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1.
J Agric Food Chem ; 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39116173

RESUMEN

The formation pathway and mechanism of various pyrazines were investigated during the thermal treatment of the alanine-xylose Amadori compound (Ala-ARP) and exogenous alanine (Ala). 15N-labeled Ala was used to coheated with Ala-ARP to clarify the nitrogen sources and the respective contributions of exogenous Ala and the regenerated Ala released from Ala-ARP to different pyrazine formation. It was found that exogenous Ala exhibited a priority in capturing glyoxal (GO) to form pyrazine during the thermal degradation of ARP. Compared to the Ala-methylglyoxal (MGO) model, a lower activation energy was required for the Ala-GO reaction, where the reaction dynamics of Ala-GO followed a zero-order model. In addition to forming pyrazine, the interaction between existing exogenous Ala and GO would accelerate the thermal degradation of Ala-ARP and retro-aldolization reaction of deoxyxylosones (DXs) to α-dicarbonyls. During this process, the release of regenerated Ala and MGO was promoted. Accordingly, as GO was expended by exogenous Ala during the initial stage of ARP-Ala degradation, the condensation between regenerated Ala and MGO became intensified, leading to the generation of methylpyrazine and 2,5-dimethylpyrazine. As a result, in the thermally treated mixture of Ala-ARP and exogenous Ala, 55% of the formed pyrazine originated from exogenous Ala, while 63% of the formed methylpyrazine and 57% of the formed 2,5-dimethylpyrazine were derived from regenerated Ala (120 °C, 30 min).

2.
Food Chem ; 460(Pt 1): 140503, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39053279

RESUMEN

The aim of this study was to investigate the distribution pattern and migration pathway of sodium ion in the myofibrillar protein (MP) gel matrix during microwave heating. The results showed that the content of sodium ions in the outer layer of MP gel increased by 47.85% compared with that in the inner layer. In the inner layer of protein gel, the non-covalent disulfide bonds (mainly ε(γ-Glu)-Lys) increased (P < 0.05), which contributed to the formation of a better rigid structure of the protein. The free water content was significantly higher than that of the inner layer (P < 0.05), which was related to the higher mobility of sodium ions. The results of microstructure analysis showed that the outer layer of the MP gel formed a more porous network than the inner layer. This work is expected to give some insights into the development of promising salt-reduced meat products by microwave heating.

3.
Sensors (Basel) ; 24(14)2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39066138

RESUMEN

Without a well-defined energy management plan, achieving meaningful improvements in human lifestyle becomes challenging. Adequate energy resources are essential for development, but they are both limited and costly. In the literature, several solutions have been proposed for energy management but they either minimize energy consumption or improve the occupant's comfort index. The energy management problem is a multi-objective problem where the user wants to reduce energy consumption while keeping the occupant's comfort index intact. To address the multi-objective problem this paper proposed an energy control system for a green environment called PMC (Power Management and Control). The system is based on hybrid energy optimization, energy prediction, and multi-preprocessing. The combination of GA (Genetic Algorithm) and PSO (Particle Swarm Optimization) is performed to make a fusion methodology to improve the occupant comfort index (OCI) and decrease energy utilization. The proposed framework gives a better OCI when compared with its counterparts, the Ant Bee Colony Knowledge Base framework (ABCKB), GA-based prediction framework (GAP), Hybrid Prediction with Single Optimization framework (SOHP), and PSO-based power consumption framework. Compared with the existing AEO framework, the PMC gives practically the same OCI but consumes less energy. The PMC framework additionally accomplished the ideal OCI (i-e 1) when compared with the existing model, FA-GA (i-e 0.98). The PMC model consumed less energy as compared to existing models such as the ABCKB, GAP, PSO, and AEO. The PMC model consumed a little bit more energy than the SOHP but provided a better OCI. The comparative outcomes show the capability of the PMC framework to reduce energy utilization and improve the OCI. Unlike other existing methodologies except for the AEO framework, the PMC technique is additionally confirmed through a simulation by controlling the indoor environment using actuators, such as fan, light, AC, and boiler.

4.
Food Chem ; 459: 140335, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38981383

RESUMEN

The characteristic aroma compounds of traditional braised pork were investigated by gas chromatography-mass spectrometry-olfactometry (GC-MS-O), odor-activity values, and aroma recombination and omission experiments. A total of 56 volatile compounds were detected by GC-MS, among which hexanal, octanal, nonanal, (E)-2-octenal, 2,3-octanedione, 1-octen-3-ol, 2-pentylfuran, methanethiol, and dimethyl trisulfide were identified as the key aroma compounds by molecular sensory science. Partial least squares regression analysis indicated that some aroma compounds significantly contributed to fatty (hexanal, heptanal, 2-pentylfuran, nonanal, and (E)-2-octenal), meaty (methanethiol, dimethyl disulfide, dimethyl trisulfide, and octanal), sauce-like flavor (3-hydroxy-2-butanone and 2-furfural), and sweet, caramel (2,3-octanedione, 1-octen-3-ol). Lean meat produced more aldehydes, alcohols, ketones, and sulfur-containing compounds than subcutaneous fat. The seasonings (saccharose, cooking wine, and soy sauce) facilitated the formation of ethyl L-lactate, 2-acetylfuran, 2-furfural, 5-methyl-2-furaldehyde, 2-methyl-pyrazine, and 2-acetylpyrrole. Meanwhile they reduced the content of lipid oxidation products, thereby stimulated the characteristic aroma of the Chinese traditional braised pork.

5.
J Agric Food Chem ; 72(30): 16930-16940, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39038222

RESUMEN

Lysine (Lys) is capable of forming a di-substituted Amadori rearrangement product (ARP) with xylose (Xyl), designated as diXyl-α,ε-Lys-ARP. DiXyl-α,ε-Lys-ARP degradation was characterized by two steps: Initially, Xyl-α- and Xyl-ε-Lys-ARP were formed through elimination or hydrolysis at specific Nα/Nε positions of the corresponding enol and imine intermediates, which were then further degraded to dicarbonyl compounds and regenerated Lys. Xyl-α- or Xyl-ε-Lys-ARP had a reactive free amino group (ε-NH2 or α-NH2), both of which were still highly reactive and able to undergo further reactions with Xyl. Therefore, the diXyl-α,ε-Lys-ARP/Xyl model system was established to explore the impact of extra-added Xyl on diXyl-α,ε-Lys-ARP degradation behavior. Extra-added Xyl remarkably affected the degradation pathway of diXyl-α,ε-Lys-ARP by capturing the Xyl-α- and Xyl-ε-Lys-ARP to regenerate diXyl-α,ε-Lys-ARP. This interaction between Xyl and mono-substituted Lys-ARPs promoted the shift of chemical equilibrium toward the degradation of diXyl-α,ε-Lys-ARP, thereby accelerating its degradation rate. This degradation was markedly facilitated by the elevated temperature and pH values. Interestingly, the yield of Xyl-α- and Xyl-ε-Lys-ARP was particularly dependent on the pH during diXyl-α,ε-Lys-ARP degradation. Xyl-ε-Lys-ARP was the dominant product at pH 5.5-7.5 while Xyl-α-Lys-ARP possessed a relatively higher content under weak alkaline conditions, which was related to the reactivities of the Nα/Nε positions under various reaction conditions.


Asunto(s)
Lisina , Reacción de Maillard , Xilosa , Xilosa/química , Lisina/química , Hidrólisis , Cinética , Calor
6.
Food Res Int ; 188: 114506, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38823846

RESUMEN

The characteristic aroma compounds of braised pork were identified through molecular sensory science and PLSR analysis, and the difference between two cooking methods, traditional open-fire (BPF) and induction cooker (BPC), was compared. Seventeen aroma compounds with odor activity values (OAVs) > 1 were identified in both samples. BPF revealed higher OAVs for most of the aroma compounds compared to BPC, and the higher aroma quality. Aroma recombination and omission experiments confirmed that twelve aroma compounds significantly contributed to the characteristic aroma of braised pork, and eight compounds such as hexanal, (E)-2-octenal, and methanethiol were further confirmed as important contributors by PLSR analysis. Furthermore, PLSR analysis clarified the role of aldehydes such as hexanal, (E)-2-octenal, and (E,E)-2,4-decadienal in contributing to fatty attribute, whereas methanethiol was responsible for the meaty aroma. These characteristic aroma compounds mainly derived from lean meat due to its high content of phospholipids, and the exogenous seasonings contributed to the balanced characteristic aroma profile of braised pork by altering the distribution of these characteristic aroma compounds. Variations in heating parameters affected the formation of lipid oxidation and Strecker degradation products, which might explain aroma discrepancy between braised pork cooked by two methods with different heat transfer efficiencies.


Asunto(s)
Aldehídos , Culinaria , Odorantes , Culinaria/métodos , Odorantes/análisis , Animales , Porcinos , Aldehídos/análisis , Compuestos Orgánicos Volátiles/análisis , Carne de Cerdo/análisis , Humanos , Compuestos de Sulfhidrilo/análisis
7.
Heliyon ; 10(5): e27323, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38562496

RESUMEN

Every problem in decision-making has a solution when the information that is available is properly and precisely modeled. This study focuses on non-binary data from N-soft sets and q-rung orthopair fuzzy values, referred to as group-based generalized q-rung orthopair fuzzy N-soft sets (GGq-ROFNSSs). The GGq-ROFNSSs model provides information simultaneously on numerous competing criteria, alternatives, sub-alternatives, and data summarization. We introduce properties of GGq-ROFNSSs such as distinct inclusion features of GGq-ROFNSSs, weak complements of the GGq-ROFNSS, top weak complements the GGq-ROFNSS, bottom weak complements the GGq-ROFNSS. We provide the notion of GGq-ROFNSWA and GGq-ROFNSWG operators as well as their idempotency, monotonicity, and boundedness features. The notion of GGq-ROFNSSs requires a sound methodology of multiple criteria decision making (MCDM) since GGq-ROFNSS combines numerous elements of complex decision-making. We provide a MCDM methodology for the GGq-ROFNSWA and GGq-ROFNSWG operators and depict it in a flowchart. The selection of solar panels for a city is a difficult procedure because it depends on several components such as environment, where the area is located, what kinds of needs are being met, etc. We find a solution to the problem of selecting a suitable solar panel for a city with their underlying characteristics. Finally, we provide a comparison of the suggested method with other techniques to demonstrate its advantages.

8.
ACS Omega ; 9(11): 13208-13216, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38524435

RESUMEN

Silver nanoparticles (Ag-NPs) were synthesized by using the polyol method. The structural and morphological characteristics of Ag-NPs were studied by using X-ray diffraction (XRD) and field-emission scanning electron microscopy (FE-SEM). The XRD analysis revealed the formation of single-phase polycrystalline Ag-NPs with an average crystallite size and lattice constant of ∼23 nm and 4.07 Å, respectively, while the FE-SEM shows the formation of a uniform and spherical morphology. Energy-dispersive X-ray spectroscopy confirmed the formation of single-phase Ag-NPs, and no extra elements were detected. A strong absorption peak at ∼427 nm was observed in the UV-vis spectrum, which reflects the surface plasmon resonance (SPR) behavior characteristic of Ag-NPs with a spherical morphology. Fourier-transform infrared (FTIR) spectra also supported the XRD and EDX results with regard to the purity of the prepared Ag-NPs. Anti-inflammatory activity was tested using HRBCs membrane stabilization and heat-induced hemolysis assays. The antibacterial activity of Ag-NPs was evaluated against four different types of pathogenic bacteria by using the disc diffusion method (DDM). The Gram-negative bacterial strains used in this study are Escherichia coli (E. coli), Klebsiella, Shigella, and Salmonella. The analysis suggested that the antibacterial activities of Ag-NPs have an influential role in inhibiting the growth of the tested Gram-negative bacteria, and thus Ag-NPs can find a potential application in the pharmaceutical industry.

9.
J Agric Food Chem ; 72(12): 6554-6564, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38498924

RESUMEN

Dihydromyricetin (DMY) was employed to reduce the yield of furfural derived from the Amadori rearrangement product of l-threonine and d-xylose (Thr-ARP) by trapping Thr-ARP, 3-deoxyxyosone (3-DX), and furfural to form adducts. The effect of different concentrations of DMY at different pH values and temperatures on the reduction of furfural production was studied, and the results showed that DMY could significantly reduce furfural production at higher pH (pH 5-7) and lower temperature (110 °C). Through the surface electrostatic potential analysis by Gaussian, a significant enhancement of the C6 nucleophilic ability at higher pH (pH ≥ 5) was observed on DMY with hydrogen-dissociated phenol hydroxyl. The nucleophilic ability of DMY led to its trapping of Thr-ARP, 3-DX, and furfural with the generation of the adducts DMY-Thr-ARP, DMY-3-DX, and DMY-furfural. The formation of the DMY-Thr-ARP adduct slowed the degradation of Thr-ARP, caused the decrease of the 3-DX yield, and thereby inhibited the conversion of 3-DX to furfural. Therefore, DMY-Thr-ARP was purified, and the structure was identified by nuclear magnetic resonance (NMR). The results confirmed that C6 or C8 of DMY and carbonyl carbon in Thr-ARP underwent a nucleophilic addition reaction to form the DMY-Thr-ARP adduct. In combination with the analysis results of Gaussian, most of the DMY-Thr-ARP adducts were calculated to be C6-DMY-Thr-ARP. Furthermore, the formation of DMY-furfural caused furfural consumption. The formation of the adducts also shunted the pathway of both Thr-ARP and 3-DX conversion to furfural, resulting in a decrease in the level of furfural production.


Asunto(s)
Furaldehído , Xilosa , Xilosa/química , Temperatura , Flavonoles/química
10.
J Agric Food Chem ; 72(11): 5878-5886, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38462902

RESUMEN

The involvement of exogenous alanine was observed to inhibit the generation of 2-furfural during the thermal degradation of the Amadori rearrangement product (ARP). To clarify the reason for the reduced yield of 2-furfural triggered by exogenous alanine, the evolution of the precursors of 2-furfural formed in the ARP model and ARP-alanine model was investigated, and a model including ARP and 15N-labeled alanine was used to differentiate the role of endogenous and exogenous alanine in the degradation of ARP. It was found that the condensation between ARP and 3-deoxyxylosone could occur during thermal treatment. Nevertheless, the interaction of ARP with 3-deoxyxylosone exhibited an accelerated pace in the presence of exogenous alanine. In this way, exogenous alanine blocked the recovery of endogenous alanine while simultaneously enhancing the consumption of ARP and 3-deoxyxylosone during the Maillard reaction. Hence, the yield of 2-furfural was diminished with the interference of exogenous alanine. Furthermore, the promotion of the reaction between ARP and deoxyxylosone induced by exogenous alanine blocked their retro-aldolization reaction to short-chain α-dicarbonyls (α-DCs) and consequently resulted in a lack of pyrazine formation during the ARP degradation. The present study provided a feasible method for the controlled formation of 2-furfural during the thermal treatment of ARP derived from alanine.


Asunto(s)
Alanina , Furaldehído , Reacción de Maillard
11.
RSC Adv ; 14(2): 1018-1033, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38174269

RESUMEN

In the present work, a small library of novel pyrazolinyl-acyl thiourea (5a-j) was designed and synthesized through a multistep sequence and the synthesized compounds were screened for their antifungal, antibacterial and antioxidant activities as well as urease, amylase and α-glucosidase inhibitory activities. The synthesized series (5a-o) was characterized using a combination of spectroscopic techniques, including FT-IR, 1H NMR and 13C NMR. All compounds (5a-j) were found to have significant potency against urease, α-glucosidase, α-amylase, and DPPH. The synthesized compounds were also screened for potential antibacterial and anti-fungal inhibition activities. IC50 values for all the prepared compounds for urease, α-glucosidase, amylase, and DPPH inhibition were determined and derivatives 5b and 5g were found to be the most potent urease inhibitors with IC50 values of 54.2 ± 0.32 and 43.6 ± 0.25 µM, respectively. Whilst compound 5b (IC50 = 68.3 ± 0.11 µM) is a potent α-glucosidase inhibitor, compound 5f (90.3 ± 1.08 µM) is a potent amylase inhibitor and compound 5b (103.4 ± 1.15 µM) is a potent antioxidant. The different substitutions on the phenyl ring were the basis for structure-activity relationship (SAR) study. The molecular docking study was performed for the confirmation of binding interactions.

12.
Int J Biol Macromol ; 259(Pt 2): 129410, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38219931

RESUMEN

The intense bitterness of quercetin poses a challenge to its utilization in the food industry. To address this issue, three anionic polysaccharides (carrageenan, pectin, and trehalose) were individually incorporated to fabricate polysaccharide-coated liposome nanocarriers. Electronic tongue analysis revealed a significant decreasing bitterness value (10.34 ± 0.07 mV, sensory score 1.8 ± 0.2, taste weak bitter) in quercetin-loaded nanoliposomes, compared with the bitterness value of quercetin aqueous solution (14 ± 0.01 mV, sensory score 7.3 ± 0.3, taste strong bitter). Furthermore, the polysaccharide-coated nanoliposomes exhibited an even greater capacity to mask the bitterness of quercetin, with carrageenan coated nanoliposomes demonstrating the most pronounced effect. The superior bitter masking ability of carrageenan coated nanoliposomes can be attributed to its high charge and viscosity. In sensory evaluations, gummy incorporated with carrageenan-coated nanoliposomes received the highest ratings, exhibiting enhanced overall palatability and antioxidant activity. This study offers insights into expanding the use of bitter nutrients in food applications and paves the way for more appealing and healthful food products.


Asunto(s)
Pectinas , Gusto , Carragenina , Pectinas/farmacología , Quercetina/farmacología , Trehalosa , Polisacáridos/farmacología
13.
RSC Adv ; 14(4): 2402-2409, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38213969

RESUMEN

The objective of this research was to produce the smallest possible ZnO nanoparticles through an adapted wet chemical process and subsequently, to fabricate a core-shell structure utilizing polyethylene glycol (PEG) as the shell component. The synthesis, size, and shape of the NPs were confirmed using advanced techniques. The resulting clustered NPs were round and had a size of 9.8 nm. Both plain and core-shell NPs were tested for their antibacterial properties against multi-drug resistant bacteria strains (E. cloacae, E. amnigenus, S. flexneri, S. odorifacae, Citrobacter, and E. coli), with concentrations of 500, 1000, and 1500 µg ml-1 used for testing. Both types of NPs demonstrated antibacterial activity against the tested pathogens, with the core-shell NPs being more effective. The synthesized NPs were biocompatible with human red blood cells, with a low level of hemolysis observed. The biocompatibility of the core-shell NPs was significantly enhanced by the presence of the PEG added as the shell. In addition, their effectiveness as photosensitizers for cancer treatment via photodynamic therapy (PDT) was evaluated. MTT assay was used to evaluate the cytotoxicity of ZnO and PEG-ZnO, and the results showed that these NPs were able to generate ROS inside tumor cells upon irradiation, leading to apoptosis and cell death, making them a promising candidate for PDT.

14.
J Agric Food Chem ; 72(1): 647-656, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38115213

RESUMEN

Until now, no effective method has been found to monitor the Maillard reaction process for complex protein hydrolysates. Dynamic changes in the concentration of α-dicarbonyl compounds, fluorescence intensity, and browning degree were investigated during the Maillard reaction of corn protein hydrolysates. When the fluorescence intensity reached the peak, deoxyosones would continue to be increased by ARP's degradation. However, the reaction node with the highest fluorescence intensity coincided with the turning point of the browning reaction, and the subsequent browning rate remarkably increased. Therefore, the change in fluorescence intensity could be used to monitor the degradation of ARP and the formation of browning melanoidin at different stages of the Maillard reaction of complex systems, thus effectively indicating the process of the Maillard reaction. When Maillard reaction intermediates (MRIs) with maximum fluorescent compounds were heated, the most abundant pyrazines were subsequently achieved. However, furan compounds would be progressively increased during the thermal process of MRIs with continuously enhanced browning.


Asunto(s)
Reacción de Maillard , Xilosa , Zea mays , Hidrolisados de Proteína , Calor
15.
Carbohydr Polym ; 326: 121658, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38142086

RESUMEN

Physical stability and lipid digestion of protein-stabilized Pickering emulsions interacting with polysaccharides have been emphasized in our previous investigation. However, the polysaccharide coating and micelle protection of protein-based stable Pickering emulsion and its three-dimensional (3D) printing properties have not been thoroughly studied. The rheological properties and 3D printing properties of gelatin-catechin nanoparticles (GCNPs) stabilized Pickering emulsion were studied by using different charged polysaccharides, such as inulin (neutral), Xanthan gum (XG, anion), and chitosan (cation) as stable materials. The microstructure analysis of polysaccharide-stabilized Pickering emulsion (PSPE) showed that the order of pore wall thickness was GC-Chitosan > GC-XG > GC-Inulin. The network structure of GC-Chitosan was thickened, allowing the 3D printed product to have a good surface texture and adequate support. Rheological analysis showed that PSPEs in extrusion (shear thinning), self-support (rigid structure), and recovery (the outstanding thixotropy) of the three stages exhibited good potential of 3D printing. 3D printing results also showed that GC-Chitosan had the best printing performance. Therefore, polysaccharide-stabilized Pickering emulsions can provide a basis for the development of 3D printed food products.


Asunto(s)
Quitosano , Inulina , Emulsiones/química , Quitosano/química , Polisacáridos Bacterianos/química , Impresión Tridimensional
16.
J Agric Food Chem ; 71(50): 20251-20259, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38060299

RESUMEN

The browning formation and taste enhancement of peptides derived from soybean, peanut, and corn were studied in the light-colored Maillard reaction compared with the deep-colored reaction. The fluorescent compounds, as the browning precursors, were accumulated during the early Maillard reaction of peptides and subsequently degraded into dark substances, which resulted in a higher browning degree of deep-colored Maillard peptides (MPs), especially for the MPs derived from corn peptide. However, the addition of l-cysteine in light-colored Maillard reaction reduced the formation of deoxyosones and short-chain reactive α-dicarbonyls, thereby weakening the generation of fluorescent compounds and inhibited the browning of MPs. Synchronously, the peptides were thermally degraded into small peptides and amino acids, which were consumed less during light-colored thermal reaction due to its shorter reaction time at high temperature compared with deep-colored ones, thus contributing to a stronger saltiness perception of light-colored MPs than deep-colored MPs. Besides, the Maillard reaction products derived from soybean and peanut peptides possessed an obvious "kokumi" taste, making them suitable for enhancing the soup flavors.


Asunto(s)
Reacción de Maillard , Péptidos , Péptidos/química , Aminoácidos/química , Cisteína/química , Glycine max , Percepción
17.
J Agric Food Chem ; 71(46): 17874-17885, 2023 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-37939699

RESUMEN

The efficient preparation of the ribose-glutathione (Rib-GSH) Amadori rearrangement product (RG-ARP) as a potent precursor of meaty flavor was studied through the atmospheric-vacuum thermal reaction. Liquid chromatography-mass spectrometry (LC-MS) analysis revealed that the oxidation and degradation of GSH occurred during the preparation of RG-ARP via the atmospheric thermal reaction, especially at a low molar ratio of Rib to GSH and high reaction temperature. The RG-ARP and the ARPs derived from the products of GSH oxidation and degradation with the participation of Rib were identified by MS/MS as N-(1-deoxy-d-ribulos-1-yl)-glutathione, N-(1-deoxy-d-ribulos-1-yl)-cysteinylglycine, and N-(1-deoxy-d-ribulos-1-yl)-glutathione disulfide. The selective formation of RG-ARP was disrupted due to the multiple consumption pathways of GSH and Rib. The removal of water and the reduction of oxygen content during vacuum dehydration exhibited an obvious inhibitory effect on the oxidation of cysteinyl and the cleavage of glutamyl, limiting the oxidation and degradation of GSH. Meanwhile, the rapid evaporation of water promoted the molecular collision between the reactants, which allowed the glycation reaction of GSH to be advanced and fragmentation of RG-ARP to be inhibited at a mild dehydration temperature. Accordingly, the atmospheric-vacuum thermal reaction was proposed to limit the generation of secondary byproducts and enhance the yield of RG-ARP, enabling the RG-ARP yield to reach 49.23% at 80 °C and a molar ratio of 2:1 (Rib/GSH) for 20 min.


Asunto(s)
Deshidratación , Espectrometría de Masas en Tándem , Humanos , Vacio , Glutatión/química , Reacción de Maillard , Agua/química
18.
ACS Appl Mater Interfaces ; 15(47): 54432-54445, 2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-37968934

RESUMEN

The commercialization of ultrahigh capacity lithium-oxygen (Li-O2) batteries is highly dependent on the cathode architecture, and a better understanding of its role in species transport and solid discharge product (i.e., Li2O2) formation is critical to improving the discharge capacity. Tailoring the pore size distribution in the cathode structure can enhance the ion mobility and increase the number of reaction sites to improve the formation of solid Li2O2. In this work, the potential of hierarchical zeolite-templated carbon (ZTC) structures as novel electrodes for Li-O2 batteries was investigated by using reactive force field molecular dynamics simulation (reaxFF-MD). Initially, 47 microporous zeolite-templated carbon morphologies were screened based on microporosity and specific area. Among them, four structures (i.e., RHO-, BEA-, MFI-, and FAU-ZTCs) were selected for further investigation including hierarchical features in their structures. Discharge product cluster analysis, self-diffusivities, and density number profiles of Li+, O2, and dimethyl sulfoxide (DMSO) electrolyte were obtained to find that the RHO-type ZTC exhibited enhanced mass transfer compared to conventional microporous ZTC (approximately 31% for O2, 44% for Li+, and 91% for DMSO) electrodes. This is due to the promoted formation of small-sized product clusters, creating more accessible sites for oxygen reduction reaction and mass transport. These findings indicate how hierarchical ZTC electrodes with micro- and mesopores can enhance the discharge performance of aprotic Li-O2 batteries, providing molecular insights into the underlying phenomena.

19.
J Agric Food Chem ; 71(43): 16260-16269, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37857511

RESUMEN

2-Threityl-thiazolidine-4-carboxylic acid (TTCA) and Amadori rearrangement product (ARP), the isomeric intermediates derived from the cysteine-xylose (Cys-Xyl) Maillard reaction model, possessed the ability to produce similar flavor profile during the thermal process, but the flavor formation or browning rate of heated TTCA was significantly lower than that of ARP. Macroscopically, the yield of TTCA reached the maximum when the moisture content of the reaction system just dropped to nearly 0% during the thermal reaction-vacuum dehydration process. During the subsequent dynamic intramolecular dehydration process, the reaction remained at an early stage of the Maillard reaction, and TTCA was the main intermediate. Thereinto, the water activity of the samples decreased with the increased dehydration time. From a molecular perspective, the dissipation of free water promoted the conversion of combined water to immobilized water and free water, increasing the intramolecular dehydration. Instantaneous high-temperature dehydration during the spray drying process revealed a higher efficiency than the thermal reaction-vacuum dehydration process, which facilitated the specific conversion of substrates to intermediates (TTCA, ARP). The loss of free water and immobilized water was a key driving force for the direct formation of TTCA/ARP, regulating the formation stages of MRIs. The increase of the inlet air temperature could alter the ratio of TTCA and ARP at the equilibrium state.


Asunto(s)
Reacción de Maillard , Xilosa , Humanos , Xilosa/química , Cisteína/química , Deshidratación , Agua
20.
Sensors (Basel) ; 23(20)2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-37896745

RESUMEN

In the early 1990s, Mehrotra and Nichani developed a filtering-based corner detection method, which, though conceptually intriguing, suffered from limited reliability, leading to minimal references in the literature. Despite its underappreciation, the core concept of this method, rooted in the half-edge concept and directional truncated first derivative of Gaussian, holds significant promise. This article presents a comprehensive assessment of the enhanced corner detection algorithm, combining both qualitative and quantitative evaluations. We thoroughly explore the strengths, limitations, and overall effectiveness of our approach by incorporating visual examples and conducting evaluations. Through experiments conducted on both synthetic and real images, we demonstrate the efficiency and reliability of the proposed algorithm. Collectively, our experimental assessments substantiate that our modifications have transformed the method into one that outperforms established benchmark techniques. Due to its ease of implementation, our improved corner detection process has the potential to become a valuable reference for the computer vision community when dealing with corner detection algorithms. This article thus highlights the quantitative achievements of our refined corner detection algorithm, building upon the groundwork laid by Mehrotra and Nichani, and offers valuable insights for the computer vision community seeking robust corner detection solutions.

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