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1.
Carbohydr Polym ; 331: 121860, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38388056

RESUMO

Potato starch with mutations in starch branching enzyme genes (SBEI, SBEII) and granule-bound starch synthase gene (GBSS) was characterized for molecular and thermal properties. Mutations in GBSS were here stacked to a previously developed SBEI and SBEII mutation line. Additionally, mutations in the GBSS gene alone were induced in the wild-type variety for comparison. The parental line with mutations in the SBE genes showed a âˆ¼ 40 % increase in amylose content compared with the wild-type. Mutations in GBSS-SBEI-SBEII produced non-waxy, low-amylose lines compared with the wild-type. An exception was a line with one remaining GBSS wild-type allele, which displayed ∼80 % higher amylose content than wild-type. Stacked mutations in GBSS in the SBEI-SBEII parental line caused alterations in amylopectin chain length distribution and building block size categories of whole starch. Correlations between size categories of building blocks and unit chains of amylopectin were observed. Starch in GBSS-SBEI-SBEII mutational lines had elevated peak temperature of gelatinization, which was positively correlated with large building blocks.


Assuntos
Enzima Ramificadora de 1,4-alfa-Glucana , Solanum tuberosum , Sintase do Amido , Amilopectina/química , Sintase do Amido/genética , Sintase do Amido/metabolismo , Amilose , Solanum tuberosum/metabolismo , Estrutura Molecular , Amido/química , Mutação , Enzima Ramificadora de 1,4-alfa-Glucana/química
2.
Carbohydr Polym ; 316: 121030, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37321727

RESUMO

Six cross-bred barley lines developed by a breeding strategy with the target to enhance the fructan synthesis activity and reduce the fructan hydrolysis activity were analyzed together with their parental lines, and a reference line (Gustav) to determine whether the breeding strategy also affected the content and molecular structure of amylopectin and ß-glucan. The highest fructan and ß-glucan content achieved in the novel barley lines was 8.6 % and 12 %, respectively (12.3-fold and 3.2-fold higher than in Gustav). The lines with low fructan synthesis activity had higher starch content, smaller building blocks in amylopectin, and smaller structural units of ß-glucans than the lines with high-fructan synthesis activity. Correlation analysis confirmed that low starch content was associated with high amylose, fructan, and ß-glucan content, and larger building blocks in amylopectin.


Assuntos
Hordeum , beta-Glucanas , Amilopectina/química , Hordeum/química , Seleção Artificial , Estrutura Molecular , Amido/química , Amilose/química
3.
Sci Rep ; 13(1): 99, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36596824

RESUMO

Fermentation of dietary fiber by gut microbes produces short-chain fatty acids (SCFA), but fermentation outcomes are affected by dietary fiber source and microbiota composition. The aim of this study was to investigate the effect of two different fecal microbial compositions on in vitro fermentation of a standardized amount of oat, rye, and wheat breads. Two human fecal donors with different microbial community composition were recruited. Bread samples were digested enzymatically. An in vitro fermentation model was used to study SCFA production, dietary fiber degradation, pH, and changes in microbiota. Feces from donor I had high relative abundance of Bacteroides and Escherichia/Shigella, whereas feces from donor II were high in Prevotella and Subdoligranulum. Shifts in microbiota composition were observed during fermentation. SCFA levels were low in the samples with fecal microbiota from donor I after 8 h of fermentation, but after 24 h acetate and propionate levels were similar in the samples from the different donors. Butyrate levels were higher in the fermentation samples from donor II, especially with rye substrate, where high abundance of Subdoligranulum was observed. Dietary fiber degradation was also higher in the fermentation samples from donor II. In conclusion, fermentation capacity and substrate utilization differed between the two different microbiota compositions.


Assuntos
Microbiota , Triticum , Humanos , Triticum/metabolismo , Pão , Secale/metabolismo , Avena/metabolismo , Fermentação , Ácidos Graxos Voláteis/metabolismo , Fezes/química , Fibras na Dieta/metabolismo
4.
Polymers (Basel) ; 14(21)2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36365555

RESUMO

Environmental pollution by synthetic polymers is a global problem and investigating substitutes for synthetic polymers is a major research area. Starch can be used in formulating bioplastic materials, mainly as blends or composites with other polymers. The major drawbacks of using starch in such applications are water sensitivity and poor mechanical properties. Attempts have been made to improve the mechanical properties of starch-based blends and composites, by e.g., starch modification or plasticization, matrix reinforcement, and polymer blending. Polymer blending can bring synergetic benefits to blends and composites, but necessary precautions must be taken to ensure the compatibility of hydrophobic polymers and hydrophilic starch. Genetic engineering offers new possibilities to modify starch inplanta in a manner favorable for bioplastics applications, while the incorporation of antibacterial and/or antioxidant agents into starch-based food packaging materials brings additional advantages. In conclusion, starch is a promising material for bioplastic production, with great potential for further improvements. This review summarizes the recent advances in starch-based blends and composites and highlights the potential strategies for overcoming the major drawbacks of using starch in bioplastics applications.

5.
Sci Rep ; 12(1): 19151, 2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-36351972

RESUMO

High fructan content in the grain of cereals is an important trait in agriculture such as environmental resilience and dietary fiber food production. To understand the mechanism in determining final grain fructan content and achieve high fructan cereal, a cross breeding strategy based on fructan synthesis and hydrolysis activities was set up and have achieved barley lines with 11.8% storage fructan in the harvested grain. Our study discovered that high activity of fructan hydrolysis at later grain developmental stage leads to the low fructan content in mature seeds, simultaneously increasing fructan synthesis at early stage and decreasing fructan hydrolysis at later stage through crossing breeding is an efficient way to elevate grain diet-fiber content. A good correlation between fructan and beta glucans was also discovered with obvious interest. Field trials showed that the achieved high fructan barley produced over seven folds higher fructan content than control barley and pull carbon-flux to fructan through decreasing fructan hydrolysis without disruption starch synthesis will probably not bring yield deficiency.


Assuntos
Hordeum , Frutanos , Hidrólise , Melhoramento Vegetal , Fibras na Dieta , Grão Comestível , Dieta
6.
Ultrasound Med Biol ; 48(2): 333-345, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34802840

RESUMO

Magnetomotive ultrasound is an emerging technique that enables detection of magnetic nanoparticles. This has implications for ultrasound molecular imaging, and potentially addresses clinical needs regarding determination of metastatic infiltration of the lymphatic system. Contrast is achieved by a time-varying magnetic field that sets nanoparticle-laden regions in motion. This motion is governed by vector-valued mechanical and magnetic forces. Understanding how these forces contribute to observed displacement patterns is important for the interpretation of magnetomotive ultrasound images. Previous studies have captured motion adjacent to nanoparticle-laden regions that was attributed to diamagnetism. While diamagnetism could give rise to a force, it cannot fully account for the observed displacements in magnetomotive ultrasound. To isolate explanatory variables of the observed displacements, a finite element model is set up. Using this model, we explore potential causes of the unexplained motion by comparing numerical models with earlier experimental findings. The simulations reveal motion outside particle-laden regions that could be attributed to mechanical coupling and the principle of mass conservation. These factors produced a motion that counterbalanced the time-varying magnetic excitation, and whose extent and distribution was affected by boundary conditions as well as compressibility and stiffness of the surroundings. Our findings emphasize the importance of accounting for the vector-valued magnetic force in magnetomotive ultrasound imaging. In an axisymmetric geometry, that force can be represented by a simple scalar expression, an oversimplification that rapidly becomes inaccurate with distance from the symmetry axis. Additionally, it results in an underestimation of the vertical force component by up to 30%. We therefore recommend using the full vector-valued force to capture the magnetic interaction. This study enhances our understanding of how forces govern magnetic nanoparticle displacement in tissue, contributing to accurate analysis and interpretation of magnetomotive ultrasound imaging.


Assuntos
Campos Magnéticos , Magnetismo , Análise de Elementos Finitos , Movimento (Física) , Ultrassonografia
7.
Sci Rep ; 11(1): 4311, 2021 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-33619312

RESUMO

DNA-free genome editing was used to induce mutations in one or two branching enzyme genes (Sbe) in tetraploid potato to develop starch with an increased amylose ratio and elongated amylopectin chains. By using ribonucleoprotein (RNP) transfection of potato protoplasts, a mutation frequency up to 72% was achieved. The large variation of mutations was grouped as follows: Group 1 lines with all alleles of Sbe1 mutated, Group 2 lines with all alleles of Sbe1 as well as two to three alleles of Sbe2 mutated and Group 3 lines having all alleles of both genes mutated. Starch from lines in Group 3 was found to be essentially free of amylopectin with no detectable branching and a chain length (CL) distribution where not only the major amylopectin fraction but also the shortest amylose chains were lost. Surprisingly, the starch still formed granules in a low-ordered crystalline structure. Starch from lines of Group 2 had an increased CL with a higher proportion of intermediate-sized chains, an altered granule phenotype but a crystalline structure in the granules similar to wild-type starch. Minor changes in CL could also be detected for the Group 1 starches when studied at a higher resolution.


Assuntos
Enzima Ramificadora de 1,4-alfa-Glucana/genética , Enzima Ramificadora de 1,4-alfa-Glucana/metabolismo , Amilose/metabolismo , Mutagênese , Solanum tuberosum/enzimologia , Solanum tuberosum/genética , Amido/metabolismo , Alelos , Amilose/química , Biomassa , Sistemas CRISPR-Cas , Edição de Genes , Genótipo , Espectroscopia de Ressonância Magnética , Mutação , Fenótipo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Polimerização
8.
Carbohydr Polym ; 255: 117503, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33436256

RESUMO

To determine the internal structure of barley starch without amylopectin isolation, whole starch was hydrolyzed using ß-amylase to remove the linear amylose and obtain ß-limit dextrins (ß-LDs). The ß-LDs were treated with extensive α-amylase to prepare α-limit dextrins (α-LDs), and the α-LDs were further hydrolyzed with ß-amylase into building blocks. The chain-length distribution of ß-LD and building block composition were analyzed by size-exclusion chromatography and anion-exchange chromatography. The internal structure of the barley whole starches had similar pattern to barley amylopectins analyzed by conventional methods. The starch of barley amo1-mutated varieties contained more short internal B-chains and less long internal B-chains than that of other varieties. The starch from amo1-mutated varieties had more large building blocks than that from waxy varieties. The simplified method presented in this study can effectively characterize starch internal structure that relates to physicochemical properties of starch, although some details of amylopectin structure are not assessable.


Assuntos
Amilopectina/análise , Amilose/análise , Dextrinas/análise , Amido/química , alfa-Amilases/química , beta-Amilase/química , Amilopectina/química , Amilose/química , Sequência de Carboidratos , Cromatografia em Gel , Cromatografia por Troca Iônica , Dextrinas/química , Hordeum/química , Humanos , Hidrólise
9.
Sci Rep ; 10(1): 21767, 2020 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-33303871

RESUMO

Date fruits vary widely in the hardness of their edible parts and they are classified accordingly into soft, semi-dry, and dry varieties. Fruit texture, a significant parameter in determining consumer acceptance, is related to the tissue structure and chemical composition of the fruit, mainly the ratio of sucrose to reducing sugars. This study aimed to understand the relationship between the chemical composition, microstructure, and texture profile of 10 major Emirati date fruits. The soluble sugars, glucose and fructose, represent ca 80 g/100 g of the fruits on the basis of dry weight (DW) while the dietary fiber contents varied 5.2-7.4 g/100 dg D.W. with lignin being the main determinant of the variability. The textures of the samples were studied using instrumental texture profile analysis. While no correlation was found between the soluble sugar and texture parameters in this study, the different fiber constituents correlated variably with the different parameters of date fruit texture. Lignin, arabinoxylan, galactomannan, and pectin were found to correlate significantly with fruit hardness and the related parameters, gumminess and chewiness. Both lignin and arabinoxylan correlated with resilience, and arabinoxylan exhibited a strong correlation with cohesiveness.


Assuntos
Fibras na Dieta/análise , Dureza , Phoeniceae/química , Phoeniceae/classificação , Frutose/análise , Galactose/análogos & derivados , Glucose/análise , Lignina/análise , Mananas/análise , Microscopia , Pectinas/análise , Phoeniceae/ultraestrutura , Sacarose/análise , Xilanos/análise
10.
Artigo em Inglês | MEDLINE | ID: mdl-32244813

RESUMO

Human consumption of fruits and vegetables are generally below recommended levels. Waste from the production, e.g., of un-used parts such as broccoli leaves and stem when producing broccoli florets for food, is a sustainability issue. In this study, broccoli leaves were analyzed for the content of various dietary fibre and phenolics, applying the Uppsala method and HPLC analyses, respectively. The results showed that broccoli leaves had comparable levels of dietary fibre (26%-32% of dry weight (DW)) and phenolic compounds (6.3-15.2 mg/g DW) to many other food and vegetables considered valuable in the human diet from a health perspective. A significant positive correlation was found among soluble dietary fibre and phenolic acids indicating possible bindings between these components. Seasonal variations affected mainly the content of conjugated phenolics, and the content of insoluble dietary fibre. This study verified the importance of the use of broccoli production side streams (leaves) as they may contribute with health promoting components to the human diet and also socio-economic and environmental benefits to the bioeconomic development in the society.


Assuntos
Brassica , Ingredientes de Alimentos , Folhas de Planta , Brassica/química , Clima , Ingredientes de Alimentos/análise , Humanos , Fenóis/análise , Folhas de Planta/química
11.
Data Brief ; 25: 104192, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31321274

RESUMO

In this data article, we report real-world data on multichannel connectivity and videotransmission carried on commercial 3G/4G networks in the region of Skåne, southern Sweden. The data reported here complement the research article "Technical feasibility and ambulance nurses' view of a digital telemedicine system in pre-hospital stroke care - A pilot study" (1). The dataset was originally collected as part of a project aimed to test in a clinical setting the quality and usefulness of a linked image and sound transmission in the prehospital assessment of patients with suspected stroke. The project built on previous studies indicating that using high-quality telemedicine in stroke cases is feasible and has already impacted local stroke care Schwamm et al., 2009. In addition, studies support the hypothesis that stroke telemedicine consultations, compared with telephone-only, result in more accurate decision-making Demaerschalk et al., 2012. Cellular networks for 3/4G networks have been greatly improved, a prerequisite for the use of these networks for e. g. medical applications. However, connectivity maps for planning purposes are usually based on theoretical values that do not consider smaller features of the terrain such as large trees, hills, rocks etc. and that may interfere with connectivity. To leverage several networks, multichannel devices have been developed that split the original transmission onto several independent channels and recombine the transmission on the receiver side. This setup allows to increase the available bandwidth and introduces at the same time an element of redundancy, provided that several providers with independent networks are used.

12.
Int Emerg Nurs ; 44: 35-40, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31047854

RESUMO

BACKGROUND: High-quality telemedicine in cases of suspected stroke has comparable precision with on-site medical examinations. A novel technical concept was developed in order to deliver a video/audio system to achieve more efficient patient assessment and diagnostic support. AIMS AND OBJECTIVES: The aim of the present pilot-study was to evaluate in a clinical setting the quality of a linked image and sound transmission in the prehospital assessment of patients with suspected stroke. In addition, we wanted to elucidate how ambulance nurses experienced the use of this innovative technology. DESIGN: The study used a quantitative method using questionnaires with fixed response options, combined with a qualitative approach to assess complementary statements of prehospital emergency care nurses (PEN) that had used the system. METHODS: The study was conducted in one ambulance care office and one hospital in southern Sweden. Six PEN and one neurological specialist (Dr) expressed their perceptions based on 11 cases with suspected stroke. Responses were assessed in the dimensions of the technology (Dr - image quality/sound quality; Dr and PEN), safety, sense of increased control and uniform assessment. A questionnaire technique was used, complemented with a qualitative part of the content analysis (PEN views). RESULTS: In the technology dimension, the Dr evaluated the image quality as Very good to Good (100%) while 75% of PEN answered that the digital stroke concept felt reliable to use and the digital stroke assessment is believed to increase uniform assessment. Asked if the present digital concept should be further developed and if further digital systems should be developed in general, the PEN were split in their responses (50 vs 50%), which could be related to a conception of unclear efficacy of the concept. Descriptions of the decisive comments emerged in three categories; Minor operating interference, Physician's competence crucial and Unclear efficacy. CONCLUSION: All respondents seem to have confidence in the assessed digital stroke concept. The image quality is perceived suitable in the assessment situation but the nurses expressed ambiguity about the efficiency of the entire concept. The ambulance nurses also highlighted the physician's skills and personality as important factors for further development of the concept.


Assuntos
Enfermeiras e Enfermeiros/psicologia , Acidente Vascular Cerebral/terapia , Telemedicina/normas , Adulto , Ambulâncias/estatística & dados numéricos , Serviços Médicos de Emergência/métodos , Serviços Médicos de Emergência/normas , Desenho de Equipamento/normas , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Enfermeiras e Enfermeiros/estatística & dados numéricos , Projetos Piloto , Inquéritos e Questionários , Suécia , Telemedicina/métodos
13.
Nutrients ; 10(11)2018 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-30380770

RESUMO

Sourdough fermented bread has been suggested to have beneficial health effects, in part mediated by increased satiety in the postprandial phase, but only limited research has been conducted to verify this. The current study aimed to investigate the effect of the amounts of sourdough and rye in soft bread on postprandial appetite. On 6 occasions, 23 healthy volunteers consumed 5 different test breads, with varying amount of rye and sourdough, and a yeast-fermented refined wheat control bread as part of a breakfast meal. The sourdough ranged between 9⁻51% of dough weight and rye content between 35⁻48% of flour weight. Appetite was recorded using visual analogue scales from immediately before breakfast and every 30 min the following 4 h. An ad libitum lunch was served 4 h after the breakfast meal, from which voluntary energy intake was measured. While some of the test breads resulted in lower hunger ratings and increased sense of fullness compared to the refined wheat bread, there were no differences between the test breads. The content of rye in the test breads differed within a narrow range, which might explain the lack of a consistent effect of rye on appetite. Microstructural examination of the test breads showed an increased aggregation of proteins in the breads with high content of sourdough, indicating additional changes to the breads, beyond change in pH, which may counteract the potential effect of decreased pH in the bread on appetite. In conclusion, our study does not support an effect of sourdough on appetite and ad libitum food intake.


Assuntos
Apetite , Pão/análise , Ingestão de Alimentos , Adulto , Idoso , Desjejum , Estudos Cross-Over , Ingestão de Energia , Feminino , Fermentação , Farinha/análise , Voluntários Saudáveis , Humanos , Fome/fisiologia , Masculino , Pessoa de Meia-Idade , Período Pós-Prandial , Secale , Triticum , Adulto Jovem
14.
Food Chem ; 251: 58-63, 2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29426424

RESUMO

Tubers from a genetically modified high-amylose line T-2012 and its parental potato cultivar Dinamo were analyzed for resistant starch (RS) and dietary fiber (DF) after cooking and cold storage. For uncooked potatoes, the high-amylose tubers (30% of dry matter, DM) had much lower RS than the parent tubers (56% of DM). However, after cooking, the high-amylose tubers gave more RS (13% of DM) than the parent (4% of DM), and the RS level increased further to about 20% of DM after 1 day of cold storage. The altered RS content was attributable to changes in amylose content, starch granule structure, and amylopectin structure induced by the genetic modification. The high-amylose tubers also contained more DF (10-14% of DM) than the parent (5-7% of DM). Furthermore, cell wall composition was indirectly affected by the genetic modification, giving more cellulose and less pectin in the high-amylose tubers than the parent.


Assuntos
Fibras na Dieta/análise , Tubérculos/química , Solanum tuberosum/química , Amido/química , Amilopectina/química , Amilose/química , Parede Celular/química , Culinária , Pectinas/análise , Plantas Geneticamente Modificadas , Solanum tuberosum/genética , Amido/análise
15.
Mol Plant ; 10(12): 1556-1570, 2017 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-29126994

RESUMO

Sequential carbohydrate synthesis is important for plant survival because it guarantees energy supplies for growth and development during plant ontogeny and reproduction. Starch and fructan are two important carbohydrates in many flowering plants and in human diets. Understanding this coordinated starch and fructan synthesis and unraveling how plants allocate photosynthates and prioritize different carbohydrate synthesis for survival could lead to improvements to cereals in agriculture for the purposes of greater food security and production quality. Here, we report a system from a single gene in barley employing two alternative promoters, one intronic/exonic, to generate two sequence-overlapping but functionally opposing transcription factors, in sensing sucrose, potentially via sucrose/glucose/fructose/trehalose 6-phosphate signaling. The system employs an autoregulatory mechanism in perceiving a sucrose-controlled trans activity on one promoter and orchestrating the coordinated starch and fructan synthesis by competitive transcription factor binding on the other promoter. As a case in point for the physiological roles of the system, we have demonstrated that this multitasking system can be exploited in breeding barley with tailored amounts of fructan to produce healthy food ingredients. The identification of an intron/exon-spanning promoter in a hosting gene, resulting in proteins with distinct functions, adds to the complexity of plant genomes.


Assuntos
Frutanos/metabolismo , Amido/metabolismo , Sacarose/metabolismo , Metabolismo dos Carboidratos/genética , Regulação da Expressão Gênica de Plantas/genética
16.
Sci Rep ; 7(1): 4824, 2017 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-28684867

RESUMO

Current methods for intra-surgical guidance to localize metastases at cancer surgery are based on radioactive tracers that cause logistical challenges. We propose the use of a novel ultrasound-based method, magnetomotive ultrasound (MMUS) imaging that employ a nanoparticle-based contrast agent that also may be used for pre-operative PET/MRI imaging. Since MMUS is radiation free, this eliminates the dependence between pre- and intra-operative imaging and the radiation exposure for the surgical staff. This study investigates a hypothetical clinical scenario of pre-operative PET imaging, combined with intra-operative MMUS imaging, implemented in a sentinel lymph node (SLN) rat model. At one-hour post injection of 68Ga-labelled magnetic nanoparticles, six animals were imaged with combined PET/CT. After two or four days, the same animals were imaged with MMUS. In addition, ex-vivo MRI was used to evaluate the amount of nanoparticles in each single SLN. All SLNs were detectable by PET. Four out of six SLNs could be detected with MMUS, and for these MMUS and MRI measurements were in close agreement. The MRI measurements revealed that the two SLNs undetectable with MMUS contained the lowest nanoparticle concentrations. This study shows that MMUS can complement standard pre-operative imaging by providing bedside real-time images with high spatial resolution.


Assuntos
Meios de Contraste/química , Radioisótopos de Gálio/química , Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Linfonodo Sentinela/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia/métodos , Animais , Meios de Contraste/farmacocinética , Feminino , Compostos Férricos/química , Radioisótopos de Gálio/farmacocinética , Humanos , Imageamento por Ressonância Magnética/instrumentação , Nanopartículas de Magnetita/química , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/instrumentação , Ratos , Ratos Wistar , Biópsia de Linfonodo Sentinela , Coloração e Rotulagem/métodos , Tomografia Computadorizada por Raios X/instrumentação , Ultrassonografia/instrumentação
17.
J Sci Food Agric ; 96(14): 4821-4827, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27450418

RESUMO

BACKGROUND: Butyric acid is produced by degradation of dietary fibre by microbiota and is crucial for maintaining a healthy colon. The physicochemical properties are important for butyric acid formation, and this study aimed to evaluate the use of malting to tailor the functional characteristics of barley dietary fibre. The effect of different steeping conditions was evaluated in laboratory-scale malting experiments with three different barley varieties. RESULTS: Steeping at 35°C and with 0.4 % (v/v) lactic acid resulted in a higher content of ß-glucan and soluble fibre in malts than in those steeped at lower temperature and lower lactic acid concentration. Resistant starch increased, whereas the content of soluble arabinoxylan was lower. Dietary fibre components in Tipple were more affected by steeping conditions than the other varieties. The total contents of iron, phytate and amylose were little influenced by steeping conditions. CONCLUSION: The selection of steeping conditions during malting influences composition and the characteristics of dietary fibre in barley. However, the choice of barley variety is also important for tailoring of functional ingredients beneficial for colonic health. © 2016 The Authors. Journal of the Science of Food and Agriculture published by JohnWiley & Sons Ltd on behalf of Society of Chemical Industry.


Assuntos
Ácido Butírico/química , Hordeum/química , Fibras na Dieta/análise , Manipulação de Alimentos , Hordeum/classificação , Plântula/química , Temperatura , Fatores de Tempo , Água
18.
Int J Biol Macromol ; 81: 730-5, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26361866

RESUMO

Barley spikes of the cultivars/breeding lines Gustav, Karmosé and SLU 7 were harvested at 9, 12 and 24 days after flowering in order to study starch structure in developing barley endosperm. Kernel dry weight, starch content and amylose content increased during development. Structural analysis was performed on whole starch and included the chain-length distribution of the whole starches and their ß-limit dextrins. Karmosé, possessing the amo1 mutation, had higher amylose content and a lower proportion of long chains (DP ≥38) in the amylopectin component than SLU 7 and Gustav. Structural differences during endosperm development were seen as a decrease in molar proportion of chains of DP 22-37 in whole starch. In ß-limit dextrins, the proportion of Bfp-chains (DP 4-7) increased and the proportion of BSmajor-chains (DP 15-27) decreased during development, suggesting more frequent activity of starch branching enzymes at later stages of maturation, resulting in amylopectin with denser structure.


Assuntos
Endosperma/química , Hordeum/química , Amido/química , Enzima Ramificadora de 1,4-alfa-Glucana/química , Amilose/química , Cruzamento , Hordeum/genética , Mutação , Amido/isolamento & purificação
19.
Int J Biol Macromol ; 81: 692-700, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26342462

RESUMO

Amylopectin fine structure and starch gelatinization and retrogradation were studied in 10 different barley cultivars/breeding lines. Clusters and building blocks were isolated from the amylopectin by α-amylase from Bacillus amyloliquefaciens and their structure was characterized. Gelatinization was studied at a starch:water ratio of 1:3, and retrogradation was studied on gelatinized starch at starch:water ratio of 1:2, by differential scanning calorimetry. Three barley cultivars/breeding lines possessed the amo1 mutation, and they all had a lower molar proportion of chains of DP ≥38 and more of large building blocks. The amo1 mutation also resulted in a higher gelatinization temperature and a broader temperature interval during gelatinization. Overall, small clusters with a dense structure resulted in a higher gelatinization temperature while retrogradation was promoted by short chains in the amylopectin and many large building blocks.


Assuntos
Hordeum/química , Amido/química , Amilopectina/química , Varredura Diferencial de Calorimetria , Amido/isolamento & purificação , Temperatura , alfa-Amilases/química
20.
Food Funct ; 6(9): 3165-76, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26227569

RESUMO

Barley malt, a product of controlled germination, has been shown to produce high levels of butyric acid in the cecum and portal serum of rats and may therefore have anti-inflammatory effects. The aim of the study was to investigate how four barley malts, caramelized and colored malts, 50-malt and 350-malt, differing in functional characteristics concerning beta-glucan content and color, affect short-chain fatty acids (SCFA), barrier function and inflammation in the hindgut of rats fed high-fat diets. Male Wistar rats were given malt-supplemented high-fat diets for four weeks. Low and high-fat diets containing microcrystalline cellulose were incorporated as controls. All diets contained 70 g kg(-1) dietary fiber. The malt-fed groups were found to have had induced higher amounts of butyric and propionic acids in the hindgut and portal serum compared with controls, while cecal succinic acid only increased to a small extent. Fat increased the mRNA expression of tight junction proteins and Toll-like receptors (TLR) in the small intestine and distal colon of the rats, as well as the concentration of some amino acids in the portal plasma, but malt seemed to counteract these adverse effects to some extent. However, the high content of advanced glycation end-products (AGE) in caramelized malt tended to prohibit the positive effects on occludin in the small intestine and plasma amino acids seen with the other malt products. In conclusion, malting seems to be an interesting process for producing foods with positive health effects, but part of these effects may be destroyed if the malt contains a high content of AGE.


Assuntos
Ácido Butírico/metabolismo , Sistema Digestório/metabolismo , Produtos Finais de Glicação Avançada/análise , Hordeum/química , Hordeum/metabolismo , Sementes/crescimento & desenvolvimento , Proteínas de Junções Íntimas/genética , Receptores Toll-Like/genética , Animais , Ceco/metabolismo , Dieta Hiperlipídica/efeitos adversos , Manipulação de Alimentos , Germinação , Produtos Finais de Glicação Avançada/metabolismo , Hordeum/crescimento & desenvolvimento , Masculino , Ratos , Ratos Wistar , Sementes/química , Sementes/metabolismo , Proteínas de Junções Íntimas/metabolismo , Receptores Toll-Like/metabolismo , beta-Glucanas/análise , beta-Glucanas/metabolismo
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