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1.
Compr Rev Food Sci Food Saf ; 20(1): 1075-1100, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33443809

RESUMO

In recent years, starch-based nanoparticles have attracted great interest due to their small size, good biocompatibility, and environmental friendliness, as well as their potential applications in foods, drug delivery carriers, and biodegradable edible films. Compared with nonstarch polysaccharides, starch can be enzymatically hydrolyzed into glucose in vivo, so it can be used as an enzyme-responsive carrier. The recent research progress of starch-based nanoparticles, including starch nanoparticles, starch nanospheres, starch micelles, starch vesicles, starch nanogels, and starch nanofibers, are reviewed in this paper. The main focus is on their responsiveness, digestibility, toxicity, interactions with other components, and applications. Starch-based nanoparticles are nontoxic and responsive to pH, temperature, light, and other stimuli. It can interact with proteins, antioxidants, and lipids through electrostatic interactions and hydrogen bonding interactions. Starch-based nanoparticles have a wide range of applications, including enhancing the mechanical properties of films and gels, stabilizing emulsions, as a fluorescent indicator, a catalyst, and a nanocarrier to control the release of active ingredients and drugs.

2.
J Hazard Mater ; 402: 123542, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-32745874

RESUMO

In this study, the nanocomposite film (SA-CS@CuO/ZnO) composed of sodium alginate (SA) and chitosan (CS) functionalized by copper oxide nanoparticles (CuONPs) and zinc oxide nanoparticles (ZnONPs) was fabricated, then its antibacterial mechanisms against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were systematically investigated. When the contents of CuONPs and ZnONPs reached 1.5 % (w/w) and 0.5 % (w/w), respectively, the SA-CS@CuO/ZnO exhibited great mechanical, barrier, and optical properties. Moreover, the incorporation of ZnONPs enhanced the photocatalytic ability of SA-CS@CuO/ZnO, producing a high level of reactive oxygen species under light irradiation. Further, antibacterial results showed that SA-CS@CuO/ZnO treatment inhibited the growth of E. coli and S. aureus higher than 60 % in the dark and exceeded 90 % under light irradiation. This was also manifested in the incompleteness of bacterial cell structure, accompanied by unstable cellular redox balance and DNA disruption. The functions of differentially expressed genes screened by transcriptome analysis were mainly involved in membrane transport, cell wall and membrane synthesis, cellular antioxidant defense system, cell membrane and DNA repair system. The changes in bacterial transcriptional regulation reflected the disturbance in the physiological activities and loss of cell integrity, leading to damage of bacterial cells or death.

3.
Int J Biol Macromol ; 2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-33278451

RESUMO

Recently, amylose-lipid complexes have attracted widespread attention because of their various applications. However, DBS complexed with fatty acids of different carbon chain length are rarely studied. This study aimed to probe the complexation of DBS with saturated fatty acids having different carbon chain lengths (C6-C18). The results revealed that DBS was able to form V-type complexes with all the fatty acids considered. Compared to DBS, the relative crystallinity of the complexes increased 2-3 times. DBS with lauric acid and myristic acid formed three types V-type complexes (type I, type IIa, and type IIb). The complexing index followed the order of hexanoic acid > octanoic acid > capric acid > lauric acid > myristic acid > palmitic acid > stearic acid. Furthermore, lauric acid and myristic acid formed complexes with DBS more easily compared with other fatty acids.

4.
Food Chem ; : 128638, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33248846

RESUMO

In this paper, the inhibitory effects of sorbitol on the collapse of gluten network and textural deterioration of fresh noodles during storage were investigated, based on the changes in macroscopic and microscopic characteristics of gluten protein. Appropriate addition (≤2%) of sorbitol increased dough viscoelasticity and extension energy. Sorbitol significantly inhibited the increase of cooking loss and adhesiveness of fresh noodles, and the decrease of hardness, springiness, LA-SRC value, and GMP weight during storage. SEM images showed that sorbitol retarded the deterioration of gluten network, with maintained continuous and ordered structure after 48 h. Sorbitol enhanced the hydrogen bond interactions in gluten system and promoted dynamic depolymerization and repolymerization of gluten protein molecules during processing and cooking, this may induce the texture stability. Sorbitol as a low-molecular polyol can inhibit the deterioration in gluten network and fresh noodle texture during storage, although showing no influence on the growth of microorganisms.

5.
Int J Biol Macromol ; 163: 2048-2059, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32961176

RESUMO

In this work, we aimed to investigate the effect of the combination of starch nanoparticles (SNPs) and Tween 80 (TW) on the stability of oil-in-water emulsions. The emulsions prepared under different SNPs/TW ratios and different oil fraction values were characterized by means of photography, optical microscopy, laser particle size analysis, rheological measurement, quartz crystal microbalance analysis, and confocal laser scanning microscopy. At an oil fraction value of 0.4, the emulsions with a 3: 1 ratio of SNPs (1.5%, w/v) to TW (0.5%, w/v) exhibited excellent storage stability over a long period of 30 d, which was significantly better than the 2% TW stabilized emulsion and the 2% SNPs stabilized emulsion. Compared with the SNPs stable emulsions, the presence of TW decreased the emulsion droplets size, which was beneficial to reduce the aggregation of droplets. Emulsions co-stabilized by SNPs and TW can maintain good performance under harsh conditions. The results of quartz crystal microbalance analysis and isothermal titration calorimetry revealed non-covalent interactions between SNPs and TW. The results showed that SNPs and TW co-existed at the oil-water interface and improved the performance of the emulsion.

6.
Carbohydr Polym ; 246: 116586, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32747246

RESUMO

Chitosan hydrogels fabricated by covalent crosslinking exhibit tough mechanical properties and chemical stability. In this paper, debranched starch (DBS) is oxidized to dialdehyde debranched starch (DADBS), which is used as a new type of a crosslinking agent to prepare hydrogels. Chitosan hydrogels with excellent properties are prepared by dynamic Schiff-base crosslinking between the aldehyde groups in DADBS and the amino groups in chitosan. Hence, chitosan hydrogels exhibit a rapid gelation ability, with a gelation time of less than 30 s, and their storage modulus increases with the gelation time. By adjusting the molar ratio of the amino group of chitosan to the aldehyde group of DADBS and the reaction temperature, the hydrogels exhibit tunable elasticity and mechanical properties. Notably, scanning electron microscopy revealed the presence of 100-200 nm microgels in the hydrogel network, which could exert a strengthening effect on the mechanical properties of the hydrogels. In addition, chitosan hydrogels exhibit a rapid self-healing ability and remarkable fluorescence properties; also, they can be 3D printed in different shapes. Overall, the DADBS cross-linked chitosan hydrogels demonstrate potential applications in food, medicine, agriculture, and materials.

7.
Int J Biol Macromol ; 163: 1557-1564, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32784021

RESUMO

The rapid fabrication of starch gels with excellent mechanical properties still presents a challenge. This study aimed to develop a simple alcohol soaking method to fabricate strong starch gels in a short time. The mechanical properties, crystallization behaviors, and structural characteristics of starch gels were investigated by rheological testing, texture profile analysis, differential scanning calorimetry (DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and low-field nuclear magnetic resonance (LF-NMR). The mechanical strength of the starch gel increased from 170.21 g to 666.16 g. The gelation time of starch gel decreased from 12 h (traditional retrogradation) to 2 h. DSC indicated that the enthalpy of starch gel increased from 0.88 J/g to 2.90 J/g. XRD analysis showed that the crystallinity of starch gel increased from 3.8% to 8.9% after alcohol soaking. Alcohol dehydrated the starch gels system, so that amylopectins were arranged to form more crystals. This new simple approach, alcohol soaking to form strong starch gels, can expand the applications of starch in food, agriculture, and textiles.

8.
Materials (Basel) ; 13(16)2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32823965

RESUMO

The 6061 aluminum alloy and 304 stainless steel were welded by hybrid cold metal transfer (CMT) welding with external axial magnetic field. The effects of magnetic intensity and frequency on joint microstructure and mechanical properties were studied. It was found that the magnetic field can promote the spreading of aluminum weld metal on the steel surface and thus increase the bonding area of Al/steel butt joint. The welding process stability improved, while the wetting behavior worsened with the introduction of alternating frequencies. The thickness of the intermetallic compound (IMC) layer at Al/steel interface was reduced to 3 µm with the coil current of 2 A. The application of the magnetic field promoted the aggregation of Si atoms at the interface and inhibited the formation of brittle (Al, Si)13Fe4 phase. The fracture paths were transformed from (Al, Si)13Fe4 layer to Al8Fe2Si layer with the application of the magnetic field. The maximum tensile strength reached 130.2 MPa, an increase of 61.6% in comparison to the normal CMT process.

9.
J Agric Food Chem ; 68(37): 10174-10183, 2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32816465

RESUMO

Nanoparticles (NPs) can form a protein corona (PC) with proteins in biological fluids. We examined whether starch nanoparticles (SNPs) form a PC and interact with digestive enzymes in simulated gastric and intestinal fluids. We investigated the adsorption of pepsin and trypsin on unmodified, carboxyl-, and amino-modified SNPs (SNPs, COOH-SNPs, and NH2-SNPs, respectively). Quartz crystal microbalance data showed that a tight and irreversible pepsin corona formed on the NH2-SNPs, pepsin had little or no binding to the SNPs and COOH-SNPs, and trypsin had weak binding to all three kinds of NPs. Dynamic light scattering data showed that pepsin significantly increased the size of the NH2-SNPs from 120 ± 2.6 to 203 ± 12.2 nm and decreased their surface potential from 23.2 ± 1.0 to 12.7 ± 0.2 mV. NH2-SNPs could induce the fluorescence quenching of pepsin and change its secondary structures without affecting its activity.

10.
Food Res Int ; 135: 109308, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32527475

RESUMO

The possibility of combining the health benefits of kafirin and polyphenols and improving the bioavailability of resveratrol using hollow kafirin nanoparticles via gallic acid crosslinking was investigated. The size, morphology, charge state, loading efficiency, physicochemical stability, and redispersity after lyophilization of hollow resveratrol-loaded kafirin nanoparticles formed via gallic acid crosslinking were characterized and compared with their solid counterparts and those without crosslinking. The nanoparticles formed were anionic spheres with an average diameter of <100 nm when loading amounts of resveratrol were less than 20%. The hollow nanoparticles were homogenous and still achieved stable colloidal dispersion after lyophilization. The hollow nanoparticles crosslinked with gallic acid displayed stability against pancreatin and delayed release in stimulated digestion. The results suggested that hollow kafirin nanoparticles could be a favorable colloidal delivery system for incorporating resveratrol.

11.
Int J Biol Macromol ; 161: 481-491, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32534085

RESUMO

Starch nanoparticles are promising candidates for the delivery of active compounds or drugs. The purpose of this study was to prepare nanoparticles from debranched starch using an ionic gelation method. Negatively charged carboxymethyl debranched starch (CMDBS) was obtained by modification of debranched starch (DBS). The zeta potential value of CMDBS with a degree of substitution of 0.81 was approximately -26 mV. The starch nanoparticles formed from 2 mg mL-1 CMDBS and cationized DBS (CDBS) had particle sizes of 50 to 100 nm, as determined by transmission electron spectroscopy, and most nanoparticles were spherical in shape. Measurements with a quartz crystal microbalance with dissipation monitoring confirmed a successful adsorption interaction between the negatively charged CMDBS and positively charged CDBS. Epigallocatechin gallate (EGCG) was successfully incorporated into the nanoparticles with the highest encapsulation efficiency of 84.4%, and the resulting nanoparticles showed controlled release of EGCG into simulated gastric and intestinal fluids.

13.
Food Chem ; 323: 126851, 2020 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-32334318

RESUMO

The development of hollow nanoparticles has attracted widespread interest due to their potential commercial applications. This work aimed to prepare a novel hollow starch nanoparticles (HSNPs) from debranched waxy corn starch (DBS) via an oil-in-water (O/W) emulsion templating method. The effects of different concentrations of DBS on the formation of HSNPs at 4 °C and 25 °C were investigated. The monodispersed HSNPs obtained with 0.5% concentrations of DBS at 25 °C had spherical shapes, ranging between 200 and 800 nm. HSNPs with relative crystallinities of 16.9%-29.7% exhibited V-type or B + V-type structures, which indicated that DBS at low concentrations (0.5%-2.0%) could recrystallize and concomitantly form starch-lipid complexes around emulsion droplets. This novel approach of preparing HSNPs is viable and simple. The developed HSNPs could have great potential for delivering drugs or active ingredients.

14.
Food Chem ; 318: 126495, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32146308

RESUMO

Wheat-based products are staple foods for over a third of the world's population. However, most wheat-based staple foods are provided with a high water content to maintain naturally chewable mouthfeel, which leads to a short shelf life and limits their distribution and marketing. Understanding the fundamental mechanisms and dynamics that drive the quality deterioration is therefore essential for obtaining alternative technologies for optimal quality and extended shelf life. Here, we provide the basis for the physicochemical, structural, and molecular changes occurring in various wheat products during storage, intending to elucidate the underlying deterioration causes. Generally, more desirable qualities are obtained for fresh wheat products, both in appearance and mouthfeel. During storage, changes in the physicochemical properties, structure, main constituents, and water status contribute to the quality deterioration. Based on these changes, deterioration mechanisms are summarized to provide both theoretical and practical references for the quality regulation of high-moisture wheat-based food.


Assuntos
Triticum/química , Água/análise , Análise de Alimentos , Armazenamento de Alimentos , Humanos , Paladar
15.
Food Chem ; 318: 126479, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32135423

RESUMO

In this study, we prepared waxy maize starch nanocrystals (SNCs) for the first time using dry-heated oxalic acid hydrolysis with or without ultrasonic treatment. The dry-heating treatment was subjected to oxalic acid hydrolysis to produce SNCs with a high yield of 89.6%. Dynamic light scattering showed that the size of the obtained SNCs was 46.58-197.15 nm, and the polydispersion index was 0.28-0.52. Atomic force microscopy investigation found that the SNCs had a major axis of about 211.5 nm and a height of about 9.4 nm. The thermogravimetric analysis revealed that the SNCs' thermal stability slightly improved compared with that of native starch. X-ray diffraction indicated that the produced SNCs preserved the A-type crystal form of native starch, with the relative crystallinities of 29.52%-42.44%. The newly fabricated SNCs have potential applications in agriculture, cosmetics, and advanced materials.


Assuntos
Nanopartículas/química , Amido/química , Zea mays/química , Difusão Dinâmica da Luz , Hidrólise , Microscopia de Força Atômica , Microscopia Eletrônica de Transmissão , Ácido Oxálico/química , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Ultrassom , Difração de Raios X
16.
Int J Biol Macromol ; 153: 341-348, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32142850

RESUMO

After gelatinization, starch is prone to retrograde during storage, and it is a notorious challenge to inhibit starch retrogradation in papermaking, textile, and construction fields. This work aimed to develop a new method for inhibiting the retrogradation of normal corn starch (CS) and waxy corn starch (WCS) by sodium borohydride (NaBH4). Differential scanning calorimetry analysis suggested that addition of 2.0% (at dry starch basis, w/w) NaBH4 can completely inhibit WCS retrogradation. X-ray diffraction results showed that, as the NaBH4 concentration increased, the crystallinity of CS and WCS gradually decreased. After seven days of storage at 4 °C, the relative crystallinity of CS and WCS with 2.0% NaBH4 decreased by 62.22% and 100%, respectively. Low field nuclear magnetic resonance analysis showed that the incorporation of NaBH4 remarkably affected the change of relaxation time(T2). The T2 changes in the gelatinized CS and WCS with 2.0% NaBH4 were much lower than gelatinized CS and WCS without NaBH4. The addition of NaBH4 led to a reduction in the hydrogen bonding of CS and WCS, which was confirmed by Fourier transform infrared spectroscopy (FTIR). It was concluded that the addition of 2.0% NaBH4 can significantly inhibit the retrogradation of CS and WCS.

17.
Int J Biol Macromol ; 150: 644-653, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32061844

RESUMO

Debranching modifications of waxy corn starch with pullulanase can generate short-chain amylose or debranched starch (DBS), which is easy to recrystallize. Herein, we firstly investigated the regulation of recrystallization behaviors of DBS by studying the interactions between DBS and emulsifiers, polyphenols, and fatty acids. Sodium dodecyl sulfate at the 3.0% level had strong interactions with DBS. When the concentration of epigallocatechin gallate was 15%, the enthalpy change (ΔH) of DBS was close to 0 J/g and the relative crystallinity of DBS was 0, clearly indicating the strong interactions between epigallocatechin gallate and DBS. When the concentration of caproic acid, caprylic acid, and capric acid increased from 0 to 20.0%, the ΔH of DBS decreased from 11.38 ± 0.01 to 3.90 ± 0.63, 1.39 ± 0.21, and 3.98 ± 0.83 J/g, respectively. The interactions between emulsifiers, polyphenols, and fatty acids and DBS could affect physiochemical properties of DBS in varying degrees.

18.
Food Chem ; 308: 125676, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31655476

RESUMO

In this study, the improving effects of green tea powder, soluble tea, and tea polyphenols on the mixing and tensile qualities of dough and texture of tea-enriched noodles, as well as the physico-chemical and structural properties of gluten proteins were progressively investigated. Dough strength and noodle texture were significantly increased by all the three tea products. Tea polyphenols in particular presented the most effective improvement with highest dough stability, resistance, and noodle chewiness. SEM indicated that tea products all induced a more developed gluten network, and polyphenol noodle showed the most continuous and ordered structure. FT-IR and fluorescence spectrum indicated that tea polyphenols promoted an enhancement in α-helix structure and the hydrophobic interactions. Tea polyphenols induced the SH/SS interchange during processing and cooking, and enhanced the water-solids interaction in noodles. AFM results showed that polyphenols induced the polymerization of gluten protein molecular chains, with increased chain height and width.


Assuntos
Polifenóis/química , Chá/química , Triticum/química , Fenômenos Químicos , Culinária , Glutens/química , Espectroscopia de Infravermelho com Transformada de Fourier
19.
Food Res Int ; 127: 108768, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31882092

RESUMO

The effects of two anionic polysaccharides (pectin and xanthan gum) on the in vitro lipid digestibility of fish oil-in-water emulsions stabilized by hydrolyzed rice glutelin (HRG) were determined. The emulsions were passed through a simulated gastrointestinal tract (GIT) consisting of mouth, stomach, and small intestine phases. The physicochemical properties of the colloidal particles in the gastrointestinal fluids (mean particle diameter, ξ-potential, and structural organization) were monitored throughout the GIT. In addition, the kinetics of lipid digestion was characterized in the small intestine phase. Interestingly, the addition of polysaccharide led to a marked increase in both the rate and extent of lipid digestion, with the effect depending on polysaccharide type. For instance, the initial rates of lipid digestion were 8.6 ±â€¯0.6, 13.3 ±â€¯0.4 and 16.1 ±â€¯0.6% free fatty acids (FFA) released min-1 for HRG emulsions containing no polysaccharides, pectin, and xanthan gum, respectively. Similarly, the calculated final extents of lipid digestion were 71.9 ±â€¯3.6, 97.7 ±â€¯3.2, and 100.0 ±â€¯3.8%, respectively. This was probably because the polysaccharides inhibited droplet flocculation, thereby increasing the surface area of lipids exposed to the digestive enzymes. Moreover, the polysaccharides may have interacted with other components involved in the lipid digestion process, such as enzymes, bile salts, and calcium ions. Our results may facilitate the design of plant-based functional foods and beverages that can control lipid digestion in the gastrointestinal tract.

20.
J Agric Food Chem ; 67(49): 13648-13657, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31747263

RESUMO

With the goal of improving the mechanical strength of chitosan hydrogels, gallic acid modified carboxymethyl chitosan/iron ion (GA-CMCS/FeIII) complex hydrogels were initially prepared via noncovalent interactions and metal coordination. 1H NMR, 13C NMR, and Fourier trantsform infrared spectra analysis confirmed the covalent reactions between CMCS and GA. The formation of GA-CMCS hydrogel occurred through electrostatic interactions, hydrogen bonds, and hydrophobic interactions. GA-CMCS/FeIII hydrogel (380 kPa) exhibited higher compressive strength than GA-CMCS hydrogel (315 kPa). In addition, GA-CMCS/FeIII aerogel displayed satisfactory mechanical strength (1.59 MPa) and high-efficiency adsorption capacities up to 97.15 mg/g for Pb2+, 99.75 mg/g for Cd2+, and 98.50 mg/g for Cu2+, respectively. In addition, both of the GA-CMCS and GA-CMCS/FeIII aerogel adsorbents exhibited satisfactory recyclability. The design of GA-CMCS and GA-CMCS/FeIII hydrogels and aerogels offers a new opportunity for the construction of physically multi-cross-linked systems with excellent mechanical properties.


Assuntos
Quitosana/análogos & derivados , Metais/química , Adsorção , Quitosana/química , Compostos Férricos/química , Ácido Gálico/química , Hidrogéis/química , Concentração de Íons de Hidrogênio
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