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[PMID]:29267499
[Au] Autor:Santos APP; Silva MDS; Costa EVL; Rufino RD; Santos VA; Ramos CS; Sarubbo LA; Porto ALF
[Ad] Endereço:Departamento de Morfologia e Fisiologia Animal, Universidade Federal Rural de Pernambuco, Recife, PE, Brasil.
[Ti] Título:Production and characterization of a biosurfactant produced by Streptomyces sp. DPUA 1559 isolated from lichens of the Amazon region.
[So] Source:Braz J Med Biol Res;51(2):e6657, 2017 Dec 11.
[Is] ISSN:1414-431X
[Cp] País de publicação:Brazil
[La] Idioma:eng
[Ab] Resumo:Surfactants are amphipathic compounds containing both hydrophilic and hydrophobic groups, capable to lower the surface or interfacial tension. Considering the advantages of the use of biosurfactants produced by microorganisms, the aim of this paper was to develop and characterize a biosurfactant produced by Streptomyces sp. DPUA1559 isolated from lichens of the Amazon region. The microorganism was cultured in a mineral medium containing 1% residual frying soybean oil as the carbon source. The kinetics of biosurfactant production was accompanied by reducing the surface tension of the culture medium from 60 to values around 27.14 mN/m, and by the emulsification index, which showed the efficiency of the biosurfactant as an emulsifier of hydrophobic compounds. The yield of the isolated biosurfactant was 1.74 g/L, in addition to the excellent capability of reducing the surface tension (25.34 mN/m), as observed from the central composite rotational design when the biosurfactant was produced at pH 8.5 at 28°C. The critical micelle concentration of the biosurfactant was determined as 0.01 g/mL. The biosurfactant showed thermal and pH stability regarding the surface tension reduction, and tolerance under high salt concentrations. The isolated biosurfactant showed no toxicity to the micro-crustacean Artemia salina, and to the seeds of lettuce (Lactuca sativa L.) and cabbage (Brassica oleracea L.). The biochemistry characterization of the biosurfactant showed a single protein band, an acid character and a molecular weight around 14.3 kDa, suggesting its glycoproteic nature. The results are promising for the industrial application of this new biosurfactant.
[Mh] Termos MeSH primário: Líquens/microbiologia
Streptomyces/metabolismo
Tensoativos/metabolismo
[Mh] Termos MeSH secundário: Análise de Variância
Contagem de Colônia Microbiana
Meios de Cultura
Eletroforese em Gel de Poliacrilamida
Fermentação
Concentração de Íons de Hidrogênio
Valores de Referência
Sementes/efeitos dos fármacos
Óleo de Soja/química
Espectroscopia de Infravermelho com Transformada de Fourier
Streptomyces/crescimento & desenvolvimento
Streptomyces/isolamento & purificação
Tensão Superficial
Tensoativos/análise
Tensoativos/química
Temperatura Ambiente
Fatores de Tempo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Culture Media); 0 (Surface-Active Agents); 8001-22-7 (Soybean Oil)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180308
[Lr] Data última revisão:
180308
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171222
[St] Status:MEDLINE


  2 / 2050 MEDLINE  
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[PMID]:29311513
[Au] Autor:Lopes TIB; Coelho RG; Honda NK
[Ad] Endereço:Instituto de Química, Universidade Federal de Mato Grosso do Sul.
[Ti] Título:Inhibition of Mushroom Tyrosinase Activity by Orsellinates.
[So] Source:Chem Pharm Bull (Tokyo);66(1):61-64, 2018.
[Is] ISSN:1347-5223
[Cp] País de publicação:Japan
[La] Idioma:eng
[Ab] Resumo:Several applications have been proposed for tyrosinase inhibitors in the pharmaceutical, food bioprocessing, and environmental industries. However, only a few compounds are known to serve as effective tyrosinase inhibitors. This study evaluated the tyrosinase-related activity of resorcinol (1), orcinol (2) lecanoric acid (3), and derivatives of this acid (4-15). Subjected to alcoholysis, lecanoric acid (3), a depside isolated from the lichen Parmotrema tinctorum, produces orsellinic acid (2,4-dihydroxy-6-methylbenzoic acid) (4) and orsellinates (2,4-dihydroxy-6-methyl benzoates) (5-15). At 0.50 mM, methyl (5), ethyl (6), n-propyl (7), tert-butyl (11), and n-cetyl orsellinates (15) acted as tyrosinase activators, whereas n-butyl (8), iso-propyl (9), sec-butyl (10), n-pentyl (12), n-hexyl (13), and n-octyl orsellinates (14) behaved as inhibitors. Tyrosinase inhibition rose with chain elongation-n-butyl (8)
[Mh] Termos MeSH primário: Agaricales/enzimologia
Inibidores Enzimáticos/farmacologia
Líquens/química
Monofenol Mono-Oxigenase/antagonistas & inibidores
Resorcinóis/farmacologia
[Mh] Termos MeSH secundário: Relação Dose-Resposta a Droga
Inibidores Enzimáticos/química
Inibidores Enzimáticos/isolamento & purificação
Cinética
Estrutura Molecular
Monofenol Mono-Oxigenase/metabolismo
Resorcinóis/química
Resorcinóis/isolamento & purificação
Relação Estrutura-Atividade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Enzyme Inhibitors); 0 (Resorcinols); 11XLA0494B (orsellinic acid); EC 1.14.18.1 (Monophenol Monooxygenase)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180213
[Lr] Data última revisão:
180213
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180110
[St] Status:MEDLINE
[do] DOI:10.1248/cpb.c17-00502


  3 / 2050 MEDLINE  
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[PMID]:29364602
[Au] Autor:Danilova OV; Belova SE; Gagarinova IV; Dedysh SN
[Ti] Título:Microbial Community Composition and Methanotroph Diversity of a Subarctic Wetland in Russia.
[So] Source:Mikrobiologiia;85(5):545-554, 2016 Sep.
[Is] ISSN:0026-3656
[Cp] País de publicação:Russia (Federation)
[La] Idioma:eng
[Ab] Resumo:This study assessed the microbial diversity, activity, and composition of methane-oxidizing communities of a subarctic wetland in Russia,with mosaic cover of Sphagnum mosses and lichens of the genera Cladonia and Cetraria. Potential methane-oxidizing activity of peat sampled from lichen-dominated wetland sites was higher than that in the sites dominated by Sphagnum mosses. In peat from lichendominated sites, major bacterial groups identified by high-throughput sequencing of the 16S rRNA genes were the Acidobacteria (35.4-41.2% of total 16S rRNA gene reads), Alphaproteobacteria (19.1-24.2%), Gammaproteobacteria (7.9-11.1%), Actinobacteria (5.5-13.2%), Planctomycetes (7.2-9.5%), and Verrucomicrobia (5.1-9.5%). The distinctive feature of this community was high proportion of Subdivision 2 Acidobacteria, which are not char- acteristic for boreal Sphagnum peat bogs. Methanotrophic community composition was determined by mo- lecular analysis of the pmoA gene encoding particulate methane monooxygenase. Most (-80%) of all pmoA gene fragments revealed in peat from lichen-dominated sites belonged to the phylogenetic lineage represented by a microaerobic spiral-shaped methanotroph, "Candidatus Methylospira mobilis." Members of the genus Methylocystis, which are typical inhabitants of boreal Sphagnum peat bogs, represented only a minor group of indigenous methanotrophs. The specific feature of a methanotrophic community in peat from lichen-dominated sites was the presence of uncultivated USCa (Upland Soil Cluster alpha) methanotrophs, which are typical for acidic upland soils showing atmospheric methane oxidation. The methanotrophic community composition in lichen-dominated sites of a tundra wetland, therefore, was markedly different from that in bo- real Sphagnum peat bogs.
[Mh] Termos MeSH primário: Proteínas de Bactérias/genética
Água Subterrânea/microbiologia
Metano/metabolismo
Consórcios Microbianos/fisiologia
Oxigenases/genética
[Mh] Termos MeSH secundário: Acidobacteria/classificação
Acidobacteria/genética
Acidobacteria/isolamento & purificação
Acidobacteria/metabolismo
Actinobacteria/classificação
Actinobacteria/genética
Actinobacteria/isolamento & purificação
Actinobacteria/metabolismo
Alphaproteobacteria/classificação
Alphaproteobacteria/genética
Alphaproteobacteria/isolamento & purificação
Alphaproteobacteria/metabolismo
Regiões Árticas
Proteínas de Bactérias/metabolismo
Briófitas/fisiologia
Gammaproteobacteria/classificação
Gammaproteobacteria/genética
Gammaproteobacteria/isolamento & purificação
Gammaproteobacteria/metabolismo
Expressão Gênica
Líquens/fisiologia
Metano/química
Oxigenases/metabolismo
Filogenia
Planctomycetales/classificação
Planctomycetales/genética
Planctomycetales/isolamento & purificação
Planctomycetales/metabolismo
Federação Russa
Verrucomicrobia/classificação
Verrucomicrobia/genética
Verrucomicrobia/isolamento & purificação
Verrucomicrobia/metabolismo
Zonas Úmidas
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); EC 1.13.- (Oxygenases); EC 1.14.13.25 (methane monooxygenase); OP0UW79H66 (Methane)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180208
[Lr] Data última revisão:
180208
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180125
[St] Status:MEDLINE


  4 / 2050 MEDLINE  
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[PMID]:28967570
[Au] Autor:Welden NA; Wolseley PA; Ashmore MR
[Ad] Endereço:Stockholm Environment Institute, University of York, UK; Open University, Milton Keynes, UK.
[Ti] Título:Citizen science identifies the effects of nitrogen deposition, climate and tree species on epiphytic lichens across the UK.
[So] Source:Environ Pollut;232:80-89, 2018 Jan.
[Is] ISSN:1873-6424
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:A national citizen survey quantified the abundance of epiphytic lichens that are known to be either sensitive or tolerant to nitrogen (N) deposition. Records were collected across the UK from over 10,000 individual trees of 22 deciduous species. Mean abundance of tolerant and sensitive lichens was related to mean N deposition rates and climatic variables at a 5 km scale, and the response of lichens was compared on the three most common trees (Quercus, Fraxinus and Acer) and by assigning all 22 tree species to three bark pH groups. The abundance of N-sensitive lichens on trunks decreased with increasing total N deposition, while that of N-tolerant lichens increased. The abundance of N-sensitive lichens on trunks was reduced close to a busy road, while the abundance of N-tolerant lichens increased. The abundance of N-tolerant lichen species on trunks was lower on Quercus and other low bark pH species, but the abundance of N-sensitive lichens was similar on different tree species. Lichen abundance relationships with total N deposition did not differ between tree species or bark pH groups. The response of N-sensitive lichens to reduced nitrogen was greater than to oxidised N, and the response of N-tolerant lichens was greater to oxidised N than to reduced N. There were differences in the response of N-sensitive and N-tolerant lichens to rainfall, humidity and temperature. Relationships with N deposition and climatic variables were similar for lichen presence on twigs as for lichen abundance on trunks, but N-sensitive lichens increased, rather than decreased, on twigs of Quercus/low bark pH species. The results demonstrate the unique power of citizen science to detect and quantify the air pollution impacts over a wide geographical range, and specifically to contribute to understanding of lichen responses to different chemical forms of N deposition, local pollution sources and bark chemistry.
[Mh] Termos MeSH primário: Poluentes Atmosféricos/análise
Monitoramento Ambiental/métodos
Líquens/química
Nitrogênio/análise
[Mh] Termos MeSH secundário: Acer
Poluição do Ar/estatística & dados numéricos
Poluição Ambiental
Líquens/fisiologia
Quercus
Árvores
Reino Unido
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Air Pollutants); N762921K75 (Nitrogen)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180208
[Lr] Data última revisão:
180208
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171003
[St] Status:MEDLINE


  5 / 2050 MEDLINE  
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[PMID]:29199255
[Au] Autor:Tanahashi T
[Ad] Endereço:Kobe Pharmaceutical University.
[Ti] Título:[Diversity of Secondary Metabolites from Some Medicinal Plants and Cultivated Lichen Mycobionts].
[So] Source:Yakugaku Zasshi;137(12):1443-1482, 2017.
[Is] ISSN:1347-5231
[Cp] País de publicação:Japan
[La] Idioma:jpn
[Ab] Resumo:Studies on the structural determination, biosynthesis, and biological activities of secondary metabolites from natural sources are significant in the field of natural products chemistry. This review focuses on diverse secondary metabolites isolated from medicinal plants and cultivated mycobionts of lichens in our laboratory. Monoterpene-tetrahydroisoquinoline glycosides and alkaloids isolated from Cephaelis acuminata and Alangium lamarckii gave important information on the biosynthesis of ipecac alkaloids. A variety of glycosides linked with a secologanin unit and indole alkaloids were obtained from medicinal plants belonging to the families of Rubiaceae, Apocynaceae, and Loganiaceae. Plant species of the four genera Fraxinus, Syringa, Jasminum, and Ligustrum of the family Oleaceae were chemically investigated to provide several types of secoiridoid and iridoid glucosides. The biosynthetic pathway leading from protopine to benzophenanthridine alkaloids in suspension cell cultures of Eschscholtzia californica was elucidated. The structures and biological activities of the bisbenzylisoquinoline alkaloids of Stephania cepharantha and Nelumbo nucifera were also investigated. In addition, the mycobionts of lichens were cultivated to afford various types of metabolites that differ from the lichen substances of intact lichens but are structurally similar to fungal metabolites. The biosynthetic origins of some metabolites were also studied. These findings suggest that cultures of lichen mycobionts could be sources of new bioactive compounds and good systems for investigating secondary metabolism in lichens.
[Mh] Termos MeSH primário: Alcaloides/isolamento & purificação
Glicosídeos/isolamento & purificação
Líquens/metabolismo
Plantas Medicinais/metabolismo
[Mh] Termos MeSH secundário: Alangiaceae/metabolismo
Alcaloides/biossíntese
Alcaloides/química
Benzilisoquinolinas
Cephaelis/metabolismo
Eschscholzia/metabolismo
Glicosídeos/biossíntese
Glicosídeos/química
Iridoides
Monoterpenos
Oleaceae/metabolismo
Rubiaceae/metabolismo
Stephania/metabolismo
Tetra-Hidroisoquinolinas
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Nm] Nome de substância:
0 (Alkaloids); 0 (Benzylisoquinolines); 0 (Glycosides); 0 (Iridoids); 0 (Monoterpenes); 0 (Tetrahydroisoquinolines); 56W89FBX3E (1,2,3,4-tetrahydroisoquinoline)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180112
[Lr] Data última revisão:
180112
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171205
[St] Status:MEDLINE
[do] DOI:10.1248/yakushi.17-00147


  6 / 2050 MEDLINE  
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[PMID]:29253026
[Au] Autor:Pino-Bodas R; Laakso I; Stenroos S
[Ad] Endereço:Real Jardín Botánico de Madrid, CSIC, Madrid, Spain.
[Ti] Título:Genetic variation and factors affecting the genetic structure of the lichenicolous fungus Heterocephalacria bachmannii (Filobasidiales, Basidiomycota).
[So] Source:PLoS One;12(12):e0189603, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Heterocephalacria bachmannii is a lichenicolous fungus that takes as hosts numerous lichen species of the genus Cladonia. In the present study we analyze whether the geographical distance, the host species or the host secondary metabolites determine the genetic structure of this parasite. To address the question, populations mainly from the Southern Europe, Southern Finland and the Azores were sampled. The specimens were collected from 20 different host species representing ten chemotypes. Three loci, ITS rDNA, LSU rDNA and mtSSU, were sequenced. The genetic structure was assessed by AMOVA, redundance analyses and Bayesian clustering methods. The results indicated that the host species and the host secondary metabolites are the most influential factors over the genetic structure of this lichenicolous fungus. In addition, the genetic structure of H. bachmannii was compared with that of one of its hosts, Cladonia rangiformis. The population structure of parasite and host were discordant. The contents in phenolic compounds and fatty acids of C. rangiformis were quantified in order to test whether it had some influence on the genetic structure of the species. But no correlation was found with the genetic clusters of H. bachmannii.
[Mh] Termos MeSH primário: Basidiomycota/genética
Variação Genética
Líquens/microbiologia
[Mh] Termos MeSH secundário: Ascomicetos/genética
Teorema de Bayes
DNA Fúngico/genética
DNA Intergênico
Geografia
Haplótipos
Especificidade de Hospedeiro
Interações Hospedeiro-Patógeno
Família Multigênica
Filogenia
Análise de Sequência de DNA
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Fungal); 0 (DNA, Intergenic)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180108
[Lr] Data última revisão:
180108
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171219
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0189603


  7 / 2050 MEDLINE  
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[PMID]:29210244
[Au] Autor:Concostrina-Zubiri L; Huber-Sannwald E; Martínez I; Flores Flores JL; Reyes-Agüero JA; Escude A; Belnap J
[Ti] Título:Biological soil crusts across disturbance­recovery scenarios: effect of grazing regime on community dynamics.
[So] Source:Ecol Appl;24(7):1863-77, 2014.
[Is] ISSN:1051-0761
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Grazing represents one of the most common disturbances in drylands worldwide, affecting both ecosystem structure and functioning. Despite the efforts to understand the nature and magnitude of grazing effects on ecosystem components and processes, contrasting results continue to arise. This is particularly remarkable for the biological soil crust (BSC) communities (i.e., cyanobacteria, lichens, and bryophytes), which play an important role in soil dynamics. Here we evaluated simultaneously the effect of grazing impact on BSC communities (resistance) and recovery after livestock exclusion (resilience) in a semiarid grassland of Central Mexico. In particular, we examined BSC species distribution, species richness, taxonomical group cover (i.e., cyanobacteria, lichen, bryophyte), and composition along a disturbance gradient with different grazing regimes (low, medium, high impact) and along a recovery gradient with differently aged livestock exclosures (short-, medium-, long-term exclusion). Differences in grazing impact and time of recovery from grazing both resulted in slight changes in species richness; however, there were pronounced shifts in species composition and group cover. We found we could distinguish four highly diverse and dynamic BSC species groups: (1) species with high resistance and resilience to grazing, (2) species with high resistance but low resilience, (3) species with low resistance but high resilience, and (4) species with low resistance and resilience. While disturbance resulted in a novel diversity configuration, which may profoundly affect ecosystem functioning, we observed that 10 years of disturbance removal did not lead to the ecosystem structure found after 27 years of recovery. These findings are an important contribution to our understanding of BCS dynamics from a species and community perspective placed in a land use change context.
[Mh] Termos MeSH primário: Bactérias/classificação
Biodiversidade
Recuperação e Remediação Ambiental
Comportamento Alimentar
Líquens/classificação
Microbiologia do Solo
[Mh] Termos MeSH secundário: Animais
México
Modelos Biológicos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180108
[Lr] Data última revisão:
180108
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171207
[St] Status:MEDLINE


  8 / 2050 MEDLINE  
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[PMID]:28829024
[Au] Autor:Kulichevskaya IS; Ivanova AA; Detkova EN; Rijpstra WIC; Sinninghe Damsté JS; Dedysh SN
[Ad] Endereço:1​Winogradsky Institute of Microbiology, Research Center of Biotechnology of the Russian Academy of Sciences, Moscow 119071, Russia.
[Ti] Título:Tundrisphaera lichenicola gen. nov., sp. nov., a psychrotolerant representative of the family Isosphaeraceae from lichen-dominated tundra soils.
[So] Source:Int J Syst Evol Microbiol;67(9):3583-3589, 2017 Sep.
[Is] ISSN:1466-5034
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Two strains of aerobic, budding, pink-pigmented bacteria, P12T and P515, were isolated from a lichen-dominated peatland and a forested tundra soil of north-western Siberia, respectively. Cells of these isolates were represented by non-motile spheres that occurred singly or were arranged in short chains and aggregates. While growing on solid media, cells of strains P12T and P515 attached to the surface by means of holdfast-like appendages. These isolates were mildly acidophilic (optimum growth at pH 5.5-6.0), psychrotolerant bacteria, which displayed tolerance of low temperatures (4-15 °C), grew optimally at 15-22 °C and did not grow at temperatures above 28 °C. The preferred growth substrates were sugars and some heteropolysaccharides. The major fatty acids were C18 : 1ω9c, C16 : 0 and C14 : 0. Trimethylornithine lipid was the major polar lipid. The only quinone was MK-6, and the G+C content of the DNA was 61.2-62.2 mol%. Strains P12T and P515 possessed identical 16S rRNA gene sequences, which affiliated them with the family Isosphaeraceae, order Planctomycetales, and these displayed the highest similarity (93-94 %) to 16S rRNA gene sequences from members of the genus Singulisphaera. However, the signature fatty acid of species of the genus Singulisphaera, i.e. C18 : 2ω6c,12c, was absent in cells of strains P12T and P515. They also differed from members of the genus Singulisphaera by substrate utilization pattern and a number of physiological characteristics. Based on these data, the novel isolates should be considered as representing a novel genus and species of planctomycetes, for which the name Tundrisphaera lichenicola gen. nov., sp. nov, is proposed. The type strain is P12T (=LMG 29571T=VKM B-3044T).
[Mh] Termos MeSH primário: Líquens
Filogenia
Planctomycetales/classificação
Microbiologia do Solo
Tundra
[Mh] Termos MeSH secundário: Técnicas de Tipagem Bacteriana
Composição de Bases
DNA Bacteriano/genética
Ácidos Graxos/química
Planctomycetales/genética
Planctomycetales/isolamento & purificação
RNA Ribossômico 16S/genética
Análise de Sequência de DNA
Sibéria
Vitamina K 2/análogos & derivados
Vitamina K 2/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (DNA, Bacterial); 0 (Fatty Acids); 0 (RNA, Ribosomal, 16S); 11032-49-8 (Vitamin K 2); 71ANL51TLA (menaquinone 6)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170920
[Lr] Data última revisão:
170920
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170823
[St] Status:MEDLINE
[do] DOI:10.1099/ijsem.0.002172


  9 / 2050 MEDLINE  
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[PMID]:28804803
[Au] Autor:Kroukamp EM; Godeto TW; Forbes PBC
[Ad] Endereço:Department of Chemistry, Faculty of Natural and Agricultural Sciences, University of Pretoria, Lynnwood Road, Pretoria, 0002, South Africa.
[Ti] Título:Comparison of sample preparation procedures on metal(loid) fractionation patterns in lichens.
[So] Source:Environ Monit Assess;189(9):451, 2017 Aug 13.
[Is] ISSN:1573-2959
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The effects of different sample preparation strategies and storage on metal(loid) fractionation trends in plant material is largely underresearched. In this study, a bulk sample of lichen Parmotrema austrosinense (Zahlbr.) Hale was analysed for its total extractable metal(loid) content by ICP-MS, and was determined to be adequately homogenous (<5% RSD) for most elements. Several subsets of this sample were prepared utilising a range of sample preservation techniques and subjected to a modified sequential extraction procedure or to total metal extraction. Both experiments were repeated after 1-month storage at 4 °C. Cryogenic freezing gave the best reproducibility for total extractable elemental concentrations between months, indicating this to be the most suitable method of sample preparation in such studies. The combined extraction efficiencies were >82% for As, Cu, Mn, Pb, Sr and Zn but poor for other elements, where sample preparation strategies 'no sample preparation' and 'dried in a desiccator' had the best extraction recoveries. Cryogenic freezing procedures had a significantly (p < 0.05) negative effect on metal extractability, and is therefore inappropriate for sequential extraction procedures in lichens. Biotransformation over a period of a month is suspected for most elements, with the exception of Sr and Zn, where changes in the fractionation patterns were statistically significant (p < 0.05), indicating the need for minimal delay in sample cleaning and preservation when species fractionation patterns are of interest. This study also shows that the assumption that species stability can be ensured through cryopreservation and freeze drying techniques needs to be revisited.
[Mh] Termos MeSH primário: Fracionamento Químico/métodos
Monitoramento Ambiental/métodos
Líquens/química
Metaloides/química
[Mh] Termos MeSH secundário: Metais/análise
Metais/química
Reprodutibilidade dos Testes
Manejo de Espécimes
Análise Espectral
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Metalloids); 0 (Metals)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171020
[Lr] Data última revisão:
171020
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170815
[St] Status:MEDLINE
[do] DOI:10.1007/s10661-017-6155-4


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[PMID]:28736072
[Au] Autor:Sweidan A; Chollet-Krugler M; Sauvager A; van de Weghe P; Chokr A; Bonnaure-Mallet M; Tomasi S; Bousarghin L
[Ad] Endereço:U-1241 INSERM-INRA, Equipe CIMIAD, Univ. Rennes 1, Univ. Bretagne Loire, 2 Avenue du Pr. Léon Bernard, F-35043 Rennes, France; Laboratory of Microbiology, Department of Life and Earth Sciences, Faculty of Sciences I, Lebanese University, Hadath Campus, Beirut, Lebanon.
[Ti] Título:Antibacterial activities of natural lichen compounds against Streptococcus gordonii and Porphyromonas gingivalis.
[So] Source:Fitoterapia;121:164-169, 2017 Sep.
[Is] ISSN:1873-6971
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The oral bacteria not only infect the mouth and reside there, but also travel through the blood and reach distant body organs. If left untreated, the dental biofilm that can cause destructive inflammation in the oral cavity may result in serious medical complications. In dental biofilm, Streptococcus gordonii, a primary oral colonizer, constitutes the platform on which late pathogenic colonizers like Porphyromonas gingivalis, the causative agent of periodontal diseases, will bind. The aim of this study was to determine the antibacterial activity of eleven natural lichen compounds belonging to different chemical families and spanning from linear into cyclic and aromatic structures to uncover new antibiotics which can fight against the oral bacteria. The compounds were screened by broth microdilution assay. Three compounds were shown to have promising antibacterial activities where the depsidone core with certain functional groups constituted the best compound, psoromic acid, with the lowest MICs=11.72 and 5.86µg/mL against S. gordonii and P. gingivalis, respectively. The compounds screened had promising antibacterial activity which might be attributed to some important functional groups as discussed in our study. The best compounds did not induce the death of gingival epithelial carcinoma cells (Ca9-22). These results introduce new compounds having potent antibacterial activities against oral pathogens causing serious medical complications.
[Mh] Termos MeSH primário: Antibacterianos/química
Líquens/química
Porphyromonas gingivalis/efeitos dos fármacos
Streptococcus gordonii/efeitos dos fármacos
[Mh] Termos MeSH secundário: Antibacterianos/isolamento & purificação
Biofilmes/efeitos dos fármacos
Linhagem Celular Tumoral
Seres Humanos
Testes de Sensibilidade Microbiana
Estrutura Molecular
Boca/microbiologia
Doenças Periodontais/microbiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171010
[Lr] Data última revisão:
171010
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170725
[St] Status:MEDLINE



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