排序方式: 共有92条查询结果,搜索用时 31 毫秒
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Morsch M Girardi LG Cechinel-Filho V Meyre-Silva C Rodrigues CA 《Zeitschrift für Naturforschung. C, Journal of biosciences》2002,57(9-10):957-959
This paper describes a comparative study using different chromatographic supports (fully N-acetylated chitin, chitin and silica gel) to separate the flavonoids swertisin and 2"-O-rhamnosylswertisin from Aleurites moluccana. The results show that the flavonoids have apparently been separated by the hydrogen bond between the stationary phase (chitin and chitin-100) and flavonoids under the conditions studied. 相似文献
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Marcos da Silveira Regueira‐Neto Saulo Relison Tintino Ana Raquel Pereira da Silva Maria do Socorro Costa Cícera Datiane de Morais Oliveira‐Tintino Aline Augusti Boligon Irwin R. A. Menezes Valdir de Queiroz Balbino Henrique Douglas Melo Coutinho 《化学与生物多样性》2019,16(9)
The aim of this study was to investigate the antibacterial activity of red propolis and resin and their association with standard antibiotics to evaluate possible differences of activity. We also submitted red propolis and the resin to a HPLC analysis to confirm the botanical origin. The extracts were tested against P. aeruginosa and S. aureus alone and in association with gentamicin and imipenem. The HPLC analysis identified seven compounds with six of them present in both substances. The lowest MIC values obtained in this study were observed against S. aureus. In general, MIC values showed to be lower for red propolis against all species tested in comparison to resin. Despite the synergistic behavior to be similar for both substances, we observed that inhibitory concentrations of drugs were lower when associated with red propolis in comparison to resin. 相似文献
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de Souza MT Buzzi Fde C Cechinel Filho V Hess S Della Monache F Niero R 《Zeitschrift für Naturforschung. C, Journal of biosciences》2007,62(7-8):550-554
A mixture of triterpenes named lupeol (1), alpha-amyrin (2), beta-amyrin (3), and beta-sitosterol (4) has been isolated from the hexane fraction of Matayba elaeagnoides. In addition, scopoletin (5), umbelliferone (6), 3beta-O-D-glycopyranosyl-sitosterol (7) and betulin (8) were isolated from the chloroform fraction. All the structures were identified by spectroscopic techniques in accordance with literature data. The extracts (hydroalcoholic and methanolic) and some fractions (hexane, chloroform, ethyl acetate and butanol) exerted promising antinociceptive effects in mice. In addition, we have tested the pure compound betulin (8). When analyzed against induced pain using the writhing test (3-10 mg kg(-1), i.p.), betulin showed a dose-dependent effect with a calculated ID50 value of 7.74 (6.53-9.17) mg kg(-1) [17.5 (14.7-20.7) micromol kg(-1)] and a maximal inhibition (MI) of 58.3% in relation to the control group. When evaluated in the formalin test (3-10 mg kg(-1), i.p.), this compound inhibited both phases of pain (neurogenic and inflammatory pain), with calculated ID50 values of 18.3 (17.7-18.9) and 8.3 (7.7-8.9) mg kg(-1) [41.5 (38.4-42.7) and 18.8 (17.6-19.9) micromol kg(-1)] and maximal inhibition of 40.8 and 64.39% for the first and second phases, respectively. Using the same models, this compound was several times more active than two clinically used drugs, namely aspirin and paracetamol, suggesting that its main active principle is related to the antinociceptive effect found for the chloroform fraction of M. elaeagnoids barks. 相似文献
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Rosolem Ciro A. Witacker João P. T. Vanzolini Silvelena Ramos Valdir J. 《Plant and Soil》1999,212(2):183-188
Plant and Soil - Toxic levels of Al and low availability of Ca have been shown to decrease root growth, which can also be affected by P availability. In the current experiment, initial plant growth... 相似文献
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Lilian de Oliveira Machado Leila do Nascimento Vieira Valdir Marcos Stefenon Fábio de Oliveira Pedrosa Emanuel Maltempi de Souza Miguel Pedro Guerra Rubens Onofre Nodari 《Genetica》2017,145(2):163-174
Given their distribution, importance, and richness, Myrtaceae species comprise a model system for studying the evolution of tropical plant diversity. In addition, chloroplast (cp) genome sequencing is an efficient tool for phylogenetic relationship studies. Feijoa [Acca sellowiana (O. Berg) Burret; CN: pineapple-guava] is a Myrtaceae species that occurs naturally in southern Brazil and northern Uruguay. Feijoa is known for its exquisite perfume and flavorful fruits, pharmacological properties, ornamental value and increasing economic relevance. In the present work, we reported the complete cp genome of feijoa. The feijoa cp genome is a circular molecule of 159,370 bp with a quadripartite structure containing two single copy regions, a Large Single Copy region (LSC 88,028 bp) and a Small Single Copy region (SSC 18,598 bp) separated by Inverted Repeat regions (IRs 26,372 bp). The genome structure, gene order, GC content and codon usage are similar to those of typical angiosperm cp genomes. When compared to other cp genome sequences of Myrtaceae, feijoa showed closest relationship with pitanga (Eugenia uniflora L.). Furthermore, a comparison of pitanga synonymous (Ks) and nonsynonymous (Ka) substitution rates revealed extremely low values. Maximum Likelihood and Bayesian Inference analyses produced phylogenomic trees identical in topology. These trees supported monophyly of three Myrtoideae clades. 相似文献
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Maria Paloma S. Barros Camila T. Fran?a Rosanny Holanda F. B. Lins Milena Danda V. Santos Ednaldo J. Silva Maria Betania M. Oliveira Vladimir M. Silveira-Filho Ant?nio M. Rezende Valdir Q. Balbino Tereza Cristina Leal-Balbino 《PloS one》2014,9(9)
The potential use of CRISPR loci genotyping to elucidate population dynamics and microevolution of 146 Yersinia pestis strains from different biovars and locations was investigated in this work. The majority of strains from the Orientalis biovar presented specific spacer arrays, allowing for the establishment of a CRISPR signature for their respective isolates. Twenty-one new spacers were found in the Y. pestis strains from plague foci in Brazil. Ninety-three (64%) strains were grouped in the G1 genotype, whereas the others were distributed in 35 genotypes. This study allowed observing a microevolutionary process in a group of Y. pestis isolated from Brazil. We also identified specific genotypes of Y. pestis that were important for the establishment of the bacteria in plague foci in Brazil. The data have provided supporting evidence for the diversity and dynamics of CRISPR loci present in the genome of Y. pestis strains from plague foci in Brazil. 相似文献
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