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1.
Ultrason Sonochem ; 105: 106856, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38554530

RESUMO

The residue remaining after oil extraction from grape seed contain abundant procyanidins. An ultrasonic-assisted enzyme method was performed to achieve a high extraction efficiency of procyanidins when the optimal extraction conditions were 8 U/g of cellulase, ultrasound power of 200 W, ultrasonic temperature of 50 ℃, and ultrasonic reaction time of 40 min. The effects of free procyanidins on both radical scavenging activity and thermal stability at 40, 60, and 80 ℃ of the procyanidins-loaded liposomal systems prepared by the ultrasonic-assisted method were discussed. The presence of procyanidins at concentrations ranging from 0.02 to 0.10 mg/mL was observed to be effective at inhibiting lipid oxidation by 15.15 % to 69.70 % in a linoleic acid model system during reaction for 168 h, as measured using the ferric thiocyanate method. The procyanidins-loaded liposomal systems prepared by the ultrasonic-assisted method were characterized by measuring the mean particle size and encapsulation efficiency. Moreover, the holographic plots showed that the effect-response points of procyanidins combined with α-tocopherol in liposomes were lower than the addition line and 95 % confidence interval limits. At the same time, there were significant differences between the theoretical IC50add value and the experimental IC50mix value. The interaction index (γ) of all combinations was observed to be less than 1. These results indicated that there was a synergistic antioxidant effect between procyanidins combined with α-tocopherol, which will show promising prospects in practical applications. In addition, particle size differentiation and morphology agglomeration were observed at different time points of antioxidant activity determination (0, 48, 96 h).


Assuntos
Antioxidantes , Lipossomos , Proantocianidinas , Proantocianidinas/isolamento & purificação , Proantocianidinas/química , Lipossomos/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Ondas Ultrassônicas , Vitis/química , Extrato de Sementes de Uva/química , Fracionamento Químico/métodos , Tamanho da Partícula , Temperatura , Sementes/química
2.
Food Chem ; 444: 138633, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38330607

RESUMO

The present study focused on investigating the stability and in vitro simulation characteristics of oil-in-water (O/W) and oleogel-in-water (Og/W) emulsions. Compared with O/W emulsion, the Og/W emulsion exhibited superior stability, with a more evenly spread droplet distribution, and the Og/W emulsion containing 3 % hemp seed protein (HSP) showed better stability against environmental factors, including heat treatment, ionic strength, and changes in pH. Additionally, the stability of Δ9-tetrahydrocannabinol (Δ9-THC) and cannabinol (CBN) and the in vitro digestion of hemp seed oil (HSO) were evaluated. The half-life of CBN in the Og/W emulsion was found to be 131.82 days, with a degradation rate of 0.00527. The in vitro simulation results indicated that the Og/W emulsion effectively delayed the intestinal digestion of HSO, and the bioaccessibility of Δ9-THC and CBN reached 56.0 % and 58.0 %, respectively. The study findings demonstrated that the Og/W emulsion constructed with oleogel and HSP, exhibited excellent stability.


Assuntos
Cannabis , Extratos Vegetais , Cannabis/metabolismo , Emulsões/metabolismo , Canabinol , Dronabinol , Água , Compostos Orgânicos
3.
Ultrason Sonochem ; 103: 106766, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38271781

RESUMO

In this study, ultrasonic-ethanol pretreatment combined with AEE was developed for oil extraction from hemp seeds. The oil yield reached a maximum of 23.32 % at 200 W ultrasonic power and 30 min ultrasonic time, at this point, the degradation rate of Δ9-THC was 83.11 %. By determining the composition of hemp seed before and after pretreatment, it was shown that ultrasonic-ethanol pretreatment reduced the protein content of the raw material. An enzyme mixture consisting of pectinase and hemicellulase (1/1/1, w/w/w) was experimentally determined to be used, and the AEE extraction conditions were optimized using the Plackett-Burman design and the Box-Behnken. The optimal conditions were determined to be pH 5, total enzyme activity of 37,800 U/g, liquid-solid ratio of 10.4 mL/g, enzyme digestion temperature of 32 °C, enzymatic time of 189 min, and oil recovery of 88.38 %. The results of confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) showed that the emulsion formed during ultrasonic ethanol pretreatment was not uniformly distributed, and the droplets appeared to be aggregated; and the irregular pores of hemp seed increased after pretreatment. The contents of Δ9-THC and CBN in the extracted oil samples were 9.58 mg/kg and 52.45 mg/kg, respectively. Compared with the oil extracted by Soxhlet extraction (SE), the oil extracted by this experimental method was of better quality and similar in fatty acid composition.


Assuntos
Cannabis , Extratos Vegetais , Cannabis/química , Ultrassom , Dronabinol/análise , Etanol/análise , Sementes/química , Água/química , Óleos de Plantas/química
4.
Int J Biol Macromol ; 259(Pt 2): 129217, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38184043

RESUMO

In this investigation, soybean protein isolate-rutin (SPI-RT) complexes were treated using dynamic high-pressure microfluidization (DHPM). The effects of this process on the physicochemical and thermodynamic properties of SPI were investigated at different pressures. Fourier-transform infrared spectroscopy and fluorescence spectroscopy provided evidence that the SPI structure had been altered. The binding of SPI to RT resulted in a decrease in the percentage of α-helices and random curls as well as an increase in the percentage of ß-sheets. In particular, the α-helix content decreased from 29.84 % to 26.46 %, the random curl content decreased from 17.45 % to 15.57 %, and the ß-sheet content increased from 25.37 % to 26.53 %. Moreover, fluorescence intensity decreased, and the emission peak of the complex was red-shifted by 6 nm, exposing the internal groups. Based on fluorescence quenching analysis, optimal SPI-RT complexation was achieved after 120-MPa DHPM treatment, and molecular docking analysis verified the interaction between SPI and RT. The minimum particle size, maximum absolute potential, and total phenolic content of the complexes were 78.06 nm, 21.4 mV and 74.35 nmol/mg protein, respectively. Furthermore, laser confocal microscopy revealed that the complex particles had the best microstructure. Non-covalent interactions between the two were confirmed using sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Moreover, the hydrophobicity of the complex particle's surface increased to 16,045 after 120-MPa DHPM treatment. The results of this study suggest that DHPM strongly promotes the improvement of the physicochemical properties of SPI, and provide a theoretical groundwork for further research.


Assuntos
Proteínas de Soja , Proteínas de Soja/química , Simulação de Acoplamento Molecular , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Interações Hidrofóbicas e Hidrofílicas
5.
Int J Biol Macromol ; 257(Pt 1): 128804, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38101664

RESUMO

In this paper, using a coprecipitation method to prepare Fe3O4 magnetic nanoparticles (Fe3O4 MNPS), magnetic dialdehyde starch nanoparticles with immobilized phospholipase A1 (MDSNIPLA) were successfully prepared by using green dialdehyde starch (DAS) instead of glutaraldehyde as the crosslinking agent. The Fe3O4 MNPS was characterized by infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), the Brunauer-Emmett-Teller (BET) surface area analysis method, thermogravimetric analysis (TGA), and transmission electron microscopy (TEM) et al. The results showed that the alkaline resistance and acid resistance of the enzyme were improved after the crosslinking of DAS. After repeated use (seven times), the relative activity of MDSNIPLA reached 56 %, and the magnetic dialdehyde starch nanoparticles (MDASN) had good carrier performance. MDSNIPLA was applied to enzymatic hydrolysis of phospholipids in the soybean oil degumming process. The results showed that the acyl transfer rate of sn-2-HPA was 14.01 %, and the content of free fatty acids was 1.144 g/100 g after 2 h reaction at 50 °C and pH 5.0 with appropriate boric acid. The immobilized enzyme has good thermal stability and storage stability, and its application of soybean oil improves the efficiency of the oil.


Assuntos
Enzimas Imobilizadas , Óleo de Soja , Amido/análogos & derivados , Espectroscopia de Infravermelho com Transformada de Fourier , Enzimas Imobilizadas/química , Fosfolipases , Fenômenos Magnéticos
6.
Ultrason Sonochem ; 101: 106675, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37925914

RESUMO

This research explored the influences of ultrasonic and thermal treatments on the structure, functional properties, and beany flavor of soy protein isolate (SPI). In comparison with traditional thermal treatment, ultrasonic treatment effectively induced protein structural unfolding and exposure of hydrophobic groups, which reduced relative content of α-helix, increased relative content of ß-turn, ß-sheet and random coil, and improved the solubility, emulsifying and foaming properties of SPI. Both treatments significantly decreased the species and contents of flavor compounds, such as hexanal, (E)-2-nonenal, (Z)-2-heptenal and (E)-2-hexenal in SPI. The relative content of hexanal in the major beany flavor compound decreased from 11.69% to 6.13% and 5.99% at 350 W ultrasonic power and 150 s thermal treatment procedure, respectively. After ultrasonic treatment, structural changes in SPI were significantly correlated with functional properties but showed a weak correlation with flavor. Conversely, the opposite trend was observed for thermal treatment. Thus, using ultrasonic treatment to induce and stabilise the denatured state of proteins is feasible to improve the functional properties and beany flavor of SPI.


Assuntos
Proteínas de Soja , Ultrassom , Proteínas de Soja/química , Interações Hidrofóbicas e Hidrofílicas
7.
J Oleo Sci ; 72(5): 521-531, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37121677

RESUMO

Using sunflower oil as the oil matrix, the antioxidant effects and types of interactions of three natural components, α-tocopherol, ß-carotene and epigallocatechin gallate (EGCG), were investigated and the kinetic model of oxidation reaction was established. The results showed that the ability of the three antioxidants to scavenge DPPH radicals was ranked as EGCG > ß-carotene > α-tocopherol in the concentration range of 0~100 mg/kg. 15 samples were obtained by combining two of three natural components. When the concentration ratios of ß-carotene and EGCG were 1:20 and 1:7.5, α-tocopherol and EGCG were 1:13.3, 1:6, and 1:2, and α-tocopherol and ß-carotene were 1:0.2 and 1:0.05, the type of interaction was synergistic, while the rest of the samples showed antagonistic effects. The sample with a 1:13.3 concentration of α-tocopherol and EGCG showed the longest induction period, the lowest oxidation rate constant, the highest activation energy, the best oxidative stability, and the longest shelf life at different temperatures. This compounded natural antioxidant was the most favorable for the stability of sunflower oil. This provides some theoretical basis for the development and application of compounded natural antioxidants in vegetable oils.


Assuntos
Antioxidantes , alfa-Tocoferol , Antioxidantes/farmacologia , beta Caroteno , Óleo de Girassol , Oxirredução , Estresse Oxidativo
8.
Food Chem ; 404(Pt A): 134520, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36444032

RESUMO

Rice bran wax was added to hemp seed oil (HSO) to prepare oleogel, and hemp seed protein isolate (HPI)-phosphatidylcholine (PC) was used as the emulsifier to obtain an oleogel-in-water (Og/W) gel system. The effect of HPI concentration on the construction of gel system was studied. Microscopic observations found that the oil droplets were encapsulated by the emulsifier. X-ray diffraction and Fourier transform infrared spectroscopy analysis showed that the increase in HPI concentration promoted the interaction between PC and protein, but didn't affect the crystal structure of gel. Thermogravimetric analysis showed that when the HPI concentration was 8 %, the sample formed a dense gel network and had good thermal stability. At this time, the oil holding capacity of gel was 98.81 ± 0.08 %, and the gel hardness was 109.55 ± 1.74 g. After 30 days of storage, the retention rate of Δ9-THC reached 96.3 %, and the peroxide value was 4.98 mmol/kg.


Assuntos
Cannabis , Água , Lecitinas , Emulsificantes , Sementes
9.
Food Chem ; 404(Pt A): 134568, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36252381

RESUMO

Rice bran oil contains a significant quantity of phytosterols that have various active functions and are natural active substances beneficial to humans. It is well known that deodorization during refining affects the quality of rice bran oil. However, changes in phytosterols fraction caused by stripping with nitrogen compared to water vapor remain unexplored. We measured phytosterols in rice bran oil after deodorization with nitrogen and water vapor. The variations in sitosterol fraction, which accounts for the highest percentage of phytosterols in rice bran oil, were analyzed by Gas chromatography (GC), Fourier transform infrared spectrometer (FTIR), and Nuclear magnetic resonance (NMR). Results showed that using nitrogen as the stripping gas was more suitable for deodorization. It promoted the formation of phytosterol esters, reduced the production of phytosterol oxidation products and improved the oil quality. This study provides a theoretical basis for improving the industrial production quality of rice bran oil.


Assuntos
Fitosteróis , Esteróis , Humanos , Óleo de Farelo de Arroz/química , Vapor , Fitosteróis/análise , Nitrogênio/análise
10.
Food Res Int ; 161: 111845, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36192898

RESUMO

Octenyl succinic acid (OSA)-modified starch was prepared using three kinds of rice starch with different amylose content: glutinous rice starch (GRS, 3.67 g/100 g), japonica rice starch (JRS, 17.61 g/100 g), and indica rice starch (IRS, 27.94 g/100 g). The degree of polymerization of OSA and the starch types was 0.0093, 0.0143, and 0.0159, respectively. In addition, holes and cracks were observed in the starch particles owing to esterification. The OSA modification introduced OS group and affected hydrogen bond, but exerted no effect on the crystal form (A-type). The contact angle and emulsifying index revealed that OSA-JRS exhibited the most promising emulsification effect compared to the other samples. Next, soybean oil was added into the OSA-JRS solution to prepare an oil-water emulsion. The results revealed that compared to natural JRS, OSA-JRS exhibited decreased D4,3 and a more uniform distribution. Additionally, its absolute potential value increased to 21.34 mV. Further, the dynamic interfacial tension and contact angle of the OSA-modified samples decreased, whereas the storage and loss moduli of the emulsion increased. The shear resistance, centrifugal force resistance, and storage stability of the OSA-modified emulsion significantly improved. The results demonstrated the potential of the OSA-modified JRS for preparing stable emulsions.


Assuntos
Oryza , Amido , Amilose/química , Emulsões/química , Oryza/química , Tamanho da Partícula , Óleo de Soja , Amido/química , Ácido Succínico , Água/química
11.
Enzyme Microb Technol ; 161: 110116, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36037553

RESUMO

Glutaraldehyde is usually used as a cross-linking agent in the immobilization of enzymes, but this will have a negative effect on the enzyme. Dialdehyde starch can effectively replace glutaraldehyde as a cross-linking agent, but the large particle size of dialdehyde starch affects the performance of immobilized enzyme. In this study, dialdehyde starch nanoparticles (DSNP) were combined with modified Fe3O4 to obtain magnetic carrier (MDSNP), and Candida Antarctica lipase B (CALB) was crosslinked to the carrier to obtain magnetic immobilized enzyme (MDSNPCALB). The characterization results show that the functional groups of each material have obvious characteristic absorption peaks, strong diffraction peaks and typical crystal structures, high magnetism, no coercivity, relatively good dispersion and nano particle size. MDSNPCALB was added to degummed rice bran oil (RBO) and ethanolamine was used as an acyl receptor for acylation and deacidification. After repeated use for 10 times, MDSNPCALB remained highly active, indicating that MDSNPCALB can be effectively used for the deacidification of RBO.


Assuntos
Enzimas Imobilizadas , Proteínas Fúngicas , Enzimas Imobilizadas/química , Proteínas Fúngicas/química , Glutaral , Fenômenos Magnéticos , Óleo de Farelo de Arroz , Amido/química
12.
Ultrason Sonochem ; 86: 106021, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35512585

RESUMO

In this study, hemp seed oil (HSO) emulsions stabilized with hemp seed protein (HPI) were prepared and treated with high intensity ultrasonic (HIU). The effects of different treatment powers (0, 150, 300, 450, 600 W) on the properties, microstructure and stability of emulsions were investigated. HIU-treated emulsions showed improved emulsifying activity index and emulsifying stability index, reduced particle size, and increased absolute values of ζ-potential, with the extreme points of these indices occurring at a treatment power of 450 W. Here, the emulsion showed the best dispersion and the smallest particle size in fluorescence microscopy observation, with the highest adsorbed protein content (30.12%), and the highest tetrahydrocannabinol (THC) retention rate (87.64%). The best thermal and oxidative stability of the emulsions were obtained under HIU treatment with a power of 450 W. The D43 and the peroxide values (POV) values after 30 d storage were the smallest at 985.74 ± 64.89 nm and 4.6 µmol/L, respectively. Therefore, 450 W was optimal HIU power to effectively improve the properties of HPI-stabilized HSO emulsion and promote the application of HSO and its derivatives in food processing production.


Assuntos
Cannabis , Cannabis/química , Emulsões/química , Tamanho da Partícula , Extratos Vegetais , Sementes/química , Ultrassom
13.
Ultrason Sonochem ; 83: 105945, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35149379

RESUMO

In this study, the three-dimensional network system formed by rice bran wax (RBW) was used as the internal structure, and the external structure formed by soybean protein isolate (SPI) and phosphatidylserine (PS) was added on the basis of the internal structure to prepare walnut oil oleogel (SPI-PS-WOG). Ultrasonic treatment was applied to the mixed solution to make SPI-PS-WOG, on the basis, the effects of ultrasonic treatment on SPI-PS-WOG were investigated. The results showed that both ß and ß' crystalline forms were present in all SPI-PS-WOG samples. When the ultrasonic power was 450 W, the first weight loss peak in the thermogravimetric (TGA) curve appeared at 326 °C, which was shifted to the right compared to the peak that occurred when the ultrasonic power was 0 W, indicating that the thermal stability of the SPI-PS-WOG was improved by the ultrasonic treatment. Moreover, when the ultrasonic power was 450 W, the oil holding capacity (OHC) reached 95.3 %, which was the best compared with other groups. Both confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) showed that the ultrasonic treatment of appropriate power succeeded in making the SPI-PS-WOG samples more evenly dispersed in the internal structure and denser in the external structure. In terms of oxidative stability, it was found that the peroxide value of SPI-PS-WOG remained at 9.8 mmol/kg oil for 50 days under 450 W ultrasonic power treatment, which was significantly improved compared with liquid walnut oil (WO). These results provide a new idea for the preparation of oleogels, and also lay a theoretical foundation for the application of ultrasonic treatment in oleogels.


Assuntos
Fosfatidilserinas , Óleos de Plantas , Ultrassom , Juglans/química , Compostos Orgânicos/química , Compostos Orgânicos/efeitos da radiação , Oxirredução/efeitos da radiação , Fosfatidilserinas/química , Óleos de Plantas/química , Proteínas de Soja/química
14.
Ultrason Sonochem ; 82: 105871, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34915255

RESUMO

In this study, an emulsion stabilized by soy protein isolate (SPI)-pectin (PC) complexes was prepared to investigate the effects of high-intensity ultrasound (HIU) treatment (150-600 W) on the physicochemical properties, microstructure, and stability of emulsions. The results found that the emulsion treated at 450 W showed the best emulsion stability index (ESI) (25.18 ± 1.24 min), the lowest particle size (559.82 ± 3.17 nm), the largest ζ-potential absolute value (16.39 ± 0.18 mV), and the highest adsorbed protein content (27.31%). Confocal laser scanning microscopy (CLSM) and atomic force microscopy (AFM) revealed that the emulsion aggregation was significantly improved by ultrasound treatment, and the average roughness value (Rq) was the smallest (10.3 nm) at 450 W. Additionally, HIU treatment reduced the interfacial tension and apparent viscosity of the emulsion. Thermal stability was best when the emulsion was treated at 450 W, D43 was minimal (907.95 ± 31.72 nm), and emulsion separation also improved. Consequently, the creaming index (CI) was significantly decreased compared to the untreated sample, indicating that the storage stability of the emulsion was enhanced.


Assuntos
Ultrassom , Emulsões , Tamanho da Partícula , Pectinas , Proteínas de Soja , Glycine max , Viscosidade , Água
15.
Ultrason Sonochem ; 80: 105808, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34737159

RESUMO

In this study, a soy protein isolate (SPI)-pectin (PC) complex was prepared, and the effects of different high intensity ultrasound (HIU) powers on the structure and solubility of the complex were studied. Fourier transform infrared (FTIR) spectroscopy analysis exhibited that with increasing HIU power, the α-helix content of the SPI in the complex was significantly reduced, and the random coil content increased; however, an opposite trend appeared after higher power treatments. Fluorescence spectra showed that HIU treatment increased the fluorescence intensity of the complex, and the surface hydrophobicity was increased. The trend of the protein structure studied by Raman spectroscopy was similar to that of FTIR and fluorescence spectroscopy. When the HIU treatment was performed for 15 min and at 450 W power, the particle size of the complex was 451.85 ± 2.17 nm, and the solubility was 89.04 ± 0.19 %, indicating that the HIU treatment caused the spatial conformation of the protein to loosen and improved the functional properties of the complex. Confocal laser scanning microscopy (CLSM) revealed that the complex after HIU treatment exhibited improved dispersibility in water and smaller particle size. Gel electrophoresis results indicated that HIU treatment did not affect the protein subunits of the complex. Therefore, the selection of a suitable HIU treatment power can effectively improve the structural properties and solubility of SPI in the complex, and promote the application of the SPI-PC complex in food processing and industries.


Assuntos
Glycine max , Interações Hidrofóbicas e Hidrofílicas , Pectinas , Solubilidade , Proteínas de Soja , Ondas Ultrassônicas
16.
Ultrason Sonochem ; 79: 105756, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34562736

RESUMO

In this study, soybean protein isolate (SPI) and pectin emulsion gels were prepared by thermal induction, and the effects of high intensity ultrasound (HIU) at various powers (0, 150, 300, 450 and 600 W) on the structure, gel properties and stability of emulsion gels were investigated. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) showed that the interaction between SPI and pectin was enhanced and the crystallinity of the emulsion gels was changed due to the HIU treatment. Confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) observations revealed that the particle size of the emulsion gels was decreased significantly by HIU treatment. The emulsion gel structure became more uniform and denser, which was conducive to storage stability. In addition, according to the low field nuclear magnetic resonance (LF-NMR) analysis, HIU treatment had no obvious impact on the content of bound water as the power increased to 450 W, while the content of free water decreased gradually and became immobilized water, which indicated that the water holding capacity of the emulsion gels was enhanced. Compared with untreated emulsion gel, differential scanning calorimetry (DSC) analysis showed that the denaturation temperature reached 131.9 ℃ from 128.2 ℃ when treated at 450 W. The chemical stability and bioaccessibility of ß-carotene in the emulsion gels were improved significantly after HIU treatment during simulated in vitro digestion.


Assuntos
Pectinas , Proteínas de Soja , Ondas Ultrassônicas , beta Caroteno , Emulsões , Géis , Água
17.
J Oleo Sci ; 70(10): 1357-1366, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34497182

RESUMO

A homemade nanonickel catalyst was made by the ultrasonic liquid-phase reduction method, characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy, and applied to the isomerization reaction of high linoleic acid sunflower oil. Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and particle size analysis showed that the homemade nickel particles were spherical, uniformly dispersed, less agglomerated, 20 to 75 nm in size, and nanoscale nickel powder. Compared with commercially available Raney nickel, the homemade nanonickel powder has a larger specific surface area, smaller pore size and higher catalytic activity. The X-ray diffraction spectrum of the homemade nanonickel powder had distinct diffraction peaks at its characteristic peaks which indicated that the powder was pure nickel. The nanometal nickel particles are fully dispersed in high oleic sunflower oil under the action of ultrasound. The results showed that it could effectively reduce the activation reaction time of nanonickel, and the conversion rate of conjugated linoleic acid could reach 86.24%. The process of activating the catalyst is omitted, the number of times of repeated uses of the nanonickel catalyst is increased, and the environmental pollution of the production is avoided. To obtain sunflower oil rich in CLA, it also provides a new idea for the preparation of conjugated linoleic acid.


Assuntos
Ácidos Linoleicos Conjugados/química , Nanopartículas/química , Níquel/química , Óleo de Girassol/química , Ondas Ultrassônicas , Catálise , Fenômenos Químicos , Poluição Ambiental/prevenção & controle , Isomerismo , Tamanho da Partícula , Pós
18.
J Oleo Sci ; 70(9): 1231-1238, 2021 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-34373403

RESUMO

The solubility of hydrogen in n-hexane was determined using a homemade reactor. The solubility of hydrogen in soybean oil was established using the Peng-Robinson (PR) equation of state and the van der Waals mixing rule. The curve equation established a linear relationship between the solubility of hydrogen in oil and the number of moles of hydrogen in the reactor. Under the optimal temperature and catalyst, the relationship between the hydrogen consumption of the hydrogenation of oil and fat and the TFAs formed in the oil was determined. When the reaction pressure exceeded 3.0 MPa, the hydrogenation of oil was consumed. The amount of hydrogen, the rate of hydrogenation, and the change in the TFAs all stabilized. Therefore, the pressure of the general hydrogenation reaction should not exceed 3.0 MPa. This result provides a quick and simple method for controlling TFAs in oils and fats for industrial applications.


Assuntos
Hidrogênio/química , Óleo de Soja/química , Reatores Biológicos , Catálise , Hidrogenação , Extratos Vegetais , Temperatura , Ácidos Graxos trans/química
19.
Ultrason Sonochem ; 77: 105700, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34364068

RESUMO

In this study, microcapsules were prepared by spray drying and embedding hemp seed oil (HSO) with soy protein isolate (SPI) and maltodextrin (MD) as wall materials. The effect of ultrasonic power on the microstructure and characteristics of the composite emulsion and microcapsules was studied. Studies have shown that ultrasonic power has a significant impact on the stability of composite emulsions. The particle size of the composite emulsion after 450 W ultrasonic treatment was significantly lower than the particle size of the emulsion without the ultrasonic treatment. Through fluorescence microscopy observation, HSO was found to be successfully embedded in the wall materials to form an oil/water (O/W) composite emulsion. The spray-dried microcapsules showed a smooth spherical structure through scanning electron microscopy (SEM), and the particle size was 10.7 µm at 450 W. Fourier transform infrared (FTIR) spectroscopy analysis found that ultrasonic treatment would increase the degree of covalent bonding of the SPI-MD complex to a certain extent, thereby improving the stability and embedding effect of the microcapsules. Finally, oxidation kinetics models of HSO and HSO microcapsules were constructed and verified. The zero-order model of HSO microcapsules was found to have a higher degree of fit; after verification, the model can better reflect the quality changes of HSO microcapsules during storage.


Assuntos
Cannabis/química , Modelos Químicos , Extratos Vegetais/química , Polissacarídeos/química , Proteínas de Soja/química , Ondas Ultrassônicas , Cápsulas , Cinética , Oxirredução
20.
J Oleo Sci ; 69(10): 1191-1198, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-32908091

RESUMO

The kinetics of catalytic transfer hydrogenation (CTH) of low-erucic-acid rapeseed oil using ammonium formate as a hydrogen donor over a Ni-Ag0.15/SBA15 catalyst were studied. Then, a kinetic model for the hydrogenation of low-erucic-acid rapeseed oil was established, and it was found that the reaction rate constants of hydrogenations of 9c-18:1 and 12c-18:1 oleic acid were 0.1262 and 0.0148, and the catalytic selectivity of linoleic acid was 2.04. For the catalyst loading of 0.23%, the hydrogenation temperature was 80°C, the ammonium formate concentration was 0.32 mol/50 mL, and the low-erucic-acid rapeseed oil was hydrogenated in 90 min; it was also found that the iodine value of low-erucic-acid rapeseed oil was 80 g I2/100 g, the oleic acid content was 65%, and the trans fatty acids (TFAs) content was only 6.7%. Therefore, CTH may be widely used in the modification of oils and fats.


Assuntos
Ácidos Erúcicos , Cinética , Níquel/química , Óleo de Brassica napus/química , Prata/química , Catálise , Formiatos/química , Temperatura Alta , Hidrogenação , Iodo/análise , Ácido Linoleico/análise , Ácido Linoleico/química , Ácido Oleico/análise , Ácido Oleico/química , Ácidos Graxos trans/análise
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