β-氨基丁酸诱导黄瓜抗黄瓜炭疽病筛选体系的构建

为了给新型植物诱导抗病激活剂的创制提供基本的筛选平台，测定β-氨基丁酸对病原真菌的离体抑菌活性，探索了β-氨基丁酸诱导黄瓜植株对黄瓜炭疽病抗性的活体筛选方法，并探索了经β-氨基丁酸诱导和挑战接种前后黄瓜植株体内苯丙氨酸解氨酶（PAL）、多酚氧化酶（PPO）、过氧化物酶（POD）和超氧化物歧化酶（SOD）活性的变化。结果表明，β-氨基丁酸无离体的抑菌活性，20mmol／L的β-氨基丁酸可以诱导黄瓜产生70％以上的抗病效果。生理生化测定结果表明，经BABA诱导处理黄瓜第一叶真叶后，提高新生真叶的PAL和POD的活性；电泳分析发现，β-氨基丁酸诱导接种后的黄瓜叶片产生了病程相关蛋白（PRP）。根据研究结果，提出了植物诱导抗病激活剂筛选的完整体系。     

植物内生真菌抑制细菌活性菌株的筛选

室内以离体方法测试了供试植物内生真菌样品的丙酮提取物对枯草芽孢杆菌、金黄色葡萄球菌、大肠杆菌3种病原细菌抑菌活性，筛选出了对供试细菌有很好离体抑菌效果的植物内生真菌样品，2种是从银杏上分离的内生真菌，1种为扶芳藤上分离的内生真菌。     

根围细菌次生代谢物的生物活性筛选

从全国7个地区采集的植物根围土壤样品中分离得到1700余株植物根嗣细菌.采用室内离体筛选的试验方法,以5种植物病原细菌作为靶标,筛选研究得到有生物活性的菌株840株.其中10%的菌株对5种植物病原细菌都具有拮抗活性,其余菌株则仅对1种或几种病原细菌具有拈抗活性.从中进一步筛选得到对小麦白粉病也具有防治效果的菌株,其防治效果最高可达60%.将最终获得的同时对病原细菌有拮抗效果和真菌病害有防治效果的根围细菌作为以后深入研究的对象.     

杀菌剂生物筛选离体活体兼顾的重要性

新合成的以金核霉素结构改造为主的数十种化合物,经多种病原菌的离体抑菌活性测定和盆栽防治效果测定,谈谈在杀菌剂生物筛选中采用离体活体测定相兼顾的重要性.     

壳聚糖希夫碱的合成及其抗菌活性探究

文章简述了羧甲基壳聚糖水杨醛希夫碱(CTC-SSB)的制备方法。通过FI-IR对其结构进行了表征。以壳寡糖(COS)和壳寡糖水杨醛(COS-SSB)希夫碱为参照,测得其对多种病原菌和作物病菌的抗病激活性。离体活性测定,结果显示浓度为100mg·L-1时,对水稻纹枯病的诱导抗病效果高达91.4%。而活体盆栽活性测定,浓度分别为250mg·L-1和500mg·L-1时,对水稻稻瘟病的诱导抗病活性达到63.8%,77.8%,均高于COS(46.9%),显示羧甲基壳聚糖衍生物有一定的抗病激活性,具有药物缓释效果。     

左旋松油醇对植物病原菌的抑菌活性研究

在室内测定了左旋松油醇对4种植物病原细菌和14种植物病原真菌的抑菌活性.结果表明,左旋松油醇对供试的植物病原菌均有一定的抑制作用.在参试的植物病原细菌中,3.0 mg·mL-1浓度的左旋松油醇对番茄青枯病菌的抑制作用较强,抑菌圈的直径为13.3 mm.而在参试的植物病原真菌中,左旋松油醇对玉米大斑病菌、水稻纹枯病菌及芥菜黑斑病菌有较好的抑菌效果,EC50分别为0.1053 mg·mL-1、0.1127 mg·mL-1和0.1400mg·mL-1.     

海洋微生物源农用抗生活性物质的筛选

对134株海洋微生物(其中49株海洋放线菌、54株海洋细菌、31株海洋真菌)进行农用抗生活性物质筛选,分别测定其发酵上清液和菌丝体浸提液的活体抗植物病源真菌、杀虫、除草活性,发现共有77株菌株具有农用抗生活性,其中7株海洋放线菌的代谢产物的活性较高:3株对植物病原真菌具有较好抑制活性的海洋放线菌代号为Y12–26、P10–16、JWH–09;两株具有较高杀蚜虫活性的海洋放线菌是P10–23、P12–21;两株除草活性较好的海洋放线菌是YY01–17和HH1901–45。     

细菌抑制剂离体生物活性试验

[目的]为明确化学药剂对病原细菌的离体抑菌活性,进而为田间病害防治提供优秀的候选药剂。[方法]将黄瓜细菌性角斑病菌(Pseudomonas syringae pv.lachrymans)等常见病原细菌作为防治靶标,利用带菌平板法,对药剂的离体抑菌活性进行对比研究。[结果]不同的药剂对病原细菌的离体抑菌活性差异很大,链霉素、土霉素等药剂对多种病原细菌具有较高的离体抑菌活性。[结论]试验采用带菌平板法,能够对药剂的离体抑菌活性进行准确检测。     

离体试验与活体检测相结合的杀细菌剂筛选

[目的]为了提高筛选效率,将离体与活体筛选方法相结合,开展杀细菌剂筛选研究。[方法]首先通过离体高通量筛选和最小抑菌浓度检测的方法对化合物进行筛选,最后通过活体试验来进一步确定化合物的抑菌活性。[结果]采用高通量筛选和最小抑菌浓度检测等离体方法,筛选获得了具有抑菌活性的化合物,这些化合物在最终的活体试验中,仅有部分化合物表现出活体抑菌活性。[结论]离体高通量与活体试验相结合的筛选方法,能够快速准确的对化合物开展杀细菌活性筛选研究。     

新型杀菌剂苯并咪唑喹啉铜对辣椒疫霉的抑菌活性

[目的]苯并咪唑喹啉铜是多菌灵和喹啉铜螯合而成的新杀菌剂.为明确其应用价值,测定了它对辣椒疫霉的抑菌效果.[方法]分别用生物测定法和盆栽法测定了药剂对辣椒疫霉各发育阶段的离体活性以及活体药效.[结果]苯并咪唑喹啉铜对游动孢子囊形成、萌发以及游动孢子休止孢萌发均有很好的抑制效果,EC50值在0.01～0.2 mg/L之间;活体试验中,200 mg/L苯并咪唑喹啉铜防效达73.46％.[结论]该药剂还具有兼治多种真菌病害的潜力,对合成新农药和治理抗药性风险具有很大价值.     

Extraction,Chemical Composition,and Antifungal Activity of Essential Oil of Bitter Almond

The essential oil from the powder residual of dried bitter almond, a novel and environmentally-friendly fungicide, was successfully extracted in a 0.7% yield by hydro-distillation under optimized conditions. The chemical composition of bitter almond essential oil (BAEO) was analyzed by gas chromatography–mass spectrometry (GC–MS). Twenty-one different components representing 99.90% of the total essential oil were identified, of which benzaldehyde (62.52%), benzoic acid (14.80%), and hexadecane (3.97%) were the most abundant components. Furthermore, the in vitro and in vivo antifungal activities of BAEO against common plant pathogenic fungi were evaluated by the mycelium linear growth rate method and pot test, respectively. It was documented that 1 mg/mL of BAEO could variously inhibit all tested pathogenic fungi with the inhibition rates of 44.8%~100%. Among the tested 19 strains of fungi, the median effective concentration (EC₅₀) values of BAEO against Alternaria brassicae and Alternaria solani were only 50.2 and 103.2 μg/mL, respectively, which were higher than those of other fungi. The in vivo antifungal activity of BAEO against Gloeosporium orbiculare was much higher than Blumeria graminis. The protective efficacy for the former was up to 98.07% at 10 mg/mL and the treatment efficacy was 93.41% at 12 mg/mL. The above results indicated that BAEO has the great potential to be developed as a botanical and agricultural fungicide.     

重组人干扰素α2b喷雾剂的研制

目的重组人干扰素α2b(以下简称为rIFNα2b)喷雾剂的试制及临床前实验。方法将重组人干扰素α2b原液进行稀释,调整pH和渗透压,加入适宜稳定剂,除菌过滤后分装于带有定量喷雾装置的棕色玻璃瓶。对配制好的制品分别进行理化和生物学试验、稳定性试验、鼻腔局部刺激性试验、急性毒性试验、长期毒性试验和动物体内抗病毒试验等。结果连续3批制品经检定各项指标均合格,2～8℃保存24个月后生物学活性无明显下降,使用安全,无不良反应。其他各项检定指标均符合现行《中国药典》的要求。结论研制的rIFNα2b喷雾剂安全、稳定,具有一定的抗病毒作用和潜在的临床应用价值。     

In Vivo Structure–Activity Relationship Studies Support Allosteric Targeting of a Dual Specificity Phosphatase

Dual specificity phosphatase 6 (DUSP6) functions as a feedback attenuator of fibroblast growth factor signaling during development. In vitro high throughput chemical screening attempts to discover DUSP6 inhibitors have yielded limited success. However, in vivo whole‐organism screens of zebrafish identified compound 1 (BCI) as an allosteric inhibitor of DUSP6. Here we designed and synthesized a panel of analogues to define the structure–activity relationship (SAR) of DUSP6 inhibition. In vivo high‐content analysis in transgenic zebrafish, coupled with cell‐based chemical complementation assays, identified structural features of the pharmacophore of 1 that were essential for biological activity. In vitro assays of DUSP hyperactivation corroborated the results from in vivo and cellular SAR. The results reinforce the notion that DUSPs are druggable through allosteric mechanisms and illustrate the utility of zebrafish as a model organism for in vivo SAR analyses.     

重组小纤溶酶的制备及其生物学活性

目的制备重组小纤溶酶,并检测其生物学活性。方法将重组质粒pET11a-miniPlg转化E.coli BL21(DE3),进行诱导表达。收获菌体,提取包涵体,经复性、层析纯化、尿激酶激活,制备小纤溶酶。进行初步理化鉴定后,采用生色底物法测定其体外活性,采用动物模型进行体内溶栓试验,并与重组组织型纤溶酶原激活剂(rt-PA)进行比较。结果小纤溶酶的表达量约占菌体总蛋白的30%～35%,纯化收率约为15%,得率为4.93mg/g菌体湿重,相对分子质量为38527,N-、C-端氨基酸序列与理论值一致。制备的小纤溶酶比活性为115IU/mg,动物模型溶栓试验中表现出良好的溶栓效果,对纤溶系统和凝血系统影响轻微。结论所制备的重组小纤溶酶具有良好的生物学活性,溶栓效果及安全性均优于rt-PA。     

Synthesis,PASS-Predication and in Vitro Antimicrobial Activity of Benzyl 4-O-benzoyl-α-l-rhamnopyranoside Derivatives

Benzyl α-l-rhamnopyranoside 4, obtained by both conventional and microwave assisted glycosidation techniques, was subjected to 2,3-O-isopropylidene protection to yield compound 5 which on benzoylation and subsequent deprotection of isopropylidene group gave the desired 4-O-benzoylrhamnopyranoside 7 in reasonable yield. Di-O-acetyl derivative of benzoate 7 was prepared to get newer rhamnopyranoside. The structure activity relationship (SAR) of the designed compounds was performed along with the prediction of activity spectra for substances (PASS) training set. Experimental studies based on antimicrobial activities verified the predictions obtained by the PASS software. Protected rhamnopyranosides 5 and 6 exhibited slight distortion from regular ¹C₄ conformation, probably due to the fusion of pyranose and isopropylidene ring. Synthesized rhamnopyranosides 4–8 were employed as test chemicals for in vitro antimicrobial evaluation against eight human pathogenic bacteria and two fungi. Antimicrobial and SAR study showed that the rhamnopyranosides were prone against fungal organisms as compared to that of the bacterial pathogens. Interestingly, PASS prediction of the rhamnopyranoside derivatives 4–8 were 0.49 < P_a < 0.60 (where P_a is probability ‘to be active’) as antibacterial and 0.65 < P_a < 0.73 as antifungal activities, which showed significant agreement with experimental data, suggesting rhamnopyranoside derivatives 4–8 were more active against pathogenic fungi as compared to human pathogenic bacteria thus, there is a more than 50% chance that the rhamnopyranoside derivative structures 4–8 have not been reported with antimicrobial activity, making it a possible valuable lead compound.     

猪源枯草芽孢杆菌喷雾干燥工艺的优化

目的优化猪源枯草芽孢杆菌喷雾干燥工艺,提高菌体喷雾干燥后的存活率。方法应用SAS V 8.0统计分析软件中的二次正交旋转组合设计方案进行试验设计,分析各因素对Y值的效应关系;应用优化的喷雾干燥工艺进行3次重复喷雾干燥试验,验证预测结果的准确性;并检测芽孢率对菌体喷雾干燥存活率的影响。结果优化的喷雾干燥工艺中各条件的最佳参数为:出口温度90℃,入口温度150℃,保护剂浓度20%,入料速度1 200 ml/h;应用优化的喷雾干燥工艺进行3次重复喷雾干燥试验,菌体平均存活率为75.7%,与预测值(77%)基本相符;芽孢率对菌体喷雾干燥存活率影响较大。结论优化了猪源枯草芽孢杆菌的喷雾干燥工艺,为其工业化生产奠定了基础。     

Multi-Omics Revealed Molecular Mechanisms Underlying Guard Cell Systemic Acquired Resistance

Systemic Acquired Resistance (SAR) improves immunity of plant systemic tissue after local exposure to a pathogen. Guard cells that form stomatal pores on leaf surfaces recognize bacterial pathogens via pattern recognition receptors, such as Flagellin Sensitive 2 (FLS2). However, how SAR affects stomatal immunity is not known. In this study, we aim to reveal molecular mechanisms underlying the guard cell response to SAR using multi-omics of proteins, metabolites and lipids. Arabidopsis plants previously exposed to pathogenic bacteria Pseudomonas syringae pv. tomato DC3000 (Pst) exhibit an altered stomatal response compared to control plants when they are later exposed to the bacteria. Reduced stomatal apertures of SAR primed plants lead to decreased number of bacteria in leaves. Multi-omics has revealed molecular components of SAR response specific to guard cells functions, including potential roles of reactive oxygen species (ROS) and fatty acid signaling. Our results show an increase in palmitic acid and its derivative in the primed guard cells. Palmitic acid may play a role as an activator of FLS2, which initiates stomatal immune response. Improved understanding of how SAR signals affect stomatal immunity can aid biotechnology and marker-based breeding of crops for enhanced disease resistance.     

用科学发展观正确认识腐植酸类环保农药

用科学发展观正确认识腐植酸类环保农药。腐植酸作为农作物生长调控的天然有机物质,环保、经济、安全,与农药结合的空间很大。腐植酸作为植物生长调节剂已属农药之列;腐植酸因其具有的生物活性,可与各类农药结合研制具有环保特色的新型农药;腐植酸作农药助剂、填充剂,将赋予农药新的活力;腐植酸类环保农药具有与农业可持续发展相适应的优越性。     

The Antifungal Mechanism of Isoxanthohumol from Humulus lupulus Linn.

Humulus lupulus Linn. is a traditional medicinal and edible plant with several biological properties. The aims of this work were: (1) to evaluate the in vitro antifungal activity of H. lupulus ethanolic extract; (2) to study the in vitro and in vivo antifungal activity of isoxanthohumol, an isoprene flavonoid from H. lupulus, against Botrytis cinerea; and (3) to explore the antifungal mechanism of isoxanthohumol on B. cinerea. The present data revealed that the ethanolic extract of H. lupulus exhibited moderate antifungal activity against the five tested phytopathogenic fungi in vitro, and isoxanthohumol showed highly significant antifungal activity against B. cinerea, with an EC₅₀ value of 4.32 µg/mL. Meanwhile, it exhibited moderate to excellent protective and curative efficacies in vivo. The results of morphologic observation, RNA-seq, and physiological indicators revealed that the antifungal mechanism of isoxanthohumol is mainly related to metabolism; it affected the carbohydrate metabolic process, destroyed the tricarboxylic acid (TCA) cycle, and hindered the generation of ATP by inhibiting respiration. Further studies indicated that isoxanthohumol caused membrane lipid peroxidation, thus accelerating the death of B. cinerea. This study demonstrates that isoxanthohumol can be used as a potential botanical fungicide for the management of phytopathogenic fungi.     

以天然产物为先导化合物开发的农药品种(Ⅰ)--杀菌剂

研究天然产物的重点不是直接利用它，而是以其为先导化舍物开发活性更优的天然产物替代品。只有如此，才能保护有限的资源，更好的为人类持续发展服务。在农药创制研究中以天然产物为先导化合物进行研究、开发新农药品种的方法仍将是一种有效的方法；因为以具有活性的天然产物为先导化合物不仅可以更快、更经济的发现活性更优的类似物，而且因其内在的性能是产品更易符合环境保护与持续发展之需要。本文概述了以天然产物为先导化合物进行的新农药创制研究以及开发的农药品种，其中杀菌剂包括乙蒜素、稻瘟灵、恶霉灵、肉桂酸衍生物、吡咯类化合物、甲氧基丙烯酸酯类等。旨在吸取他人成功经验，利用其研究之成果研制我们自己的新农药品种。