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991.
Byoung-In Sang Won-Kwon Lee Katsutoshi Hori Hajime Unno 《World journal of microbiology & biotechnology》2006,22(1):51-57
Summary Poly(3-hydroxybutyrate) [P(3HB)] depolymerase was purified from a poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)]-degrading fungus, Paecilomyces lilacinus F4-5 by hydrophobic and ion exchange column chromatography, and showed a molecular mass of 45 kDa. The optimum temperature
and pH of the P(3HB) depolymerase were 50 °C and 7.0, respectively. The enzyme was stable for at least 30 min at temperatures
below 40 °C, while the activity abruptly decreased over 55 °C. Enzymatic P(3HB-co-3HV) degradation showed a similar degradation pattern to that of film overlaid by fungal hyphae. It reflects that the fungal
degradation of P(3HB-co-3HV) in soil is mainly caused by extracellular depolymerases. 相似文献
992.
L. D. Sette M. R. Z. Passarini C. Delarmelina F. Salati M. C. T. Duarte 《World journal of microbiology & biotechnology》2006,22(11):1185-1195
Endophytic filamentous fungi from coffee plants (Coffea arabica and C. robusta) deposited in the Brazilian Collection of Environmental and Industrial Microorganisms (CBMAI) were characterized taxonomically by using molecular tools and investigated concerning their antimicrobial activity against different human pathogenic bacteria. Thirty-seven out of 39 CBMAI strains investigated were identified to at least at genus level by ITS and rDNA D1/D2 sequencing and phylogenetic analyses. Bioactivity screening of fungal extracts against Salmonella choleraesuis (CBMAI 484), Staphylococcus aureus (CBMAI 485), Pseudomonas aeruginosa (CBMAI 489) and against four different Escherichia coli serotypes showed that 17 fungi inhibited at least one of the bacteria studied. The endophytic fungi Trichoderma harzianum (CBMAI 43), Guignardia sp. (CBMAI 69) and Phomopsis sp. (CBMAI 164) inhibited from four to five bacterial species, while five fungi were active against all pathogenic bacteria tested and were identified as Aspergillus
versicolor (CBMAI 46), Fusarium oxysporum (CBMAI 53), Glomerella sp. (CBMAI 63) and Cladosporium spp. (CBMAI 64 and CBMAI 66). The Minimal Inhibitory Concentration (MIC) for the fungus extracts varied from 0.025 to 1.0 mg ml−1, demonstrating antimicrobial potential of some of these fungi. 相似文献
993.
Sivaprasad G Perumal PT Prabavathy VR Mathivanan N 《Bioorganic & medicinal chemistry letters》2006,16(24):6302-6305
A series of pyrazolylbisindole derivatives have been synthesized by reacting substituted pyrazole aldehydes with substituted indoles using phosphotungstic acid, a Keggin type heteropoly acid as catalyst. The synthesized pyrazolylbisindoles were evaluated for anti-microbial activities. The effect of pyrazolylbisindoles on the mycelial growth of plant pathogenic fungi is revealed. Entries 3c and 3d emerged as the most interesting compounds in this series exhibiting excellent anti-fungal activity. 相似文献
994.
A viscometric study of the biodegradation of photographic gelatin by fungi isolated from cinematographic films 总被引:2,自引:2,他引:0
C. Abrusci D. Marquina A. Del Amo T. Corrales F. Catalina 《International biodeterioration & biodegradation》2006,58(3-4):142
The biodegradation of photographic gelatin grade (Bloom 225) material was studied by viscometry in aqueous solution (at 37 °C, 6.67% w/w) using filamentous fungi isolated and identified from cinematographic film stored in different Spanish archives. From viscosity data, different variables such as molecular weight and chain scission were calculated. To ensure initial spore suspension concentration was standardized for all the biodegradation experiments, a correlation between transmittance at 530 nm of fungal spore suspensions and the corresponding cytometric determination of populations was established for all the fungal strains studied in this work. The bioassay experiments were carried out at 25 and 4 °C using an initial concentration of fungi of 4.5×105 conidia/mL except in the case of the genus Alternaria, where the concentration was 10 times lower. The fungal strains were three species of Aspergillus, i.e., A .ustus, A. nidulans var. nidulans, A. versicolor, seven Penicillium chrysogenum strains, and Cladosporium cladosporioides, Alternaria alternata, Mucor racemosus, Phoma glomerata, and Trichoderma longibrachiatum. All were gelatinase positive. Through the viscosity decay profiles with bioassay-time and the corresponding calculated chain scission, the relative quantitative gelatinase efficiency of these fungi has been evaluated. 相似文献
995.
J. Chirkova I. Irbe B. Andersons I. Andersone 《International biodeterioration & biodegradation》2006,58(3-4):162
The dynamics of the biodegradation of wood by brown-rot fungi (Coniophora puteana, Poria placenta, and Gloephyllum trabeum) was investigated by the water vapour sorption method. The change in wood microstructure characteristics (specific surface and concentration of surface hydrophilic centres) with increasing exposure time correlated with reduction in mass and change in composition. Two-to-eight-nanometer-wide micropores, whose size and volume depended on the fungal species and exposure time, appeared in the wood. Methodological aspects of the application of sorption methods should be taken into account in the interpretation of the results. 相似文献
996.
桃儿七和南山荷叶内生真菌的生物活性研究 总被引:11,自引:0,他引:11
通过研究桃儿七(Sinopodophyllum hexandrum)与南方山荷叶(Diphylleia sinensis)的内生真菌的生物活性,探讨内生真菌作为生物活性物质资源开发利用的价值。测定内生真菌发酵液的抗细菌、抗真菌、抗卤虫活性后,发现大多数菌株的发酵液都具有不同的生物活性。高活性菌株集中于镰孢霉属、柱孢属、木霉属、色串孢属。桃儿七内生真菌抗真菌活性较强,南方山荷叶内生真菌抗细菌和抗卤虫活性较强。桃儿七和南方山荷叶内生真菌是寻找有价值的活性成分的良好资源。 相似文献
997.
耐热真菌的分类鉴定及rDNA-ITS系统发育分析 总被引:1,自引:0,他引:1
分别从山东、山西、河北、陕西、河南、云南、江西、海南、新疆、内蒙古、甘肃、广州等地实地采集堆肥、培养料、草堆等标本600多份,分离鉴定出耐热真菌28种,其中包括2个中国新记录种,沙生梭孢壳Thielavia arenaria和丰孢木霉Trichoderma saturnisporum,其余26个为中国已知种。在形态分类的基础上,对所分离鉴定的28株耐热真菌及购买的3株耐热真菌,进行rDNA-ITS序列测定,所测序列片段长度为554-895bp。将所测的31个和从GenBank下载的15个耐热真菌的rDNA-ITS序列构建NJ系统发育树,该树较好地显示了耐热真菌的系统进化关系,有力地支持了形态学的观点。 相似文献
998.
999.
Helmut Brandl 《Journal of Plant Ecology》2013,6(4):265
Aims The goal of the study was to apply Fourier transform infrared (FTIR) spectroscopy followed by chemometrical data treatment for the differentiation of fungi-infected perennial ryegrass (Lolium perenne) from uninfected grass.Methods FTIR was used to rapidly discriminate between leaves of perennial ryegrass (L. perenne) infected by a fungal endophyte (Epichlo?; asexual forms: Neotyphodium) and uninfected leaves. Besides drying and grinding of the sampled leaves, no other preparation steps were needed. FTIR measurements were performed in the attenuated total reflection (ATR) mode. Aliquots of powdered leaf samples were placed on a ZnSe crystal and the spectra were collected, followed by chemometrical analysis (multidimensional factor analysis, hierarchical cluster analysis).Important findings ATR-FTIR allowed a rapid detection of fungal infections in the plant material and proved to be a fast and reliable tool for the differentiation of plant biomass without the need of time-consuming sample preparation. 相似文献
1000.
从云南西双版纳及河口热带雨林、植物园、荒坡和农田中采集混合土壤样品30余份,采用稀释平板法和土壤颗粒法从中分离获得暗色丝孢菌分离物53个,经形态鉴定分属于29属37种。其中4个为中国新记录种:尼尔布洛孢Bloxamia nilagirica、不规头梗孢Cephaliophora irregularis、单梗粘孢Haplographium delicatum和不列颠黑团孢Periconia britannica,对它们进行了描述和必要的讨论。研究过的标本(干制培养物)及活菌种保存在山东农业大学植物病理学标本室(HSAUP)。 相似文献