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1.
Food Chem ; 372: 131240, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34619520

RESUMO

Non-thermal plasma has increasingly been used for surface modification of various materials as a novel green technology. In this study, we prepared potato starch nanocrystals (SNCs) assisted by dielectric barrier discharge plasma technology and investigated its multiscale structure, physicochemical properties and rheology. Plasma treatment did not change the morphology and crystalline pattern of SNCs but reduced the crystallinity. The amylose content, swelling power, gelatinization temperature, and apparent viscosity of SNCs decreased after the plasma process by depolymerizing the amylopectin branch chains and degrading SNCs molecules. Besides, plasma increased the rapidly digestible starch and resistant starch content. Changes in rheological properties of plasma treated SNCs suggested that the plasma process increased the flowing capacity. The effective structural and functional changes of plasma treated SNCs confirm that plasma technology has great potential for modification of SNCs.


Assuntos
Nanopartículas , Solanum tuberosum , Amilopectina , Amilose , Reologia , Amido , Viscosidade
2.
Food Chem ; 371: 131060, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34555707

RESUMO

Potato starch spherulites (PSS) with different molecular weights were obtained by controlled enzymatic hydrolysis of potato amylose starch, followed by super-heated quenching treatment. The impact of enzymatic hydrolysis on mean particle diameter and molecular weight was observed, ranging from 355 to 57 nm. Structural and physicochemical characteristics of produced spherulites were determined using scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, differential scanning calorimetry and rheological measurements. Rheological analysis indicated that PSS sample was viscoelastic with shear-thinning behavior. PSS was found to exhibit weak B-type crystallinity, similarly to that in native starch. PSS25% had a higher thermal stability with 128.5 °C melting temperature. Microstructure confirmed there were small spherulites (1-3 µm) formed with hydrolyzed amylose starch, and starch with 15% enzymatic-hydrolysis degree was more beneficial to develop spherulite. These results may be useful in development of starch-based functional ingredients applied in plant-based foods as fat replacers, structure formers, or delivery systems.


Assuntos
Amilose , Solanum tuberosum , Peso Molecular , Amido , Difração de Raios X
3.
Food Chem ; 371: 131119, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34560335

RESUMO

Five rice cultivars were applied for investigating effect of milling degree on rice physicochemical properties. The first layer had the lowest peak viscosity, followed by the second and third layers, indicating the effect of non-starchy components on starch gelatinization behaviors. Consistently, more content of non-starch components in the first layer led to an enhanced gelatinization temperature. Rheological study demonstrated the G' and G" were successively increased as the layer moved inward, indicating a stronger gel network due to the increased amylose content and crystallinity in the corresponding layer. This is the first study to reveal the second layer has the highest digestibility, suggesting both non-starch components and starch structure control starch digestion. Furthermore, analysis of volatile compounds found alcohols and ketones concentrated in the first layer, whilst compounds including (E,E)-2,4-decadienal, 3-octanone and 3-nonen-2-one only existed in the second layer, serving as an indicator for managing the rice quality during milling.


Assuntos
Oryza , Amilose , Grão Comestível , Amido , Viscosidade
4.
Food Chem ; 367: 130580, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34371274

RESUMO

In order to determine the mechanisms underlying resistant starch formation, three treatments were used to prepare resistant starch from purple sweet potato. The resistant starch yield, amylose content, chain length distribution, thermal properties, and crystal structure were determined, and the results were compared with those of unmodified starch. Autoclaving, pullulanase, and pullulanase-autoclaving treatments significantly increased the resistant starch yield, amylose content, shorter amylopectin branch content, and gelatinisation temperatures of native purple sweet potato starch. Resistant starch prepared via pullulanase-autoclaving combination treatment exhibited the highest gelatinisation enthalpy value and the greatest degree of overall thermal stability. X-ray diffraction patterns and Fourier-transform infrared spectra analysis demonstrated that all three treatments transformed the starch crystalline structure from C-type to B-type, and no new groups were generated during the modification process; all the processes were only physical modifications.


Assuntos
Ipomoea batatas , Amilopectina , Amilose , Amido Resistente , Amido , Difração de Raios X
5.
Food Chem ; 369: 131000, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34492613

RESUMO

Starch retrogradation involves nucleation and crystal growth steps, while their relative contribution to the overall retrogradation kinetics and relations with starch fine molecular structures have not been elucidated. In this study, a consecutive reaction kinetics model (CRK) was developed to fit long-term retrogradation kinetics curves for 10 rice starches with distinct molecular structures. Starch chain-length distributions (CLDs) and melting enthalpy kinetics curves for these starches were obtained from our published data. It was shown that these melting enthalpy kinetics curves can be satisfactorily deconvoluted by the CRK model into a combination of nucleation and crystal growth curves. Correlation analysis between CRK model-fitted parameters with starch CLDs showed that starch retrogradation nucleation and crystal growth steps were controlled by distinct starch fine molecular structures. These results have practical applications, as it enables a separate regulation of nucleation and crystal growth steps during retrogradation process of starch-based foods for desirable nutritional properties.


Assuntos
Amilopectina , Oryza , Amilose , Cinética , Estrutura Molecular , Amido
6.
Food Chem ; 369: 130824, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34438341

RESUMO

Cyperus esculentus starch was treated by pullulanase debranching and nanoprecipitation to prepare resistant starch nanoparticles. Amylose contents, rheological properties of debranched starch and the size, crystalline structure, resistant starch contents of the prepared starch nanoparticles were investigated. The results of amylose contents showed that enzymatic hydrolysis 4 h was the most appropriate enzymatic hydrolysis time. Dynamic light scattering analysis and scanning electron microscopy observations showed that when the starch solution was added to the ethanol, the larger the amount of ethanol, the more conducive to the formation of small size starch nanoparticles. When volume ratio of starch solution/ethanol was 1/5, the particle size was 271.1 nm, the content of resistant starch was higher (15.28%). X-ray diffraction results indicated that resistant starch nanoparticles had V-type crystalline structure. Pullulanase debranching and nanoprecipitation can be utilized to prepare smaller size of Cyperus esculentus resistant starch with higher efficiency.


Assuntos
Nanopartículas , Amido Resistente , Amilose , Tamanho da Partícula , Amido , Difração de Raios X
7.
Food Chem ; 368: 130806, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34399184

RESUMO

The objective of this study was to compare the in vitro digestibility of different buckwheat and wheat starch cultivars and establish the relationship between digestibility and structure of buckwheat starch. Structure of starches were analyzed with size exclusion chromatography and fluorophore-assisted capillary electrophoresis. Results showed that the amylose content of Tartary buckwheat starch (TBS) and common buckwheat starch (CBS) was 3-4% lower than that of wheat starch. However, no significant difference in the digestibility was found between them. The fast digestion rate coefficient of TBS was negatively correlated with the amount of long amylopectin chains (24 < DP ≤ 36), and the total digested starch percentage of CBS was negatively correlated with the amount of medium-long amylopectin chains (13 < DP ≤ 24). This suggests that the digestibility of fully gelatinized starch had no association with the botanical sources but may be more influenced by starch structure.


Assuntos
Fagopyrum , Amido , Amilopectina , Amilose , Estrutura Molecular , Triticum
8.
Food Chem ; 368: 130796, 2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34418691

RESUMO

In this study, we report important relationships between kernel starch and kernel dehydration rate for eight maize inbred lines with different dehydration characteristics. High-throughput RNA sequencing data of starch biosynthesis-related genes showed that kernel moisture content and dehydration rate were both associated with differential expression of most starch biosynthetic genes. Especially, kernel moisture content was positively correlated with the increased expression of SBEI and SBEIIb, thereby potentially inducing biosynthesis of amylose with low molecular weight and amylopectin with low content of amylopectin chains with degree of polymerization (DP) 6-12 in inbred lines with fast kernel dehydration rate. We found a negative correlation between short amylopectin chains (DP 6-12) and the starch retrogradation rate. Hence, a low amount of amylopectin chains with DP 6-12 in the inbred lines with fast kernel dehydration rate was a plausible reason for their high short- and long-term retrogradation.


Assuntos
Desidratação , Zea mays , Amilopectina , Amilose , Amido , Zea mays/genética
9.
Molecules ; 26(20)2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34684702

RESUMO

Procyanidins are contained in various foods, and their effects on starch hydrolysis have been reported. In Japan, black soybeans, which contain a trimeric procyanidin, procyanidin C1 (proC1), are cooked with rice and used to prepare dumplings. In this study, the effects of proC1 on the pancreatin-induced formation of reducing sugars and starch hydrolysis were studied using potato starch and corn starch. ProC1 inhibited both reactions; the inhibition was greater in potato starch than corn starch when added to heated potato starch and corn starch. When heated with proC1, its inhibitory effects decreased, especially in potato starch, suggesting the important role of proC1 itself for the inhibition of potato starch hydrolysis. ProC1 also inhibited the hydrolysis when added to heated, longer amylose (average molecular weight: 31,200), and the inhibition decreased when heated with the amylose. On the other hand, proC1 could not inhibit the hydrolysis when added to heated, shorter amylose (average molecular weight: 4500), but could when heated with the amylose, suggesting the important role of the degradation products of proC1 for the inhibition. We discuss the mechanism of the proC1-dependent inhibition of amylose hydrolysis, taking the molecular weight into account.


Assuntos
Flavonoides/metabolismo , Pancreatina/metabolismo , Amido/química , Amilose/química , Biflavonoides , Catequina , Culinária , Flavonoides/farmacologia , Flavonoides/fisiologia , Hidrólise/efeitos dos fármacos , Japão , Peso Molecular , Oryza/metabolismo , Pancreatina/química , Proantocianidinas , Solanum tuberosum/metabolismo , Amido/metabolismo , Zea mays/metabolismo
10.
BMC Plant Biol ; 21(1): 479, 2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34674662

RESUMO

Starch branching enzymes (SBEs) are key determinants of the structure and amount of the starch in plant organs, and as such, they have the capacity to influence plant growth, developmental, and fitness processes, and in addition, the industrial end-use of starch. However, little is known about the role of SBEs in determining starch structure-function relations in economically important horticultural crops such as fruit and leafy greens, many of which accumulate starch transiently. Further, a full understanding of the biological function of these types of starches is lacking. Because of this gap in knowledge, this minireview aims to provide an overview of SBEs in horticultural crops, to investigate the potential role of starch in determining postharvest quality. A systematic examination of SBE sequences in 43 diverse horticultural species, identified SBE1, 2 and 3 isoforms in all species examined except apple, olive, and Brassicaceae, which lacked SBE1, but had a duplicated SBE2. Among our findings after a comprehensive and critical review of published data, was that as apple, banana, and tomato fruits ripens, the ratio of the highly digestible amylopectin component of starch increases relative to the more digestion-resistant amylose fraction, with parallel increases in SBE2 transcription, fruit sugar content, and decreases in starch. It is tempting to speculate that during the ripening of these fruit when starch degradation occurs, there are rearrangements made to the structure of starch possibly via branching enzymes to increase starch digestibility to sugars. We propose that based on the known action of SBEs, and these observations, SBEs may affect produce quality, and shelf-life directly through starch accumulation, and indirectly, by altering sugar availability. Further studies where SBE activity is fine-tuned in these crops, can enrich our understanding of the role of starch across species and may improve horticulture postharvest quality.


Assuntos
Enzima Ramificadora de 1,4-alfa-Glucana/genética , Produtos Agrícolas/enzimologia , Isoenzimas , Amido/metabolismo , Enzima Ramificadora de 1,4-alfa-Glucana/metabolismo , Motivos de Aminoácidos , Amilopectina/metabolismo , Amilose/metabolismo , Produtos Agrícolas/genética , Produtos Agrícolas/normas , Grão Comestível , Armazenamento de Alimentos , Frutas , Horticultura , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Tubérculos , Açúcares/metabolismo , Verduras
11.
Nutrients ; 13(10)2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34684471

RESUMO

Obesity is due in part to increased consumption of a Western diet that is low in dietary fiber. Conversely, an increase in fiber supplementation to a diet can have various beneficial effects on metabolic homeostasis including weight loss and reduced adiposity. Fibers are extremely diverse in source and composition, such as high-amylose maize, ß-glucan, wheat fiber, pectin, inulin-type fructans, and soluble corn fiber. Despite the heterogeneity of dietary fiber, most have been shown to play a role in alleviating obesity-related health issues, mainly by targeting and utilizing the properties of the gut microbiome. Reductions in body weight, adiposity, food intake, and markers of inflammation have all been reported with the consumption of various fibers, making them a promising treatment option for the obesity epidemic. This review will highlight the current findings on different plant-based fibers as a therapeutic dietary supplement to improve energy homeostasis via mechanisms of gut microbiota.


Assuntos
Fibras na Dieta/administração & dosagem , Metabolismo Energético/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Homeostase , Extratos Vegetais/administração & dosagem , Amilose/administração & dosagem , Amilose/química , Animais , Fibras na Dieta/uso terapêutico , Glucanos , Avaliação do Impacto na Saúde , Humanos , Inulina , Pectinas , Extratos Vegetais/uso terapêutico , Zea mays/química
12.
Biomacromolecules ; 22(11): 4730-4737, 2021 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-34669391

RESUMO

Granule-bound starch synthase (GBSS) plays a major role, that of chain elongation, in the biosynthesis of amylose, a starch component with mostly (1 → 4)-α connected long chains of glucose with a few (1 → 6)-α branch points. Chain-length distributions (CLDs) of amylose affect functional properties, which can be controlled by changing appropriate residues on granule-bound starch synthase (GBSS). Knowing the binding of GBSS and amylose at a molecular level can help better determine the key amino acids on GBSS that affect CLDs of amylose for subsequent use in molecular engineering. Atomistic molecular dynamics simulations with explicit solvent and docking approaches were used in this study to build a model of the binding between rice GBSS and amylose. Amylose fragments containing 3-12 linearly linked glucose units were built to represent the starch fragments. The stability of the complexes, interactions between GBSS and sugars, and difference in structure/conformation of bound and free starch fragments were analyzed. The study found that starch/amylose fragments with 5 or 6 glucose units were suitable for modeling starch binding to GBSS. The removal of an interdomain disulfide on GBSS was found to affect both GBSS and starch stability. Key residues that could affect the binding ability were also indicated. This model can help rationalize the design of mutants and suggest ways to make single-point mutations, which could be used to develop plants producing starches with improved functional properties.


Assuntos
Oryza , Sintase do Amido , Amilose , Amido , Sintase do Amido/genética
13.
Se Pu ; 39(11): 1247-1254, 2021 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-34677020

RESUMO

Starch occurs naturally in the form of semicrystalline granules, and is composed of two types of carbohydrate molecules, amylose (AM) and amylopectin (AP). Starch granules and starch molecules have sizes in the range of 1-100 µm and 20-250 nm, respectively; these size ranges are among the key factors affecting the functional properties of starch. Asymmetrical flow field-flow fractionation (AF4) is a size-based separation technique. The major difference between AF4 and dynamic light scattering or microscopy techniques is that AF4 enables the separation of particles based on their size; consequently, the elution profile can be converted to the size distribution of the samples. In the last two decades, AF4 systems, when coupled online with multiangle light scattering (MALS) and differential refractive index (dRI) detectors (AF4-MALS-dRI), have demonstrated to be applicable for the size characterization of starch at the molecular level. Unlike size exclusion chromatography (SEC), AF4 systems use an open channel that does not require a stationary phase or packing materials. Thus, the shear scission of AP molecules during AF4 separation is minimized. The size detection range of a commercial AF4 system ranges from 1 nm to 10 µm, which is smaller than the size range of starch granules. In this study, a home-made AF4 system was developed, and its capability for the size characterization of starch granules extracted from sweet potato, lotus seed, and rice was investigated. The performance of the developed AF4 system was evaluated by running a mixture of polystyrene (PS) with diameter of 2, 6, 12, and 20 µm, respectively. Baseline separation of four PS samples was achieved, and the resolution for 6 µm PS and 12 µm PS was 1.40. The detection limit of the developed AF4 system was higher than that of commercial AF4 systems. Thus, the developed AF4 system is promising for the separation and characterization of starch granules. The effect of the composition of the carrier liquid on the AF4 separation of starch granules was also studied. Moreover, the accuracy of AF4 in terms of size characterization of the starch granules was evaluated by optical microscopy (OM). The results revealed that the type of dispersant and viscosity of the carrier liquid affect the accuracy of size characterization of the starch granules. The size distribution of rice starch granules obtained using a carrier liquid containing 0.01% (w/v) sodium dodecyl sulfate (used as a dispersant), 0.02% (w/v) NaN3 (used as a bactericide), and 0.001% (w/v) hydroxypropylmethylcellulose (used to adjust the viscosity of the carrier liquid) was in agreement with that obtained from OM. Furthermore, a commercial AF4 system coupled with MALS and dRI detectors was employed for the separation and characterization of starch molecules. A molecularly dispersed solution is necessary for the reliable molecular characterization of starch. The effect of the starch dissolution temperature on the AF4 characterization of starch was also investigated. The optimal dissolution temperature for lotus seed and rice starch granules was 75 ℃, while that for sweet potato starch granules was 78 ℃; this difference is mainly attributed to the different botanical origins of the granules. The results showed that the ratio of the radius of gyration (Rg) to the hydrodynamic radius (Rh) of rice starch and sweet potato starch is in the range of 0.9-1.1 over the molar mass range of 10 6-108 g/mol. For rice starch, the Rg/Rh ratio is between 1.2 and 1.4. Rice starch has the highest apparent density among the three starches, indicating that rice starch molecules have a dense structure. The results demonstrated that the AF4 system developed in this study is rapid and accurate for the size characterization of starch granules. The developed AF4 system, when combined with commercial AF4 systems coupled online with MALS and dRI detectors, can provide technical support to study the relationship between the size from the nanoscale to the microscale and functional properties of starch.


Assuntos
Fracionamento por Campo e Fluxo , Amilose , Peso Molecular , Refratometria , Amido
14.
J Genet ; 1002021.
Artigo em Inglês | MEDLINE | ID: mdl-34553697

RESUMO

The Waxy locus of rice is a highly polymorphic region embedded with microsatellite repeats in the 5'UTR leader intron 1 region, 23-bp duplication (wx motif) in exon 2, SNPs in exons 4, 6 and 10, p-Sine-r2 element in intron 1 and TnR-1 element in inton 13. Of the 80 polymorphic sites detected on the Wx gene, 24 are located in p-Sine-r2 and TnR-1 elements, revealing a higher substitution rate of bases in these two regions. All the cultivars with chalky endosperm had the 5'-AGTTATA-3' haplotype in intron 1 and 'A' to 'G' substitution at ?497 in exon 4. The AAC of starch from grains of all the accessions showed strong correlation (r=0.967) with GBSS-I activity in the grains. Based on the polymorphic sites of the Waxy locus and the GBSS-I activities, six allelic variants were defined which included wx, Wxop, Wxb, Wxin, Wxa2 and Wxa1, respectively, corresponded to glutinous, very low, low, intermediate, highII and highI amylose classes. Phylogenetic tree developed from alignment matrix of nucleotide sequences of the Waxy locus identified wx, Wxb and Wxin alleles with japonica lineage of Oryza sativa and the Wxop, Wxa2 and Wxa1 with indica lineage.


Assuntos
Alelos , Amilose/metabolismo , Domesticação , Oryza/genética , Amido/metabolismo , Sequência de Bases , Regulação da Expressão Gênica de Plantas , Loci Gênicos , Repetições de Microssatélites/genética , Modelos Moleculares , Motivos de Nucleotídeos/genética , Oryza/enzimologia , Filogenia , Polimorfismo Genético , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sementes/anatomia & histologia , Sementes/genética , Sintase do Amido/química , Sintase do Amido/genética , Sintase do Amido/metabolismo
15.
J Agric Food Chem ; 69(39): 11665-11675, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34469152

RESUMO

The use of combinations of aroma compounds is common in many food and cosmetic applications. To investigate the binding behavior between high-amylose maize starch and binary aroma combinations of decanal and thymol, starch-aroma inclusion complexes (ICs) were prepared by a one-step or two-step method with different concentrations and orders of addition. The thymol molecule induced the starch chain to form a larger helical cavity and was more likely to form hydrogen bonds with solvents. The encapsulation efficiency and loading efficiency of starch-thymol ICs were always higher than those of starch-decanal ICs, independent of the aroma concentration and addition order in binary aroma ICs. However, starch-decanal ICs prepared in the presence of thymol encapsulated more decanal than in the absence of thymol. The V6I-type crystals formed by starch-decanal ICs and the V6III-type crystals formed by starch-thymol ICs were both present in binary aroma ICs, resulting in a less-ordered structure and lower thermal transition temperatures. In summary, the complexation between binary aroma compounds and starch exhibited both cooperative and competitive binding behaviors. The synergistic effects between decanal and thymol provide guidance in enhancing the aroma encapsulation in starch carriers.


Assuntos
Amilose , Amido , Aldeídos , Odorantes/análise , Timol
16.
J Food Sci ; 86(9): 3975-3986, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34392534

RESUMO

Dry beans(Phaseolus vulgaris) are rich in complex carbohydrates including resistant starch (RS). RS, the starch fraction that escapes digestion, typically ranges from 35% in raw beans to 4% in cooked beans. A low RS bean genotype, Cebo Cela, was identified with 96% less RS (1.5% RS) than normal raw beans. The goal of this research was to elucidate the factors responsible for this low RS phenotype. The low RS phenotype was evaluated in whole bean flour and starch in Cebo Cela (yellow), Canario (yellow), Alpena (navy) and Samurai (otebo). α-Amylase activation was found to be a major contributor of the low RS content phenotype of the whole bean flour for Cebo Cela (-21.9% inhibition). Total starch (43.6%-40.2%), amylose (31.0%-31.5%), molecular weight and chain length distributions of amylose and amylopectin did not contribute to the low RS phenotype. Yellow bean starches were digested nearly 1.5 times (95%-94%) faster than starch granules from otebo and navy beans (65%-73%) due to lower proportions of amylopectin chains. PRACTICAL APPLICATION: This study is of value to the food industry because the yellow bean, Cebo Cela, is easily hydrolyzed by α-amylase and also has α-amylase promotion properties. Therefore, Cebo Cela can be used as an alternate starch source for ethanol fermentation and for the production of maltodextrins and fructose/glucose syrups which are used as food thickeners and sweeteners.


Assuntos
Análise de Alimentos , Phaseolus , Amido Resistente , Amilose/análise , Phaseolus/química , Fenótipo , Amido Resistente/análise
17.
Int J Mol Sci ; 22(14)2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34298901

RESUMO

The aim of the study was to determine how the molecular structure of porcine fat-in-water type emulsions stabilised with potato starch affected their rheomechanical properties. Dynamic mechanical analysis (DMA) and instrumental analysis of the texture were the method used in experiments. Starch gels with concentrations corresponding to the water starch concentration of the examined emulsions were used as control systems. The analysis of the starch and starch-fat systems showed that the values characterising their rheomechanical and textural properties reflected the spatial reaction of the amylose matrix to dynamic mechanical interactions. Changes in their values resulted from conformational changes in the structure of segments and nodes of the lattice, conditioned by the concentration of starch and the presence of fat. As a result of these changes, starch-fat emulsions are distinguished by greater densities of network segments and nearly two times greater functionalities of nodes than starch gels. The instrumental analysis of the texture showed that the values of the texture parameters in the starch gels were greater than in the starch-fat emulsions. The high values of the correlation coefficients (R~0.9) between the texture determinants and the rheological parameters proved that there was a strong correlation between the textural properties of the tested systems and their rheomechanical properties.


Assuntos
Emulsões/química , Gorduras/química , Solanum tuberosum/química , Amido/química , Água/química , Amilose/química , Animais , Géis/química , Estrutura Molecular , Reologia/métodos , Suínos
18.
Molecules ; 26(12)2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34198695

RESUMO

Unripe banana fruit of Musa acuminata (Musa AAA; Hom Khieo) and Musa sapientum L. (Musa ABB; Namwa) growing in Chiang Rai (Thailand) were used for extraction. The yield of the starches was 16.88% for Hom Khieo (HK) and 22.73% for Namwa (NW) based on unripe peeled banana fruit. The amylose contents of HK and NW were 24.99% and 26.23%, respectively. The morphology of starch granules was oval shape with elongated forms for large granules and round shape for small granules. The HK and NW showed B-type crystalline structure and the crystallinities were 23.54% and 26.83%, respectively. The peak temperature of gelatinization was around 77 °C and the enthalpy change (ΔH) was 3.05 and 7.76 J/g, respectively. The HK and NW banana starches showed 1.27 ± 0.12 g/g and 1.53 ± 0.12 g/g water absorption capacity, and 1.22 ± 0.11 g/g and 1.16 ± 0.12 g/g oil absorption capacity, respectively. The swelling power of the banana starches was 17.23 ± 0.94 g/g and 15.90 ± 0.15 g/g, respectively, and the percentage of solubility in water showed 26.43 ± 2.50 g/g and 20.54 ± 0.94 g/g, respectively. The banana starches showed very poor flow character. The HK and NW starches have the potential to be used in powder base preparations with no effect on the sensory texture of the product at 15% w/w maximum.


Assuntos
Amilose/química , Cosméticos/química , Musa/química , Amido/química , Temperatura , Termodinâmica , Difração de Raios X/métodos , Frutas , Solubilidade , Água
19.
J Chromatogr A ; 1653: 462406, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34320436

RESUMO

A simple and green high-performance liquid chromatography method for the separation of paroxetine from its enantiomeric and diastereomeric impurities has been developed. The simultaneous chromatographic resolution was carried out on the amylose-based Chiralpak IA-3 chiral stationary phase using the mixture ethanol-water-diethylamine 80:20:0.1 (v/v/v) as a mobile phase. The effects of substitution of ethanol with methanol or acetonitrile and changes in column temperature on selectivity have been carefully investigated. The optimized single-run HPLC protocol allows the baseline separation of the enantiomers of paroxetine without suffering from interference from five other chiral and achiral impurities reported in the monograph of the European Pharmacopoeia.


Assuntos
Amilose , Cromatografia Líquida de Alta Pressão , Química Verde , Paroxetina , Amilose/química , Química Verde/métodos , Metanol/química , Paroxetina/química , Paroxetina/isolamento & purificação , Estereoisomerismo
20.
PLoS One ; 16(7): e0254182, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34264963

RESUMO

Many studies have been carried out on N sources effect on fragrant rice; however, their impact on rice grain quality is largely unclear. In this study, we evaluated the effects of different types of N sources on rice growth, yield, 2-acetyl-1-pyrroline (2AP), amylose and cooked rice elongation. Two indica rice cultivars, Basmati 385 (B385), Xiangyaxiangzhan (XYXZ) and two japonica cultivars, Yunjingyou (YJY), Daohuaxiang (DHX) were grown in experimental pots with six replications under four N sources: Potassium nitrate (KNO3), ammonium bicarbonate (NH4HCO3), urea (H2NCONH2) and sodium nitrate (NaNO3) in 2019 and 2020 early seasons. Our results showed that N dynamics regulated the number of panicles, 1000-grain weight, grain yield, 2-acetyl-1-pyrroline, amylose and cooked rice elongation across all the four treatments. The NH4HCO3 treatment significantly increased the number of panicles and grain yield across the four rice varieties compared with KNO3, H2NCONH2 and NaNO3 N sources in both 2019 and 2020 early season, The KNO3 treatment significantly showed higher 1000-grain weight in B-385, YJY, XYXZ and DHX compared to other N sources. Compared with other N sources treatment, the NH4HCO3 treatments significantly increased the 2AP contents in heading stage leaves, matured leaves and grains of B-385, YJY, XYXZ and DHX respectively. Cooked rice elongation percentage also showed significant difference in all treatments studied with KNO3 recorded the highest across the four varieties. Analysis of major enzymes and compounds such as P5C, P5CS, PDH, Pyrroline, proline and Methylglyoxal showed remarkable differences in each cultivar at heading and maturity stages with higher activity in NH4HCO3 and H2NCONH2 treatments. Similarly, in all treatments, we also observed significant increase in amylose content percentage, with NH4HCO3 having greater percentage of amylose.


Assuntos
Amilose , Oryza , Culinária , Regulação da Expressão Gênica de Plantas , Nitrogênio
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