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1.
Food Chem ; 362: 130236, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34111695

RESUMO

Three different proteinaceous biopolymers, namely, egg white protein (EWP), soy protein isolate (SPI) and corn protein isolate (CPI) were used as protective shell materials to encapsulate micronutrients via an ultrasonic encapsulation technique. It was found that the physicochemical properties of the three protein-based matrices, including surface/total thiol (-SH) content, surface activity and denaturation temperature were the key factors that influenced the shell formation and stability. The EWP and CPI-shelled microcapsules reduced the degradation of the encapsulated vitamins by 20% and 40% after exposure to heating and UV-light irradiation. A double emulsion technique was further developed to co-encapsulate both oil- (vitamin A and D) and water-soluble (vitamin B, C and minerals) micronutrients. In-vitro digestion study showed that the proteinaceous microcapsules enable a sustained release of micronutrients, demonstrating their potential for food fortification applications.


Assuntos
Cápsulas/química , Micronutrientes/administração & dosagem , Proteínas de Plantas/química , Cápsulas/administração & dosagem , Emulsões/química , Proteínas de Soja/química , Propriedades de Superfície , Vitaminas/administração & dosagem , Vitaminas/química , Zea mays/química
2.
Molecules ; 26(11)2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34073001

RESUMO

The effects of two types of biochar on corn production in the Mediterranean climate during the growing season were analyzed. The two types of biochar were obtained from pyrolysis of Pinus pinaster. B1 was fully pyrolyzed with 55.90% organic carbon, and B2 was medium pyrolyzed with 23.50% organic carbon. B1 and B2 were supplemented in the soil of 20 plots (1 m2) at a dose of 4 kg/m2. C1 and C2 (10 plots each) served as control plots. The plots were automatically irrigated and fertilizer was not applied. The B1-supplemented plots exhibited a significant 84.58% increase in dry corn production per square meter and a 93.16% increase in corn wet weight (p << 0.001). Corn production was no different between B2-supplemented, C1, and C2 plots (p > 0.01). The weight of cobs from B1-supplemented plots was 62.3%, which was significantly higher than that of cobs from C1 and C2 plots (p < 0.01). The grain weight increased significantly by 23% in B1-supplemented plots (p < 0.01) and there were no differences between B2-supplemented, C1, and C2 plots. At the end of the treatment, the soil of the B1-supplemented plots exhibited increased levels of sulfate, nitrate, magnesium, conductivity, and saturation percentage. Based on these results, the economic sustainability of this application in agriculture was studied at a standard price of €190 per ton of biochar. Amortization of this investment can be achieved in 5.52 years according to this cost. Considering the fertilizer cost savings of 50% and the water cost savings of 25%, the amortization can be achieved in 4.15 years. If the price of biochar could be reduced through the CO2 emission market at €30 per ton of non-emitted CO2, the amortization can be achieved in 2.80 years. Biochar markedly improves corn production in the Mediterranean climate. However, the amortization time must be further reduced, and enhanced production must be guaranteed over the years with long term field trials so that the product is marketable or other high value-added crops must be identified.


Assuntos
Agricultura/métodos , Carvão Vegetal/farmacologia , Zea mays/crescimento & desenvolvimento , Dióxido de Carbono/análise , Carvão Vegetal/metabolismo , Clima , Produtos Agrícolas/efeitos dos fármacos , Grão Comestível/química , Fertilizantes , Região do Mediterrâneo , Óxido Nitroso/análise , Solo , Zea mays/química
3.
Food Chem ; 361: 129901, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34082384

RESUMO

A simple electrochemical immunosensor based on nitrogen-doped graphene and polyamide-amine (GN-PAM) composites was proposed for the detection of the CP4-EPSPS protein in genetically modified (GM) crops. In this immunosensor, the amplification of the detection signal was realized through antibodies labeled with gold nanoparticles (AuNPs). The electrochemical responses of the immunosensor were linear (R2 = 0.9935 and 0.9912) when the GM soybean RRS and maize NK603 content ranged from 0.025% to 1.0% and 0.05% to 1.5%, respectively. The limits of detection for the GM soybean RRS and maize NK603 were as low as 0.01% and 0.03%, respectively. The immunosensor also exhibited high specificity, and satisfactory stability, reproducibility, and accuracy. Our findings indicated that the constructed immunosensor provides a new approach for the sensitive detection of the CP4-EPSPS protein. Notably, the sensor may be applied to other proteins or pathogenic bacteria by simply changing the antibodies, and may also be used for multi-component analysis.


Assuntos
3-Fosfoshikimato 1-Carboxiviniltransferase/genética , Produtos Agrícolas/genética , Imunoensaio/métodos , Plantas Geneticamente Modificadas/genética , Anticorpos Monoclonais/química , Produtos Agrícolas/química , Técnicas Eletroquímicas , Ouro/química , Grafite/química , Limite de Detecção , Nanopartículas Metálicas/química , Plantas Geneticamente Modificadas/química , Poliaminas/química , Reprodutibilidade dos Testes , Soja/química , Soja/genética , Zea mays/química , Zea mays/genética
4.
Food Chem ; 358: 129858, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33933983

RESUMO

The effect of sonication temperature on the structures and digestion behaviour of corn starch (CS, A-type), potato starch (PtS, B-type), and pea starch (PS, C-type) was investigated. For CS, sonication temperature resulted in a rough surface, decreased apparent amylose content, gelatinization enthalpy and gelatinization degree, increased short-range orders, long-range orders, retrogradation degree and resistant starch content. For PtS, sonication temperature led to a coarser surface with scratches, increased apparent amylose content and gelatinization degree, decreased short-range orders, long-range orders, gelatinization enthalpy, retrogradation degree, and resistant starch content. For PS, sonication temperature showed partial disintegration on surface, increased gelatinization degree, decreased apparent amylose content, short-range orders, long-range orders, gelatinization enthalpy, retrogradation degree and resistant starch content. This study suggested that starch digestion features could be controlled by the crystalline pattern of starch used and the extent of sonication temperature, and thus were of value for rational control of starch digestion features.


Assuntos
Ervilhas/química , Solanum tuberosum/química , Amido/química , Amido/farmacocinética , Zea mays/química , Amilose/análise , Amilose/química , Digestão , Gelatina/química , Sonicação , Temperatura
5.
Food Chem ; 358: 129813, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33940286

RESUMO

To investigate the impact of arabinoxylan (AX) on the physical and oxidative stability of oil-in-water emulsions, AX from wheat bran, corn bran, rice bran, or rye bran was incorporated into the production of whey protein isolate-stabilised emulsions. Decreased interfacial charge and increased mean particle diameters were recorded in all fresh emulsions with 0.1%-0.5% AX, as recorded by the ζ-potential and particle size measurement, indicating the adsorption of AX onto the oil droplets. No phase separation was observed in all emulsions with ≤0.3% AX after 14-day storage in dark. Spectrophotometric analysis demonstrated that all AX lowered the peroxide value and thiobarbituric acid reactive substance concentration in emulsions, with AX from rice bran being slightly more effective. Consequently, AX has the potential to be used as a natural interfacial antioxidant in emulsions, and the antioxidant capacity of AX varies with its source.


Assuntos
Emulsões/química , Lipídeos/química , Xilanos/química , Adsorção , Antioxidantes/química , Fibras na Dieta , Oryza/química , Oxirredução , Tamanho da Partícula , Secale/química , Substâncias Reativas com Ácido Tiobarbitúrico/química , Água/química , Zea mays/química
6.
Int J Biol Macromol ; 182: 701-711, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33862072

RESUMO

A study was carried out to investigate the characterization of a novel Aspergillus sulphureus JCM01963 xylanase (AS-xyn10A) with a carbohydrate binding module (CBM) and its application in degrading alkali pretreated corncob, rapeseed meal and corn stover alone and in combination with a commercial cellulase. In this study, the 3D structure of AS-xyn10A, which contained a CBM at C-terminal. AS-xyn10A and its CBM-truncated variant (AS-xyn10A-dC) was codon-optimized and over-expressed in Komagaella phaffii X-33 (syn. Pichia pastoris) and characterized with optimal condition at 70 °C and pH 5.0, respectively. AS-xyn10A displayed high activity to xylan extracted from corn stover, corncob, and rapeseed meal. The concentration of hydrolyzed xylo-oligosaccharides (XOSs) reached 1592.26 µg/mL, 1149.92 µg/mL, and 621.86 µg/mL, respectively. Xylobiose was the main product (~70%) in the hydrolysis mixture. AS-xyn10A significantly synergized with cellulase to improve the hydrolysis efficiency of corn stover, corncob, and rapeseed meal to glucose. The degree of synergy (DS) was 1.32, 1.31, and 1.30, respectively. Simultaneously, XOSs hydrolyzed with AS-xyn10A and cellulase was improved by 46.48%, 66.13% and 141.45%, respectively. In addition, CBM variant decreased the yields of xylo-oligosaccharide and glucose in rapeseed meal degradation. This study provided a novel GH10 endo-xylanase, which has potential applications in hydrolysis of biomass.


Assuntos
Aspergillus/enzimologia , Celulase/metabolismo , Dissacarídeos/metabolismo , Endo-1,4-beta-Xilanases/metabolismo , Proteínas Fúngicas/metabolismo , Biomassa , Brassica napus/química , Celulase/química , Endo-1,4-beta-Xilanases/química , Estabilidade Enzimática , Proteínas Fúngicas/química , Hidrólise , Ligação Proteica , Especificidade por Substrato , Zea mays/química
7.
Toxins (Basel) ; 13(5)2021 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-33921990

RESUMO

This study investigated the natural incidence of deoxynivalenol (DON) in corn and corn products from corn-producing districts of Punjab, Pakistan. The analysis was carried out using high performance liquid chromatography (HPLC) with UV detector and immunoaffinity cleanup columns. The detection limit (LOD) and limit of quantification were 25 and 50 µg/kg, respectively. A total of 1220 samples of corn and corn products were analyzed to detect DON, and 539 (44.2%) samples were observed to be contaminated with DON (n ≥ LOD). Furthermore, 92 (7.5%) samples of corn and corn products had DON levels that were higher than the proposed limits of the EU. The data are significantly different from a normal distribution of DON in samples of corn and corn products from different locations (p < 0.05) for Shapiro-Wilk and Kolmogorov-Smirnov values. However, a significant difference in DON levels was found between corn and corn-derived products (p ≤ 0.05). The lowest and highest exposures, and hazard quotient (HQ) values of 0.92 and 9.68 µg/kg bw/day, were documented in corn flour samples.


Assuntos
Contaminação de Alimentos/análise , Tricotecenos/análise , Zea mays/química , Cromatografia Líquida de Alta Pressão , Contaminação de Alimentos/estatística & dados numéricos , Índia , Paquistão , Medição de Risco
8.
Plant Sci ; 307: 110882, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33902850

RESUMO

Lodging is one of the causes of maize (Zea mays L.) production losses worldwide and, at least, the resistance to stalk lodging has been positively correlated with stalk strength. In order to elucidate the putative relationship between cell wall, stalk strength and lodging resistance, twelve maize inbreds varying in rind penetration strength and lodging resistance were characterized for cell wall composition and structure. Stepwise multiple regression indicates that H lignin subunits confer a greater rind penetration strength. Besides, the predictive model for lodging showed that a high ferulic acid content increases the resistance to lodging, whereas those of diferulates decrease it. These outcomes highlight that the strength and lodging susceptibility of maize stems may be conditioned by structural features of cell wall rather than by the net amount of cellulose, hemicelluloses and lignin. The results presented here provide biotechnological targets in breeding programs aimed at improving lodging in maize.


Assuntos
Parede Celular/química , Parede Celular/fisiologia , Caules de Planta/química , Caules de Planta/crescimento & desenvolvimento , Zea mays/química , Zea mays/crescimento & desenvolvimento , Zea mays/genética , Parede Celular/genética , Produtos Agrícolas/química , Produtos Agrícolas/genética , Produtos Agrícolas/crescimento & desenvolvimento , Resistência à Doença/genética , Resistência à Doença/fisiologia , Variação Genética , Genótipo , Fenótipo , Caules de Planta/genética
9.
Molecules ; 26(8)2021 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-33920373

RESUMO

The study focused on the influence of starch modified by octenyl succinic anhydride (OSA) on the rheological and thermal properties of gluten-free dough containing corn and potato starch with the addition of pectin and guar gum as structure-forming substances. The starch blend used in the original dough recipe was partially (5% to 15%) replaced with OSA starch. The rheological properties of dough samples were determined, and the properties of the resulting bread were analyzed. It was found that the dough samples behaved as weak gels, and the values of storage and loss moduli (G' and G″, respectively) significantly depended on angular frequency. Various shares of OSA starch in recipes modified dough in different ways, causing changes in its rheological characteristics. The introduction of OSA starch preparations resulted in changes in the bread volume and physical characteristics of the crumb. All the applied preparations caused an increase in bread porosity and the number of pores larger than 5 mm, and there was a parallel decrease in pore density. The presence of OSA starch preparations modified bread texture depending on the amount and type of the applied preparation. The introduction of OSA starches in gluten-free bread formulation caused a significant drop in the enthalpy of retrograded amylopectin decomposition, indicating a beneficial influence of such type of additive on staling retardation in gluten-free bread.


Assuntos
Pão/análise , Tecnologia de Alimentos/métodos , Galactanos/química , Mananas/química , Pectinas/química , Gomas Vegetais/química , Amido/análogos & derivados , Culinária/métodos , Dieta Livre de Glúten , Humanos , Porosidade , Reologia , Amido/química , Zea mays/química
10.
Nutrients ; 13(3)2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33807073

RESUMO

Macro and micronutrient deficiencies pose serious health challenges globally, with the largest impact in developing regions such as subSaharan Africa (SSA), Latin America and South Asia. Maize is a good source of calories but contains low concentrations of essential nutrients. Major limiting nutrients in maize-based diets are essential amino acids such as lysine and tryptophan, and micronutrients such as vitamin A, zinc (Zn) and iron (Fe). Responding to these challenges, separate maize biofortification programs have been designed worldwide, resulting in several cultivars with high levels of provitamin A, lysine, tryptophan, Zn and Fe being commercialized. This strategy of developing single-nutrient biofortified cultivars does not address the nutrient deficiency challenges in SSA in an integrated manner. Hence, development of maize with multinutritional attributes can be a sustainable and cost-effective strategy for addressing the problem of nutrient deficiencies in SSA. This review provides a synopsis of the health challenges associated with Zn, provitamin A and tryptophan deficiencies and link these to vulnerable societies; a synthesis of past and present intervention measures for addressing nutrient deficiencies in SSA; and a discussion on the possibility of developing maize with multinutritional quality attributes, but also with adaptation to stress conditions in SSA.


Assuntos
Biofortificação/métodos , Zea mays/química , África , Aminoácidos , Dieta , Alimentos Fortificados , Edição de Genes , Humanos , Ferro/metabolismo , Desnutrição/epidemiologia , Micronutrientes , Valor Nutritivo , Proteínas de Plantas , Plantas Geneticamente Modificadas , Provitaminas , Fatores de Risco , Vitamina A , Deficiência de Vitamina A , Zea mays/genética , Zinco/metabolismo
11.
Nutrients ; 13(4)2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33923768

RESUMO

Surveillance data have highlighted continued disparities in neural tube defects (NTDs) by race-ethnicity in the United States. Starting in 2016, the Food and Drug Administration (FDA) authorized voluntary folic acid fortification of corn masa flour to reduce the risk of neural tube defects (NTDs) among infants of Hispanic women of reproductive age. To assess the impact of voluntary corn masa fortification, cross-sectional data from the National Health and Nutrition Examination Survey (NHANES) 2011-2018 for Hispanic women of reproductive age with available red blood cell (RBC) folate concentrations were analyzed, with additional analyses conducted among Hispanic women whose sole source of folic acid intake was fortified foods (enriched cereal grain products (ECGP) only), excluding ready-to-eat cereals and supplements. RBC folate concentration (adjusted geometric mean) among Hispanic women of reproductive age did not differ between 2011-2016 and 2017-2018, though RBC folate concentration increased significantly among lesser acculturated Hispanic women consuming ECGP only. Concentrations of RBC folate for those born outside the U.S and residing in the U.S <15 years increased from 894 nmol/L (95% CI: 844-946) in 2011-2016 to 1018 nmol/L (95% CI: 982-1162; p < 0.001) in 2017-2018. Primarily Spanish-speaking Hispanic women of reproductive age who only consumed ECGP saw an increase from 941 nmol/L (95% CI: 895-990) in 2011-2016 to 1034 nmol/L (95% CI: 966-1107; p = 0.03) in 2017-2018. By subpopulation, we observed no significant changes in the proportion at risk of NTDs (<748 nmol/L) and no changes in the model-based estimated NTD rates following voluntary corn masa fortification. This analysis suggests that there is a remaining risk among Hispanics for folate sensitive NTDs, though continued monitoring of folate status in future NHANES data cycles will help inform the long-term efficacy of voluntary fortification of corn masa flour.


Assuntos
Farinha/análise , Ácido Fólico/administração & dosagem , Alimentos Fortificados/análise , Hispano-Americanos/estatística & dados numéricos , Zea mays/química , Aculturação , Adulto , Anencefalia/epidemiologia , Anencefalia/etnologia , Anencefalia/prevenção & controle , Estudos Transversais , Eritrócitos/química , Feminino , Ácido Fólico/sangue , Humanos , Recém-Nascido , Masculino , Fenômenos Fisiológicos da Nutrição Materna/efeitos dos fármacos , Fenômenos Fisiológicos da Nutrição Materna/etnologia , Inquéritos Nutricionais , Estado Nutricional , Estados Unidos/epidemiologia , Adulto Jovem
12.
Molecules ; 26(7)2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33916241

RESUMO

Anthocyanins are pigments with appealing hues that are currently being used as sources of natural colorants. The interaction of acylation on the stability of anthocyanin molecules has long been known. Maize is an abundant source of malonylglucoside and dimalonylglucoside anthocyanins. The enzyme Aat1 is an anthocyanin acyltransferase known to synthesize the majority of acylated anthocyanins in maize. In this paper, we characterize the substrate specificity and reaction kinetics of Aat1. It was found that Aat1 has anthocyanin 3-O-glucoside dimalonyltransferase activity and is only the second enzyme of this type characterized to this date. Our results indicate that Aat1 can utilize malonyl-CoA; succinyl-CoA and every anthocyanin 3-O-glucoside tested. Results of this study provide insight into the structure-function relations of dimalonyltransferases and give a unique insight into the activity of monocot anthocyanin acyltransferases.


Assuntos
Aciltransferases/química , Aciltransferases/metabolismo , Antocianinas/química , Antocianinas/metabolismo , Zea mays/química , Zea mays/enzimologia , Aciltransferases/genética , Aciltransferases/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Ativação Enzimática , Cinética , Espectrometria de Massas , Estrutura Molecular , Proteínas Recombinantes , Relação Estrutura-Atividade , Especificidade por Substrato , Zea mays/classificação , Zea mays/genética
13.
J Vis Exp ; (169)2021 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-33843934

RESUMO

The corn planthopper, Peregrinus maidis, is a pest of maize and a vector of several maize viruses. Previously published methods describe the triggering of RNA interference (RNAi) in P. maidis through microinjection of double-stranded RNAs (dsRNAs) into nymphs and adults. Despite the power of RNAi, phenotypes generated via this technique are transient and lack long-term Mendelian inheritance. Therefore, the P. maidis toolbox needs to be expanded to include functional genomic tools that would enable the production of stable mutant strains, opening the door for researchers to bring new control methods to bear on this economically important pest. However, unlike the dsRNAs used for RNAi, the components used in CRISPR/Cas9-based genome editing and germline transformation do not easily cross cell membranes. As a result, plasmid DNAs, RNAs, and/or proteins must be microinjected into embryos before the embryo cellularizes, making the timing of injection a critical factor for success. To that end, an agarose-based egg-lay method was developed to allow embryos to be harvested from P. maidis females at relatively short intervals. Herein are provided detailed protocols for collecting and microinjecting precellular P. maidis embryos with CRISPR components (Cas9 nuclease that has been complexed with guide RNAs), and results of Cas9-based gene knockout of a P. maidis eye-color gene, white, are presented. Although these protocols describe CRISPR/Cas9-genome editing in P. maidis, they can also be used for producing transgenic P. maidis via germline transformation by simply changing the composition of the injection solution.


Assuntos
Sistemas CRISPR-Cas/genética , Edição de Genes/métodos , Zea mays/química , Animais , Endonucleases/genética , Feminino
14.
Int J Mol Sci ; 22(5)2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33807972

RESUMO

Antimicrobial peptides (AMPs) are small molecules consisting of less than fifty residues of amino acids. Plant AMPs establish the first barrier of defense in the innate immune system in response to invading pathogens. The purpose of this study was to isolate new AMPs from the Zea mays L. inbred line B73 and investigate their antimicrobial activities and mechanisms against certain essential plant pathogenic bacteria. In silico, the Collection of Anti-Microbial Peptides (CAMPR3), a computational AMP prediction server, was used to screen a cDNA library for AMPs. A ZM-804 peptide, isolated from the Z. mays L. inbred line B73 cDNA library, was predicted as a new cationic AMP with high prediction values. ZM-804 was tested against eleven pathogens of Gram-negative and Gram-positive bacteria and exhibited high antimicrobial activities as determined by the minimal inhibitory concentrations (MICs) and the minimum bactericidal concentrations (MBCs). A confocal laser scanning microscope observation showed that the ZM-804 AMP targets bacterial cell membranes. SEM and TEM images revealed the disruption and damage of the cell membrane morphology of Clavibacter michiganensis subsp. michiganensis and Pseudomonas syringae pv. tomato (Pst) DC3000 caused by ZM-804. In planta, ZM-804 demonstrated antimicrobial activity and prevented the infection of tomato plants by Pst DC3000. Moreover, four virulent phytopathogenic bacteria were prevented from inducing hypersensitive response (HR) in tobacco leaves in response to low ZM-804 concentrations. ZM-804 exhibits low hemolytic activity against mouse red blood cells (RBCs) and is relatively safe for mammalian cells. In conclusion, the ZM-804 peptide has a strong antibacterial activity and provides an alternative tool for plant disease control. Additionally, the ZM-804 peptide is considered a promising candidate for human and animal drug development.


Assuntos
Antibacterianos , Proteínas Citotóxicas Formadoras de Poros , Pseudomonas syringae/crescimento & desenvolvimento , Zea mays/química , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Clavibacter/crescimento & desenvolvimento , Camundongos , Proteínas Citotóxicas Formadoras de Poros/química , Proteínas Citotóxicas Formadoras de Poros/genética , Proteínas Citotóxicas Formadoras de Poros/farmacologia , Zea mays/genética
15.
Artigo em Inglês | MEDLINE | ID: mdl-33720804

RESUMO

A novel adsorbent, called dithiocarboxyl cornstalk (DTCS), was developed, and the effects of various parameters on the adsorption performance for Cd(II) with DTCS were investigated in this work. The results suggested that DTCS presented the efficient removal capacity for Cd(II) when the pH values, adsorption temperature, and oscillation rate were 3.0 to 6.0, 313 K, and 150 rpm, respectively. The adsorption kinetic data were more agreed with pseudo-second-order kinetic model, and the isotherm data could be characterized by Freundlich model. The thermodynamic data indicated the adsorption process was endothermic and spontaneous. The FTIR and SEM confirmed the chemisorption between Cd(II) and DTCS. Furthermore, to eliminate the secondary pollution, the waste filtrate generated in the preparation of DTCS was employed to remove Cd(II) through flocculation experiments. The results showed that the waste filtrate is a potential flocculant for the treatment of wastewater containing Cd(II).


Assuntos
Cádmio/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Zea mays/química , Adsorção , Cádmio/química , Concentração de Íons de Hidrogênio , Cinética , Temperatura , Termodinâmica , Poluentes Químicos da Água/química
16.
Food Chem ; 353: 129468, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33730664

RESUMO

The impacts of two hydrothermal pretreatments, annealing (ANN) and heat moisture treatment (HMT), on oil-absorption by normal maize starch (NMS) during frying were investigated using low-field nuclear magnetic resonance (LF-NMR). The structural organizations of the fried samples were also evaluated using SEM, XRD, ATR-FTIR, and DSC, respectively. Both hydrothermal pretreatments significantly reduced the total oil content in the starch after frying, with the magnitude of the effect depending on the treatment conditions used. SEM showed that the pretreated fried starch granules preserved more of their original morphology. XRD, FTIR, and DSC showed that both pretreatments preserved more of the short-range double helices and long-range organizations within the orthorhombic crystalline structure for NMS during frying. The promoting effect of ANN/HMT on the interactions of starch molecules and the rearrangement of double helices were hypothesized to be responsible for the increased thermal stability of starch granules in the present work. As a result, fried starch pretreated by ANN/HMT were more organized and more compact than fried NMS, thus inhibiting oil absorption during frying.


Assuntos
Culinária/métodos , Óleo de Soja/química , Amido/química , Zea mays/química , Varredura Diferencial de Calorimetria , Temperatura Alta , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Varredura , Prótons , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
17.
Food Chem ; 353: 129449, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33714112

RESUMO

Effects of acid hydrolysis on amylose molecular structures and their relations to starch gelatinization properties were investigated. First-order kinetics models were applied to fit the evolution curve of starch chain-length and molecular size by acid hydrolysis treatment. Results showed that a single hydrolysis phase was involved in the degradation of waxy maize starch chains, while two distinct phases existed for the degradation of maize, high amylose maize and sago starch chains. The fast hydrolysis phase involved degradation of amylose chains with DP > ~300 and amylopectin long intra-cluster branches, while amylose chains with DP < ~300 was involved in the slow hydrolysis phase. Amylose molecules with DP ~ 300 were proposed to impact starch gelatinization properties by interaction with cut-off amylopectin double helices and formation of amylose crystallites/entanglements. This study could help food industry precisely control amylose molecular structures by acid hydrolysis treatment to develop starchy foods with desirable properties.


Assuntos
Gelatina/química , Amido/química , Zea mays/química , Amilopectina/química , Amilose/química , Cromatografia em Gel , Hidrólise , Modelos Químicos , Estrutura Molecular
18.
Isotopes Environ Health Stud ; 57(3): 271-280, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33730941

RESUMO

Understanding of nitrogen stable isotope variation in maize hybrids might help obtaining information on nitrogen absorption and distribution in different maize hybrids. In this study, we examined the nitrogen isotopic composition of different parts of maize hybrids under a laboratory culture experiment. The results showed that the δ15N values of different parts of the maize hybrid and its parents were ordered as follows: δ15Nstem>δ15Nleaf>δ15Nroot. The variation pattern of δ15N between the roots and leaves(Δδ15Nroot-leaf) of the maize hybrid was the same as that of δ15N between the roots and stems (Δδ15Nroot-stem). Therefore, the order of Δδ15Nroot-leaf as well as Δδ15Nroot-stem was as follows: Δδ15Nroot-leaf of the maize hybrid>Δδ15Nroot-leaf of the female parent (T4)>Δδ15Nroot-leaf of the male parent (803) and Δδ15Nroot-stem of the maize hybrid>Δδ15Nroot-stem of the female parent (T4)>Δδ15Nroot-stem of the male parent (803). This order is consistent with heterosis, indicating that differences in δ15N reflect the phenomenon of heterosis. The present study provides data in support of using the isotope technique to determine nitrogen distributions inside a plant and guide crossbreeding.


Assuntos
Isótopos de Nitrogênio/análise , Zea mays/química , Zea mays/genética , Quimera , China , Vigor Híbrido , Folhas de Planta/química , Folhas de Planta/genética , Raízes de Plantas/química , Raízes de Plantas/genética , Caules de Planta/química , Caules de Planta/genética
19.
Food Chem ; 352: 129353, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33662915

RESUMO

The research aimed to study the effect of stevia, xylitol, and corn syrup on the physical, physicochemical, and sensory properties of velvet tamarind chewy candy (VTCC). The content of sweeteners was optimized using stevia (5.5-6%), xylitol (5.5-6%), and corn syrup (7.5-8.5%) by mixture design (d-optimal) with 3 centerpoints and response surface methodology (RSM). The sweeteners in optimized VTCC consisted of velvet tamarind powder (40.5%), water (40%), stevia (6%), xylitol (6%), and corn syrup (7.5%) which provided the approximation error between prediction and observation values: of color (a* and b*), hardness, adhesiveness, gumminess, bioactive activities, and sensory properties within the range of 0.07-9.69%. The optimized VTCC using stevia and xylitol can reduce the sugar content by up to 60%. The sensory preference scores of VTCC from consumer acceptance were slightly like (6.1-6.9) which indicated that the VTCC with stevia and xylitol can provide satisfaction in all evaluated attributes and can be applied to this concept to create fruit chewy candy using stevia and xylitol.


Assuntos
Doces/análise , Diterpenos do Tipo Caurano/química , Glucosídeos/química , Edulcorantes/química , Tamarindus/química , Xilitol/química , Zea mays/química , Humanos
20.
Int J Mol Sci ; 22(5)2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33670954

RESUMO

Fusarium verticillioides causes multiple diseases of Zea mays (maize) including ear and seedling rots, contaminates seeds and seed products worldwide with toxic chemicals called fumonisins. The role of fumonisins in disease is unclear because, although they are not required for ear rot, they are required for seedling diseases. Disease symptoms may be due to the ability of fumonisins to inhibit ceramide synthase activity, the expected cause of lipids (fatty acids, oxylipins, and sphingolipids) alteration in infected plants. In this study, we explored the impact of fumonisins on fatty acid, oxylipin, and sphingolipid levels in planta and how these changes affect F. verticillioides growth in maize. The identity and levels of principal fatty acids, oxylipins, and over 50 sphingolipids were evaluated by chromatography followed by mass spectrometry in maize infected with an F. verticillioides fumonisin-producing wild-type strain and a fumonisin-deficient mutant, after different periods of growth. Plant hormones associated with defense responses, i.e., salicylic and jasmonic acid, were also evaluated. We suggest that fumonisins produced by F. verticillioides alter maize lipid metabolism, which help switch fungal growth from a relatively harmless endophyte to a destructive necrotroph.


Assuntos
Fumonisinas/toxicidade , Fusarium/química , Germinação , Metabolismo dos Lipídeos/efeitos dos fármacos , Micoses/metabolismo , Doenças das Plantas/microbiologia , Zea mays/efeitos dos fármacos , Ciclopentanos/análise , Ciclopentanos/metabolismo , Ácidos Graxos/análise , Ácidos Graxos/metabolismo , Fumonisinas/farmacologia , Micotoxinas/toxicidade , Oxilipinas/análise , Oxilipinas/metabolismo , Ácido Salicílico/análise , Ácido Salicílico/metabolismo , Esfingolipídeos/análise , Esfingolipídeos/metabolismo , Zea mays/química , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo
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