2 μg/mL and 7.1 μg/mL, respectively. Other essential oil compounds identified in plasma were safrole (two-hour inhalation: 1.28 μg/mL), 4-terpineol (half-hour inhalation: 1.49 μg/mL, one-hour inhalation: 2.95 μg/mL, two-hour inhalation: 6.28 μg/mL) and fatty esters. The concentrations of the essential oil compounds in the blood plasma were relatively low (μg/mL or ppm). In conclusion, the volatile compounds of nutmeg seed essential oil identified in the blood plasma may correlate with the locomotor-inhibiting properties of the oil when administered by inhalation.     

氰烯菌酯(JS399-19)防治水稻恶苗病的研究

氰烯菌酯(JS399-19)是一种结构新颖、作用方式独特的高效杀菌剂。离体抑菌活性测定表明,JS399-19对水稻恶苗病多菌灵敏感菌株和抗性菌株均有相似活性,EC50为0.1612～0.3136μg/mL,EC95为1.5387～6.0455μg/mL;持效性测定表明,JS399-19在10d内对恶苗病菌的抑菌率是稳定的,抑菌率为77.9%～81.4%;种子安全性试验表明,以25%JS399-19SC1:1000倍浸种处理对水稻种子的发芽势有一定的影响,但不影响发芽率、出苗率及成苗率,1:2000、1:3000、1:4000倍浸种处理时水稻种子的发芽势、发芽率、出苗率成苗率等均与空白对照无明显差异;温室小区筛选试验表明,当25%JS399-19SC1:500、1:1000、1:2000、1:3000浸种处理时30d防效均为100%,1:4000倍时防效大于92%;初步应用技术研究表明,JS399-19防治水稻恶苗病,浸种处理剂量为1:3000～4000倍,当浸种温度为15～20℃时,浸种时间以48～72h为宜。本研究为氰烯菌酯防治水稻恶苗病的应用开发提供了依据。     

丙烯海松酸基双酰胺类化合物的合成及生物活性研究

经松香与丙烯酸的D-A加成反应制备丙烯酸改性松香,从中分离提纯得到丙烯海松酸。将丙烯海松酸转化为双酰氯,再与苯胺类化合物发生N-酰化反应,合成得到一系列新型丙烯海松酸基双酰胺类化合物,利用IR、1HNMR和13 CNMR表征了目标化合物的结构。初步生物活性测试表明,所合成的目标化合物在50μg/mL浓度下都对苹果轮纹病菌有一定的抑制活性,化合物丙烯海松酸基双对甲氧基苯酰胺在100μg/mL浓度下对油菜的胚根生长显示良好的抑制活性(达到A级活性水平)。     

Design,Synthesis and Antifungal/Nematicidal Activity of Novel 1,2,4-Oxadiazole Derivatives Containing Amide Fragments

Plant diseases that are caused by fungi and nematodes have become increasingly serious in recent years. However, there are few pesticide chemicals that can be used for the joint control of fungi and nematodes on the market. To solve this problem, a series of novel 1,2,4-oxadiazole derivatives containing amide fragments were designed and synthesized. Additionally, the bioassays revealed that the compound F15 demonstrated excellent antifungal activity against Sclerotinia sclerotiorum (S. sclerotiorum) in vitro, and the EC₅₀ value of that was 2.9 μg/mL, which is comparable with commonly used fungicides thifluzamide and fluopyram. Meanwhile, F15 demonstrated excellent curative and protective activity against S. sclerotiorum-infected cole in vivo. The scanning electron microscopy results showed that the hyphae of S. sclerotiorum treated with F15 became abnormally collapsed and shriveled, thereby inhibiting the growth of the hyphae. Furthermore, F15 exhibited favorable inhibition against the succinate dehydrogenase (SDH) of the S. sclerotiorum (IC₅₀ = 12.5 μg/mL), and the combination mode and binding ability between compound F15 and SDH were confirmed by molecular docking. In addition, compound F11 showed excellent nematicidal activity against Meloidogyne incognita at 200 μg/mL, the corrected mortality rate was 93.2%, which is higher than that of tioxazafen.     

1-(2-吡啶基)-3-甲基-4-三氟甲酰基-5-吡唑酮的合成及其与Fe~(3+)显色反应研究

合成了新型的酰基吡唑啉酮标题化合物,通过红外、核磁、质谱和元素分析对其进行表征,并研究了其与Fe~(3+)的显色反应。实验结果表明,该化合物对Fe~(3+)具有高选择的显色反应特性,Fe~(3+)质量浓度为0.18~1.8μg/mL,与相对吸光度呈良好的线性关系A=0.423ρ-0.020(μg/mL),相关性系数r=0.999 3,最低检出限为0.064μg/mL(n=11)。     

山胡椒抑制体内外α-糖苷酶活性研究

对山胡椒抑制酵母α-葡萄糖苷酶和大鼠小肠α-葡萄糖苷酶活性进行了研究。利用96微孔板法检测其α-葡萄糖苷酶抑制活性。结果表明,抑制酵母α-葡萄糖苷酶实验中,山胡椒石油醚部位(IC50=229.70μg/mL)、乙酸乙酯部位(IC50=259.10μg/mL)和正丁醇部位(IC50=165.80μg/mL)活性低于阳性对照Acarbose(IC50=1081.27μg/mL);抑制大鼠小肠α-葡萄糖苷酶实验中,仅有乙酸乙酯部位(IC50=418.17μg/mL)具有活性,阳性对照Acarbose未检测出其IC50。实验证明,山胡椒各提取部位具有较好抑制酵母α-葡萄糖苷酶活性,但只有乙酸乙酯部位具有良好的大鼠小肠α-葡萄糖苷酶抑制活性。     

The melanogenesis-inhibitory, anti-inflammatory, and chemopreventive effects of limonoids in n-hexane extract of Azadirachta indica A. Juss. (neem) seeds

Seventeen limonoids (tetranortriterpenoids 1-17) were isolated from the n-hexane extract of Azadirachta indica (neem) seeds. The previously unidentified compound 16 was established by spectroscopy to be 17-defurano-17-oxosalannin. The effects of six compounds, 6 and 11-15, on melanogenesis in B16 melanoma cells was evaluated; 2 compounds, salannin (13) and 3-deacetylsalannin (15), exhibited marked inhibitory effects (70-74% reduction of melanin content at 25 μg/mL) with only minor cytotoxicity (79-85% of cell viability). Eleven compounds, 2, 3, 5, 6, and 9-15, were evaluated for inhibitory activity against 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation (1.7 nmol/ear) in mice; all exhibited marked anti-inflammatory activity (ID(50) values 0.22-0.57 μmol/ear). In addition, compounds 6 and 11-16 exerted moderate inhibition (IC(50) values of 410-471 mol ratio/32 pmol TPA) of TPA-induced Epstein-Barr virus early antigen (EBV-EA) activation in Raji cells. The triacylglycerol fraction of the n-hexane extract contained oleic acid (50.2%) as the most predominant fatty acid constituent.     

N-(1,4-二取代吡唑-5-基)-1,2,3-噻二唑酰胺类化合物的合成与杀菌活性研究

设计合成了9个N-(1,4-取代吡唑-5-基)-1,2,3-噻二唑酰胺类化合物,测试了化合物对小麦赤霉病菌(Gibberella zeae)、辣椒枯萎病菌(Fusarium oxysporum)和苹果腐烂病菌(Cytospora mandshurica)的抑制活性。初步结果表明,目标化合物在50μg/mL浓度下对小麦赤霉病菌、辣椒枯萎病菌和苹果腐烂病菌有一定的抑制作用,其中化合物8j对小麦赤霉病菌的抑制率达到47.6%,接近对照药剂恶霉灵;化合物8d对苹果腐烂病菌的抑制率达到56.8%,与对照药剂恶霉灵相当,具有进一步研究的价值。     

大孔树脂吸附法吸附分离黄酮的研究

研究了D101、LD601、LS-303B、LX-28、LX-38型大孔树脂对黄酮的吸附及分离性能。结果表明,LD601型大孔树脂对黄酮的吸附效果较好,pH 2～4的盐酸溶液中,静态吸附量为5 849.312μg/g,对流速2 mL/min黄酮溶液的吸附率可达96.27%,负载1 500μg黄酮的LD601树脂,用40%乙醇50 mL以3 mL/min流速进行解吸,解吸率可达97.51%。