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1.
Foods ; 12(13)2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37444354

RESUMO

Focus on local food production and supply chains has heightened in recent years, as evidenced and amplified by the COVID-19 pandemic. This study aimed to assess the suitability of soft red winter (SRW) wheat breeding lines for local artisan bakers interested in locally sourced, strong gluten wheat for bread. Seventy-six genotyped SRW wheat breeding lines were milled into whole wheat flour and baked into small loaves. Bread aroma, flavor, and texture were evaluated by a sensory panel, and bread quality traits, including sedimentation volume, dough extensibility, and loaf volume, were measured to estimate heritability. SE-HPLC was performed on white flour, and breeding lines were characterized for different protein fraction ratios. Heritability of loaf volume was moderately high (h2 = 0.68), while heritability of sedimentation volume, a much easier trait to measure, was slightly lower (h2 = 0.55). Certain protein fraction ratios strongly related to loaf volume had high heritability (h2 = 0.7). Even though only a moderate heritability estimate of dough extensibility was found in our study, high positive correlations were found between this parameter and sedimentation volume (r = 0.6) and loaf volume (r = 0.53). This low-input and highly repeatable parameter could be useful to estimate dough functionality characteristics. Flavor and texture heritability estimates ranged from 0.16 to 0.37, and the heritability estimate of aroma was not significantly different from zero. However, the sensorial characteristics were significantly correlated with each other, suggesting that we might be able to select indirectly for aroma by selecting for flavor or texture characteristics. From a genome-wide association study (GWAS), we identified six SNPs (single nucleotide polymorphisms) associated with loaf volume that could be useful in breeding for this trait. Producing high-quality strong gluten flour in our high rainfall environment is a challenge, but it provides local growers and end users with a value-added opportunity.

2.
Food Chem ; 405(Pt B): 135001, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36435111

RESUMO

The utilization of industrial hemp in food is gaining popularity. This study aimed to comprehensively investigate the impact of alkaline extraction-isoelectric precipitation (AE-IEP) and salt extraction (SE) dialysis on structural, functional properties and the volatile profile of hemp protein isolate (HPI). A higher protein content (97.21%) in SE extracted HPI (SE-HPI) was obtained than the AE-IEP extracted HPI (93.37%). In particular, protein subunit composition, structural properties were strongly influenced by the extraction methods. For example, SE-HPI exhibited a larger percentage of albumin (46.53%) and a lower amount of ß-sheet (52.65%) than its counterpart (albumin 20.92%, ß-sheet 54.46%). Consequently, SE-HPI showed the higher solubility, emulsion activity, and thermal stability. Interestingly, the volatile profile of the proteins showed that SE-HPI exhibited a lower number (21) of volatile compounds when compared to its counterpart (25). This study highlights the importance of establishing the relationships between extraction methods and functional attributes of HPI.


Assuntos
Cannabis , Diálise Renal , Cloreto de Sódio na Dieta , Cloreto de Sódio , Albuminas
3.
Food Chem ; 382: 132570, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35245760

RESUMO

The utilization of beans (Phaseolus vulgaris L.) is hindered by unpleasant flavors, low macronutrients digestibility, and long cooking time. The pre-thermally treated beans can overcome these limitations. Therefore, the effect of thermal methods (moist-heat and dry-heat) and bean market classes (black, navy, kidney, and pinto) on functional properties and digestibility of bean flours were compared to raw counterparts. Within bean class, moist-heated samples showed increased water-holding capacities of 2.54-2.87 g H2O/g sample and starch/protein digestibility whereas dry-heated samples showed enhanced flavor profile and increased oil-holding capacities of 1.04-1.14 g oil/g sample. Among bean classes, moist-heated kidney bean flour showed the highest water-holding capacity of 2.87 g H2O/g sample and starch/protein digestibility while dry-heated pinto bean flour had the highest oil-holding capacity of 1.14 g oil/g sample. The current result may provide a basis for the development of pre-thermally treated legume flours and facilitate their applications.


Assuntos
Phaseolus , Farinha/análise , Nutrientes , Phaseolus/química , Sementes/química , Amido/química
4.
Food Funct ; 12(19): 8907-8919, 2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34378612

RESUMO

The objective of this study was to investigate the impact of protein type (sodium caseinate and pea protein isolate) and protein to sugar beet pectin mixing ratio (5 : 1 and 2 : 1) on complex coacervate formation, as well as the impact of the finishing technology (freeze-drying and spray-drying) for improving the viability of encapsulated Lactobacillus rhamnosus GG (LGG) in complex coacervates during simulated sequential gastrointestinal (GI) digestion. The physicochemical properties of LGG encapsulated microcapsules in liquid and powder form were evaluated. The state diagram and ζ-potential results indicated that pH 3.0 was the optimum pH for coacervate formation in the current systems. Confocal laser scanning microscopy (CLSM), viscoelastic analysis, and Fourier transform infrared spectroscopy (FTIR) confirmed that the gel-like network structure of the complex coacervates was successfully formed between the protein and SBP at pH 3.0 through electrostatic interaction. In terms of physiochemical properties and viability of LGG encapsulated in the microcapsule powder, the drying method played a crucial role on particle size, microstructure and death rate of encapsulated LGG during simulated sequential GI digestion compared to protein type and biopolymer mixing ratio. For example, the microstructure of spray-dried microcapsules exhibited smaller spherical particles with some cavities, whereas the larger particle size of freeze-dried samples showed a porous sponge network structure with larger particle sizes. As a result, spray-dried LGG microcapsules generally had a lower death rate during simulated sequential gastrointestinal digestion compared to their freeze-dried counterparts. Among all samples, spray-dried PPI-SBP microcapsules demonstrated superior performance against cell loss and maintained more than 7.5 log CFU per g viable cells after digestion.


Assuntos
Digestão , Pectinas/química , Probióticos , Cápsulas , Composição de Medicamentos , Liofilização , Humanos , Viabilidade Microbiana , Espectroscopia de Infravermelho com Transformada de Fourier , Secagem por Atomização
5.
Food Chem ; 344: 128699, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33261996

RESUMO

The objective of this study was to establish the impacts of supercritical fluid extraction (SFE) processing on the physicochemical properties of pea flour and the structure of isolated pea starch. A significant (p < 0.05) increase in protein content and reduction in several pasting and thermal parameters as measured by rapid visco-analyzer and differential scanning calorimeter were observed after SFE. Additionally, SFE increased starch digestibility as determined by an in vitro starch digestion assay. An increased amylopectin content and crystallinity along with the loss of double helix content was supported by size exclusion chromatography and FT-IR data, respectively. X-ray diffraction and scanning electron microscopy showed minimal alterations of starch, by SFE, in long-range crystalline and morphological structure of starch granules, respectively. The data demonstrated SFE influenced the physicochemical and structural characteristics of pea starch. These outcomes illustrated that SFE might be a green and novel technology for starch modification.


Assuntos
Dióxido de Carbono/química , Fenômenos Químicos , Etanol/química , Pisum sativum/química , Amido/química , Amido/isolamento & purificação , Farinha
6.
Food Chem ; 332: 127422, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32623129

RESUMO

During wheat cultivation, glyphosate-based herbicides are recommended to be applied a week prior to harvest during the ripe stage of physiological maturity. However, some grains may not be at this physiological stage due to non-uniform maturation within the field. The goal of this study was to determine the effect of glyphosate-based herbicide timing on the chemistry of wheat gluten proteins and shikimic acid accumulation. The results of the study indicate that pre-harvest glyphosate application does not impact the amino acid composition, protein secondary structure or gluten protein composition. However, pre-harvest glyphosate application decreased the molecular weight of SDS extractable and unextractable proteins, and significantly increased the amount of shikimic acid accumulation, especially when applied early. Thus, this study indicates that pre-harvest use of glyphosate-based herbicides can cause significant differences in wheat protein chemistry and shikimic acid levels, especially when applied earlier than recommended, emphasizing the importance of timely application.


Assuntos
Glicina/análogos & derivados , Herbicidas/farmacologia , Proteínas de Plantas/metabolismo , Ácido Chiquímico/metabolismo , Triticum/efeitos dos fármacos , Aminoácidos/análise , Aminoácidos/metabolismo , Glutens/análise , Glutens/metabolismo , Glicina/farmacologia , Proteínas de Plantas/análise , Ácido Chiquímico/análise , Triticum/química , Triticum/crescimento & desenvolvimento , Triticum/metabolismo , Glifosato
7.
J Food Biochem ; 44(8): e13330, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32557639

RESUMO

The objective of this study was to determine if the pre-harvest glyphosate application time affects the chemistry of wheat starch. Glyphosate was sprayed at the ripe stage (recommended) and the soft dough stage (early application) of hard red spring wheat. Wheat kernel samples were collected before application and every 3 days until harvest, after which different starch characteristics were analyzed. The results indicate that glyphosate timing does not impact the spatial distribution or morphology of starch granules, as well as the percentage or molecular weight of amylose and amylopectin. However, thermal characteristics of wheat starch, especially when glyphosate was applied at the soft dough stage, showed significant differences. A decrease in the average amylopectin chain length and differences in the proportion of short-, medium-, and long-chain amylopectin was also observed. Overall, this study shows that the pre-harvest application of glyphosate can affect wheat starch chemistry, especially if applied earlier than recommended. PRACTICAL APPLICATIONS: Glyphosate is the most commonly used herbicide in the world, and it is sometimes used pre-harvest during wheat cultivation. The recommended time of application is 7 days prior to harvest when the crops are in the ripe stage of physiological maturity. However, some crops may not be at this stage during application due to non-uniform maturation in the field. The goal of this work was to determine the effect of glyphosate application time (recommended/ripe stage vs. early/soft dough stage) on wheat starch chemistry. The results show that the starch chain length characteristics and thermal behavior are impacted, especially if applied early. Thus, this study shows the importance of timely application to avoid effects on starch chemical properties, which in return could impact starch functionality in food systems. This information is critical in the field of agriculture and to our knowledge this study is one of the first in this area.


Assuntos
Amido , Triticum , Amilopectina , Glicina/análogos & derivados , Glifosato
8.
Food Res Int ; 131: 109045, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32247471

RESUMO

In the current study, the impact of alkaline extraction pH (8.5, 9.0, and 9.5) on chemical composition, molecular structure, solubility and aromatic profile of PPI was investigated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), the quantification of free sulfhydryl group and disulfide bond contents, size exclusion chromatography with multi-angle static light scattering and refractive index (SEC-MALS-RI), circular dichroism (CD) spectroscopy, and headspace solid phase micro extraction gas chromatography-mass spectroscopy (HS-SPME-GC-MS). We found that protein recovery yield increased from 49.20% to 57.56% as the alkaline extraction pH increased from 8.5 to 9.5. However, increasing the extraction pH promoted the formation of protein aggregates which decreased the percent protein solubility although there was no influence on protein secondary structure. PPI extracted at pH 9.0 possessed the lowest beany flavor as revealed by the selected six beany flavor markers including alcohols, aldehydes, ketones and pyrazine. The lowest lipoxygenase activity at pH 9.0 may contribute to the least beany flavor in PPI. Therefore, pH 9.0 was found to be the optimal condition for preparing premium PPI in terms of yield, functionality, and aromatic profile using alkaline extraction-isoelectric precipitation process. The findings could have fundamental implications for the preparation and utilization of pea proteins in food applications.


Assuntos
Concentração de Íons de Hidrogênio , Proteínas de Ervilha/química , Proteínas de Ervilha/isolamento & purificação , Pisum sativum/química , Dicroísmo Circular , Dissulfetos/análise , Manipulação de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Lipoxigenase/metabolismo , Odorantes/análise , Estrutura Secundária de Proteína , Microextração em Fase Sólida , Solubilidade , Compostos de Sulfidrila/análise , Paladar , Compostos Orgânicos Voláteis/análise
9.
Soft Matter ; 16(7): 1877-1887, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-31994592

RESUMO

Sodium alginate hydrogel particles coated with cationic biopolymers have been shown to be one of the promising means for probiotic encapsulation and protection. In this study, we aimed to systematically explore the effect of molecular weight of chitosan coating on the functional performance of sodium alginate hydrogel particles for improving the viability of Lactobacillus rhamnosus GG (LGG). We first electrostatically deposited three different molecular weights of chitosan coatings, i.e., chitosan oligosaccharide (COS), low molecular weight chitosan (LMW-chitosan) and medium molecular weight chitosan (MMW-chitosan) on sodium alginate hydrogel particles. Both SEM and FTIR results indicated that chitosan was successfully deposited onto the surface of the hydrogel particles. We then evaluated the effect of chitosan MW on the viability of LGG encapsulated in the hydrogels during long-term storage and simulated gastrointestinal digestion. Among them, the hydrogel particles coated with COS prevented the viability loss of LLG during long-term storage at different temperatures (4, 25 and 37 °C). However, we did not find any improvement in the viability of the encapsulated LGG by all three chitosan coatings during simulated digestion.


Assuntos
Quitosana/química , Composição de Medicamentos , Lacticaseibacillus rhamnosus/efeitos dos fármacos , Probióticos/farmacologia , Alginatos/química , Alginatos/farmacologia , Quitosana/farmacologia , Digestão/efeitos dos fármacos , Trato Gastrointestinal/efeitos dos fármacos , Humanos , Hidrogéis/química , Hidrogéis/farmacologia , Lacticaseibacillus rhamnosus/crescimento & desenvolvimento , Peso Molecular , Probióticos/química
10.
J Food Prot ; 83(5): 836-843, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31928423

RESUMO

ABSTRACT: Recent outbreaks traced to contaminated flour have created a need in the milling industry for a process that reduces pathogens in wheat while maintaining its functional properties. Vacuum steam treatment is a promising technology for treatment of low-moisture foods. Traditional thermal treatment methods can compromise wheat functionality due to high temperatures; thus, maintaining the functional quality of the wheat protein was critical for this research. The objective of this study was to evaluate the effect of vacuum steam treatment of hard red spring (HRS) wheat kernels on final flour quality and the overall efficacy of vacuum stream treatment for reducing pathogens on HRS wheat kernels. HRS wheat samples were treated with steam under vacuum at 65, 70, 75, and 85°C for 4 and 8 min. Significant changes in dough and baked product functionality were observed for treatments at ≥70°C. Treatment time had no significant effect on the qualities evaluated. After determining that vacuum steam treatment at 65°C best preserved product quality, HRS wheat was inoculated with Escherichia coli O121 and Salmonella Enteritidis PT 30 and processed at 65°C for 0, 2, 4, 6, or 8 min. The treatments achieved a maximum average reduction of 3.57 ± 0.33 log CFU/g for E. coli O121 and 3.21 ± 0.27 log CFU/g for Salmonella. Vacuum steam treatment could be an effective pathogen inactivation method for the flour milling industry.


Assuntos
Escherichia coli Êntero-Hemorrágica/crescimento & desenvolvimento , Farinha , Manipulação de Alimentos/métodos , Salmonella enteritidis/crescimento & desenvolvimento , Triticum , Contagem de Colônia Microbiana , Farinha/microbiologia , Farinha/normas , Microbiologia de Alimentos , Vapor , Triticum/microbiologia , Vácuo
11.
J Agric Food Chem ; 68(2): 503-511, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31869217

RESUMO

Due to nonuniform maturation, some plants may not be at the recommended stage of maturity when preharvest glyphosate is applied. The objective of this study was to determine how preharvest glyphosate timing affects wheat starch physicochemical properties. Two wheat cultivars were grown in three locations, and glyphosate was applied at the soft dough stage (early application) and the ripe stage (commercial standard). Upon harvest, starch chemical characteristics were studied. The proportion of B-type starch granules was lower in treated samples, although the starch molecular weight was not affected. Rapidly digestible starch content was highest when glyphosate was applied at the ripe stage, and lowest in the control, and vice versa for slowly digestible starch. Additionally, flour pasting viscosity was significantly higher in samples treated at the soft dough stage. Overall, the effects on wheat starch physicochemical characteristics were more pronounced when glyphosate was applied at the soft dough stage of maturity.


Assuntos
Glicina/análogos & derivados , Herbicidas/farmacologia , Amido/química , Triticum/efeitos dos fármacos , Triticum/crescimento & desenvolvimento , Fenômenos Químicos , Glicina/farmacologia , Sementes/química , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Amido/metabolismo , Triticum/química , Triticum/metabolismo , Glifosato
12.
Food Chem ; 307: 125536, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31654950

RESUMO

This study aimed to develop an alternative method named state diagram to identify boundary formation pH for complex coacervates between pea protein isolate (PPI) and sugar beet pectin (SBP) at concentrated solutions (~2.0 wt%). The effects of pH (7-2) and PPI-SBP mixing ratios (1:1-20:1) on coacervates formation were investigated by state diagram, zeta-potential, rheological, and phase composition analysis. Isothermal titration calorimetry, scanning electron microscopy, and Fourier transform infrared spectroscopy were employed to elucidate thermodynamic behaviors, non-covalent bonding of coacervates, and microstructure of coacervates. We demonstrate that state diagram can explicitly identify the three characteristic pH values (pHφ1, pHopt, and pHφ2) at which recognizable transitions take place in concentrated colloids solutions. The mixing ratio dependent of pHφ1 increased to pH 5.5 as PPI-SBP mixing ratio increased to 20:1. The pHopt was recognized at the net charge neutrality or the highest storage modulus of the mixed colloids solutions.


Assuntos
Proteínas de Ervilha/química , Pectinas/química , Termodinâmica , Beta vulgaris/química , Calorimetria , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier
13.
Foods ; 8(12)2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31842464

RESUMO

Ancient grains have gained renewed interest in the last few years due to their perceived nutritional benefits. The goal of this study was to examine the presence of celiac epitopes in different ancient grains and determine differences in the gliadin protein profile of such grains. To investigate celiac epitopes, an untargeted mass spectrometric method was used, and the gliadin protein profile was studied using reverse phase-HPLC. Our findings show that celiac epitopes can be detected in wheat-related ancient grains, such as einkorn, emmer, and Kamut, indicating that these ancient grains have the potential to elicit the immune response associated with celiac disease. Additionally, the results showed that the gliadin protein composition is significantly different between ancient grain species, which could result in varying functional properties in end-use applications.

14.
Food Funct ; 10(10): 6840-6850, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31580364

RESUMO

This research aims to study antioxidative activities of polar solvent extractable phenolic compounds from yellow peas with different germination times against oil-in-water emulsion oxidation. After germination (0, 2, 4, and 6 days), soluble free and polar soluble bound phenolic compounds were extracted and their antioxidative activity was evaluated using stripped soybean oil (SSO)-in-water emulsions. Liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS) and size-exclusion chromatography with multiangle-light-scattering and refractive-index detection (SEC-MALS-RI) were employed to analyze the phenolic composition and molar mass, respectively. Antioxidative activities of soluble free phenolic compounds increased in the SSO-in-water emulsion system, while those of polar soluble bound phenolic compounds decreased with germination. On the basis of chemometric analysis, pratensein (2), phloridzin (4), quercetin (9), sayanedine (12), hesperetin (13), glyzaglabrin (14), and pinocembrin (15) were speculated as the pivotal phenolic compounds responsible for the hydrogen donating capacity. Additionally, decreased molecular weight of soluble bound phenolic compounds was accompanied by the reduction of antioxidative activity in SSO-in-water emulsions indicating that the moieties of polar soluble bound phenolic compounds also have an important impact on the antioxidative activity of phenolic compounds.


Assuntos
Germinação , Oxirredução , Fenóis/química , Pisum sativum/química , Antioxidantes , Cromatografia em Gel , Cromatografia Líquida , Emulsões , Pisum sativum/metabolismo , Extratos Vegetais/química , Óleo de Soja , Espectrometria de Massas por Ionização por Electrospray , Fatores de Tempo
15.
Food Chem ; 278: 665-673, 2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-30583427

RESUMO

Recently, there is a strong interest in incorporation of pea protein as a preferred alternative to animal protein into protein-fortified food. However, the utilization of pea protein as a food ingredient has been largely limited because of its poor functionality. The aim of this study was to understand if solid dispersion-based spray-drying processing could be applied to enhance the solubility and mitigate off-flavour in pea protein isolate (PPI). The influence of amorphous matrix carrier type (gum arabic and maltodextrin), and PPI to carrier ratio (90:10-60:40) on physical properties, solubility, and off-flavour profile of PPI was investigated. The results demonstrated the possible mechanism by which factors such as surface area/volume ratio, hydrogen bonding, and electrostatic interaction between PPI and carriers enhance PPI solubility. Meanwhile, beany flavours were mitigated through the unfolding of secondary structure of PPI by forming solid dispersions with gum arabic or maltodextrin during spray-drying.


Assuntos
Dessecação/métodos , Proteínas de Ervilha/metabolismo , Goma Arábica/química , Ligação de Hidrogênio , Proteínas de Ervilha/química , Polissacarídeos/química , Estrutura Secundária de Proteína , Solubilidade , Eletricidade Estática
16.
J Agric Food Chem ; 66(24): 6179-6187, 2018 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-29860843

RESUMO

Our recent study found that antioxidative activity of phenolic compounds extracted from germinated chickpea was boosted in both in vitro assays and oil-in-water emulsions [ Xu et al. Food Chem. 2018 , 250 , 140 ]. The purpose of this study was to elucidate the mechanism by which germination enhances the antioxidative activity of the phenolic compounds extracted from chickpea. Liquid chromatography coupled with electrospray-ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS) and size-exclusion chromatography with multiangle-light-scattering and refractive-index detection (SEC-MALS-RI) were employed to evaluate the phenolic composition of soluble phenolic compounds (free and bound) and molar masses of soluble bound phenolic compounds, respectively, over 6 days of germination. According to principal-component analysis of the interrelationship between germination time and phenolic composition, it is revealed that protocatechuic acid 4- O-glucoside and 6-hydroxydaidzein played a pivotal role in the soluble free phenolic compounds, whereas gentisic acid and 7,3',4'-trihydroxyflavone were important in the soluble bound phenolic compounds. Molar masses of soluble bound phenolic compounds were increased after 6 days of germination. Protective and dual antioxidative effects were proposed to explicate how the antioxidative activity of soluble bound phenolic compounds in oil-in-water emulsions was improved with germination.


Assuntos
Antioxidantes/química , Cicer/química , Cicer/crescimento & desenvolvimento , Extratos Vegetais/química , Antioxidantes/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Flavonoides/química , Flavonoides/isolamento & purificação , Germinação , Extratos Vegetais/isolamento & purificação , Sementes/química , Sementes/crescimento & desenvolvimento , Espectrometria de Massas por Ionização por Electrospray
17.
Chemosphere ; 186: 695-701, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28820992

RESUMO

Dissolved organic nitrogen (DON) from animal wastes can contribute to pollution of surface waters. Bioavailable DON (ABDON) is a portion of DON utilized by algae with or without bacteria. This study determined DON and ABDON levels in animal wastewater collected from two different sources: an animal feedlot wastewater storage tank and a sheep wastewater storage lagoon. Inocula for the ABDON bioassays were comprised of individual species and several combinations involving two algae (Chlamydomonas reinhardtii and Chlorella vulgaris) and a mixed liquor suspended solids (MLSS) bacterial culture. The ratio of initial DON to initial total dissolved nitrogen was 18% in the feedlot wastewater samples and 70% in the lagoon wastewater samples. The results showed that between 1.6 and 4.5 mg-NL-1 DON (45-79% of initial DON) in the feedlot samples and between 3.4 and 7.5 mg-NL-1 DON (36%-79% of initial DON) in the lagoon samples were bioavailable with the inocula tested. These results suggest that when considering eutrophication potential of livestock wastewater, organic nitrogen should be included in addition to the obvious culprits, ammonia and nitrate.


Assuntos
Criação de Animais Domésticos/métodos , Nitrogênio/análise , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Poluentes Químicos da Água/análise , Amônia , Animais , Bactérias , Chlorella vulgaris , Monitoramento Ambiental , Eutrofização , Nitratos , Águas Residuárias/estatística & dados numéricos
18.
Water Res ; 92: 44-51, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26841227

RESUMO

Dissolved organic nitrogen (DON) and its biodegradability in treated wastewater have recently gained attention due to increased regulatory requirements on effluent quality to protect receiving waters. Laboratory scale chemostat experiments were conducted at 9 different solids retention times (SRTs) (0.3, 0.7, 2, 3, 4, 5, 7, 8, and 13 days) to examine whether SRT could be used to control DON, biodegradable DON (BDON), and DON biodegradability (BDON/DON) levels in treated wastewater. Results indicated no trend between effluent DON and SRTs. Effluent BDON was comparable for SRTs of 0.3-4 days and had a decreasing trend with SRT after that. Effluent DON biodegradability (effluent BDON/effluent DON) ranging from 23% to 59% tended to decrease with SRT. Chemostat during longer SRTs, however, was contributing to non-biodegradable DON (NBDON) and this fraction of DON increased with SRT above 4 days. Model calibration results indicated that ammonification rate, and growth rates for ordinary heterotrophs, ammonia oxidizing bacteria and nitrite oxidizing bacteria were not constants but have a decreasing trend with increasing SRT. This study indicates the benefit of high SRTs in term of producing effluent with less DON biodegradability leading to relatively less oxygen consumption and nutrient support in receiving waters.


Assuntos
Nitrogênio/análise , Águas Residuárias/química , Purificação da Água/métodos , Amônia/análise , Biodegradação Ambiental , Análise da Demanda Biológica de Oxigênio , Compostos Orgânicos/análise , Compostos Orgânicos/isolamento & purificação , Solubilidade , Fatores de Tempo , Eliminação de Resíduos Líquidos
19.
J Agric Food Chem ; 62(40): 9819-31, 2014 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-25177767

RESUMO

Grain protein composition determines quality traits, such as value for food, feedstock, and biomaterials uses. The major storage proteins in sorghum are the prolamins, known as kafirins. Located primarily on the periphery of the protein bodies surrounding starch, cysteine-rich ß- and γ-kafirins may limit enzymatic access to internally positioned α-kafirins and starch. An integrated approach was used to characterize sorghum with allelic variation at the kafirin loci to determine the effects of this genetic diversity on protein expression. Reversed-phase high performance liquid chromatography and lab-on-a-chip analysis showed reductions in alcohol-soluble protein in ß-kafirin null lines. Gel-based separation and liquid chromatography-tandem mass spectrometry identified a range of redox active proteins affecting storage protein biochemistry. Thioredoxin, involved in the processing of proteins at germination, has reported impacts on grain digestibility and was differentially expressed across genotypes. Thus, redox states of endosperm proteins, of which kafirins are a subset, could affect quality traits in addition to the expression of proteins.


Assuntos
Endosperma/química , Proteínas de Plantas/análise , Sorghum/química , Cromatografia Líquida de Alta Pressão/métodos , Eletroforese em Gel de Poliacrilamida , Genótipo , Glutarredoxinas/metabolismo , Dispositivos Lab-On-A-Chip , Mutação , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Prolaminas/metabolismo , Proteômica , Proteínas de Armazenamento de Sementes/metabolismo , Sorghum/genética , Espectrometria de Massas em Tandem , Tiorredoxinas/metabolismo
20.
Carbohydr Polym ; 111: 273-9, 2014 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-25037352

RESUMO

Soybean meal was used to isolate resistant starch and produce nanoparticles, which could be potential coating materials for colonic nutrient and drug deliveries. The nanoparticles were in 40 ± 33.2 nm ranges. These nanoparticles were stable under simulated human physiological conditions. The degrees of dissolution in both stomach and intestinal conditions were less than 30%. Furthermore, the nanoparticles were less susceptible to pancreatic enzymatic digestion (20%), which was also evidenced by the co-existence of B-type crystalline pattern. In addition to the dissolution and digestion studies in the upper gastrointestinal tract, the nanoparticles were subjected to in vitro fermentation by Bifidobacterium brevis and Lactobacillus casei. Both species showed an increase in growth and activity, while producing short chain fatty acids: acetate, propionate, and butyrates in varying amounts. Overall this study clearly demonstrated a novel method that can be used for colon-specific delivery of bioactive compounds such as drugs and nutrients.


Assuntos
Colo/enzimologia , Sistemas de Liberação de Medicamentos , Glycine max/química , Nanopartículas/metabolismo , Amido/metabolismo , Bifidobacterium/enzimologia , Ácidos Graxos Voláteis/biossíntese , Humanos , Lacticaseibacillus casei/enzimologia , Modelos Biológicos , Nanopartículas/administração & dosagem , Nanopartículas/química , Amido/administração & dosagem , Amido/química , Estômago/enzimologia
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