Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 17 de 17
Filter
1.
J Athl Train ; 2023 Dec 20.
Article in English | MEDLINE | ID: mdl-38116803

ABSTRACT

OBJECTIVE: Exercise-associated dehydration is a common problem, especially at sporting events. Although there are recommendations to drink a certain volume per kg body mass lost after exercise, there is no clear guidance about the type of rehydration beverage. The aim of this systematic review is to assess the effectiveness of carbohydrate-electrolyte solutions as a rehydration solution for exercise-associated dehydration. DATA SOURCES: Medline (via the PubMed interface), Embase and the Cochrane Library were searched for relevant studies. The search is up to date until June 2022. STUDY SELECTION: Controlled trials involving adults and children were included if dehydration was the result of physical exercise and if drinking carbohydrate-electrolyte solutions, of any percentage carbohydrate, was compared with drinking water. All languages were included as long as an English abstract was available. DATA EXTRACTION: Data on study design, study population, interventions, outcome measures and study limitations were extracted from each included article. Certainty was assessed using GRADE. DATA SYNTHESIS: Out of 3485 screened articles, 19 studies were included that assessed carbohydrate-electrolyte solutions (0% - 9% carbohydrate) compared with water. Although there is variability amongst the identified studies, drinking 0-3.9% and, especially, 4-9% carbohydrate-electrolyte (CE) solution may be effective for rehydration. CONCLUSIONS: A potential beneficial effect of drinking CE drinks compared with water was seen for many of the reviewed outcomes. Commercial CE drinks (ideally 4-9% CE drinks or alternatively 0-3.9% CE drinks) could be suggested for rehydration in persons with exercise associated dehydration when whole foods are not available.

2.
J Athl Train ; 2023 Dec 20.
Article in English | MEDLINE | ID: mdl-38116818

ABSTRACT

OBJECTIVE: Dehydration associated with exertion is a commonly encountered condition in the first aid setting, particularly at outdoor sporting events. Part I of this back-to-back review demonstrated that commercial sports drinks can be suggested for effective restoration of fluid balance in dehydrated persons. This systematic review was undertaken to compare alternative liquids, such as milk, beer, and coconut water, with water for effective oral rehydration after prolonged exercise. DATA SOURCES: Cochrane Library, PubMed, and Embase were searched for relevant literature in June 2022. STUDY SELECTION: Controlled experimental and observational studies involving adults and children were included when dehydration was induced by physical exercise and oral rehydration fluids were administered and compared with regular water. No additional food intake accompanied the rehydration drinks or water. Articles in all languages were included if an English abstract was available. DATA EXTRACTION: The study design, study population, intervention, outcome measures, and study limitations were extracted from each included article. DATA SYNTHESIS: Out of 3485 records, 11 studies were included comparing skim or low-fat milk, coconut water, and beer (0-5% alcohol) with water. Four studies showed that drinking skim or low-fat milk, without additional food intake, led to a statistically significant improved volume/hydration status when compared with drinking water. In three trials, no significant differences were shown at multiple timepoints for outcomes related to volume and hydration status following rehydration with fresh coconut water compared with water. Lastly, there is insufficient evidence to recommend beer for rehydration (0-5% alcohol). CONCLUSIONS: Consuming skim or low-fat cow's milk without additional food as compared with water appears to improve volume/hydration status in persons with exercise-induced dehydration. However, evidence is of very low certainty and should be interpreted with caution.

3.
PLoS One ; 17(4): e0266078, 2022.
Article in English | MEDLINE | ID: mdl-35404977

ABSTRACT

INTRODUCTION: HIV prevalence and sexual risk have been estimated very high for transgender people. However, the limited sampling and data collection methods used in current research on transgender people potentially led to overrepresentation and generalisation of people at risk for HIV. Current HIV prevalence estimates in transgender populations are generalised from studies mainly focusing on transgender women engaging in sex work. Moreover, studies focusing on non-binary people, who identify with a broad range of identities beyond the traditional male and female gender identities, are scarce. OBJECTIVES: To estimate the HIV prevalence rate in the Flemish and Brussels (Belgium) transgender population, including transgender women, transgender men and non-binary people, and to identify the associated risk factors. METHODS: In this community-based cross-sectional study, self-identified transgender and non-binary (TGNB) people will be recruited through a two-stage time-location sampling approach. First, community settings in which TGNB people gather will be mapped to develop an accurate sampling frame. Secondly, a multistage sampling design is applied involving a stratification based on setting type (healthcare facilities vs outreach events), a selection of clusters by systematic sampling and a simple random selection of TGNB people within each cluster. Participants will complete an electronic self-reported survey to measure sociological, sexual and drug-using behaviors (risk factors) and oral fluid aliquots will be collected and tested for HIV antibodies. Logistic regression models will be used to evaluate risk factors independently associated with HIV infection. The presented study is registered at ClinicalTrials.gov (NCT04930614). DISCUSSION: This study will be the first to investigate the HIV prevalence rates and associated risk behaviors in an accurate representation of the TGNB population in a Western European country. The findings will globally serve as a knowledge base for identifying subgroups at risk for becoming infected with HIV within TGNB people and to set up targeted prevention programs.


Subject(s)
HIV Infections , Transgender Persons , Belgium/epidemiology , Cross-Sectional Studies , Female , HIV Infections/epidemiology , HIV Infections/prevention & control , Humans , Male , Prevalence , Risk Factors , Sexual Behavior
4.
Food Chem ; 362: 130203, 2021 Nov 15.
Article in English | MEDLINE | ID: mdl-34091172

ABSTRACT

In the crumb of fresh white wheat bread, starch is fully gelatinized. Its molecular and three-dimensional structure are major factors limiting the rate of its digestion. The aim of this study was to in situ modify starch during bread making with starch-modifying enzymes (maltogenic amylase and amylomaltase) and to investigate the impact thereof on bread characteristics, starch retrogradation and digestibility. Maltogenic amylase treatment increased the relative content of short amylopectin chains (degree of polymerization ≤ 8). This resulted in lower starch retrogradation and crumb firmness upon storage, and reduced extent (up to 18%) of in vitro starch digestion for fresh and stored breads. Amylomaltase only modestly shortened amylose chains and had no measurable impact on amylopectin structure. Modification with this enzyme led to slower bread crumb firming but did not influence starch digestibility.


Subject(s)
Bread , Glycogen Debranching Enzyme System/chemistry , Glycoside Hydrolases/chemistry , Starch/pharmacokinetics , Triticum , Amylopectin/chemistry , Amylopectin/metabolism , Amylose/chemistry , Freeze Drying , Glycogen Debranching Enzyme System/metabolism , Glycoside Hydrolases/metabolism , Starch/chemistry , Triticum/chemistry
5.
Transfusion ; 61(7): 2125-2136, 2021 07.
Article in English | MEDLINE | ID: mdl-33955570

ABSTRACT

BACKGROUND: Transfusion-transmissible infections such as hepatitis B virus (HBV) remain a major concern for the safety of blood transfusion. This cross-sectional study aimed to assess the trend of HBV prevalence and associated risk factors among a first-time donor population in a low endemic country. STUDY DESIGN AND METHODS: Between 2010 and 2018, blood samples were collected from first-time donors presented at donor collection sites of Belgian Red Cross-Flanders. They were tested for hepatitis B surface antigen (HBsAg), hepatitis B core antibodies (anti-HBc), and HBV DNA, HIV and hepatitis virus C (HCV) antibodies and RNA, and syphilis antibodies. RESULTS: A total of 211,331 first-time blood donors (43.7% males, median age 25 years) were analyzed. HBsAg prevalence decreased from 0.06% in 2010 to 0.05% in 2018 (p = .004) and this declining trend was accompanied by an increased number of donors in the HBV vaccinated birth cohort (p < .001). HBsAg prevalence was 0.33% in foreign-born donors and 0.02% in Belgian natives (p < .001). Multivariate risk profiling showed that anti-HBc positivity was significantly associated with mainly foreign-born donors (odds ratio [OR] = 9.24) but also with older age (OR = 1.06), male gender (OR = 1.32), year of blood donation (OR = 0.94), and co-infections with HCV (OR = 4.31) or syphilis (OR = 4.91). DISCUSSION: The decreasing trend in HBV prevalence could mainly be explained by the introduction of the universal HBV vaccination. Being born in endemic areas was the most important predictor for HBV infection while the co-infections with syphilis suggest unreported sexual risk contacts.


Subject(s)
Blood Donors , Emigrants and Immigrants/statistics & numerical data , Hepatitis B Vaccines , Hepatitis B virus/isolation & purification , Hepatitis B/epidemiology , Transfusion Reaction/prevention & control , Vaccination , Viremia/epidemiology , Adolescent , Adult , Age Factors , Belgium/epidemiology , Cross-Sectional Studies , Female , Hepatitis B/blood , Hepatitis B Antibodies/blood , Hepatitis B Core Antigens/immunology , Hepatitis B Surface Antigens/blood , Humans , Male , Middle Aged , Prevalence , Risk Factors , Sex Factors , Urban Population , Viremia/blood , Young Adult
6.
J Agric Food Chem ; 69(13): 3912-3922, 2021 Apr 07.
Article in English | MEDLINE | ID: mdl-33780246

ABSTRACT

The structural heterogeneity of water-extractable arabinoxylan (WE-AX) impacts wheat flour functionality. 1H diffusion-ordered (DOSY) nuclear magnetic resonance (NMR) spectroscopy revealed structural heterogeneity within WE-AX fractions obtained via graded ethanol precipitation. Combination with high-resolution 1H-1H correlation NMR spectroscopy (COSY) allowed identifying the relationship between the xylose substitution patterns and diffusion properties of the subpopulations. WE-AX fractions contained distinct subpopulations with different diffusion rates. WE-AX subpopulations with a high self-diffusivity contained high levels of monosubstituted xylose. In contrast, those with a low self-diffusivity were rich in disubstituted xylose, suggesting that disubstitution mainly occurs in WE-AX molecules with large hydrodynamic volumes. In general, WE-AX fractions precipitating at higher and lower ethanol concentrations had higher and lower self-diffusivity and more and less complex substitution patterns. Although 1H DOSY NMR, as performed in this study, was valuable for elucidating WE-AX structural heterogeneity, physical limitations arose when studying WE-AX populations with high molecular weight dispersions.


Subject(s)
Flour , Triticum , Flour/analysis , Magnetic Resonance Spectroscopy , Water , Xylans
7.
Foods ; 10(2)2021 Feb 02.
Article in English | MEDLINE | ID: mdl-33540801

ABSTRACT

The fine molecular structure of starch governs its functionality and digestibility, and enzymatic approaches can be utilized to tailor its properties. The aim of this study was to investigate the in situ modification of starch by amylomaltase (AMM) from Thermus thermophilus in model starch systems subjected to hydrothermal treatments under standardized conditions and the relationship between molecular structure, rheological properties and in vitro digestibility. When low dosages of AMM were added to a wheat starch suspension prior to submitting it to a temperature-time profile in a Rapid Visco Analyzer, the increased peak viscosity observed was attributed to partial depolymerization of amylose, which facilitated starch swelling and viscosity development. At higher dosages, the effect was smaller. The low cold paste viscosity as a result of the activity of AMM reflected substantial amylose depolymerization. At the same time, amylopectin chains were substantially elongated. The longer amylopectin chains were positively correlated (R2 = 0.96) with the melting enthalpies of retrograded starches, which, in turn, were negatively correlated with the extent (R2 = 0.92) and rate (R2 = 0.79) of in vitro digestion. It was concluded that AMM has the potential to be used to deliver novel starch functionalities and enhance its nutritional properties.

8.
J Trauma Stress ; 34(3): 538-550, 2021 06.
Article in English | MEDLINE | ID: mdl-33217083

ABSTRACT

Trauma-exposed individuals are at risk of developing mental health problems, including posttraumatic stress disorder (PTSD). As an exposed individual's friend or family member may be the first person to provide posttrauma relief, informing and training laypeople in psychosocial first aid may benefit mental health outcomes of trauma-exposed individuals. We aimed to (a) collect the best available evidence on communication as a first aid intervention in assisting individuals following traumatic events and (b) formulate practical recommendations. Systematic literature searches were conducted in three databases (March 2019). Following study selection, the extracted data were tabulated and synthesized narratively. The evidence was appraised according to the GRADE methodology and evaluated by a multidisciplinary expert panel to formulate recommendations for practice. Out of 1,724 articles, no experimental studies were identified, showing a complete lack of high-quality controlled studies on the efficacy of communicative practices. However, when lower-quality study designs were included, nine cross-sectional studies constituted the best available evidence. The studies suggested that positive communication by family members, r = -.38, aOR = 0.26, ß = -.22, p < .001-p < .05, and expressive coping by the victim, ß = -.62, p < .001, were associated with PTSD diagnosis and/or symptom severity; however, the evidence was of very low certainty. The expert panel took the methodological limitations into account when formulating weak practical recommendations. Cross-sectional studies currently provide the best possible evidence for developing guidelines on psychosocial first aid. High-quality controlled studies are needed to establish casual associations and identify the most effective interventions.


Subject(s)
Stress Disorders, Post-Traumatic , Adaptation, Psychological , Cross-Sectional Studies , First Aid , Humans , Stress Disorders, Post-Traumatic/therapy
9.
PLoS One ; 15(12): e0244052, 2020.
Article in English | MEDLINE | ID: mdl-33320910

ABSTRACT

INTRODUCTION: The novel Coronavirus Disease (COVID-19) outbreak currently puts health care workers at high risk of both physical and mental health problems. This study aimed to identify the risk and protective factors for mental health outcomes in health care workers during coronavirus epidemics. METHODS: A rapid systematic review was performed in three databases (March 24, 2020) and a current COVID-19 resource (May 28, 2020). Following study selection, study characteristics and effect measures were tabulated, and data were synthesized by using vote counting. Meta-analysis was not possible because of high variation in risk factors, outcomes and effect measures. Risk of bias of each study was assessed and the certainty of evidence was appraised according to the GRADE methodology. RESULTS: Out of 2605 references, 33 observational studies were selected and the identified risk and protective factors were categorized in ten thematic categories. Most of these studies (n = 23) were performed during the SARS outbreak, seven during the current COVID-19 pandemic and three during the MERS outbreak. The level of disease exposure and health fear were significantly associated with worse mental health outcomes. There was evidence that clear communication and support from the organization, social support and personal sense of control are protective factors. The evidence was of very low certainty, because of risk of bias and imprecision. CONCLUSION: Safeguarding mental health of health care workers during infectious disease outbreaks should not be treated as a separate mental health intervention strategy, but could benefit from a protective approach. This study suggests that embedding mental health support in a safe and efficient working environment which promotes collegial social support and personal sense of control could help to maximize resilience of health care workers. Low quality cross-sectional studies currently provide the best possible evidence, and further research is warranted to confirm causality.


Subject(s)
COVID-19/epidemiology , Coronavirus Infections/epidemiology , Mental Health , Severe Acute Respiratory Syndrome/epidemiology , COVID-19/complications , COVID-19/virology , Coronavirus/pathogenicity , Coronavirus Infections/complications , Coronavirus Infections/virology , Cross-Sectional Studies , Disease Outbreaks , Health Personnel , Humans , Middle East Respiratory Syndrome Coronavirus/pathogenicity , Pandemics , SARS-CoV-2/pathogenicity , Severe Acute Respiratory Syndrome/complications , Severe Acute Respiratory Syndrome/virology
10.
Resuscitation ; 156: A240-A282, 2020 Nov.
Article in English | MEDLINE | ID: mdl-33098920

ABSTRACT

This is the summary publication of the International Liaison Committee on Resuscitation's 2020 International Consensus on First Aid Science With Treatment Recommendations. It addresses the most recent published evidence reviewed by the First Aid Task Force science experts. This summary addresses the topics of first aid methods of glucose administration for hypoglycemia; techniques for cooling of exertional hyperthermia and heatstroke; recognition of acute stroke; the use of supplementary oxygen in acute stroke; early or first aid use of aspirin for chest pain; control of life- threatening bleeding through the use of tourniquets, haemostatic dressings, direct pressure, or pressure devices; the use of a compression wrap for closed extremity joint injuries; and temporary storage of an avulsed tooth. Additional summaries of scoping reviews are presented for the use of a recovery position, recognition of a concussion, and 6 other first aid topics. The First Aid Task Force has assessed, discussed, and debated the certainty of evidence on the basis of Grading of Recommendations, Assessment, Development, and Evaluation criteria and present their consensus treatment recommendations with evidence-to-decision highlights and identified priority knowledge gaps for future research. The 2020 International Consensus on Cardiopulmonary Resuscitation (CPR) and Emergency Cardiovascular Care (ECC) Science With Treatment Recommendations (CoSTR) is the fourth in a series of annual summary publications from the International Liaison Committee on Resuscitation (ILCOR). This 2020 CoSTR for first aid includes new topics addressed by systematic reviews performed within the past 12 months. It also includes updates of the first aid treatment recommendations published from 2010 through 2019 that are based on additional evidence evaluations and updates. As a result, this 2020 CoSTR for first aid represents the most comprehensive update since 2010.


Subject(s)
Cardiopulmonary Resuscitation , Emergency Medical Services , Out-of-Hospital Cardiac Arrest , Consensus , First Aid , Humans
11.
Dent Traumatol ; 36(5): 453-476, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32344468

ABSTRACT

BACKGROUND/AIM: It is crucial to store an avulsed tooth appropriately to preserve the viability of the periodontal ligament cells prior to replantation. The aim of this systematic review was to identify the best available evidence for the effectiveness of any technique available to laypeople for storing an avulsed tooth compared with storage in milk or saliva. METHODS: The following databases were searched (September 2019): Cochrane Library, MEDLINE, and Embase. Two reviewers independently considered trial eligibility, then extracted and analyzed data, and assessed the risk of bias. The certainty of the body of evidence was appraised according to the GRADE methodology. RESULTS: Out of 4118 references, 33 studies were included and reported 23 comparisons of which 10 were synthesized in a meta-analysis. The limited evidence available favors storing an avulsed tooth in Hank's balanced salt solution (pooled SMD 2.47, 95% CI [1.59;3.34], P < .00001), propolis solution (pooled SMD 1.73, 95% CI [1.12;2.33], P < .00001), oral rehydration salts (pooled SMD 4.16, 95% CI [2.10;6.23], P < .0001), rice water, and cling film compared with storage in milk. The cell viability rate was significantly lower in teeth stored in saline solutions (pooled SMD -4.35, 95% CI [-7.55;-1.14], P = .008), tap water, buttermilk, castor oil, GC Tooth Mousse, and turmeric extract than those stored in milk. There is insufficient evidence to recommend for or against temporary storage of an avulsed tooth in saliva compared with alternative solutions. The certainty of evidence was considered low to very low due to limitations in study design, indirect study populations and outcome measures, and imprecision. CONCLUSION: Although milk was shown to extend the periodontal ligament cell viability before replantation compared with saline or tap water, the following media have also demonstrated efficacy at preserving the cell viability: Hank's balanced salt solution, propolis, oral rehydration salts, rice water, and cling film.


Subject(s)
Organ Preservation Solutions , Tooth Avulsion , Animals , Cell Survival , Isotonic Solutions , Milk , Periodontal Ligament , Tooth Replantation
12.
Food Funct ; 10(8): 4674-4684, 2019 Aug 01.
Article in English | MEDLINE | ID: mdl-31292590

ABSTRACT

Wheat grain roller milling disrupts starch containing endosperm cell walls and extracts white flour. Many wheat based food processes involve simultaneous use of heat and water which then cause starch to gelatinize and enhance its digestibility. In this study, the impact of starch enclosure in intact endosperm cell walls on starch physicochemical properties and digestibility was investigated. Wheat kernels milled into coarse farina (average particle size: 705 µm) contained a substantial portion of intact cells and exhibited 15-30% lower Rapid Visco Analyzer peak viscosity readings than flour and fine farina (average particle size: 85 and 330 µm, respectively) since its higher level of intact cell walls limited the swelling of the enclosed starch. Xylanase use in situ substantially degraded coarse farina cell walls and increased their swelling and viscosifying potential. Following full gelatinization of the different samples, the starch in coarse farina was digested at a 40% lower rate in an in vitro gastrointestinal digestion assay, but still to a similar extent to that in fully gelatinized flour. This indicates that while wheat endosperm cell walls are permeable to pancreatic amylase, they can sufficiently slow down enzyme diffusion. When xylanase treatment was performed after starch gelatinization and pasting, the rates of starch digestion were similar for all samples evidencing that cell walls act as physical barriers to enzyme diffusion and thus retard its digestion. The present findings offer ways to produce wheat-based foods with sustained energy release benefits.


Subject(s)
Cell Wall/chemistry , Endosperm/chemistry , Food Handling/methods , Starch/chemistry , Triticum/chemistry , Biocatalysis , Cell Wall/metabolism , Digestion , Endo-1,4-beta Xylanases/chemistry , Endosperm/metabolism , Flour/analysis , Gelatin/chemistry , Gelatin/metabolism , Humans , Particle Size , Seeds/chemistry , Starch/metabolism , Triticum/metabolism , Viscosity , alpha-Amylases/chemistry
13.
ACS Omega ; 4(26): 22089-22100, 2019 Dec 24.
Article in English | MEDLINE | ID: mdl-31891089

ABSTRACT

Priming improves the seed germination rate and grain yield. Before this work was executed, little, if any, research has been reported on priming wheat for improving its nutritional properties. The impact of hydro-priming and osmo-priming using solutions with different water potentials on selected hydrolytic enzyme activities and their breakdown of starch, cell wall materials, and phytates during subsequent sprouting was studied here. A higher germination rate in the early growth stage of seedlings was found for hydro-primed or osmo-primed (-0.3, -0.6 MPa) grains. Hydro-primed sprouted grains had the longest radicles and coleoptiles and the highest hydrolytic enzyme activities. The latter lead to a 90% increase in reducing sugar, a 20% increase in water-extractable arabinoxylan, and an 8% decrease in phytate contents after 5 days of sprouting. This study thus offers opportunities for optimizing agricultural practice. The presence of different plant hormones and their concentrations are generally not affected by priming. However, the plant hormone concentrations in grains primed at -1.2 MPa and subsequently sprouted were lower than those in all other samples under study. The induction of too high osmotic stresses in these grains leads to disruption of the sprouting processes. Finally, it was for the first time found, based on the known biosynthesis pathways of wheat, that gibberellic acid (GA)20-oxidase in (primed) sprouted wheat is more active than GA3-oxidase and much more active than GA13-oxidase.

14.
Compr Rev Food Sci Food Saf ; 18(1): 305-328, 2019 Jan.
Article in English | MEDLINE | ID: mdl-33337026

ABSTRACT

Sprouting induces activation and de novo synthesis of hydrolytic enzymes that make nutrients available for plant growth and development. Consumption of sprouted grains is suggested to be beneficial for human health. Positive consumer perceptions about sprouted cereals have resulted in new food and beverage product launches. However, because there is no generally accepted definition of "sprouting," it is unclear when grains are to be called sprouted. Moreover, guidelines about how much sprouted grain material food products should contain to exert health benefits are currently lacking. Accordingly, there is no regulatory base to develop appropriate food labeling for "sprouted foods." This review describes the nutritional and technological properties of sprouted grains in relation to processing conditions and provides guidelines to optimize sprouting practices in order to maximize nutritive value. Relatively long sprouting times (3 to 5 days) and/or high processing temperatures (25 to 35 °C) are needed to maximize the de novo synthesis and/or release of plant bioactive compounds. Nutrient compositional changes resulting from sprouting are often associated with health benefits. However, supportive data from clinical studies are very scarce, and at present it is impossible to draw any conclusion on health benefits of sprouted cereals. Finally, grains sprouted under the above-mentioned conditions are generally unfit for use in traditional food processing and it is challenging to use sprouted grains as ingredients without compromising their nutrient content. The present review provides a basis for better defining what "sprouting" is, and to help further research and development efforts in this field as well as future food regulations development.

15.
Food Chem ; 264: 367-376, 2018 Oct 30.
Article in English | MEDLINE | ID: mdl-29853389

ABSTRACT

Chelation of iron and zinc in wheat as phytates lowers their bio-accessibility. Steeping and germination (15 °C, 120 h) lowered phytate content from 0.96% to only 0.81% of initial dry matter. A multifactorial experiment in which (steeped/germinated) wheat was subjected to different time (2-24 h), temperature (20-80 °C) and pH (2.0-8.0) conditions showed that hydrothermal processing of germinated (15 °C, 120 h) wheat at 50 °C and pH 3.8 for 24 h reduced phytate content by 95%. X-ray absorption near-edge structure imaging showed that it indeed abolished chelation of iron to phytate. It also proved that iron was oxidized during steeping, germination and hydrothermal processing. It was further shown that zinc and iron bio-accessibility were respectively 3 and 5% in wheat and 27 and 37% in hydrothermally processed wheat. Thus, hydrothermal processing of (germinated) wheat paves the way for increasing elemental bio-accessibility in whole grain-based products.


Subject(s)
Edible Grain/chemistry , Iron/chemistry , Phytic Acid/analysis , Triticum/growth & development , Zinc/chemistry , 6-Phytase/metabolism , Chelating Agents/chemistry , Germination , Hydrogen-Ion Concentration , Hydrolysis , Iron/metabolism , Phytic Acid/metabolism , Temperature , Triticum/chemistry , Triticum/metabolism , X-Ray Absorption Spectroscopy , Zinc/metabolism
16.
Plant Cell Environ ; 39(8): 1835-47, 2016 08.
Article in English | MEDLINE | ID: mdl-27038325

ABSTRACT

Several studies have suggested that the majority of iron (Fe) and zinc (Zn) in wheat grains are associated with phytate, but a nuanced approach to unravel important tissue-level variation in element speciation within the grain is lacking. Here, we present spatially resolved Fe-speciation data obtained directly from different grain tissues using the newly developed synchrotron-based technique of X-ray absorption near-edge spectroscopy imaging, coupling this with high-definition µ-X-ray fluorescence microscopy to map the co-localization of essential elements. In the aleurone, phosphorus (P) is co-localized with Fe and Zn, and X-ray absorption near-edge structure imaging confirmed that Fe is chelated by phytate in this tissue layer. In the crease tissues, Zn is also positively related to P distribution, albeit less so than in the aleurone. Speciation analysis suggests that Fe is bound to nicotianamine rather than phytate in the nucellar projection, and that more complex Fe structures may also be present. In the embryo, high Zn concentrations are present in the root and shoot primordium, co-occurring with sulfur and presumably bound to thiol groups. Overall, Fe is mainly concentrated in the scutellum and co-localized with P. This high resolution imaging and speciation analysis reveals the complexity of the physiological processes responsible for element accumulation and bioaccessibility.


Subject(s)
Edible Grain/metabolism , Iron/metabolism , Triticum/metabolism , Microscopy, Fluorescence , Plant Proteins/metabolism , X-Ray Absorption Spectroscopy
SELECTION OF CITATIONS
SEARCH DETAIL
...