放线菌SPRI0518次级代谢产物的分离提纯及结构鉴定

从放线菌SPRI0518次级代谢产物中分离得到两组具有生物活性的化合物,分别命名为SPRI0518-Ⅰ和SPRI0518-Ⅱ.经过红外光谱、质谱以及核磁共振等分析,确定SPRI0518-Ⅰ为邻苯二甲酸二丁酯,其生理活性已经得到证实;确定SPRI0518-Ⅱ为-组同系物,分子式分别为C36H64O4、C37H68O4,具有除草活性.     

长川霉素的研究

从一株链霉菌的培养基中，经溶剂萃取、硅胶柱层析、TLC、HPLC等方法，分离得到SPRI－2098纯样品，根据其物化性质以及各类图谱分析得知：SPRI－2098和Ascomycin为同一个化合物（我们命名为长川霉素），该化合物具有很强的抗真菌活性，对许多植物病害真菌有很好的防治效果。     

紫穗槐种子杀菌活性成分的提取、分离与鉴定

[目的]研究紫穗槐种子中杀菌活性成分。[方法]利用硅胶柱层析,高速逆流色谱法等方法对紫穗槐种子的乙酸乙酯提取物进行分离,并对提取化合物进行杀菌活性测定。[结果]从紫穗槐种子的乙酸乙酯提取物中分离得到7个化合物,分别为5-羟基-7,4’-二甲氧基异黄酮、2’-羟基-4,4’-二甲氧基查耳酮、7,4’-二甲氧基异黄酮、鱼藤酮、11-羟基灰叶素、异灰毛豆酚、异灰叶素。其中鱼藤酮、11-羟基灰叶素、异灰毛豆酚、异灰叶素对黄瓜霜霉活性较好。[结论]紫穗槐中杀菌活性成分主要是鱼藤酮类化合物。     

新报道的一些具有农药活性的化合物

在全球的粮食生产中,农药发挥着很大的作用。然而农药应用也带来了一系列问题,如抗性的产生,对环境的影响和人畜的毒害作用,急需人们开发新颖的、安全、低毒农药。以天然物质为农药,或以天然化合物为农药先导物,是目前农药开发的重要途径。介绍了一些具杀线虫活性的天然酯和其类似物,具拒食和杀虫活性的萘酚衍生物以及从刺苞菜蓟分离得到的具有除草活性的物质,具杀螨和杀虫活性的喹啉类似物,具杀菌活性脂肽,除草活性物质holadysenterine和新类别除草活性物质环戊-4-烯-1,3-二酮物。     

茜草中杀虫活性物质的分离及结构鉴定

在对茜草杀虫活性研究的基础上,通过杀虫活性跟踪分析和柱层析分离,从茜草石油醚萃取物中分离得到一种杀虫活性成分,经理化数据测试及UV、IR、MS、NMR等波谱分析及X射线单晶衍射分析,确定了该成分的结构,为一新的杀虫活性物质.     

2-烷氨基-3-对氟苯基-5-甲基-6-(1H-1,2,4-三唑-1-基)-噻吩并[2,3-d]嘧啶-4(3H)-酮衍生物的合成及其杀菌活性

已见含氟类有机物具有杀菌能力的报道,将氟元素引入到噻吩并嘧啶酮的衍生物之中,考查其杀菌活性。通过Gewald反应生成噻吩,产物同PPh3、C2Cl6、Et3N作用得到膦亚胺,再用对氟苯基异氰酸酯与之作用得到碳二亚胺,之后与伯胺反应得到10种新的标题化合物,其结构经1HNMR、MS和元素分析表征。生物活性测试表明,此类衍生物对常见农作物部分菌体均表现出较大的抑制作用,其中以2-正庚氨基-3-对氟苯基-5-甲基-6-(1H-1,2,4-三唑-1-基)-噻吩并[2,3-d]嘧啶-4(3H)-酮活性最好,它对棉花枯萎菌的抑制率达90%。该系列物质相对不含氟元素的同种取代基的噻吩并嘧啶酮衍生物的杀菌活性有一定程度的提高。     

海洋放线菌JWH-09代谢产物中农用抗菌组分的分离纯化及结构鉴定

从134株海洋微生物中筛选得到放线菌JWH-09,其发酵代谢产物具有较好的抗植物病原真菌活性.根据生物活性跟踪测试,采用硅胶柱层析、薄层层析以及制备高效液相色谱等技术对JWH-09发酵产物中的抗菌活性组分进行分离纯化,得到了一种抗真菌活性化合物JWH-09-A,经ESI-MS、EI-MS、1H NMR、13C NMR、2D NMR等谱图分析,确定该活性物质的结构为1-菲羧,1,2,3,4,4a,9,10,10a-八氢-1,4a-二甲基-7-(1-甲基乙基),俗名脱氢松香酸(dehydroabietic acid).经盆栽试验证明该化合物对水稻纹枯病、黄瓜白粉病和灰霉病具有较好的防治效果.     

抗耻垢分枝杆菌菌株的筛选及活性物质的初步研究

从80株深海细菌和425株植物根际细菌中分离得到2株对耻垢分枝杆菌有稳定拮抗作用的细菌,其中多粘类芽胞杆菌KM2501-1的拮抗效果最佳;对其活性物质的理化性质进行研究,发现该活性物质能被硫酸铵沉淀、耐高温、对部分蛋白酶敏感、在pH值2.0~8.0范围内和紫外环境下稳定,分子量在10~30kDa之间,初步判断该活性物质可能是蛋白类物质;对该活性物质进行初步分离纯化,SDS-PAGE电泳结果显示,该活性物质中有蛋白存在;初步纯化的蛋白类活性物质的最小抑菌浓度在125~250μg·mL-1之间,具有深入研究的价值。     

微生物源黄酮类化合物的除草活性

菌株SPIR 94166是从广西采集的土壤样品中分离得到的具有产除草活性物质菌株，根据其形态学特征、生理生化特性和分子生物学特性等，认为菌株SPIR 94166是属于淡紫灰链霉菌。通过对菌种发酵液中除草活性物质的分离，得到3个活性组分，经NMR、红外、质谱等手段分析，这些除草活性物质分别鉴定为染料木素、黄烷酮以及槲皮素。     

根结线虫生防菌SneF8代谢产物理化性质的初步研究

SneF8是沈阳农业大学北方线虫研究所从土壤中分离到的一株生防真菌,该菌株代谢产物能够有效控制南方根结线虫引起的蔬菜根结线虫病. 研究了温度及pH对该菌株发酵液中活性物质稳定性的影响;利用捷克 8溶剂系统纸色谱及pH纸色谱等方法对该菌株中活性物质的水溶性、离子特性等一些理化性质进行了早期鉴别. 结果表明:该发酵液中除了具有大量的强酸性,强极性,易溶于水等极性有机溶剂的活性物质外,还有部分的两性活性物质存在,为这一农用抗生素的进一步纯化和结构测定提供依据.     

海洋细菌抗菌筛选及深海独岛枝芽胞杆菌A493活性物质分离鉴定

以水稻黄单胞菌等植物病原菌为指示菌,采用平板对峙法对411株海洋细菌进行了抗菌筛选,初筛获得具有抗菌活性的海洋菌株81株,复筛获得具有稳定抗菌活性的菌株7株,最后通过测定抗菌谱,得到1株抗菌谱特异并且稳定拮抗水稻黄单胞菌的深海独岛枝芽胞杆菌（Virgibacillus dokdonensis）A493.对水稻白叶枯病害的温室生防实验表明,经过A493无菌发酵上清波处理,水稻生长20 d后对水稻白叶枯病害的防治效果达到了66.7％,且对水稻的正常生长无不良影响.通过离子交换色谱法提取,再经2次薄层层析硅胶板回收分离,得到了纯化活性物质,经过ESI-MS＂分析,初步判断活性物质分子量为317 Da.Doskochilova系统纸层析结果显示活性物质很可能为新的氨基糖苷类物质.     

海洋放线菌Y-0117农用活性代谢产物的研究

在农用抗生素筛选中发现代号为Y-0117的海洋放线茵菌株所产生的代谢产物对植物病原真菌具有良好的抑制作用。对Y-0117发酵液进行萃取、硅胶柱层析、制备薄层色谱、制备HPLC,分离纯化得到两个活性组分0117A和0117B。通过紫外光谱、质谱、核磁共振等手段,确定0117A的分子式为C35H58O8,分子量为604。结构与已知化合物Bafilomycin D相同;0117 B的分子式为C42H60O12．分子量为756,结构与近期发现具有抗癌活性的已知化合物Hygrobafilomycin相同。研究发现0117B对多种植物病原真菌具有良好的抑制活性,对稻瘟病菌的最小抑制浓度为15．63μg·mL^-1。     

Antioxidant effect of the constituents of susabinori (Porphyra yezoensis)

The antioxidant activities of several extracts from Susabinori (Porphyra yezoensis) were measured by the ferric thiocyanate method and the thiobarbituric acid method. The methanol, acetone, ethyl acetate, and hexane extracts, and the chloroform-soluble and water-soluble fractions from the chloroform-methanol extract exhibited higher activities than α-tocopherol. The hot water extract showed little activity. Thin-layer chromatography analysis of the active extracts suggested the existence of several antioxidants. The activity of the chloroform soluble fraction was due to chlorophyll analogs. A strong antioxidant was isolated from the methanol extract, accompanied by several amino acids such as leucine and phenylalanine. This compound was identified as usujilene, a kind of mycosporine-glycine like amino acid.     

Allelochemical resistance of bald cypress,Taxodium distichum,heartwood to the subterranean termite,Coptotermes formosanus

The heartwood of bald cypress,Taxodium distichum (L.) Rich., resisted feeding attack by the Formosan subterranean termite,Coptotermes formosanus Shiraki. Hexane-extracted heartwood, however, was consumed at > 12 times the amount of sound heartwood eaten. A bioassay usingT. distichum sapwood as a feeding substrate was employed to assess the antitermitic activity of successive hexane, acetone, and methanol extracts of heartwood shavings and isolates derived from the active hexane extract. Two fractions, eluted from the crude hexane extract by liquid chromatography, significantly reduced termite feeding compared to the parent extract, while a third fraction was less active than the original hexane extract. Each fraction contained one major component. All three components were structurally related diterpenes. The two most active heartwood constituents were identified by GC-MS and NMR as ferruginol and manool, while the third and least active, but most prevalent, compound in heartwood was identified as nezukol. Results of bioassays suggest that these allelochemicals act principally as feeding deterrents with accompanying termite mortality due to starvation.     

Formation of fluorescent substances from degradation products of methyl linoleate hydroperoxides with amino compound

The degradation products formed from methyl linoleate hydroperoxides by reaction with heme were fractionated by Sephadex LH-20 column chromatography and by reverse-phase high performance liquid chromatography, and the ability of each compound to form fluorescent substances through reaction with amino compound was compared. Maximum formation of fluorescent substances was obtained from monomeric degradation products with amino compound, but low molecular weight aldehydes such as hexanal, 2-hexenal and 2,4-decadienal, formed only a small amount of fluorescent substances. However, the major monomeric degradation products described previously, the hydroxy-, keto- and epoxy-derivatives, do not significantly contribute to the formation of fluorescent substances through reaction with amino compound. It was suggested that formation of fluorescent substances from lipid peroxides with amino compound may originate from a precursor present in monomeric degradation products formed from hydroperoxide of methyl linoleate during lipid peroxidation, and that low molecular weight aliphatic aldehydes are not involved in fluorescent substance formation. Moreover, the majority of TBA-reactive substances in secondary oxidation products prepared from autoxidized methyl linoleate are also unrelated to the formation of fluorescent substances through reaction with amino compound.     

High antioxidant activity of extracts obtained from sage by supercritical co2 extraction

The ethanolic extract of sage(Salvia officinalis L.) was separated into five fractions through reextraction with supercritical CO₂. Further fractionation of the most active antioxidant fractions by means of liquid chromatography, with silicic acid as absorbent, yielded 2H-10,4α-(epoxy methano)-phenantren-12-one-1,3,4,9,10,10αhexahydro-5, 6-dihydroxy-9α-ethoxy-1,1-dimethyl-7-(1methylethy), (rosmanol-9-ethyl ether). The same compound was isolated from the alcoholic extract of the hyssop(Hyssopus officinalis L.). Rosmanol-9-ethyl ether was shown to be one of the active antioxidant components in sage and hyssop, with activity much greater than butylated hydroxytoluene (BHT).     

干柱层析法分离中药藤黄中的新藤黄酸

目的：分离中药藤黄中的新藤黄酸。方法：采用薄层硅胶G为固定相的干层析柱,以三氯甲烷-甲醇-二乙胺（10：1：1）为流动相进行洗脱,得到一黄色结晶。结果：采用UV,IR,MS,1HNMR和13CNMR方法获得该化合物波谱数据,经与文献报道数据对比,确定所分离得到的化合物为新藤黄酸。结论：干柱层析法可以快速有效地分离中药藤黄中的新藤黄酸。     

食管癌细胞中热休克蛋白70-多肽复合物的分离

目的分离纯化癌细胞中热休克蛋白70(HSP70)-多肽复合物。方法以食管癌组织为材料,通过一系列的层析柱(ConA-Sepharose、ADP-Agarose、MonoQ及HSP70抗体亲和层析柱)进行分离及纯化。结果所分离纯化的HSP70-多肽复合物相对分子质量与预期相符。结论为提取肿瘤HSP70-多肽复合物提供了具体方法,并为研制多肽疫苗奠定了基础。     

Isolation and purification of deoxynivalenol and a new trichothecene by high pressure liquid chromatography

Deoxynivalenol (3,7,15-trihydroxy-12,l3-epoxytrichothec-9-ene-8-one) was extracted from corn with methanol/water (80:20, v/v) and purified by liquid:liquid partitioning and by preparative high pressure liquid chromatography (HPLC). This procedure was used to prepare mg quantities of toxin from field-inoculated corn for reference standards. Analysis of the isolated deoxynivalenol by analytical HPLC, gas liquid chromatography (GLC) and gas liquid chromatography/mass spectroscopy (GLC/MS) indicated the presence of a second compound similar to deoxynivalenol. This compound comigrates with deoxynivalenol on thin layer chromatography plates in chloroform/methanol (90:10, v/v), but can be separated by HPLC on a reverse-phase C₈ column with methanol/water (10:90, v/v). GC/MS of the compound and the trimethylsilyl ether derivative gave parent ions of m/e 280 and 424, respectively. These data and NMR data indicate that the compound is 3,15-dihydroxy-12,13-epoxytrichothec-9-ene-8-one, a previously unreported trichothecene.