黄蜻幼虫肠道菌QTYC01除草活性代谢产物的分离和鉴定

【目的】从黄蜻幼虫肠道中分离出具有除草活性的真菌,并在其代谢产物中寻找具有除草活性的先导化合物。【方法】采用涂布平板法对黄蜻幼虫肠道共生真菌进行分离,通过形态学观察和5.8S r RNA序列分析初步确定目标菌株QTYC01的分类地位。利用离体的方法测定菌株发酵液及其乙酸乙酯提取物的除草活性以及粗提物对常见农作物的安全性;利用盆栽方法测定发酵液对稗草幼苗的活性。运用重结晶的方法对发酵产物进行分离、纯化,利用质谱和核磁共振谱分析鉴定出化合物的结构。【结果】菌株QTYC01被鉴定为Curvularia crepinii。离体活性测试发现QTYC01发酵液可显著抑制稗草和反枝苋幼根的生长,其抑制率分别可达95.0%和90.1%,并可使经喷施发酵液的稗草幼苗的受害率达到71.1%。发酵液的乙酸乙酯提取物对稗草和反枝苋幼根具有很好的抑制效果,在100μg/m L的浓度条件下,粗提物对稗草和反枝苋的抑制活性分别为56.8%和71.2%,且在该浓度条件下对一些常见农作物具有很好的安全性,其抑制率均低于32.6%。进一步从其乙酸乙酯提取物中分离得到化合物(5Z)-7-oxozeaenol,活性测试表明化合物具有较好的抑制反枝苋活性,其IC_(50)为4.8μg/m L。【结论】菌株QTYC01具有开发为新型微生物除草剂的潜力。     

植物病原真菌抑制杂草的活性筛选及菌株CY-H的活性代谢产物

【目的】分离并鉴定具有较好除草活性的植物病原真菌菌株,进一步分离活性化合物,为开发新型生物源除草剂奠定一定的基础。【方法】采用固体培养基接种法分离纯化植物病原真菌,通过形态学特征观察和5.8S rDNA测序鉴定目标菌株;在活性筛选追踪下,对活性组分进行追踪分离及纯化,经波谱分析确定活性单体化合物结构;采用培养皿生物分析法测定活性单体化合物的除草活性及对常见作物的安全性。【结果】茶叶致病菌CY-H具有较好的除草活性,其发酵液对稗草和反枝苋根的抑制率分别为94.6%和77.3%。CY-H被鉴定为间座壳属菌(Diaporthe sp.)。从CY-H菌中分离得到单体化合物CY1被鉴定为cytosporaphenones C。在供试浓度为100μg/mL时,CY1具有较好的抑制反枝苋根的活性,抑制率为57.1%,且其对小麦和油菜的安全性较好,抑制率均在20%左右。【结论】茶叶致病菌CY-H具有开发成微生物源除草剂的潜力。     

塔宾曲霉L-27菌株的分离鉴定及其发酵液除草潜力

【背景】微生物源天然产物是新农药研究开发的热点之一。【目的】从土壤中分离筛选代谢产物具有除草潜力的真菌菌株。【方法】培养皿滤纸法测定分离菌株发酵液对植物幼苗生长的抑制作用及抑制作用稳定性,显微观察结合rDNAITS序列分析鉴定菌株。【结果】在分离的30株土壤真菌中,L-27菌株发酵液对小麦幼苗生长抑制最显著,对根、茎抑制率分别为79.4%、67.3%。基于菌落形态、菌体显微观察和rDNA ITS基因序列分析,分离菌株L-27被鉴定为塔宾曲霉(Aspergillus tubingensis)。进一步测定发现,L-27菌株发酵液完全抑制反枝苋、马齿苋、稗草的幼苗生长,对圆叶牵牛幼苗根、茎的抑制率分别为100%、77.8%。L-27菌株发酵液对小麦幼苗生长的抑制作用表现出良好的热稳定性、酸碱稳定性和紫外光照射稳定性。发酵液在120°C加热20 min,根、茎生长抑制率分别为100%和73.8%;将发酵液调至pH 2.0-12.0并保持1 h,再调回初始pH值,对根、茎生长的抑制率均达100%;发酵液经紫外光照射5-240 min,抑制率分别为100%和84.3%-91.7%。【结论】分离的塔宾曲霉L-27菌株发酵液具有开发微生物源除草剂的潜力。     

一株放线菌代谢产物除草活性的初步研究

从土壤中分离筛选出1株编号为Z40的链霉菌菌株,其代谢产物具有明显的除草活性。室内生物测定结果表明,Z40菌株发酵液干物质的除草活性主要表现为抑制生长作用。对反枝苋的主根和主茎生长抑制中浓度(EC50)分别为276.76 mg/L和1 609.37 mg/L,对狗尾草的主根和主茎生长抑制中浓度分别为501.81mg/L和629.01 mg/L。浓度为10 000 mg/L对油菜的萌发抑制率和主茎生长抑制率均为100.00%,而对小麦的生长发育没有明显影响。田间试验结果表明,Z40菌株代谢产物对稗、狗尾草、铁苋菜的防治效果均在80%以上,抑制率分别为80.30%,81.59%和88.71%。     

马蜂肠道菌抑制反枝苋的活性筛选及菌株MF06的活性代谢产物

摘要:【目的】研究马蜂肠道真菌对反枝苋的抑制活性,为开发微生物源除草剂奠定基础。【方法】通过测试11种肠道真菌发酵液对反枝苋根生长的抑制效果筛选出活性菌株MF06。通过形态学观察和分子生物学鉴定确定MF06的分类地位。通过硅胶柱层析法、薄层层析法、葡聚糖凝胶柱层析法对乙酸乙酯粗提物进行分离、纯化,得到代谢产物1,研究代谢产物1对反枝苋根生长的抑制作用。利用核磁共振谱和质谱确定代谢产物1的化学结构。【结果】经形态学观察和ITS序列分析确定MF06菌株为尖孢镰刀菌(Fusarium oxysporum)。当供试质量浓度为100 μg/mL时,该菌株发酵液的乙酸乙酯提取物对反枝苋根生长的抑制率大于68%。从乙酸乙酯粗提物中分离得到代谢产物1,经过结构鉴定为镰刀菌酸与9,10-脱氢镰刀菌酸以1:1比例形成的混合物。活性测试表明代谢产物1对反枝苋根生长具有很强的抑制作用,抑制活性的IC50值为(0.51±0.18)μg/mL,与阳性对照药2,4-二氯苯氧乙酸的活性［IC50值为(0.30±0.14)μg/mL］相当。【结论】MF06菌株具有开发为微生物源除草剂的潜力。     

黄蜻幼虫肠道分离菌QTYC38活性代谢产物的分离和鉴定

【目的】黄蜻幼虫肠道分离菌QTYC38菌株的鉴定及抗菌除草活性代谢物的研究。【方法】通过形态学观察及分子生物学ITS序列分析,对菌株QTYC38进行鉴定。利用生长速率法和琼脂扩散法测定菌株粗提物及其单体化合物的抗菌活性,结合培养皿生物分析法测定菌株粗提物及其单体化合物的除草活性。同时运用多种色谱方法分离发酵产物中的活性成分,并根据质谱和核磁共振谱数据确定其结构。【结果】菌株QTYC38被鉴定为浅黄新萨托菌Neosartorya aureola,在供试浓度为100μg/mL时,其粗提物对稗草和反枝苋的生长抑制活性较好,抑制率均大于65%;当供试浓度为30μg/滤纸片时,其对金黄色葡萄球菌(Staphyloccocus aureus)具有较好的抑菌活性,抑菌圈直径为22.7 mm,与阳性对照药(硫酸庆大霉素23.2 mm)活性相当。从该菌固体发酵产物中分离纯化得到4个单体化合物:helvolic acid(1),aromatic lactones(2),questin(3)和erogosterol(4)。其中,化合物1对枯草芽孢杆菌(Bacillus subtilis)和金黄色葡萄球菌(S.aureus)均具有较好的生长抑制活性,最低抑菌浓度分别为3.1和1.5μg/mL;当供试浓度为100μg/mL时,化合物3和化合物4分别对杨树溃疡病菌(Dothiorella gregaria)和小麦赤霉病菌(Fusarium graminearum)具有较好的抑制效果,抑制率分别为52.4%和72.3%。【结论】菌株QTYC38具有开发为微生物源除草剂和新型杀菌剂的潜能。     

‘海螺’望春花内生真菌EF-WCH-51鉴定及其抑制葫芦科刺盘孢活性成分分析

【背景】药用植物内生真菌产生的次生代谢产物具有多种抗菌活性,因而具有生防菌开发潜力。【目的】鉴定一株对葫芦科刺盘孢(Colletotrichumorbiculare)有抑菌活性的‘海螺’望春花内生真菌EF-WCH-51,并确定其主要抑菌活性成分。【方法】根据形态特征并结合分子序列鉴定EF-WCH-51菌株,利用生长速率法确定EF-WCH-51抑菌活性,并采用半制备型HPLC、HPLC-MS/MS对其活性成分进行分离鉴定。【结果】供试菌株EF-WCH-51为丝枝蜡蚧菌(Lecanicillium aphanocladii),其发酵液粗提物对葫芦科刺盘孢菌丝生长具有较强抑制作用,EC50为0.086 2 mg/mL;抑菌活性组分A (0.085 0 mg/mL)对葫芦科刺盘孢抑制率达到76.08%,通过查询MS、MS/MS数据库以及与相关文献对比,确定该化合物为卵孢菌素(oosporein)。【结论】本研究发现丝枝蜡蚧菌对葫芦科刺盘孢具有较好的抑菌活性,其主要抑菌活性成分为卵孢菌素,具有作为瓜类炭疽病生防菌株的潜力。     

红海榄根际土壤来源的泡盛曲霉（Aspergillus awamori）F12及其代谢产物的抗菌活性分析

摘要：【目的】鉴定一株来自于红海榄根际土壤并具有分泌抑菌活性代谢产物的真菌菌株F12,并从其发酵液乙酸乙酯浸膏中分离抑菌活性成分。【方法】通过形态学观察以及ITS序列分析方法对菌株F12进行鉴定;利用色谱技术分离发酵液乙酸乙酯浸膏中的次生代谢产物,根据化合物的质谱、氢谱、碳谱以及理化性质确定其结构,并检测它们对细菌生长的抑制作用。【结果】菌株F12被鉴定为Aspergillus awamori strain F12;从其发酵液乙酸乙酯浸膏中分离到3种化合物：1,4-二甲氧基苯（1）、大黄素（2）和3,6-二苯甲基哌嗪-2,5-二酮（3）,其中化合物1属于在本属真菌中首次报道。化合物2对金黄色葡萄球菌和枯草芽孢杆菌的生长具有明显的抑制作用,最低抑菌浓度（MIC）分别为16ng/L和32ng/L,化合物1和3对上述菌株的生长无明显的抑制活性。【结论】首次发现从红海榄根际土壤中分离到的泡盛曲霉（Aspergillus awamori）菌株F12具有合成1,4-二甲氧基苯和大黄素的能力,其中后者对微生物的生长具有明显的抑制作用。     

胶孢炭疽菌生防放线菌SD-29的鉴定及抗菌活性评价

【背景】胶孢炭疽菌是引起橡胶炭疽病的一种重要病原菌,可导致橡胶树产胶量下降。【目的】从山东青岛一农田土壤中分离出一株胶孢炭疽菌生防放线菌SD-29,并对其进行鉴定及抗菌活性评价。【方法】采用对峙生长法及菌丝生长速率法对菌株SD-29的拮抗活性进行鉴定;利用乙酸乙酯萃取法提取菌株SD-29发酵液粗提物并进行活性评价;根据菌株SD-29的形态特征、生理生化及16S rRNA基因序列进行鉴定。【结果】菌株SD-29对胶孢炭疽菌具有较强的抑制活性,皿内抑制活性达到82.6%。发酵液粗提物对菌丝生长的EC50为13.6μg/mL,100μg/mL的粗提物对胶孢炭疽菌孢子萌发抑制率达到63.16%,其对感炭疽病橡胶叶片的防治效果达到48.96%。根据该菌的形态特征、生理生化特征及16S rRNA基因序列分析鉴定菌株SD-29为Streptomyces yatensis。【结论】菌株SD-29对胶孢炭疽菌有较强的防治效果,具有潜在的应用价值。     

白蚁巢拮抗放线菌BYC01代谢产物的分离和鉴定

【目的】从白蚁巢中分离出具有抗菌活性的放线菌,并在其代谢产物中寻找具有抗菌活性的先导化合物。【方法】通过形态学观察和16S rRNA序列分析初步确定目标菌株BYC 01的分类地位。利用生长速率法和琼脂扩散法测定其代谢产物的抗菌活性。并通过大量发酵提取浸膏,运用多种色谱方法对发酵产物进行分离、纯化,利用质谱和核磁共振谱分析鉴定出化合物的结构。【结果】通过形态学观察和16S rRNA序列分析,菌株BYC 01被鉴定为紫红链霉菌(Streptomyces violaceoruber)。BYC 01发酵液不同极性溶剂萃取物的抗菌活性结果表明其有效抑菌物质主要存在于中等极性的乙酸乙酯部位。在供试浓度为100μg/mL时,BYC 01发酵液乙酸乙酯萃取物对苹果树腐烂病菌具有强烈的抑制作用,抑制率大于90%;对水稻纹枯病菌和杨树溃疡病菌具有较好抑制活性,抑制率均大于60%;在供试浓度为30μg/滤纸片时,与阳性对照相比,乙酸乙酯提取物对白色念珠菌、金黄色葡萄球菌、大肠杆菌、枯草芽孢杆菌和水稻白叶枯病菌有中等的抑制作用,其抑菌圈直径范围为11.3 mm-16.5 mm。经质谱和核磁共振谱分析,从BYC 01发酵产物中分离到的单体化合物被鉴定为fogacin;在供试浓度为30μg/滤纸片时,化合物fogacin对白色念珠菌生长的抑制作用与阳性对照两性霉素相当,其抑菌圈大小分别为19.3 mm和20.1 mm。【结论】菌株BYC 01具有开发为微生物杀菌剂的潜力。     

Characterization of SSEA-1 glycolipids from the brain of a patient with fucosidosis

Neutral glycolipids from the brain of a patient with Fucosidosis were analyzed and two complex glycolipids containing five and eight sugars were isolated from the cortical grey matter. These two glycolipids reacted with antibodies recognizing the SSEA-1 [Le^x(X)] carbohydrate determinant. SSEA-1 glycolipids are normally expressed in human embryonic brain but are found in only small amounts in postnatal human brain. The accumulation of the two SSEA-1 glycolipids in Fucosidosis brain thus represents a defect which affects the normal developmentally regulated decrease in postnatal, expression of these glycolipids, and may be a contributing factor in the abnormal brain development associated with the disease. Chemical characterization of the two isolated glycolipids by gas chromatographic and mass spectrometric analyses has identified the two glycolipids as lacto-N-fucopentaosylceramide (III) and difucosyl-neolactonorhexaosylceramide.Abbreviations DCl direct chemical ionization - FAB tastatiom bombardment - GC gas chromatography - GSLs glycosphingolipids - MS mass spectrometry - SSEA-1 stage specific embryonic antigen-1 - TLC thin layer chromatographys     

Phylogeny of cardinalfishes (Teleostei: Gobiiformes: Apogonidae) and the evolution of visceral bioluminescence

The cardinalfishes (Apogonidae) are a diverse clade of small, mostly reef-dwelling fishes, for which a variety of morphological data have not yielded a consistent phylogeny. We use DNA sequence to hypothesize phylogenetic relationships within Apogonidae and among apogonids and other acanthomorph families, to examine patterns of evolution including the distribution of a visceral bioluminescence system. In conformance with previous studies, Apogonidae is placed in a clade with Pempheridae, Kurtidae, Leiognathidae, and Gobioidei. The apogonid genus Pseudamia is recovered outside the remainder of the family, not as sister to the superficially similar genus Gymnapogon. Species sampled from the Caribbean and Western Atlantic (Phaeoptyx, Astrapogon, and some Apogon species) form a clade, as do the larger-bodied Glossamia and Cheilodipterus. Incidence of visceral bioluminescence is found scattered throughout the phylogeny, independently for each group in which it is present. Examination of the fine structure of the visceral bioluminescence system through histology shows that light organs exhibit a range of morphologies, with some composed of complex masses of tubules (Siphamia, Pempheris, Parapriacanthus) and others lacking tubules but containing chambers formed by folds of the visceral epithelium (Acropoma, Archamia, Jaydia, and Rhabdamia). Light organs in Siphamia, Acropoma, Pempheris and Parapriacanthus are distinct from but connected to the gut; those in Archamia, Jaydia, and Rhabdamia are simply portions of the intestinal tract, and are little differentiated from the surrounding tissues. The presence or absence of symbiotic luminescent bacteria does not correlate with light organ structure; the tubular light organs of Siphamia and chambered tubes of Acropoma house bacteria, those in Pempheridae and the other Apogonidae do not.     

Structural Peculiarities of Na+,K+-ATPase Isozymes from the Calf Brain

Functionally active preparations of Na⁺,K⁺-ATPase isozymes from calf brain that contain catalytic subunits of three types (1, 2, and 3) were obtained using two approaches: a selective removal of contaminating proteins by the Jorgensen method and a selective solubilization of the enzyme with subsequent reconstitution of their membrane structure by the Esmann method. The ouabain inhibition constants were determined for the isozymes. The real isozyme composition of the Na⁺ pump from the grey matter containing glial cells and the brain stem containing neurons was determined. The plasma membranes of glial cells were shown to contain mainly Na⁺,K⁺-ATPase of the 11 type and minor amounts of isozymes of the 22(1) and the 31(2) type. The axolemma contains 21 and 31 isozymes. A carbohydrate analysis indicated that 11 enzyme preparations from the brain grey matter substantially differ from the renal enzymes of the same composition in the glycosylation of the 1 isoform. An enhanced sensitivity of the 3 catalytic subunit of Na⁺,K⁺-ATPase from neurons to endogenous proteolysis was found. A point of specific proteolysis in the amino acid sequence PNDNR⁴⁹² Y⁴⁹³ was localized (residue numbering is that of the human 3 subunit). This sequence corresponds to one of the regions of the greatest variability in 1-, 2-, 3-, and 4-subunits, but at the same time, it is characteristic of the 3 isoforms of various species. The presence of the 3 isoform of tubulin (cytoskeletal protein) was found for the first time in the high-molecular-mass Na⁺,K⁺-ATPase 31 isozyme complex isolated from the axolemma of brain stem neurons, and its binding to the 3 catalytic subunit was shown.     

Taxonomic status of the species of the green algal genusNeochloris

Komárek has recently reviewed the various species assigned to the green algal genusNeochloris Starr (Chlorococcales, Chlorococcaceae) and removed those with uninucleate vegetative cells to a new genus,Ettlia. Watanabe & Floyd, unaware ofKomárek's work, also reviewed the species ofNeochloris and distributed them among three genera—Neochloris, Chlorococcopsis gen. nov., andParietochloris gen. nov.—on the basis of details of the covering of the zoospore and the arrangement of the basal bodies of the flagellar apparatus. This paper reconciles these two treatments and makes additional recommendations at the ranks of genus, family, order, and class.     

Elucidation of Structure of Lipid A from the Marine Gram-Negative Bacterium Pseudoalteromonas haloplanktis ATCC 14393T

The chemical structure of lipid A, from the marine -proteobacterium Pseudoalteromonas haloplanktis 14393, a main product of lipopolysaccharide hydrolysis (1% AcOH), was determined using chemical methods and NMR spectroscopy. The lipid A was shown to be -1,6-glucosaminobiose 1,4-diphosphate acylated with two (R)-3-hydroxyalkanoic acid residues at C3 and C3 and amidated with one (R)-3-hydroxydodecanoyl and one (R)-3-dodecanoyloxydodecanoyl residue at N2 and N2, respectively.     

The evolution of the Hox cluster: insights from outgroups

Two burgeoning research trends are helping to reconstruct the evolution of the Hox cluster with greater detail and clarity. First, Hox genes are being studied in a broader phylogenetic sampling of taxa: the past year has witnessed important new data from teleost fishes, onychophorans, myriapods, polychaetes, glossiphoniid leeches, ribbon worms, and sea anemones. Second, commonly accepted notions of animal relationships are being challenged by alternative phylogenetic hypotheses that are causing us to rethink the evolutionary relationships of important metazoan lineages, especially arthropods, annelids, nematodes, and platyhelminthes.     

A molecular phylogeny of Hebeloma species from Europe

In order to widen the scope of existing phylogenies of the ectomycorrhizal agaric genus Hebeloma a total of 53 new rDNA ITS sequences from that genus was generated, augmented by sequences retrieved from GenBank, and analysed using Bayesian, strict consensus and neighbour joining methods. The lignicolous Hebelomina neerlandica, Gymnopilus penetrans, and two species of Galerina served as outgroup taxa. Anamika indica, as well as representatives of the genera Hymenogaster and Naucoria, were included to test the monophyly of Hebeloma, which is confirmed by the results. Hebeloma, Naucoria, Hymenogaster and Anamika indica cluster in a strongly supported monophyletic hebelomatoid clade. All trees largely reflect the current infrageneric classification within Hebeloma, and divide the genus into mostly well-supported monophyletic groups surrounding H. crustuliniforme, H. velutipes, H. sacchariolens, H. sinapizans, and H. radicosum, with H. sarcophyllum being shown at an independent position; however this is not well supported. The section Indusiata divides with strong support into three groups, the position of the pleurocystidiate Hebeloma cistophilum suggests the possible existence of a third subsection within sect. Indusiata. Subsection Sacchariolentia is raised to the rank of section.     

Systematic significance of mature embryo of bamboos

The mature embryo of seven species belonging to five genera of Indian bamboos is described. In all these the basic pattern of embryo organisation is same: the scutellar and coleoptilar bundles are not separated by an internode, the epiblast is absent, the lower portion of the scutellum and the coleorhiza are separated by a cleft and the margins of embryonic leaves overlap. The features unique to fleshy fruited bamboos are: presence of a massive scutellum, the juxtaposition of plumule and radicle and the occurrence of a bud in the axil of the coleoptile. The fleshy fruit bearing bamboos should be classified into one group, the tribeMelocanneae. Evidence is provided to recognise additional groups in the subfamilyBambusoideae.     

Demographic characteristics of an intertidal bay goby (Lepidogobius lepidus)

Synopsis In a fourteen month study (May 1976 – June 1977) I examined the following characteristics of an intertidal bay goby (Lepidogobius lepidus) in Morro Bay, California, U.S.A.: annual and seasonal patterns of abundance, age composition and growth rates, survivorship and mortality patterns, and the reproductive cycle for female gobies. Fishes were collected with the aid of quinaldine and otoliths and ovaries removed. Age and growth rates were estimated from otolith annuli using a back calculation formula and a Brody-Bertalanffy growth curve. Mortality rates were derived using the methods of Heincke (1913), Robson & Chapman (1960), mean age, and a catch curve (Ricker 1975). A gonad index was used to describe the annual reproductive cycle. Results indicated that abundance fluctuated seasonally and that these fluctuations appeared to be caused by reproductive emigrations. Bay gobies reached an age of 7+ and a standard length of 87 mm. Growth was relatively constant (6 mm yr⁻¹) until age 5, at which point it began to decline. The mean rates of survivorship, mortality, and instantaneous mortality were 0.75, 0.25, and 0.29 respectively. Mortality rates for individual age classes ranged from 0.13 to 0.51 and increased with age. This stock appears to reproduce mainly during the winter.