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1.
Artigo em Inglês | MEDLINE | ID: mdl-30533757

RESUMO

We report here 32 completed closed genome sequences of strains representing 30 serotypes of Salmonella. These genome sequences will provide useful references for understanding the genetic variation within Salmonella enterica serotypes, particularly as references to aid in comparative genomics studies, as well as providing information for improving in silico serotyping accuracy.

2.
3.
World J Gastrointest Endosc ; 9(9): 471-479, 2017 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-28979712

RESUMO

AIM: To compare colonoscopy quality with nitrous oxide gas (Entonox®) against intravenous conscious sedation using midazolam plus opioid. METHODS: A retrospective analysis was performed on a prospectively held database of 18608 colonoscopies carried out in Lothian health board hospitals between July 2013 and January 2016. The quality of colonoscopies performed with Entonox was compared to intravenous conscious sedation (abbreviated in this article as IVM). Furthermore, the quality of colonoscopies performed with an unmedicated group was compared to IVM. The study used the following key markers of colonoscopy quality: (1) patient comfort scores; (2) caecal intubation rates (CIRs); and (3) polyp detection rates (PDRs). We used binary logistic regression to model the data. RESULTS: There was no difference in the rate of moderate-to-extreme discomfort between the Entonox and IVM groups (17.9% vs 18.8%; OR = 1.06, 95%CI: 0.95-1.18, P = 0.27). Patients in the unmedicated group were less likely to experience moderate-to-extreme discomfort than those in the IVM group (11.4% vs 18.8%; OR = 0.71, 95%CI: 0.60-0.83, P < 0.001). There was no difference in caecal intubation between the Entonox and IVM groups (94.4% vs 93.7%; OR = 1.08, 95%CI: 0.92-1.28, P = 0.34). There was no difference in caecal intubation between the unmedicated and IVM groups (94.2% vs 93.7%; OR = 0.98, 95%CI: 0.79-1.22, P = 0.87). Polyp detection in the Entonox group was not different from IVM group (35.0% vs 33.1%; OR = 1.01, 95%CI: 0.93-1.10, P = 0.79). Polyp detection in the unmedicated group was not significantly different from the IVM group (37.4% vs 33.1%; OR = 0.97, 95%CI: 0.87-1.08, P = 0.60). CONCLUSION: The use of Entonox was not associated with lower colonoscopy quality when compared to intravenous conscious sedation using midazolam plus opioid.

4.
Food Chem ; 198: 125-31, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-26769514

RESUMO

Biorefining aims to exploit the full value of plant material by sequentially extracting and valorising its components. Many studies focus on the saccharification of virgin biomass sources, but it may be more efficient to pre-extract high-value components before hydrolysis to fermentable sugars. In the current study, a bran residue from de-starched, protein depleted and xylanase treated wheat bran has been subjected to hydrothermal pretreatment, saccharification and fermentation procedures to convert the residue to ethanol. The most effective pretreatment conditions (>190 °C, 10 min) and saccharification conditions were identified following bench-scale liquid hot water pretreatment. Pre-extraction of enzymatically-hydrolysable starch and xylan reduced the release of furfural production, particularly when lower pretreatment severities were used. Pilot-scale steam explosion of the lignocellulosic residue followed by cellulase treatment and conversion to ethanol at a high substrate concentration (19%) gave an ethanol titre of ≈ 25 g/L or a yield of 93% of the theoretical maximum.


Assuntos
Amilases/química , Fibras na Dieta/análise , Endo-1,4-beta-Xilanases/química , Etanol/química , Fermentação , Rios
5.
Curr Biol ; 24(20): 2435-9, 2014 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-25283783

RESUMO

Ant-nest beetles (Paussus) are the quintessential Trojan horses of the insect world. They hack the complex communication system of ants, allowing them to blend into the ant society and be treated as royalty, all the while preying upon the ants and the ants' brood and duping the ants into rearing their young. Here we present results of the first molecular-based phylogeny of ant-nest beetles, which reveals that this symbiosis has produced one of the most stunning examples of rapid adaptive radiation documented to date. The most recent ancestor of a Paussus clade endemic to Madagascar is only 2.6 million years old. This species gave rise to a remarkably phenotypically diverse clade of 86 extant species with a net diversification interval of 0.38-0.81 million years, a rate of radiation faster than classic textbook examples of large, recent, rapid radiations such as Anolis lizards on Caribbean islands, cichlids of the East African Great Lakes, finches on the Galápagos Islands, and Drosophila and tetragnathid spiders on the Hawaiian Islands. In order for Paussus to adapt to a new host ant species, the beetle's ability to perceive, deceive, and communicate with the new host must evolve quickly and in synchrony in both the larval and adult life stages, resulting in unusually strong selective pressure levied by their host ants. Data on host associations suggest that the history of host shifts may help explain both the striking phenotypic diversity within the Malagasy radiation and the evolution of phenotypically similar yet distantly related species in Madagascar and Africa.


Assuntos
Adaptação Fisiológica/fisiologia , Formigas/fisiologia , Evolução Biológica , Besouros/anatomia & histologia , Besouros/fisiologia , Distribuição Animal , Animais , Besouros/genética , Fósseis , Comportamento de Nidação
6.
J Agric Food Chem ; 59(20): 11019-25, 2011 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-21894957

RESUMO

The enzymatic hydrolysis of brewers' spent grain (BSG) has been investigated through treatment with commercial carbohydrases and proteases. Resultant residues were then chemically fractionated and delignified. Enzymatic treatments released 25-30% of the BSG mass and yielded precursors suitable for subsequent conversion to potentially value-added products. Controlled chemical fractionation selectively solubilized arabinoxylan but with no differences apparent due to prior enzyme treatment. The loss of non-polysaccharide components during alkali treatment suggests the presence of a high proportion of alkali-soluble lignin. Further delignification of the alkali-insoluble residues and further chemical fractionation released the remaining hemicellulose, to yield a residue which was >90% cellulose. Further knowledge of the properties and interaction between BSG polymers will facilitate an improved enzyme-assisted total deconstruction of BSG and hence the exploitation of its biomass.


Assuntos
Hordeum , Sementes/química , Sementes/metabolismo , Celulose/análise , Celulose/metabolismo , Fracionamento Químico , Glicosídeo Hidrolases/metabolismo , Concentração de Íons de Hidrogênio , Hidrólise , Lignina/análise , Lignina/metabolismo , Peptídeo Hidrolases/metabolismo , Polissacarídeos/análise , Polissacarídeos/metabolismo , Solubilidade
7.
J Agric Food Chem ; 58(12): 7266-72, 2010 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-20509607

RESUMO

The composition of brewers' spent grain (BSG) makes it susceptible to microbial attack and chemical deterioration. This can constrain its appeal as an industrial feedstock. The current study has monitored the effects of BSG storage as fresh material (20 degrees C), refrigerated and autoclaved, measured against frozen material in relation to microbial proliferation and modification to plant cell wall polysaccharides and component phenolic acids. At 20 degrees C there was a rapid colonization by microbes and an associated loss of components from BSG. Refrigeration gave a similar but lower level response. When stored frozen, BSG showed no changes in composition but autoclaving resulted in a solubilization of polysaccharides and associated phenolics. Changes were associated with the temperature profile determined during autoclaving and were also partially due to the breakdown of residual starch. Losses of highly branched arabinoxylan (AX) and the related decrease in ferulic acid cross-linking were also found. The results confirm the need for storage stabilization of BSG and demonstrate that the methods selected for stabilization can themselves lead to a substantial modification to BSG.


Assuntos
Parede Celular/química , Grão Comestível/química , Grão Comestível/microbiologia , Manipulação de Alimentos/métodos , Bactérias/isolamento & purificação , Fenômenos Fisiológicos Bacterianos , Parede Celular/microbiologia , Fungos/isolamento & purificação , Fungos/fisiologia , Temperatura
8.
J Agric Food Chem ; 57(8): 3316-24, 2009 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-19284754

RESUMO

Brewers' spent grain (BSG), a high-volume coproduct from the brewing industry, primarily contains proteins, barley cell wall carbohydrates, and lignin. To create new possibilities for the exploitation of this large biomass stream, the solubilization of BSG by the combined action of carbohydrases (Depol 740 and Econase) and peptidase (Alcalase and Promod 439) was explored. Hydrolysis protocols were optimized with respect to temperature (influencing both microbial contamination and rate of enzymatic hydrolysis), pH, enzyme dose, order of enzyme addition, and processing time. On the basis of this approach, one- and two-step protocols are proposed taking 4-8 h and yielding combined or separate fractions of hydrolyzed oligosaccharides and liberated hydrolyzed protein. Optimized procedures resulted in the solubilization of >80% of the proteinaceous material, up to 39% of the total carbohydrates, and up to 42% of total dry matter in BSG. Of the original xylan present in BSG, 36% could be solubilized. Sequential and simultaneous treatments with the two enzyme types gave similar results. In sequential processes, the order of the carbohydrase and peptidase treatments had only minor effects on the outcome. Depol 740 released more pentoses than Econase and gave slightly higher overall dry matter solubilization yields.


Assuntos
Cerveja , Grão Comestível/química , Glicosídeo Hidrolases/metabolismo , Hordeum/química , Resíduos Industriais , Peptídeo Hidrolases/metabolismo , Hidrólise , Resíduos Industriais/análise , Oligossacarídeos/metabolismo , Proteínas de Plantas/metabolismo , Solubilidade
9.
J Agric Food Chem ; 56(16): 7038-43, 2008 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-18680377

RESUMO

The potential for enzymatic solubilization of brewers' spent grain by carbohydrases and proteases was examined over a broad pH range (pH 3.2-11.2). Enzymes from Trichoderma (Depol 686) were most efficient at a lower pH, while enzymes from the Humicola preparation (Depol 740) were the best performer over the whole range. Profiling of key glycoside hydrolase, esterase and protease activities across the pH range demonstrated that solubilization of spent grain by the Trichoderma enzymes corresponded to the range of maximum activities. This was not the case with the Humicola enzymes, where maximum solubilization of the substrate occurred at pH 9.1, at which pH the determined activities were low. Protease activity in Depol 740 was associated with a high solubilization, but inhibition of proteolytic activity resulted in only a 5% decrease in spent grain solubilization. These results suggest that while enzymes can be used to exploit agro-industrials byproduct, the use of high pH increases the extent of hydrolysis and an unidentified factor produced by Humicola improves the enzyme-catalyzed solubilization of lignocellulosic material.


Assuntos
Grão Comestível/metabolismo , Glicosídeo Hidrolases/metabolismo , Peptídeo Hidrolases/metabolismo , Ascomicetos/enzimologia , Cerveja , Esterases/metabolismo , Concentração de Íons de Hidrogênio , Resíduos Industriais , Solubilidade , Trichoderma/enzimologia
10.
J Agric Food Chem ; 56(5): 1720-6, 2008 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-18251503

RESUMO

Analysis of wheat bran and spent grain shows that concentrations of ferulate and diferulates offer considerable scope to modify the cross-linking of feruloylated polysaccharides and hence the mechanical properties of these residues. In solution ferulic acid (FA) can be readily polymerized by horseradish peroxidase, but when esterified to a polysaccharide, the profile of diferulates becomes restricted. This situation also exists in muro and suggests structural constraints may limit the availability of FA for cross-linking. At relatively low polysaccharide concentration, (approximately 3%), steric restrictions were apparent in gels prepared using isolated polysaccharides. Mechanical properties such as swelling also appear to be fixed at these relatively low polysaccharide concentrations. This limits the potential to modify mechanical properties in muro through oxidoreductase activity. To modify mechanical properties such treatments will need to focus on increasing the "flexibility" of the cell wall matrix and the accessibility of enzymes to the cell wall matrix.


Assuntos
Parede Celular/enzimologia , Ácidos Cumáricos/metabolismo , Fibras na Dieta/metabolismo , Peroxidase do Rábano Silvestre/metabolismo , Triticum , Parede Celular/fisiologia , Ácidos Cumáricos/química , Fibras na Dieta/análise , Peróxido de Hidrogênio , Oxirredução , Polissacarídeos/química , Polissacarídeos/metabolismo , Solubilidade , Triticum/química , Triticum/metabolismo
11.
Mol Phylogenet Evol ; 46(1): 193-205, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17988897

RESUMO

Phylogenetic relationships within the diverse beetle superfamily Cucujoidea are poorly known. The Cerylonid Series (C.S.) is the largest of all proposed superfamilial cucujoid groups, comprising eight families and representing most of the known cucujoid species diversity. The monophyly of the C.S., however, has never been formally tested and the higher-level relationships among and within the constituent families remain equivocal. Here we present a phylogenetic study based on 18S and 28S rDNA for 16 outgroup taxa and 61 C.S. ingroup taxa, representing seven of the eight C.S. families and 20 of 39 subfamilies. We test the monophyly of the C.S., investigate the relationships among the C.S. families, and test the monophyly of the constituent families and subfamilies. Phylogenetic reconstruction of the combined data was achieved via standard static alignment parsimony analyses, Direct Optimization using parsimony, and partitioned Bayesian analysis. All three analyses support the paraphyly of Cucujoidea with respect to Tenebrionoidea and confirm the monophyly of the C.S. The C.S. families Bothrideridae, Cerylonidae, Discolomatidae, Coccinellidae and Corylophidae are supported as monophyletic in all analyses. Only the Bayesian analysis recovers a monophyletic Latridiidae. Endomychidae is recovered as polyphyletic in all analyses. Of the 14 subfamilies with multiple terminals in this study, 11 were supported as monophyletic. The corylophid subfamily Corylophinae and the coccinellid subfamilies Chilocorinae and Scymninae are recovered as paraphyletic. A sister grouping of Anamorphinae+Corylophidae is supported in all analyses. Other taxonomic implications are discussed in light of our results.


Assuntos
Besouros/classificação , Animais , Besouros/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Filogenia , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , Análise de Sequência de DNA
12.
Proteomics ; 5(6): 1612-23, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15789342

RESUMO

Proteomic methods have been used to identify foam-forming soluble proteins from dough that may play an important role in stabilising gas bubbles in dough, and hence influence the crumb structure of bread. Proteins from a soluble fraction of dough (dough liquor) or dough liquor foam have been separated by two-dimensional gel electrophoresis, and 42 identified using a combination of matrix-assisted laser desorption/ionization-time of flight and quadrupole-time of flight analyses. Major polypeptide components included beta-amylase, tritin and serpins, with members of the alpha-amylase/trypsin inhibitor family being particularly abundant. Neither prolamin seed storage proteins nor the surface-active protein puroindoline were found. Commonly used dough ingredients (NaCl, Na L-ascorbate) had only a minor effect on the 2-DE protein profiles of dough liquor, of which one of the more significant was the loss of 9 kDa nonspecific lipid transfer protein. Many proteins were lost in dough liquor foam, particularly tritin, whilst a number of alpha-amylase inhibitors were more dominant, suggesting that these are amongst the most strongly surface-active proteins in dough liquor. Such proteins may play a role determining the ability of the aqueous phase of doughs, as represented by dough liquor, to form an elastic interface lining the bubbles, and hence maintain their integrity during dough proving.


Assuntos
Pão , Proteínas de Plantas/metabolismo , Tensoativos/metabolismo , Triticum/metabolismo , Ácido Ascórbico , Eletroforese em Gel Bidimensional , Proteômica , Cloreto de Sódio , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
13.
Magn Reson Chem ; 43(6): 457-62, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15736151

RESUMO

The spin probes 1,1,3,3-tetramethylisoindolin-2-yloxyl (TMIO) and the sodium salt of its sulfonate, 1,1,3,3-tetramethylisoindolin-2-yloxyl-5-sulfonate (NaTMIOS) were used to monitor the microviscosity changes of water during starch gelatinization. In cereal starch, which contains mainly A-type polymorphs, evidence was found for the amylopectin and amylose regions, the latter undergoing a transition at about 55 degrees C and a large increase in the microviscosity on cooling. Pea starch contains both A-and B-type polymorphs and this was also found to have two domains and the 55 degrees C transition was observed for the amylose phase: the less mobile amylopectin showed a reversible decrease in water microviscosity on heating.


Assuntos
Óxidos N-Cíclicos/química , Géis/química , Indóis/química , Marcadores de Spin , Amido/química , Ácidos Sulfônicos/química , Espectroscopia de Ressonância de Spin Eletrônica/instrumentação , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Temperatura Alta , Reologia , Temperatura , Viscosidade , Água/química
15.
Biochim Biophys Acta ; 1698(2): 175-86, 2004 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-15134650

RESUMO

Proteomic approaches have been used to characterise the main 2S albumin isoforms from Brazil nuts (Bertholletia excelsa). Whilst most isoforms ( approximately 10 discrete protein species) exhibited molecular masses of around 12 kDa with a high amino acid sequence homology, important charge heterogeneity was found, with pIs varying between 4.6 and 6.6, with one >or=7.0. Proteomic analysis showed that these corresponded to a total of six National Center for Biotechnology Information (NCBI) accessions and that three isoforms had been purified to homogeneity corresponding to gi/384327, 112754 and 99609. The latter sequence corresponds to an isoform, previously only identified at the nucleotide sequence level, had a slightly higher molecular weight (13.4 kDa), and with noticeable differences in the primary structure. Proteins corresponding to six different NCBI accessions were identified, the heterogeneity of which had been increased by posttranslational processing. Evidence was found of cyclization of the N-terminal glutamine residue in two isoforms, together with ragged C-termini, indicative of carboxypeptidase activity within the vacuole following posttranslational processing. No evidence of glycosylation was found. Circular dichroism (CD) and Fourier transform-infrared (FT-IR) spectroscopy indicated all the studied isoforms were predominantly alpha-helical in nature, but that the Mr 13400 species was structurally distinct, with a higher proportion of alpha-helical structure.


Assuntos
Albuminas/química , Bertholletia/química , Precursores de Proteínas/química , Albuminas 2S de Plantas , Albuminas/genética , Albuminas/isolamento & purificação , Sequência de Aminoácidos , Antígenos de Plantas , Bertholletia/genética , Dicroísmo Circular , Eletroforese em Gel de Poliacrilamida , Variação Genética , Espectrometria de Massas , Dados de Sequência Molecular , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Precursores de Proteínas/genética , Precursores de Proteínas/isolamento & purificação , Estrutura Secundária de Proteína , Espectroscopia de Infravermelho com Transformada de Fourier
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