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1.
Mol Ecol ; 32(15): 4381-4400, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37211644

RESUMO

Xylosandrus crassiusculus, a fungus-farming wood borer native to Southeastern Asia, is the most rapidly spreading invasive ambrosia species worldwide. Previous studies focusing on its genetic structure suggested the existence of cryptic genetic variation in this species. Yet, these studies used different genetic markers, focused on different geographical areas and did not include Europe. Our first goal was to determine the worldwide genetic structure of this species based on both mitochondrial and genomic markers. Our second goal was to study X. crassiusculus' invasion history on a global level and identify the origins of the invasion in Europe. We used a COI and RAD sequencing design to characterize 188 and 206 specimens worldwide, building the most comprehensive genetic data set for any ambrosia beetle to date. The results were largely consistent between markers. Two differentiated genetic clusters were invasive, albeit in different regions of the world. The markers were inconsistent only for a few specimens found exclusively in Japan. Mainland USA could have acted as a source for further expansion to Canada and Argentina through stepping stone expansion and bridgehead events. We showed that Europe was only colonized by Cluster II through a complex invasion history including several arrivals from multiple origins in the native area, and possibly including bridgehead from the United States. Our results also suggested that Spain was colonized directly from Italy through intracontinental dispersion. It is unclear whether the mutually exclusive allopatric distribution of the two clusters is due to neutral effects or due to different ecological requirements.


Assuntos
Besouros , Gorgulhos , Animais , Besouros/genética , Ambrosia/genética , Metagenômica , Europa (Continente) , Espécies Introduzidas
2.
Heliyon ; 10(9): e29662, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38694124

RESUMO

The gelatinisation temperature and bimodal granule size distribution of barley starch are important characteristics regarding resource efficiency and product quality in the brewing industry. In this work, the diversity in starch amylose content and granule proportions in a set of modern barley varieties (N = 23) was investigated and correlated with their starch gelatinisation behaviour. Milled barley samples had peak starch gelatinisation temperatures ranging from 60.1 to 66.5 °C. Upon separating the barley starch from the non-starch compounds, sample-dependent decreases in starch gelatinisation temperatures were observed, indicating the importance of differences in barley composition. The peak gelatinisation temperatures of milled barley and isolated barley starches were strongly correlated (r = 0.96), indicating that the behaviour of the starch population is strongly reflected in the measurements performed on milled barley. Therefore, we investigated whether amylose content or starch granule size distribution could predict the gelatinisation behaviour of the starches. Broad ranges in the small starch granule volumes (13.9-32.0 v/v%) and amylose contents (18.2-30.7 w/w%) of the barley starches were observed. For the barley samples collected in the north of the USA (N = 8), the small starch granule volumes correlated positively with the peak gelatinisation temperatures of barley starches (r = 0.90, p < 0.01). The considerable variation in starch properties described in this work highlights that, besides starch content, starch gelatinisation temperature or granule size distribution might provide brewers with useful information to optimise resource efficiency.

3.
Food Res Int ; 167: 112653, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37087242

RESUMO

We studied the impact of malting on barley starch gelatinisation properties and whether observed differences are due to changes in extrinsic or intrinsic factors. We isolated the total starch and large and small starch granules fractions from barley and malt samples and subjected them to DSC. The peak gelatinisation temperature for malt starch was, on average, 1.2 °C higher than for barley starch. The malting process and endosperm breakdown products were each responsible for half of this difference. The presence of water-extractable, non-starch components (sugars, minerals, protein and starch hydrolysis products,…) increased the intrinsic starch gelatinisation temperatures by 2.2-4.7 °C for barley and 3.6-5.3 °C for malt. The small starch granule fractions from barley had a 3.1 °C higher peak gelatinisation temperature than large granule fractions. No effect of malting was observed here. These findings indicate that matrix effects and starch granule size must be considered when addressing starch conversion during brewing.


Assuntos
Hordeum , Amido , Amido/metabolismo , Hidrólise , Temperatura , Açúcares/metabolismo
4.
Carbohydr Polym ; 306: 120597, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36746587

RESUMO

The impact of arabinoxylan (AX) on the brewing process and beer characteristics depends on its content and structure and is often overlooked in research and industry. This paper reports on the occurrence and structural heterogeneity of AX in a set of commercial pilsner beers and their non-alcoholic counterparts. Fractionation by graded ethanol precipitation allowed us to isolate AX-rich fractions from beer with a number-average degree of polymerisation of 4 to 308 and an average degree of substitution in the range of 0.43 to 0.88. Pilsner beers had a higher content of high-molecular-weight AX than their non-alcoholic counterparts. The structural heterogeneity among the various commercial beers differed. By comparing the chemical composition of the beers, differences in beer production methods and ingredient selection were deduced and used to tentatively explain the differences in AX content and structural heterogeneity.


Assuntos
Cerveja , Xilanos , Cerveja/análise , Xilanos/química , Etanol , Peso Molecular
5.
Int J Bipolar Disord ; 11(1): 16, 2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37119343

RESUMO

BACKGROUND: Response to lithium (Li) is highly variable in bipolar disorders (BD). Despite decades of research, no clinical predictor(s) of response to Li prophylaxis have been consistently identified. Recently, we developed epigenetic Methylation Specific High-Resolution Melting (MS-HRM) assays able to discriminate good responders (GR) from non-responders (NR) to Li in individuals with BD type 1 (BD-I). This study examined whether a combination of clinical and epigenetic markers can distinguish NR from other types of Li responders. METHODS: We recorded clinical variables that are potentially associated with Li response in 64 individuals with BD-I. MS-HRM assays were performed on DNA isolated from peripheral blood. We used backward stepwise logistic regression analyses, followed by receiver operating characteristic (ROC) curve analysis to estimate the performance of the clinical variables, alone then in combination with the epigenetic biomarkers, to identify GR and partial responders (PaR) vs NR. RESULTS: Polarity at onset, psychotic symptoms at onset and family history of BD classified correctly 70% of individuals according to their Li response (PaR + GR = 86%; NR = 35%). When combined with the epigenetic biomarkers, these three clinical variables plus alcohol misuse (and one DMR: Differentially Methylated Region) correctly classified 86% of individuals, improving the prediction of PaR + GR (93%) and of NR (70%). The ROC analysis demonstrated an improvement in the area under the curve from 0.75 (clinical variables alone) to 0.87 (combination of clinical and epigenetic markers). CONCLUSIONS: Combining clinical predictors and DNA methylation markers of Li response may have greater utility in clinical practice than relying on clinical characteristics alone.

6.
Mol Ecol ; 21(24): 6086-103, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23110419

RESUMO

Most invasive species established in Europe originate from either Asia or North America, but little is currently known about the potential of the Anatolian Peninsula (Asia Minor) and/or the Near East to constitute invasion sources. Mediterranean forests are generally fragile ecosystems that can be threatened by invasive organisms coming from different regions of the Mediterranean Basin, but for which historical data are difficult to gather and the phylogeographic patterns are still poorly understood for most terrestrial organisms. In this study, we characterized the genetic structure of Megastigmus schimitscheki, an invasive seed-feeding insect species originating from the Near East, and elucidated its invasion route in South-eastern France in the mid 1990s. To disentangle the evolutionary history of this introduction, we gathered samples from the main native regions (Taurus Mountains in Turkey, Lebanon and Cyprus) and from the invaded region that we genotyped using five microsatellite markers and for which we sequenced the mitochondrial Cytochrome Oxidase I gene. We applied a set of population genetic statistics and methods, including approximate Bayesian computation. We proposed a detailed phylogeographic pattern for the Near East populations, and we unambiguously showed that the French invasive populations originated from Cyprus, although the available historical data strongly suggested that Turkey could be the most plausible source area. Interestingly, we could show that the introduced populations were founded from an extremely restricted number of individuals that realized a host switch from Cedrus brevifolia to C. atlantica. Evolutionary hypotheses are discussed to account for this unlikely scenario.


Assuntos
Efeito Fundador , Genética Populacional , Vespas/genética , Animais , Teorema de Bayes , Chipre , DNA Mitocondrial/genética , Evolução Molecular , França , Variação Genética , Espécies Introduzidas , Repetições de Microssatélites , Dados de Sequência Molecular , Filogeografia , Análise de Sequência de DNA
8.
Food Res Int ; 157: 111201, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35761523

RESUMO

To obtain an efficient conversion of starch into fermentable sugars and dextrins during the brewing process, mashing time-temperature profiles need to promote starch gelatinisation and enzyme activity while avoiding thermal inactivation of the amylases. This study focused on the second part of this balance by investigating the thermal stability of α-amylase and ß-amylase of Planet barley malt throughout mashing. Thermal inactivation in wort was modelled for both enzymes resulting in the estimation of thermal inactivation kinetic parameters such as rate constant of thermal inactivation kT (the rate of thermal inactivation of an enzyme at a constant temperature), activation energy for thermal inactivation Ea, decimal reduction time DT (the time needed to inactivate 90% of the enzyme activity at a given temperature) and the z-value. First-order inactivation was observed for α-amylase. For ß-amylase, fractional conversion inactivation occurred with a residual fraction of 13% of the ß-amylase activity that remained after prolonged heating at 72.5 °C. The ß-amylase protein population hence seems to consist of thermolabile and thermostable isoforms. The kinetic parameters for thermal inactivation of the enzymes were used to predict their residual activities throughout a laboratory-scale mashing process. The predicted residual activities met the experimentally determined residual enzyme activities closely, except for ß-amylase at temperatures higher than 72.5 °C. The results obtained in this work allow designing new mashing processes or tailoring existing processes towards variability in the input material, barley malt, without the need for trial-and-error experiments.


Assuntos
Hordeum , beta-Amilase , Amilases/metabolismo , Amido/metabolismo , alfa-Amilases/metabolismo , beta-Amilase/metabolismo
9.
Insect Mol Biol ; 20(2): 267-78, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21205278

RESUMO

Three genes encoding proteins showing sequence similarity and features typical of insect APNs were characterized in C. tremulae and designed as CtAPN1, CtAPN2 and CtAPN3. Expression analysis of the three C. tremulae APN genes showed that CtAPN2 transcript is more abundant in the fat body, whereas both CtAPN1 and CtAPN3 are specifically expressed in the midgut. Despite a similar genomic organization, lepidopteran and coleopteran APNs are phylogenetically distant, suggesting that APN gene duplication events occurred after these two insect orders split. Sequence and expression comparisons of CtAPN1, CtAPN2 and CtAPN3 cDNAs in a C. tremulae Bacillus thuringiensis (Bt)-susceptible and in a Bt-resistant strain did not show any polymorphism at the amino acid level or difference at the transcription level.


Assuntos
Proteínas de Bactérias , Antígenos CD13/genética , Besouros/enzimologia , Besouros/genética , Endotoxinas , Proteínas Hemolisinas , Controle Biológico de Vetores , Sequência de Aminoácidos , Animais , Bacillus thuringiensis/genética , Toxinas de Bacillus thuringiensis , Sistema Digestório/enzimologia , Corpo Adiposo/enzimologia , Feminino , Perfilação da Expressão Gênica , Estágios do Ciclo de Vida , Filogenia , Plantas Geneticamente Modificadas/genética , Populus/genética , Alinhamento de Sequência , Tribolium/genética
10.
EFORT Open Rev ; 6(12): 1166-1180, 2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-35767431

RESUMO

To report clinical and radiographic outcomes of primary THA using three-dimensional (3D) image-based custom stems. This systematic review was performed according to PRISMA guidelines and registered with PROSPERO (CRD42020216079). A search was conducted using MEDLINE, Embase and Cochrane. Clinical studies were included if they reported clinical or radiographic outcomes of primary THA using 3D image-based custom stems. Studies were excluded if specific to patients with major hip anatomical deformities, or if not written in English. Fourteen studies were eligible for inclusion (n = 1936 hips). There was considerable heterogeneity in terms of manufacturer, proximal geometry, coating and length of custom stems. Revision rates ranged from 0% to 1% in the short-term, 0% to 20% in the mid-term, and 4% to 10% in the long-term, while complication rates ranged from 3% in the short-term, 0% to 11% in the mid-term and 0% to 4% in the long-term. Post-operative Harris hip scores ranged from 95 to 96 in the short-term, 80 to 99 in the mid-term, and 87 to 94 in the long-term. Radiographic outcomes were reported in eleven studies, although none reported 3D implant sizing or positioning, nor compared planned and postoperative hip architecture. Primary THA using 3D image-based custom stems in unselected patients provides limited but promising clinical and radiographic outcomes. Despite excellent survival, the evidence available in the literature remains insufficient to recommend their routine use. Future studies should specify proximal geometry, length, fixation, material and coating, as well as management of femoral offset and anteversion. The authors propose a classification system to help distinguish between custom stem designs based primarily on their proximal geometry and length.

11.
Carbohydr Polym ; 255: 117494, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33436252

RESUMO

Hydrolysis of starch is key in several industrial processes, including brewing. Here, the activity and inactivation kinetics of amylases throughout barley malt mashing are investigated, as a prerequisite for rational optimisation of this process. Varietal differences were observed in the activity of α- and ß-amylases as a function of temperature for six barley and malt varieties. These differences were not reflected in the resulting wort composition after mashing, using three isothermal phases of 30 min at 45 °C, 62 °C and 72 °C with intermediate heating by 1 °C/min. Thermal inactivation kinetics parameters determined for α- and ß-amylases of an industrially relevant malt variety in a diluted system showed that enzymes were inactivated at lower temperatures than expected. The obtained kinetic parameters could predict α-amylase, but not ß-amylase inactivation in real mashing conditions, suggesting that ß-amylase stability is enhanced during mashing by components present or formed in the mash.


Assuntos
Hordeum/enzimologia , Proteínas de Plantas/metabolismo , Plântula/enzimologia , Amido/metabolismo , alfa-Amilases/metabolismo , beta-Amilase/metabolismo , Cerveja , Ensaios Enzimáticos , Estabilidade Enzimática , Fermentação , Hordeum/química , Temperatura Alta , Humanos , Hidrólise , Cinética , Proteínas de Plantas/química , Plântula/química , Amido/química , alfa-Amilases/química , beta-Amilase/química
12.
Malays Orthop J ; 14(3): 82-89, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33403066

RESUMO

INTRODUCTION: Diabetic foot ulcer is the main aetiology for non-traumatic amputation, which is a major public health care concern. A multidisciplinary approach in the management of this pathology has been shown to improve the surgical outcome. However, there are little data available on the tools we can use to pursue this multidisciplinary approach. The main goal of this cross-sectional study was to find out whether the implementation of a specific management pathway could improve the treatment outcome in the treatment of diabetic foot. MATERIALS AND METHODS: From 2012 to 2014, we consecutively recruited patients with diabetic foot referred to Orthopaedic surgery department of our university for surgical opinion. A specific diabetic foot pathway was introduced in 2013. One group of patients who were treated with previous method were evaluated retrospectively. Another group of patients who were treated after implementation of the pathway were evaluated prospectively. We compared treatment outcome between the two groups. RESULTS: We included 51 patients. Amputation rate was similar both the groups: 74% in the retrospective group not using the new pathway versus 73% in a prospective group that used the new pathway. Revision surgery was 39% in the retrospective group and 14% in the prospective group (p=0.05). CONCLUSION: We recommend the use of this simple and cost-effective pathway to guide the interdisciplinary management of diabetic foot. A prospective study with more subjects would provide a better overview of this management pathway.

13.
Poult Sci ; 99(5): 2555-2565, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32359591

RESUMO

While arabinoxylans (AX), an important dietary fiber fraction of wheat-based broiler diets, are known for exerting antinutritional effects in the gastrointestinal (GI) tract of broilers, the prebiotic potential of arabinoxylan-oligosaccharides (AXOS) is also well-documented. However, inconsistent performance responses as well as the effectiveness of low amounts of AXOS used in diets of previously conducted experiments put into question the classical prebiotic route being the sole mode of action of AXOS. The objective of this study was to investigate the effects of dietary AXOS addition on the rate of AX digestion in the gastrointestinal tract of broilers as a function of broiler age to gain more insight into the mode of action of these oligosaccharides. A feeding trial was performed on 480 one-day-old chicks (Ross 308) receiving a wheat-based diet supplemented with or without 0.50% AXOS, containing no endoxylanases. Digesta samples from ileum and caeca and fecal samples were analyzed for AX content, AX digestibility, intestinal viscosity, and microbial AX-degrading enzyme activities at 6 different ages (day 5, 10, 15, 21, 28, 35). Chicks fed from hatching with 0.50% AXOS demonstrated a higher ileal viscosity (P < 0.05). Also higher levels of AX solubilization and fermentation compared to control birds at 10 D were observed. This was noted by the higher total tract AX digestibility of water-extractable AX (WE-AX) and total AX (TOT-AX) at this age (P < 0.05). Although no significant difference in AX-degrading enzyme activities was observed among the dietary treatments, AXOS supplementation in young broilers was shown to stimulate or "kick-start" dietary AX digestion, thereby speeding up the development of a fiber-fermenting microbiome in the young broiler. This stimulation effect of AXOS could enable greater functional value to be extracted from dietary fiber in broiler feeds.


Assuntos
Galinhas/fisiologia , Digestão , Endo-1,4-beta-Xilanases/metabolismo , Oligossacarídeos/metabolismo , Xilanos/metabolismo , Envelhecimento , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Suplementos Nutricionais/análise , Masculino , Oligossacarídeos/administração & dosagem , Distribuição Aleatória , Xilanos/administração & dosagem
14.
Carbohydr Polym ; 227: 115329, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31590877

RESUMO

The proportion of small and large starch granules in barley and malt is often neglected, leading to underestimation of their importance in processes in which they are used. This study aimed to accurately determine the volume and number based percentages of small and large starch granules for three barley varieties, their micro-malted malts and three commercial malts. Quantitative starch isolation was performed and starch granule proportions were estimated using microscopic and image analysis, taking the non-sphericity of the large starch granules into account. Results show that barley starch consists of 32-39 volume% of small starch granules. Upon malting, this percentage is reduced to 17-27 volume%, showing that small granules are hydrolyzed faster than large granules during this process. The analyzed commercial malt samples have a small starch granule content of 22-25 volume%. Malt hence still contains a substantial amount of small starch granules, which can be expected to impact processing.


Assuntos
Hordeum/química , Amido/química , Tamanho da Partícula
15.
Psychoneuroendocrinology ; 120: 104753, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32634746

RESUMO

INTRODUCTION: Bipolar disorder (BD) is highly associated with childhood maltreatment (CM), the exposure to such early adversity being suggested to disrupt the expression of several biological pathways. This study aims at exploring associations between the mRNA levels of 9 HPA axis genes in lymphoblastoid cell lines from patients with BD according to their self-reported exposure to CM. METHODS: The sample consisted of 33 Caucasian patients with a diagnosis of BD type 1, assessed for the exposure to CM with the Childhood Trauma Questionnaire (CTQ). Quantitative RT-PCR was performed on 9 transcripts of the HPA axis genes: DGKH, FKBP5, NR3C1, SGK1, SGK2, SGK3, SKA2, STAT5A and UCN. RT-qPCR data were analyzed using the method of disjoint gene networks with SARP.compo package for R. RESULTS: We found no associations between CTQ total score and the amount of HPA axis transcripts neither in univariate analyses, nor with network analyses. Emotional abuse (EA) was associated with a significant decreased expression of two transcripts, DGKH (p = 0.009) and NR3C1 (p = 0.04). This was confirmed by the disjoint network analysis, which showed that NR3C1 and DGKH were expressed differently from the rest of the HPA axis network in presence of emotional abuse. DISCUSSION: This study described the expression levels of a comprehensive set of HPA axis genes according to childhood maltreatment in a sample of patients with BD type 1 and suggested that emotional abuse decreased the expression of NR3C1 and DGKH. Our results require further replication in independent larger samples.


Assuntos
Experiências Adversas da Infância/psicologia , Transtorno Bipolar/genética , Redes Reguladoras de Genes/genética , Adulto , Transtorno Bipolar/metabolismo , Diacilglicerol Quinase/genética , Diacilglicerol Quinase/metabolismo , Feminino , Expressão Gênica/genética , Humanos , Sistema Hipotálamo-Hipofisário/metabolismo , Linfócitos/metabolismo , Masculino , Pessoa de Meia-Idade , Sistema Hipófise-Suprarrenal/metabolismo , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo
16.
J Appl Microbiol ; 106(3): 932-40, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19191975

RESUMO

AIMS: To search for nondigestible but fermentable (NDF) carbohydrates and prebiotics with a potency to promote the growth of selected bacteria in vitro. METHODS AND RESULTS: The growth of three reference bacteria strains Bacillus subtilis LMG 7135(T), Carnobacterium piscicola LMG 9839, Lactobacillus plantarum LMG 9211 and one candidate probiotic bacteria Lactobacillus delbrueckii subsp. lactis was investigated over a minimum period of 48 h in the presence of beta-glucan, xylo-oligosaccharide, arabinoxylo-oligosaccharide, inulin, oligofructose and glucose. Besides the capability to grow on inulin and oligofructose containing media, a distinct high growth in beta-glucan based substrates and a low growth in (arabino)xylooligosaccharide containing media were evident for most bacteria tested. With the exception of B. subtilis and L. plantarum, other bacteria grew equally well or even better on different substrates than on glucose. The fermentation of studied carbohydrates by these micro-organisms was dominated by the production of acetic acid as the main short chain fatty acid. CONCLUSIONS: Selected bacteria are able to ferment and grow on NDF and prebiotic carbohydrates but in a substrate dependent manner. SIGNIFICANCE AND IMPACT OF THE STUDY: This study delivers a first screening of which NDF or prebiotic carbohydrates are the most promising for aquaculture feed supplementations.


Assuntos
Bactérias/crescimento & desenvolvimento , Metabolismo dos Carboidratos , Prebióticos , Probióticos , Ácido Acético/metabolismo , Animais , Bacillus subtilis/crescimento & desenvolvimento , Bactérias/metabolismo , Técnicas Bacteriológicas , Carnobacterium/crescimento & desenvolvimento , Contagem de Colônia Microbiana , Meios de Cultura , Peixes/microbiologia , Glucose/metabolismo , Inulina/metabolismo , Lactobacillus/crescimento & desenvolvimento , Oligossacarídeos/metabolismo , beta-Glucanas/metabolismo
17.
Poult Sci ; 98(10): 4606-4621, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30993340

RESUMO

Endoxylanases are frequently used in cereal-based broiler feeds to improve the nutritional quality of the feed. It is hypothesized that the age of broilers and the age-related development of their intestinal microbiota influence the efficacy of these enzymes. Hence, the objective of this study was to identify possible age-related changes in arabinoxylan (AX) digestion in the different parts of the gastrointestinal (GI) tract of broilers. A feeding trial was performed with 240 1-day-old chicks (Ross 308) receiving a wheat-based feed containing no supplemented endoxylanase. Digesta samples from every section of the GI tract were collected at 5, 10, 15, 21, 28, and 35 d of age and analyzed for AX content, AX digestibility, intestinal viscosity, and microbial endoxylanase and arabinofuranosidase activities. In the first 2 wk, the microbiota were able to solubilize a part of the water-unextractable arabinoxylan (WU-AX), thereby increasing intestinal viscosity and water-extractable arabinoxylan (WE-AX) concentrations in the GI tract. In these young birds, WU-AX and WE-AX with low arabinose to xylose ratios were able to enter the caeca but were not yet extensively fermented by the caecal microbiota as indicated by the high caecal AX concentrations at 5 and 10 d (P < 0.01). Establishment of a more mature microbial community at 3 wk of age resulted in a further increase in both the solubilization of WU-AX and fermentation of WE-AX at the ileum and caecum (P < 0.10). Furthermore, the increase in AX degrading enzyme activities with age denotes the high AX degrading capacity of the caecal microbiota. Finally, a total tract AX digestion of 24% was achieved at slaughter age (day 35). Our results clearly indicate that the capacity of intestinal microbiota to degrade AX in the hindgut increases as the broiler ages. This suggests that the benefits of endoxylanase supplementation of broiler feeds depend on the interaction of the intestinal microbiota and AX present in the GI tract at specific broiler ages.


Assuntos
Galinhas/fisiologia , Dieta/veterinária , Digestão/fisiologia , Xilanos/metabolismo , Fatores Etários , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Galinhas/crescimento & desenvolvimento , Fermentação , Trato Gastrointestinal/metabolismo , Hidrólise , Xilanos/administração & dosagem
18.
Poult Sci ; 87(11): 2329-34, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18931184

RESUMO

The objective of this in vivo experiment was to evaluate the influence of arabinoxylooligosaccharides (AXOS) on shedding and colonization of Salmonella Enteritidis in broilers. Arabinoxylooligosaccharides, which are oligosaccharides derived from arabinoxylans by partial hydrolysis, have a beneficial effect on feed conversion ratios when added to broiler diets. Additionally, AXOS have been shown to promote the growth of bifidobacteria in the cecocolonic compartment of the gastrointestinal tract. To investigate the impact of AXOS on colonization of broilers with Salmonella, 224 one-day-old chicks were divided into 4 groups and given either unsupplemented feed or feed supplemented with 0.2% AXOS-3-0.25, 0.2% AXOS-9-0.25, or 0.4% AXOS-9-0.25 throughout the experiment. The AXOS-3-0.25 and AXOS-9-0.25 both have an ara-binose-to-xylose ratio of 0.25 and have an average degree of polymerization of 3 and 9, respectively. At 14 d posthatch, each animal was orally inoculated with 2.5 x 10(9) cfu of Salmonella Enteritidis. Cloacal swabs, taken at regular times, showed a significant reduction of Salmonella presence in the group given 0.4% AXOS-9-0.25 compared with the control group. This reduction was observed in the 1- to 11-d postinfection period. Colonization of the ceca as well as the translocation of Salmonella to the spleen was significantly reduced at 3 and 7 d postinfection in the 0.4% AXOS-9-0.25 group. A similar, although more moderate, decrease in colonization was observed in the group given 0.2% AXOS-9-0.25. It was concluded that dietary addition of AXOS provides dose-dependent protection against oral infections with Salmonella Enteritidis in poultry.


Assuntos
Galinhas/microbiologia , Oligossacarídeos/uso terapêutico , Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/prevenção & controle , Salmonella enteritidis/efeitos dos fármacos , Salmonella enteritidis/crescimento & desenvolvimento , Xilanos/uso terapêutico , Ração Animal , Animais , Encéfalo , Cloaca/efeitos dos fármacos , Cloaca/microbiologia , Digestão/efeitos dos fármacos , Digestão/fisiologia , Oligossacarídeos/isolamento & purificação , Doenças das Aves Domésticas/prevenção & controle , Triticum , Xilanos/isolamento & purificação
19.
Food Chem ; 253: 262-268, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29502830

RESUMO

This study investigates the effect of the physical presence and water binding of wheat bran during bread making, and the possible mechanisms behind this effect. Regular bran, pericarp-enriched bran and synthetic bran-like particles with different water binding capacities and particle sizes were used. Incorporation of regular and pericarp-enriched bran in dough (15% dm) led to a lower oven rise than the control dough. Bread volumes decreased with 11% and 30%, respectively. Dough with synthetic bran, having a low water binding capacity, displayed a near to normal leavening and oven rise and resulted in a bread volume decrease of only 5% compared to the control. Particle size reduction of regular bran and synthetic bran to an average size of 200 µm did not affect final bread quality. Results indicate that water binding by bran affects bread quality the most, whereas steric hindrance by physical presence of bran particles is less determinative.


Assuntos
Pão , Fibras na Dieta , Água/química , Farinha/análise , Tamanho da Partícula , Triticum/química
20.
Vet Microbiol ; 198: 64-71, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28062009

RESUMO

Feed additives, including prebiotics, are commonly used alternatives to antimicrobial growth promoters to improve gut health and performance in broilers. Wheat bran is a highly concentrated source of (in)soluble fiber which is partly degraded by the gut microbiota. The aim of the present study was to investigate the potential of wheat bran as such to reduce colonization of the cecum and shedding of Salmonella bacteria in vivo. Also, the effect of particle size was evaluated. Bran with an average reduced particle size of 280µm decreased levels of cecal Salmonella colonization and shedding shortly after infection when compared to control groups and groups receiving bran with larger particle sizes. In vitro fermentation experiments revealed that bran with smaller particle size was fermented more efficiently, with a significantly higher production of butyric and propionic acid, compared to the control fermentation and fermentation of a larger fraction. Fermentation products derived from bran with an average particle size of 280µm downregulated the expression of hilA, an important invasion-related gene of Salmonella. This downregulation was reflected in an actual lowered invasive potential when Salmonella bacteria were pretreated with the fermentation products derived from the smaller bran fraction. These data suggest that wheat bran with reduced particle size can be a suitable feed additive to help control Salmonella infections in broilers. The mechanism of action most probably relies on a more efficient fermentation of this bran fraction and the consequent increased production of short chain fatty acids (SCFA). Among these SCFA, butyric and propionic acid are known to reduce the invasion potential of Salmonella bacteria.


Assuntos
Ração Animal/análise , Fibras na Dieta/análise , Tamanho da Partícula , Salmonelose Animal/dietoterapia , Ração Animal/microbiologia , Animais , Proteínas de Bactérias/genética , Derrame de Bactérias , Ceco/microbiologia , Galinhas , Dieta/veterinária , Fibras na Dieta/administração & dosagem , Ácidos Graxos Voláteis/metabolismo , Regulação Bacteriana da Expressão Gênica , Salmonella/fisiologia , Salmonelose Animal/microbiologia , Transativadores/genética
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