茄科植物糖苷生物碱抗肿瘤活性及其构效关系研究进展

糖苷生物碱是一种广泛存在于茄科植物中的天然产物,因其具有重要的生物活性而受到人们的重视.糖苷生物碱中糖苷配基与糖部分的不同组合使其具有不的化学结构,而化学结构决定了其生物活性,目前研究最多的是其显著的抗肿瘤活性.然而迄今为止,该类化合物的确切抗肿瘤药理机制和其构效关系尚未得到阐明.因此,本文从化学结构、抗肿瘤活性和构效...     

五种新疆植物的抗真菌活性

对采自新疆的黄花蒿(Artemisia annua)、北艾(Artemisia vulgaris)、梭梭(Halaxylon ammodendron)、盐爪爪(Kalidium foliatum)和多枝柽柳(Tamarix ramosissima)抗植物病原真菌的活性进行了研究,植物病原真菌包括番茄灰霉病菌(Botrytis cinerea)、棉花枯萎病菌(Fusarium axysporum f.sp.vasinfectum)、稻瘟病菌(Magnaporthe grisea)、烟草黑胫病菌(Phytophthora parasitica var.nicotianae)和瓜果腐霉(Pythium aphani-dermatum),其中黄花蒿对真菌菌丝生长、多枝柽柳对稻瘟病菌孢子萌发表现出强的抑制活性。本研究为植物病害防治和新疆植物资源的开发和利用提供了依据。     

几种药用植物精油的抗真菌活性研究

研究了作用浓度为0：7-4．0μL/mL的南方药用植物香茅（Cymbopogon citratus）、广藿香（Pogostemon cablin（Blanco）Benth）、大叶桉（Eucalyptus robusta Smith）和蛇床（Cnidium monnier（L.）Cusson）的精油对6种植物病原真菌的抑制活性。结果表明,大叶桉、广藿香和香茅精油对串珠镰刀病菌（Fussarium moniliforme）、玉米弯孢霉菌（Curvjlaria lunata）对多种供试植物病原真菌的生长有明显抑制活性,其中,香茅精油在浓度为3．3μL/mL时,能完全抑制大部分供试真菌的生长。但不同精油对于各病原真菌的抑制率有一定差异。本研究为复合植物精油抗真菌农药的开发提供依据。     

菊状千里光化学成分及抗真菌活性研究

研究菊状千里光的化学成分,为进一步探讨其药理作用提供理论依据.菊状千里光乙醇提取物经大孔树脂初步分离后,采用凝胶色谱、硅胶色谱、MCI等方法分离纯化化合物,通过化合物的理化性质与波谱数据分析鉴定其结构.使用MTT法测定分离得到的两个生物碱对正常肝细胞L-02的毒性,并通过琼脂平板打孔法对菊状千里光中得到的部分化合物进行...     

三种药用植物内生真菌抗真菌活性的研究

从雪上一枝蒿(Aconitumbrachypodum)、刺五加(Acanthopanaxsenticosus)和大血藤(Sargentodoxacuneata)分离获得的162株内生真菌进行抗真菌活性检测,结果具有抗菌活性菌株有74株,雪上一枝蒿15株,刺五加23株,大血藤36株,分别占3种植物各自内生真菌的44.12%,48.94%和44.44%。将具有抗菌活性的菌株进行分类鉴定,分属于6目、7科、23属。     

小桐子内生真菌及其抗真菌活性研究

从药用植物小桐子的根和茎中分离到内生真菌57株,经鉴定,它们分属于15个不同的分类单元。其中拟盘多毛孢为优势属,其次为拟茎点霉属和茎点霉属。用杨桃炭疽菌,香蕉疫霉和镰刀菌作指示菌对这些内生真菌的抗真菌活性进行检测,结果表明,有2株菌对杨桃炭疽菌具有抑菌活性。     

马铃薯糖苷生物碱对人血胆碱酯酶的抑制

马铃薯糖苷生物碱是一类有异味有毒性的含氨甾族化合物,其致毒机理与有机磷杀虫剂相似,表现出对人体内胆碱酯酶活性的抑制,使胆碱能神经兴奋增强,引起一系列中毒症状。从块茎萌发芽中提取的总糖苷生物碱的毒性较高,对人血胆碱酯酶的体外抑制率为６３．０８％,单个糖苷生物碱（α茄碱和α卡茄碱）的毒性较低,抑制率分别为５２．０８％和４１．１５％,总糖苷生物碱的水解产物糖苷配基基本无毒性,抑制率仅为１１．３６％。     

海洋微生物几丁质酶分离纯化及其抗真菌活性

以实验室筛选的海洋产几丁质酶短芽胞杆菌属（Bacillus brevis sp．）菌株Bspl,经往复式摇床振荡培养96h后,发酵液先后采取了75％的硫酸铵盐析、透析、几丁质亲和层析、SDS—PAGE等方法对几丁质粗酶液进行分离纯化和鉴定。几丁质亲和层析一步纯化后,经过SDS—PAGE电泳测定该酶的分子量为23ku,其比活力为86．65．纯化倍数为1．707、产率为32．1％。纯化的几丁质酶能抑制病原真菌的生长,对病原真菌的拮抗作用具有广谱性。同时研究了几丁质酶的稳定性,以胶态几丁质为底物,分离的几丁质酶在pH7．5,55．0℃左右具有最大酶活性;Zn^2＋、Cu^2＋和Hg^2＋能强烈抑制几丁质酶活性;Ni^＋和EDTA抑制20％-40％;然而5mmol／LCo^2＋可以使几丁质酶活性提高1．4倍;Mg^2＋、Ca^2＋等也能使酶活性增加。     

中药提取物对酵母菌抗真菌活性研究

目的探讨6味中药2种方法提取成分对酵母菌的抑菌和杀菌作用。方法采用药基琼脂稀释法,测定6味中药水提和醇提成分对白念珠菌和糠秕马拉色菌的MIC和MFC。结果对白念珠菌：水提黄连、醇提黄柏、醇提土槿皮MIC范围分别为0．625—1．25mg／mL、0．625～1．25mg/mL、0．313—0．625mg／mL;均值均为0．625mg／mL;对糠秕马拉色菌：水提和醇提黄连MIC范围分别为0．625～1．25mg／mL和1．25mg／mL,均值均为1．25mg／mL。对白念珠菌：醇提土槿皮MFC范围0．625～2．5mg/mL,均值0．625rag／mL。结论水提黄连、醇提黄柏和土槿皮对白念珠菌有较强抑菌作用,其中醇提土槿皮有较强杀菌作用。水提和醇提黄连对糠秕马拉色菌有较强抑菌作用。     

家蝇幼虫血淋巴中抗真菌肽的诱导方法比较及抗真菌活性

以未诱导组作为空白对照研究比较真菌诱导、超声诱导和热诱导家蝇Musca domestica 幼虫血淋巴初提液的抗真菌肽效果,比较各种诱导方法诱导后的幼虫存活率;用凝胶层析法和高效液相分离纯化热诱导家蝇3龄幼虫抗真菌肽,检测其抗白假丝酵母菌Candida albicans和新生隐球菌Cryptococcus neoformans活性;SDS-PAGE分析抗真菌肽的蛋白分子量范围。结果表明：3种诱导方法诱导后家蝇幼虫均产生具有明显抗真菌作用的抗真菌肽,其初提液抑菌圈大小没有明显差别;真菌诱导组和热诱导组幼虫存活率低于对照组,而超声诱导组与对照组相比则无明显差别。经分离纯化后,抗真菌肽仍具有较好的抗真菌活性;SDS-PAGE分析表明该抗真菌肽有效成分的蛋白分子量在14.4 kD以下。结果提示热诱导家蝇幼虫产生抗真菌肽是一种方便、有效的诱导方式。     

Effectiveness of plant extracts to control purple blotch and Stemphylium blight diseases of onion (Allium cepa L.) in Assiut,Egypt

The present investigation aimed to isolate the causative agents of onion purple blotch and Stemphylium blight diseases and evaluate the efficacy of certain plant extracts against the two identified pathogens, in vitro and under greenhouse condition. Fourteen isolates of S. vesicarium and two isolates of Alternaria porri were tested for pathogenicity. The results indicated that all isolates were able to produce the symptoms of Stemphylium blight and onion purple blotch diseases with different degrees of severity ranging from 10.42 to 81.25%. A. porri No. 6022 caused the highest disease severity (81.25%), while S. vesicarium No. 6003 was the best one out of the tested 14 isolates (37.5%). Antifungal activity of some aqueous plant extracts (Azadirachta indica, Cydonia oblonga, Datura stramonium, Eucalyptus globulus, Foeniculum vulgare, Ocimum basilicum, Rosmarinus officinalis and Salix mucronata) was assayed in vitro by dry weight technique. The data indicated that there were significant differences between these extracts in their effect on fungal growth of A. porri and S. vesicarium and the best were A. indica and D. stramonium. Under greenhouse conditions, application of the aqueous extract of A. indica either before or after 48?h A. porri inoculation produced the highest reduction in disease severity comprising 70 and 74.7%, respectively. On the other hand, the highest percentage of disease reduction before and after 48?h S. vesicarium inoculation was produced by Ridomil gold plus reached to 84.4 and 95.8% respectively, followed by the aqueous extract of A. indica (74.1 and 89.7, respectively). According to our results, it can be concluded that plant extracts of A. indica and D. stramonium can be used for the biocontrol of purple blotch and Stemphylium blight diseases instead of fungicides to minimise the risks and hazards of using toxic fungicides.     

The male gametophyte of Bonnemaisonia hamifera Hariot in Norway

The male gametophyte of Bonnemaisonia hamifera Hariot is recorded for the first time in Norway. The plants were collected in the Bj?r?ya archipelago situated between 10° 46′-10° 52′ E and 64° 35·5′-64° 37′ N. Numerous large antheridia were present on the plants which were attached to the rock at a depth of 150–200 cm below E.L.W.S.     

白菜黑斑病菌三个种菌株基本培养条件比较

选用来自国内外的白菜黑斑病菌三个种Alternaria brassicicola,A. brassicae和A. japonica为研究材料,以生长速率为评价指标,对其适宜生长温度、pH值、光照、培养基和菌落特征等基本培养条件和性状进行了对比研究。结果表明,三个种的病菌最适生长温度均在20℃～25℃,变化幅度较小,但A. brassicicola 和A. japonica菌丝体生长温度范围和已有文献报道相比提高了5℃;A. brassicae中国菌株菌丝体生长的pH值范围为4~8,其它所有供试菌株生长的pH值为3~11;24h光照、12h光暗交替和24h黑暗对国内外A. brassicicola菌株生长速率影响均不大,而A. brassicae在24h光照和12h光暗交替下的生长速率比24h黑暗处理的显著增大,24h光照和24h黑暗比12h光暗交替更适合A. japonica生长;PDA是白菜黑斑病菌营养生长的最适培养基,SNA除了适合其生长外,还对供试三个种的病菌生长有选择性;菌落直径及颜色可以作为区分三个种的参考指标。供试的白菜黑斑病菌三个种在基本培养条件方面存在种水平上的差异。     

A Novel Isoindoline,Porritoxin Sulfonic Acid,from Alternaria porri and the Structure-phytotoxicity Correlation of Its Related Compounds

Novel zinniol-related compound 3, named porritoxin sulfonic acid, with an isoindoline skeleton was isolated from the culture liquid of Alternaria porri. The structure was determined to be 2-(2″-sulfoethyl)-4-methoxy-5-methyl-6-(3′-methyl-2′-butenyloxy)-2,3-dihydro-1H-isoindol-1-one. The phytotoxic activities of three isoindolines (1-3) were evaluated in a seedling-growth assay against stone leek and lettuce.     

Production of phytotoxic spore germination liquids by Alternaria brassicae and A. brassicicola and their effect on species of the family Brassicaceae

Experiments assessed the susceptibility of Brassica spp. and non-Brassica spp. in the family Brassicaceae to infection by Alternaria brassicae and A. brassicicola, and determined the sensitivity of the host species to spore germination liquids (SGLs) produced by the pathogens on B. napus leaves. There was a wide range of sensitivity to the pathogens. Brassica spp. were generally more susceptible, and some non-Brassica spp. (Barbarea vulgaris and Capsella bursa-pastoris) were immune to A. brassicicola. Measurable damage was caused by SGLs but with significant variation between host species. Non-hosts and weak hosts also showed necrosis. It was concluded that, in the case of both pathogens, the toxic factors in these SGLs were host-selective. Selectivity in toxin production was also demonstrated in relation to the host surface or growing medium in which spores germinated. A substantial amount of toxin was produced on all Brassicaceae tested but not on unrelated species (Triticum aestivum, Pisum sativum and Lycopersicon esculentum). Neither pathogen produced measurable amounts of toxin when cultured in Czapek (Dox) broth.     

Growth inhibition effect of pyroligneous acid on pathogenic fungus,<Emphasis Type="Italic">Alternaria mali</Emphasis>, the agent of Alternaria blotch of apple

We investigated the growth inhibition effect of pyroligneous acid on the pathogenic fungus,Alternaria mali, which is known to be the agent of Alternaria blotch of apple plants. Chemical control ofA. mali could be achieved through the use of agrochemical fungicides, while the substitute for agrochemical control is gradually increasing. It was observed that pyroligneous acid exhibited antifungal activity against some plant pathogenic fungi. More specifically, the growth ofA. mali was completely inhibited in pyroligneous acid at a dilution of 1∶32. When its antifungal activity was compared to that of polyoxin B, which is used for the chemical control of Alternaria blotch of apple, it was observed that the antifungal activity of pyroligneous acid diluted at 1∶32 corresponded to 2.0 mg/mL of polyoxin B. Consequently, it is concluded that the diluted pyroligneous acid can substitute for polyoxin B, thereby reducing the use of the agrochemical for the control of Alternaria blotch of apple.