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1.
Food Chem ; 332: 127381, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32603917

RESUMO

In this work, three different polyether-modified siloxanes (PMS1, PMS2, and PMS3) were applied to stabilize water-in-oil emulsions, and sodium caseinate (SC) was used to establish water-in-oil-in-water (W/O/W) emulsions. Here, PMS polymers were modified by Isolan GPS and SC by Tween 80. The impact of modifications on the physical stability and controlled release of W/O/W emulsions were investigated. It was found that the storage stability and control release of double emulsions were dependent on the types of PMS used, percent of Isolan GPS, and Tween 80. When PMS1 and PMS2 were combined with low percent of Isolan GPS and Tween 80, the dispersed droplet sizes were reduced, lower percent in the gravitational sedimentation were achieved than using PMS3 emulsions. The controlled releases of Mg2+ from W/O/W emulsions by using PMS3 were slower than using other PMS. PMS3 had a strong influence in controlling the release of Mg2+ from the double emulsions.


Assuntos
Emulsões/química , Siloxanas/química , Caseínas/química , Condutividade Elétrica , Magnésio/metabolismo , Óleos/química , Tamanho da Partícula , Polissorbatos/química , Tensão Superficial , Água/química
2.
Food Chem ; 333: 127448, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32663748

RESUMO

Antarctic krill oil (AKO) is an emerging dietary supplement containing metal ions that influence oil oxidation. Thus, this study focuses on the effect and mechanism of metal ions on phospholipid oxidation in AKO. Firstly, AKO containing Mg2+, Mn2+, Cu2+, Fe2+ and Fe3+ (200 µmol/kg) were prepared separately and incubated at 60 °C for 6 days. Peroxide value (POV) and malondialdehyde (MDA) content showed that Fe3+ exhibited the most effective prooxidative activity, with the prooxidative activity of Fe2(SO4)3 (water-soluble) being stronger than that of ferric oleate (FeOl, fat-soluble). In addition, phosphatidylethanolamine (PE) oxidation degree (more than 90%) was considerably greater than phosphatidylcholine (PC) oxidation degree (about 15%) in AKO. Differences in the structure of head group hindered chelation of PC with metal ions than PE due to electrostatic repulsion and steric hindrance. Therefore, PC significantly inhibited, while PE promoted, the oxidation of polyunsaturated triacylglycerol (TAG), like fish oil (p < 0.01).


Assuntos
Euphausiacea/química , Metais/química , Óleos/química , Fosfolipídeos/química , Animais , Regiões Antárticas , Cátions/química , Suplementos Nutricionais , Malondialdeído/química , Oxirredução , Fosfatidilcolinas/química , Fosfatidiletanolaminas/química , Triglicerídeos/química
3.
Food Chem ; 332: 127486, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32663756

RESUMO

Activated complex theory (ACT), apart from Van 't Hoff equation, has long been applying as an alternative tool to connect the kinetics (reaction rate constant, k) and thermodynamics parameters (including standard enthalpy of activation, △H++; standard entropy of activation, △S++; standard Gibbs free energy of activation, △G++). The study mainly focuses on ACT application in food systems, especially oil and fruit juice processing. Considering there are several improper calculations or mistakes often found in papers published recently in 2014-2019, three considerations are presented when applying the ACT, including 1) Understand that the reaction should be a single chemical elementary step; 2) Ensure that the units used should be consistent; 3) Effectively analyze the kinetics and thermodynamic parameters by choosing proper temperatures. This study is expected to further improve the understanding and correct application of this well-known theory in future work.


Assuntos
Manipulação de Alimentos/métodos , Tecnologia de Alimentos , Entropia , Tecnologia de Alimentos/métodos , Sucos de Frutas e Vegetais/análise , Cinética , Óleos/química , Temperatura , Termodinâmica
4.
PLoS One ; 15(7): e0236837, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32730369

RESUMO

Recent developments propose renewed use of surface-modified nanoparticles (NPs) for enhanced oil recovery (EOR) due to improved stability and reduced porous media retention. The enhanced surface properties render the nanoparticles more suitable compared to bare nanoparticles, for increasing the displacement efficiency of waterflooding. However, the EOR mechanisms using NPs are still not well established. This work investigates the effect of in-situ surface-modified silica nanoparticles (SiO2 NPs) on interfacial tension (IFT) and wettability behavior as a prevailing oil recovery mechanism. For this purpose, the nanoparticles have been synthesized via a one-step sol-gel method using surface-modification agents, including Triton X-100 (non-ionic surfactant) and polyethylene glycol (polymer), and characterized using various techniques. These results exhibit the well-defined spherical particles, particularly in the presence of Triton X-100 (TX-100), with particle diameter between 13 to 27 nm. To this end, SiO2 nanofluids were formed by dispersing nanoparticles (0.05 wt.%, 0.075 wt.%, 0.1 wt.%, and 0.2 wt.%) in 3 wt.% NaCl to study the impact of surface functionalization on the stability of the nanoparticle suspension. The optimal stability conditions were obtained at 0.1 wt.% SiO2 NPs at a basic pH of 10 and 9.5 for TX-100/ SiO2 and PEG/SiO nanofluids, respectively. Finally, the surface-treated SiO2 nanoparticles were found to change the wettability of treated (oil-wet) surface into water-wet by altering the contact angle from 130° to 78° (in case of TX-100/SiO2) measured against glass surface representing carbonate reservoir rock. IFT results also reveal that the surfactant treatment greatly reduced the oil-water IFT by 30%, compared to other applied NPs. These experimental results suggest that the use of surface-modified SiO2 nanoparticles could facilitate the displacement efficiency by reducing IFT and altering the wettability of carbonate reservoir towards water-wet, which is attributed to more homogeneity and better dispersion of surface-treated silica NPs compared to bare-silica NPs.


Assuntos
Nanopartículas/química , Óleos/isolamento & purificação , Dióxido de Silício/química , Tensoativos/química , Óleos/análise , Óleos/química , Tensão Superficial , Molhabilidade
5.
PLoS One ; 15(6): e0234176, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32497151

RESUMO

Chronic neuropathic pain (NP) is a growing clinical problem for which effective treatments, aside from non-steroidal anti-inflammatory drugs and opioids, are lacking. Cannabinoids are emerging as potentially promising agents to manage neuroimmune effects associated with nociception. In particular, Δ9-tetrahydrocannabinol (THC), cannabidiol (CBD), and their combination are being considered as therapeutic alternatives for treatment of NP. This study aimed to examine whether sex affects long-term outcomes on persistent mechanical hypersensitivity 7 weeks after ceasing cannabinoid administration. Clinically relevant low doses of THC, CBD, and a 1:1 combination of THC:CBD extracts, in medium chain triglyceride (MCT) oil, were orally gavaged for 14 consecutive days to age-matched groups of male and female sexually mature Sprague Dawley rats. Treatments commenced one day after surgically inducing a pro-nociceptive state using a peripheral sciatic nerve cuff. The analgesic efficacy of each phytocannabinoid was assessed relative to MCT oil using hind paw mechanical behavioural testing once a week for 9 weeks. In vivo intracellular electrophysiology was recorded at endpoint to characterize soma threshold changes in primary afferent sensory neurons within dorsal root ganglia (DRG) innervated by the affected sciatic nerve. The thymus, spleen, and DRG were collected post-sacrifice and analyzed for long-term effects on markers associated with T lymphocytes at the RNA level using qPCR. Administration of cannabinoids, particularly the 1:1 combination of THC, elicited a sustained mechanical anti-hypersensitive effect in males with persistent peripheral NP, which corresponded to beneficial changes in myelinated Aß mechanoreceptive fibers. Specific immune cell markers associated with T cell differentiation and pro-inflammatory cytokines, previously implicated in repair processes, were differentially up-regulated by cannabinoids in males treated with cannabinoids, but not in females, warranting further investigation into sexual dimorphisms that may underlie treatment outcomes.


Assuntos
Analgésicos/administração & dosagem , Analgésicos/farmacologia , Canabidiol/efeitos adversos , Canabidiol/farmacologia , Dronabinol/administração & dosagem , Dronabinol/farmacologia , Óleos/química , Administração Oral , Analgésicos/química , Animais , Biomarcadores/metabolismo , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Canabidiol/química , Dronabinol/química , Composição de Medicamentos , Interações Medicamentosas , Feminino , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley
6.
Food Chem ; 329: 127219, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32516714

RESUMO

Plant-based proteins and polyphenols are increasingly being explored as functional food ingredients. Colloidal complexes were prepared from pea protein (PP) and grape seed proanthocyanidin (GSP) and the ability of the PP/GSP complexes to form and stabilize oil-in-water emulsions were investigated. The main interactions between PP and GSP were hydrogen bonding. The stability of PP-GSP complexes to environmental changes were studied: pH (2-9); ion strength (0-0.3 M); and temperature (30-90 °C). Emulsions produced using PP-GSP complexes as emulsifiers had small mean droplet diameters (~200 nm) and strongly negative surface potentials (~-60 mV). Compared to PP alone, PP-GSP complexes slightly decreased the isoelectric point, thermostability, and salt stability of the emulsions, but increased their storage stability. The presence of GSP gave the emulsions a strong salmon (red-yellow) color, which may be beneficial for some specific applications. These results may assist in the creation of more efficacious food-based strategies for delivering proanthocyanidins.


Assuntos
Emulsões/química , Extrato de Sementes de Uva/química , Proteínas de Ervilha/química , Ervilhas/metabolismo , Polifenóis/química , Proantocianidinas/química , Antioxidantes/química , Sítios de Ligação , Calorimetria , Extrato de Sementes de Uva/metabolismo , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Simulação de Acoplamento Molecular , Óleos/química , Concentração Osmolar , Proteínas de Ervilha/metabolismo , Polifenóis/metabolismo , Proantocianidinas/metabolismo , Cloreto de Sódio/química , Temperatura , Água/química
7.
Food Chem ; 324: 126894, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32361094

RESUMO

This study aims to extract acorn protein isolate (API) from locally abundant waste acorn fruit and investigate its emulsification behavior by mixing different protein (0.1-2% w/v) and oil volume concentrations (5-45% v/v). Significant decrease in emulsifying activity index (EAI) and an increase in emulsifying stability index (ESI) were observed with an increase in API concentrations (P < 0.05). Droplet sizes of emulsions and viscosity were observed to decrease significantly (P < 0.05) with increase in API concentration while the increase was observed in interfacial protein concentration (Г). In contrast, increase in oil volume concentration results in increase of droplet sizes, packing fractions and viscosity, while decrease in Г values was observed. The results reveal that main fractions of API (66.2-14.4 kDa) were migrated to oil-water interface for emulsion stabilization. These results demonstrate the potential application of API in food formulation and development.


Assuntos
Emulsificantes/química , Óleos/química , Proteínas de Plantas/química , Quercus/metabolismo , Eletroforese em Gel de Poliacrilamida , Emulsões/química , Frutas/metabolismo , Viscosidade
8.
Food Chem ; 327: 127039, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32454273

RESUMO

In this study, we investigated the tailoring of food emulsions using interactions between rice bran cellulose nanocrystals (CNCs) and lauric arginate (LAE), which is food-grade cationic surfactant. Complexes of anionic CNCs and cationic LAE (CNCs/LAE) were formed through electrostatic attraction which were characterized using isothermal titration calorimetry (ITC), turbidity, and zeta-potential measurements. The saturation complexes could be formed at ratios of 1:2 (w/w) CNCs-to-LAE. Furthermore, the physical and oxidative stability of oil-in-water emulsions containing lipid droplets coated by CNCs/LAE complexes was determined. Electrostatic complexes formed from 0.02% CNCs and 0.1% LAE produced stable Pickering emulsions that were resistant to droplet coalescence. It was also exhibited that 0.02% CNCs and 0.1% LAE complexes stabilized-emulsions was able to extend the lag phase to 20 days for lipid hydroperoxide and to 14 days for hexanal production. This study shows that food-grade Pickering emulsions with good stability can be produced by CNCs with LAE complexes.


Assuntos
Arginina/análogos & derivados , Celulose/química , Alimentos , Nanopartículas/química , Óleos/química , Tensoativos/química , Água/química , Arginina/química , Emulsões , Eletricidade Estática
9.
Int J Nanomedicine ; 15: 2071-2083, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32273703

RESUMO

Background and Purpose: Adjuvant can reduce vaccine dosage and acquire better immune protection to the body, which helps to deal with the frequent outbreaks of influenza. Nanoemulsion adjuvants have been proved efficient, but the relationship between their key properties and the controlled release which greatly affects immune response is still unclear. The present work explores the role of factors such as particle size, the polydispersity index (PDI), stability and the safety of nanoemulsions by optimizing the water concentration, oil phase and modes of carrying, to explain the impact of those key factors above on adjuvant effect. Methods: Isopropyl myristate (IPM), white oil, soybean oil, and grape-kernel oil were chosen as the oil phase to explore their roles in emulsion characteristics and the adjuvant effect. ICR mice were immunized with an emulsion-inactivated H3N2 split influenza vaccine mixture, to compare the nanoemulsion's adjuvant with traditional aluminium hydroxide or complete Freund's adjuvant. Results: Particle size of all the nanoemulsion formed in our experiment ranged from 20 nm to 200 nm and did not change much when diluted with water, while the PDI decreased obviously, indicating that the particles tended to become more dispersive. Formulas with 80% or 85.6% water concentration showed significant higher HAI titer than aluminium hydroxide or complete Freund's adjuvant, and adsorption rather than capsule mode showed higher antigen delivery efficiency. As mentioned about oil phase, G (IPM), F (white oil), H (soybean oil), and I (grape-kernel oil) showed a decreasing trend in their adjuvant efficiency, and nanoemulsion G was the best adjuvant with smaller and uniform particle size. Conclusion: Emulsions with a smaller, uniform particle size had a better adjuvant effect, and the adsorption mode was generally more efficient than the capsule mode. The potential adjuvant order of the different oils was as follows: IPM > white oil > soybean oil > grape-kernel oil.


Assuntos
Adjuvantes Imunológicos/química , Sistemas de Liberação de Medicamentos/métodos , Emulsões/química , Vacinas contra Influenza/administração & dosagem , Nanoestruturas/química , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/farmacologia , Animais , Emulsões/administração & dosagem , Emulsões/farmacologia , Feminino , Vírus da Influenza A Subtipo H3N2 , Vacinas contra Influenza/imunologia , Camundongos Endogâmicos ICR , Óleos/química , Infecções por Orthomyxoviridae/prevenção & controle , Tamanho da Partícula , Óleo de Soja/química , Vacinas de Produtos Inativados , Água/química
10.
J Vis Exp ; (157)2020 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-32281972

RESUMO

Restriction endonuclease (REase) specificity engineering is extremely difficult. Here we describe a multistep protocol that helps to produce REase variants that have more stringent specificity than the parental enzyme. The protocol requires the creation of a library of expression selection cassettes (ESCs) for variants of the REase, ideally with variability in positions likely to affect DNA binding. The ESC is flanked on one side by a sequence for the restriction site activity desired and a biotin tag and on the other side by a restriction site for the undesired activity and a primer annealing site. The ESCs are transcribed and translated in a water-in-oil emulsion, in conditions that make the presence of more than one DNA molecule per droplet unlikely. Therefore, the DNA in each cassette molecule is subjected only to the activity of the translated, encoded enzyme. REase variants of the desired specificity remove the biotin tag but not the primer annealing site. After breaking the emulsion, the DNA molecules are subjected to a biotin pulldown, and only those in the supernatant are retained. This step assures that only ESCs for variants that have not lost the desired activity are retained. These DNA molecules are then subjected to a first PCR reaction. Cleavage in the undesired sequence cuts off the primer binding site for one of the primers. Therefore, PCR amplifies only ESCs from droplets without the undesired activity. A second PCR reaction is then carried out to reintroduce the restriction site for the desired specificity and the biotin tag, so that the selection step can be reiterated. Selected open reading frames can be overexpressed in bacterial cells that also express the cognate methyltransferase of the parental REase, because the newly evolved REase targets only a subset of the methyltransferase target sites.


Assuntos
Enzimas de Restrição do DNA/metabolismo , Evolução Molecular Direcionada , Sequência de Aminoácidos , Sequência de Bases , Primers do DNA/metabolismo , Enzimas de Restrição do DNA/química , Emulsões/química , Expressão Gênica , Mutagênese/genética , Óleos/química , Biossíntese de Proteínas , Engenharia de Proteínas , Especificidade por Substrato , Transcrição Genética , Água/química
11.
Chemosphere ; 251: 126348, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32146185

RESUMO

Due to the variety of oily wastewater and complexity of separation system, it has put forward new challenge and requirement to separation materials for on-demand separation of various oil/water mixtures. Here, we reported a facile waste-to-resource strategy to rationally fabricate hierarchical ZnO nanopillars coating onto the surface of waste brick grains (ZnO/WBG) via simple physical process and in-situ growth technique. Specifically, the directly as-prepared ZnO/WBG possess superhydrophilic/underwater superoleophobic (UWSOB) properties and modified ZnO/WBG by organosilicon reagent possess quasi superhydrophobic/superoleophilic (SHOBI) properties. It is also worth noting that this discrete ZnO/WBG with opposite wettability can be accumulated into ZnO/WBG layer with numerous tortuous channel structure, making it feasible for on-demand separating various oil/water mixtures whether immiscible light- and heavy-oil/water mixtures or oil-in-water and water-in-oil emulsions. It has been demonstrated that the filter layers with opposite wettability exhibit high separation efficiency and flux, excellent chemical stability and admirable recyclability. Thus, this novel and cost-effective ZnO/WBG layer holds great promise for large-scale and versatile oil/water separation. Additionally, this work presents a sustainable perspective of effectively utilizing waste brick to construct workable functionalized materials with tremendous application potential, showing far-reaching value and significance in fundamental research and environmental protection.


Assuntos
Purificação da Água/métodos , Emulsões , Interações Hidrofóbicas e Hidrofílicas , Óleos/química , Águas Residuárias , Água/química , Molhabilidade
12.
Electron. j. biotechnol ; 44: 60-68, Mar. 2020. tab, graf, ilus
Artigo em Inglês | LILACS | ID: biblio-1087705

RESUMO

Background: Oleaginous yeasts can be grown on different carbon sources, including lignocellulosic hydrolysate containing a mixture of glucose and xylose. However, not all yeast strains can utilize both the sugars for lipogenesis. Therefore, in this study, efforts were made to isolate dual sugar-utilizing oleaginous yeasts from different sources. Results: A total of eleven isolates were obtained, which were screened for their ability to utilize various carbohydrates for lipogenesis. One promising yeast isolate Trichosporon mycotoxinivorans S2 was selected based on its capability to use a mixture of glucose and xylose and produce 44.86 ± 4.03% lipids, as well as its tolerance to fermentation inhibitors. In order to identify an inexpensive source of sugars, nondetoxified paddy straw hydrolysate (saccharified with cellulase), supplemented with 0.05% yeast extract, 0.18% peptone, and 0.04% MgSO4 was used for growth of the yeast, resulting in a yield of 5.17 g L−1 lipids with conversion productivity of 0.06 g L−1 h−1 . Optimization of the levels of yeast extract, peptone, and MgSO4 for maximizing lipid production using Box­Behnken design led to an increase in lipid yield by 41.59%. FAME analysis of single cell oil revealed oleic acid (30.84%), palmitic acid (18.28%), and stearic acid (17.64%) as the major fatty acids. Conclusion: The fatty acid profile illustrates the potential of T. mycotoxinivorans S2 to produce single cell oil as a feedstock for biodiesel. Therefore, the present study also indicated the potential of selected yeast to develop a zero-waste process for the complete valorization of paddy straw hydrolysate without detoxification


Assuntos
Trichosporon/metabolismo , Oryza , Xilose/isolamento & purificação , Trichosporon/química , Óleos/química , Lipogênese , Biocombustíveis , Fermentação , Glucose/isolamento & purificação , Hidrólise , Lignina/metabolismo , Lipídeos/biossíntese
13.
Food Chem ; 320: 126653, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32217430

RESUMO

Curcumin is claimed to have many health benefits, but it has low chemical stability. In this study, the influence of food-grade antioxidants on the chemical degradation of curcumin-enriched oil-in-water emulsions was examined. The curcumin degradation rate and extent depended on antioxidant type. The water-soluble antioxidants were more effective at protecting curcumin from degradation than the oil-soluble ones, which may have been because curcumin degrades faster in water than in oil. Interestingly, the amphiphilic antioxidant was almost as effective as the water-soluble ones. The oil-soluble antioxidant actually slightly promoted curcumin degradation. In summary, curcumin retention after storage declined in the following order: 82.6% (Trolox) ~82.2% (ascorbic acid) >79.5% (ascorbyl palmitate) ≫57.9% (control) >52.7% (α-tocopherol). The effectiveness of ascorbic acid in stabilizing curcumin increased as its concentration was raised (0-300 µM). Our results may facilitate the creation of curcumin-enriched foods and beverages with enhanced bioactivity.


Assuntos
Antioxidantes/química , Curcumina/química , Emulsões/química , Ácido Ascórbico/análogos & derivados , Ácido Ascórbico/química , Cromanos/química , Óleos/química , Solubilidade , Água/química , alfa-Tocoferol/química
14.
J Chromatogr A ; 1620: 460989, 2020 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32151414

RESUMO

A GC-MS based analytical method was developed for the profiling of oil-based AAS products using 15 organic constituents as target compounds. A total of 219 compounds were identified in 109 seized AAS products, among them 15 target compounds were selected. The selection was based on each compound's occurrence, reproducibility, and variance between products. The 15 target compounds did not include the active steroid itself, but only compounds found in the carrier oil. The subsequent method validation included assessment of specificity, linearity, precision, robustness and sample stability. The method was finally applied for the classification of a set of 27 seizures of AAS products supplied by the police. The classification was based on the Pearson correlation coefficient using pre-treated peak area data from the 15 target compounds. A successful classification was obtained, with only a small overlap between linked and unlinked samples. A 1% false-positive rate could be obtained at a threshold of 0.625 in terms of the Pearson distance. The present study thus demonstrates that it is possible to profile and classify AAS products with regard to a common origin. As the profiling method is not specific with regards to the steroid content, it may potentially be used to profile and compare other kinds of oil-based liquids.


Assuntos
Anabolizantes/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Óleos/química , Esteroides/análise , Anabolizantes/química , Humanos , Reprodutibilidade dos Testes , Esteroides/química
15.
Nat Commun ; 11(1): 315, 2020 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-31949137

RESUMO

Standard inactivated influenza vaccines are poorly immunogenic in immunologically naive healthy young children, who are particularly vulnerable to complications from influenza. For them, there is an unmet need for better influenza vaccines. Oil-in-water emulsion-adjuvanted influenza vaccines are promising candidates, but clinical trials yielded inconsistent results. Here, we meta-analyze randomized controlled trials with efficacy data (3 trials, n = 15,310) and immunogenicity data (17 trials, n = 9062). Compared with non-adjuvanted counterparts, adjuvanted influenza vaccines provide a significantly better protection (weighted estimate for risk ratio of RT-PCR-confirmed influenza: 0.26) and are significantly more immunogenic (weighted estimates for seroprotection rate ratio: 4.6 to 7.9) in healthy immunologically naive young children. Nevertheless, in immunologically non-naive children, adjuvanted and non-adjuvanted vaccines provide similar protection and are similarly immunogenic. These results indicate that oil-in-water emulsion adjuvant improves the efficacy of inactivated influenza vaccines in healthy young children at the first-time seasonal influenza vaccination.


Assuntos
Adjuvantes Imunológicos/química , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Óleos/química , Água/química , Anticorpos Antivirais/sangue , Formação de Anticorpos , Criança , Bases de Dados Factuais , Emulsões , Humanos , Imunidade , Vacinas contra Influenza/sangue , Vacinas contra Influenza/química , Influenza Humana/imunologia , Orthomyxoviridae , Vacinação
16.
Food Chem ; 313: 126139, 2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31927203

RESUMO

Based on various antioxidant mechanisms, four kinds of antioxidants including ascorbyl palmitate (AP), vitamin E (VE), phytic acid (PA) and one of the polyphenols (antioxidant of bamboo leaves, tea polyphenol palmitate or tea polyphenols (TP)) were used in combination to improve oxidative stability of docosahexaenoic acid (DHA) algae oil. To achieve the best effect, the formulations and mixture ratios of the antioxidant combinations were optimized. The effects were monitored by peroxide value, thiobarbituric acid-reactive substances, acid value, free radicals, Rancimat induction time and fatty acid composition of DHA algae oil undergoing accelerated storage. Finally, the DHA algae oil containing 80 mg/kg AP, 80 mg/kg VE, 40 mg/kg PA and 80 mg/kg TP had the highest oxidative stability. Furthermore, the shelf life of DHA algae oil containing the optimum composite antioxidant was predicted by using accelerated shelf life testing coupled with Arrhenius model, which was 3.80-fold longer than the control sample.


Assuntos
Antioxidantes/química , Ácidos Docosa-Hexaenoicos/química , Óleos/química , Ácido Ascórbico/análogos & derivados , Ácido Ascórbico/química , Armazenamento de Alimentos , Oxirredução , Folhas de Planta/química , Polifenóis/química , Sasa/química , Chá/química , Substâncias Reativas com Ácido Tiobarbitúrico/química , Vitamina E/química
17.
J Agric Food Chem ; 68(5): 1457-1467, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31931568

RESUMO

Antarctic krill oil (AKO) is susceptible to oxidation due to the high unsaturation degree of bioactive substances. Herein, a lipidomics method for in situ monitoring of the dynamic oxidation characteristics in AKO was explored based on electric soldering iron ion source (ESII) coupling with rapid evaporative ionization mass spectrometry (REIMS). The lipidomics profiles of AKO at different storage periods were successfully acquired. On the basis of principal component analysis and orthogonal partial least-squares analysis, the obtained REIMS data were employed to build a multivariate recognition model. The ions of m/z 707.50, 721.50, 833.49, and 837.54 contributed the most significant effect on the multivariate data model for the authentication of different AKO samples. Besides, the variation of viscosity, astaxanthin, and volatile compounds were also evaluated to corroborate the oxidation characteristics. The results indicated that the ESII-REIMS technology could be applied as an advanced rapid detection method to secure oil and fat quality during storage.


Assuntos
Euphausiacea/química , Lipidômica/métodos , Espectrometria de Massas/métodos , Óleos/química , Animais , Armazenamento de Alimentos , Oxirredução , Controle de Qualidade
18.
Food Chem ; 312: 126041, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31901829

RESUMO

Effect of fried food, oil type, moisture, fatty acid and molecular distribution on the effectiveness of rapid test of Total Polar Compounds (TPC) in frying oil based on dielectric constant was explored. Effects of all factors were compared and found to be significant (P < 0.05). Throughout the life cycle of frying oil, its rapid results were correlated well with those of conventional chromatography (Y = 0.7625X + 3.681, R2 = 0.8734). But the discrepancy was found within selected TPC ranges of 0%-10% and 20%-30%. According to the definition of TPC, three potential reasons for the high TPC values of fresh oils were discussed. For the deteriorated oils, the triglyceride dimers, mono-unsaturated and di-unsaturated fatty acids were found to be the main compositional factors by stepwise multivariate regression analysis. Pieces of advice about the operation guideline, internal control indices, calibration, reference oil, sensor, and detection range were proposed for instrument users and producers.


Assuntos
Óleos/química , Culinária , Ácidos Graxos/análise , Alimentos , Restaurantes , Fatores de Tempo , Triglicerídeos/análise
19.
Artigo em Inglês | MEDLINE | ID: mdl-31963838

RESUMO

The hydrophobicity and anti-fouling properties of materials have important application value in industrial and agricultural production and people's daily life. To study the relationship between the unit width L0 of the parabolic hydrophobic material and the hydrophobicity and anti-fouling properties, the rough surface structure of the parabolic with different widths was prepared by grinding with different SiC sandpapers, and further, to obtain hydrophobic materials through chemical oxidation and chemical etching, and modification with stearic acid (SA). The morphology, surface wetting and anti-fouling properties of the modified materials were characterized by SEM and contact angle measurement. The oil-water separation performance and self-cleaning performance of the materials were explored. The surface of the modified copper sheet forms a rough structure similar to a paraboloid. When ground with 1500 grit SiC sandpaper, it is more conducive to increase the hydrophobicity of the copper sheet surface and increase the contact angle of water droplets on the copper surface. Additionally, the self-cleaning and anti-fouling experiments showed that as L0 decreases, copper sheets were less able to stick to foreign things such as soil, and the better the self-cleaning and anti-fouling performance was. Based on the oil-water separation experiment of copper mesh, the lower L0 has a higher oil-water separation efficiency. The results showed that material with parabolic morphology has great self-cleaning, anti-fouling, and oil-water separation performance. The smaller the L0 was, the larger the contact angle and the better hydrophobic performance and self-cleaning performance were.


Assuntos
Cobre/química , Interações Hidrofóbicas e Hidrofílicas , Teste de Materiais , Óleos/química , Oxirredução , Ácidos Esteáricos/química , Água/química , Molhabilidade
20.
Soft Matter ; 16(5): 1359-1365, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-31934708

RESUMO

We confine a dense suspension of motile Escherichia coli inside a spherical droplet in a water-in-oil emulsion, creating a "bacterially" propelled droplet. We show that droplets move in a persistent random walk, with a persistence time τ∼ 0.3 s, a long-time diffusion coefficient D∼ 0.5 µm2 s-1, and an average instantaneous speed V∼ 1.5 µm s-1 when the bacterial suspension is at the maximum studied concentration. Several droplets are analyzed, varying the drop radius and bacterial concentration. We show that the persistence time, diffusion coefficient and average speed increase with the bacterial concentration inside the drop, but are largely independent of the droplet size. By measuring the turbulent-like motion of the bacteria inside the drop, we demonstrate that the mean velocity of the bacteria near the bottom of the drop, which is separated from a glass substrate by a thin lubrication oil film, is antiparallel to the instantaneous velocity of the drop. This suggests that the driving mechanism is a slippery rolling of the drop over the substrate, caused by the collective motion of the bacteria. Our results show that microscopic organisms can transfer useful mechanical energy to their confining environment, opening the way to the assembly of mesoscopic motors composed of microswimmers.


Assuntos
Escherichia coli/química , Óleos/química , Fenômenos Biomecânicos , Emulsões/química , Escherichia coli/citologia , Propriedades de Superfície , Tensoativos/química , Água/química
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