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1.
Water Res ; 170: 115324, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31770649

RESUMO

Aeration and mechanical agitation are the main drivers of aerosol generation in wastewater treatment plants (WWTPs). However, the effect of aeration mode on aerosol characteristics remains poorly understood. In this study, horizontal rotor aeration and fine bubble aeration in the same WWTP were selected to identify the effect on the emission, size distribution, microbial and chemical composition. For bacteria, fungi, Enterobacteriaceae, Staphylococcus aureus, and Pseudomonas aeruginosa in aerosols, the horizontal rotor aeration had higher contributions to the emissions than the fine bubble aeration. Horizontal rotor aeration generated a more coarse fraction (size > 7 µm) and a comparable respirable fraction (RF; size < 3.3 µm) compared with those of fine bubble aeration. More types of potential pathogens were generated by horizontal rotor aeration. The most easily aerosolized genera generated by horizontal rotor aeration and fine bubble aeration, were Trichosporon and Mycobacterium, with the aerosolization factors of 633.70 and 192.56, respectively. For Cl-, SO42-, NO3-, Zn, Ba, Cd, Sc, V, Rb, Ca, K, Ca, K, Mg, Na and Si in the aerosols, the contributions of fine bubble aeration were higher than those of horizontal rotor aeration. Due to the aerosol specialty from the different aeration modes, targeted manipulations should be employed to reduce the exposure risks.


Assuntos
Poluentes Atmosféricos , Águas Residuárias , Aerossóis , Bactérias , Monitoramento Ambiental , Fungos , Tamanho da Partícula
2.
J Photochem Photobiol B ; 202: 111666, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31837585

RESUMO

In this study, the effect of Polyp-Au-GO nanocomposite on VSMC proliferation, cell cycle proteins, down-regulation of mRNA in the rat was tested. Briefly, Polyp-Au-GO composite material was synthesized and characterized by UV-Vis spectra, X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM). Polyp-Au-GO composite exhibited the absorbance peak at 530 nm. XRD analysis confirmed the crystalline particle with size ranging between 16.5 and 32.6 nm. The crystallinity differences of the nanocomposite were examined by Raman spectroscopy analysis. The presence of a strong band (1500 cm-1) and the absence of other lower frequency bands confirmed that the absence of crystallinity of Polyp-Au-GO nanocomposite. The thermal properties of Polyp-Au-GO nanocomposite were determined by TGA analysis. The results revealed that 15% of its weight loss has occurred at 300 °C. Further, the growth of VSMCs was inhibited by the treatment of Polyp-Au-GO composite at 72 h. The IC50 value was registered at 0.57 µg/mL. Additionally, the Polyp-Au-GO composite arrest G1 cell cycle and down-regulated cell cycle proteins. These Polyp-Au-GO composite also reduced the extracellular ERK1/2 phosphorylation. Furthermore, Polyp-Au-GO composite inhibited TNF-R-evoked inflammatory responses. Moreover, Polyp-Au-GO composite inhibited of CEC proliferation. These results suggest that Polyp-Au-GO composite inhibits VSMC proliferation and TNF-R-mediated inflammatory responses. This study suggested the therapeutic role of Polyp-Au-GO composite in cardiovascular disease.


Assuntos
Grafite/química , Nanocompostos/química , Polifenóis/química , Animais , Aorta/efeitos dos fármacos , Aorta/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Regulação para Baixo/efeitos dos fármacos , Feminino , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Nanocompostos/toxicidade , Tamanho da Partícula , Fosforilação/efeitos dos fármacos , Polifenóis/farmacologia , Ratos
3.
J Sci Food Agric ; 100(1): 287-294, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31525263

RESUMO

BACKGROUND: Diacylglycerol (DAG) reduces body weight, suppresses body fat accumulation, and lowers the blood lipid concentration, and docosahexaenoic acid (DHA) can reduce the risk of occurrence of coronary artery diseases. RESULTS: DAG-rich algae oil with a high DHA content (55.9%) was synthesized via the lipase-catalyzed glycerolysis of algae oil, which consisted of triacylglycerol (43.9 mol%), DAG (40.9 mol%), and monoacylglycerol (15.2 mol%). The DAG-rich algae oil-in-water emulsions were prepared using three emulsifiers [whey protein concentrate (WPC), Tween80, and Tween80 + Span80]. The WPC-emulsion formed a thicker serum layer (6.67% at day 51) and larger oil droplets (d32 , 0.37 µm at day 28) than the Tween80- and Tween80 + Span80-emulsions (3.33-4.17%; 0.26 µm), and an upper cream layer with excess oil droplets was observed in only the WPC-emulsion, indicating that WPC-emulsion possesses the lowest emulsification stability. The hydroperoxide value and reduction rate of the DHA content were higher in the WPC-emulsions than in the Tween80- and Tween80 + Span80-emulsions during storage, which suggested that the WPC-emulsion had the lowest oxidation stability. CONCLUSION: The DAG-rich algae oil-in-water emulsion prepared with suitable emulsifiers, such as non-ionic emulsifiers, would have excellent emulsification and oxidative stabilities and provides a health benefit for special purposes in the food processing industry. © 2019 Society of Chemical Industry.


Assuntos
Diglicerídeos/química , Óleos Vegetais/química , Biocatálise , Emulsificantes/química , Emulsões/química , Lipase/química , Oxirredução , Tamanho da Partícula , Polissorbatos/química , Água/análise , Proteínas do Soro do Leite/química
4.
J Sci Food Agric ; 100(2): 695-704, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31602647

RESUMO

BACKGROUND: Long chain omega-3 polyunsaturated fatty acid (LCn3PUFA) nanoemulsion enriched foods offer the potential to address habitually low oily fish intakes. Nanoemulsions increase LCn3PUFA bioavailability, although they may cause lipid oxidation. The present study examined the oxidative stability of LCn3PUFA algal oil-in-water nanoemulsions created by ultrasound using natural and synthetic emulsifiers during 5 weeks of storage at 4, 20 and 40 °C. Fatty acid composition, droplet size ranges and volatile compounds were analysed. RESULTS: No significant differences were found for fatty acid composition at various temperatures and storage times. Lecithin nanoemulsions had significantly larger droplet size ranges at baseline and during storage, regardless of temperatures. Although combined Tween 40 and lecithin nanoemulsions had low initial droplet size ranges, there were significant increases at 40 °C after 5 weeks of storage. Gas chromatograms identified hexanal and propanal as predominant volatile compounds, along with 2-ethylfuran, propan-3-ol and valeraldehyde. The Tween 40 only nanoemulsion sample showed the formation of lower concentrations of volatiles compared to lecithin samples. The formation of hexanal and propanal remained stable at lower temperatures, although higher concentrations were found in nanoemulsions than in bulk oil. The lecithin only sample had formation of higher concentrations of volatiles at increased temperatures, despite having significantly larger droplet size ranges than the other samples. CONCLUSION: Propanal and hexanal were the most prevalent of five volatile compounds detected in bulk oil and lecithin and/or Tween 40 nanoemulsions. Oxidation compounds remained more stable at lower temperatures, indicating suitability for the enrichment of refrigerated foods. Further research aiming to evaluate the oxidation stability of these systems within food matrices is warranted. © 2019 Society of Chemical Industry.


Assuntos
Ácidos Graxos Ômega-3/química , Alimento Funcional/análise , Óleos Vegetais/química , Emulsificantes/química , Emulsões/química , Alimentos Fortificados/análise , Lecitinas/química , Oxirredução , Tamanho da Partícula , Temperatura Ambiente , Vegetarianos
5.
J Sci Food Agric ; 100(2): 764-774, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31605372

RESUMO

BACKGROUND: Air classification was used to fractionate canola meal (CM). The effect of combinations of air classification conditions, including rotor speed ranging from 300 to 1200 rpm, air stream rate from 700 to 860 cfpm, and secondary air from 0 to 30%, on particle size and nutritive composition was investigated. Response surface methodology was used to develop response surface equations to estimate these effects. RESULTS: Protein concentration increased in almost all the fine fractions. Effects of both secondary air and rotor speed of the air classifier were significant at P ≤ 0.1 and P ≤ 0.01, respectively. Almost all the fine fractions contained more oil. Rotor speed, air stream rate, and their interaction were significant at P ≤ 0.01. Both acid detergent fiber (ADF) and neutral detergent fiber (NDF) were shifted to the coarse fractions during the air classification. The rotor speed was significant for both ADF and NDF at P ≤ 0.01. CONCLUSIONS: Protein shifted to the fine fractions. The highest protein concentration in the fine CM fraction was estimated to be 404.2 g kg-1 , demonstrating an enhancement of 10.7%. ADF and NDF shifted to the coarse CM fractions and were respectively estimated to be 294.8 and 332 g kg-1 , which were increased by 52.7% and 43.7%. Oil shifted to the fine fractions. The highest concentration was predicted to be 59.7 g kg-1 , increased by 45.6%. Fine or coarse fraction yields were estimated to be 35-50%, indicating that they are acceptable for an industrial manufacture. © 2019 Society of Chemical Industry.


Assuntos
Brassica napus/química , Gorduras/análise , Manipulação de Alimentos/métodos , Fibras na Dieta/análise , Manipulação de Alimentos/instrumentação , Valor Nutritivo , Tamanho da Partícula
6.
Food Chem ; 305: 125436, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514047

RESUMO

The physicochemical properties of wheat bran have an effect on its technofunctional and nutritional profile. The possibility to induce physicochemical modifications in wheat bran using microfluidisation was investigated. An I-optimal experimental design was used to investigate the effect of microfluidisation processing parameters (pressure, number of passes, bran concentration and initial particle size) on important properties of wheat bran (particle size, microstructure, chemical composition, water retention capacity (WRC), extractability, viscosity and sedimentation). With the parameters used in this study, microfluidisation reduced wheat bran median particle size to 14.8 µm and disintegrated starch granules from the attached endosperm. This coincided with an increased extractability of starch and arabinoxylan. While the initial particle size was of minor importance, a higher pressure, larger number of passes and lower bran concentration during microfluidisation resulted in a smaller particle size, higher WRC and extractability, and an increased viscosity and stability in a 2% wheat bran suspension.


Assuntos
Fibras na Dieta/análise , Triticum/química , Endosperma/química , Tamanho da Partícula , Amido , Viscosidade , Água , Xilanos
7.
Chemosphere ; 240: 124909, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31550590

RESUMO

Environmental pollution and human health issues due to unrestricted electronic waste (e-waste) recycling activities have been reported at a number of locations. Among different e-waste recycling techniques, open burning of e-waste releases diverse metal(loid)s into the environment, which has aroused concern worldwide. In human health risk assessments (HHRAs), oral ingestion of soil can be a major route of exposure to many immobile soil contaminants. In vitro assays are currently being developed and validated to avoid overestimation of pollutants absorbed by the human body when calculating total pollutant concentrations in HHRAs. In this study, Cu, As, Cd, Sb, and Pb bioaccessibility in polluted soils (n = 10) from e-waste open burning sites at Agbogbloshie in Accra, Ghana, was assessed using an in vitro assay, the physiologically based extraction test. A bioaccessibility-corrected HHRA was then conducted to estimate the potential health risks to local inhabitants. The in vitro results (%) varied greatly among the different metal(loid)s (Cu: 1.3-60, As: 1.3-40, Cd: 4.2-67, Sb: 0.7-85, Pb: 4.1-57), and also showed marked variance between the gastric phase and small intestinal phase. The particle sizes of soil samples and chemical forms of metal(loid)s also influenced bioaccessibility values. Using these bioaccessibility values, both the hazard index and carcinogenic risk were calculated. The hazard index was above the threshold value (>1) for 5/10 samples, indicating a potential health risk to local inhabitants.


Assuntos
Resíduo Eletrônico , Metaloides/análise , Medição de Risco , Poluentes do Solo/farmacocinética , Disponibilidade Biológica , Exposição Dietética/efeitos adversos , Exposição Dietética/análise , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Monitoramento Ambiental , Gana , Humanos , Concentração de Íons de Hidrogênio , Metaloides/farmacocinética , Metaloides/toxicidade , Metais/análise , Metais/farmacocinética , Metais/toxicidade , Tamanho da Partícula , Reciclagem , Solo/química , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
8.
Chemosphere ; 240: 124916, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31563104

RESUMO

Cadmium contamination in greenhouse vegetable fields greatly limited the sustainable production especially of leafy vegetables. Hydroxyapatite (HAP), as a common soil amendment, has been widely used in the remediation of Cd-contaminated soils, while its remediation efficiency greatly depends on its particle sizes. In this study, a rhizobag pot experiment was conducted to investigate the effects of HAP (<60 nm, <12 µm and <80 µm) on bioavailability of Cd to celery grown in acidic and slightly Cd-contaminated greenhouse soil. The results suggested that HAP with the largest particle size (<80 µm) had the best effectiveness in reducing Cd uptake especially by the edible part of celery. Specifically, the increase in HAP (<80 µm) addition from 0.5% to 3% prominently reduced Cd concentrations in celery shoot by 19.6%-76.8% as compared with the untreated group. Also, adding HAP (<80 µm) especially at 3% significantly decreased translocation factor (TF) of Cd from celery root to shoot by 30.6% and reduced bioconcentration factor (BCF) of Cd from rhizosphere soil to celery shoot by 76.4%. These were predominantly associated with the significantly increased soil pH and the subsequently decreased soil CaCl2-Cd concentration after adding HAP (<80 µm). Overall, although rhizosphere soil pH was the key factor in controlling Cd uptake by edible celery and regulating BCF and TF of Cd, insignificant root-induced acidification had limited effect on the immobilization efficiency of Cd by HAP (<80 µm). In conclusion, HAP (<80 µm) has good potential for the remediation of Cd-contaminated greenhouse soils.


Assuntos
Apium/efeitos dos fármacos , Apium/metabolismo , Cádmio/farmacocinética , Durapatita/farmacologia , Poluentes do Solo/farmacocinética , Solo/química , Apium/crescimento & desenvolvimento , Biodegradação Ambiental , Disponibilidade Biológica , Cádmio/análise , Durapatita/química , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Rizosfera , Poluentes do Solo/análise
9.
J Agric Food Chem ; 68(2): 603-611, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31860287

RESUMO

Mixed Pickering emulsions were prepared by blending anionic nanocellulose-stabilized lipid droplets with cationic nanochitin-stabilized lipid droplets. Changes in the surface potential, particle size, shear viscosity, and morphology of the mixed emulsions were characterized when the droplet mixing ratio was varied. Emulsion properties could be tailored by altering the pH and mixing ratio. Surface potential measurements suggested that the nanochitin-coated lipid droplets adsorbed to the surfaces of the nanocellulose-coated lipid droplets, thereby dominating the overall electrical characteristics of the mixed emulsions. As a result, the mixed emulsions had better stability to coalescence than the single emulsions containing only nanocellulose-coated lipid droplets. Our results suggest that the physicochemical properties, shelf life, and functional performance of Pickering emulsions may be modulated by blending different kinds of particle-stabilized lipid droplets together.


Assuntos
Celulose/química , Quitina/química , Emulsões/química , Gotículas Lipídicas/química , Adsorção , Concentração de Íons de Hidrogênio , Nanopartículas/química , Tamanho da Partícula , Viscosidade
10.
J Agric Food Chem ; 68(2): 567-573, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31860290

RESUMO

Despite several published studies, the impact of emulsion droplet size on lipid oxidation rates is unclear. This could be because oil-in-water emulsions are typically polydisperse and the oxidation rate of individual droplets is difficult to discern. Flow cytometry is a technique for studying individual cells and their subpopulations using fluorescence technologies, which is possible to be used in studying individual emulsion droplets. Typical emulsion droplets are too small to be visualized by flow cytometer so emulsions were prepared to have droplets >2 µm that were stabilized by weighting agent and xanthan gum to minimize creaming during storage. A radical-sensitive fluorescence probe (BODIPY665/676) was added to the lipid used to prepare the emulsion so that the susceptibility of individual emulsion droplets could be determined. The results showed that in a polydisperse emulsion system, small droplets were oxidized faster than large droplets. A conventional method was also carried out by blending two emulsions with different droplet sizes and oil densities, and results were in agreement with the observation obtained from flow cytometry. As a new approach, flow cytometry could be utilized in emulsion studies to reveal insights of lipid oxidation mechanisms in individual droplets.


Assuntos
Emulsões/química , Citometria de Fluxo/métodos , Lipídeos/química , Água/química , Oxirredução , Tamanho da Partícula
11.
Chemosphere ; 240: 124953, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31574435

RESUMO

Chemical characterization of PM2.5 and PM10 is important to identify potential compounds that induce biological responses that translate into cardio-respiratory health problems. This study shows the reliability of the use of crystalline phases, identified in samples from receptor sites, as source markers, helping researchers to infer the main sources of air pollution, even without the use of receptor models. PM2.5 and PM10 samples were collected at two sites in an urban industrialized region located at southeast of Brazil and analyzed by Synchrotron X-ray Diffraction to identify crystalline compounds. Results show 5 PM10 and PM2.5 species not previously reported in the literature. We propose reaction mechanisms for these species and identify specific sources for each crystalline phase found: BaTiO3 was found in PM10 receptor samples and proved to be a vehicular marker formed during brake action; maghemite (γ-Fe2O3), pyracmonite [(NH4)3Fe(SO4)3], ammonium perchlorate (NH3OHClO4) and potassium ferrate (K2Fe2O4) were found in PM2.5 proved to be markers of industrial activities. The crystalline phases found in PM samples from receptor sites and the mechanisms of reactions showed the reliability of the use of crystalline phases as source markers in the identification of potential sources of air pollution without misinterpretation of the likely source.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Monitoramento Ambiental/métodos , Material Particulado/análise , Material Particulado/química , Sulfato de Amônio/análise , Compostos de Bário/análise , Brasil , Compostos Férricos/análise , Indústrias , Compostos de Ferro/análise , Tamanho da Partícula , Percloratos/análise , Compostos de Potássio/análise , Compostos de Amônio Quaternário/análise , Reprodutibilidade dos Testes , Síncrotrons , Titânio/análise , Difração de Raios X/métodos
12.
Food Chem ; 308: 125674, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31669944

RESUMO

Cadmium-contaminated rice has been a serious food safety issue in China. In this research, carboxymethyl rice starch (CMS) from cadmium-contaminated rice and native rice was prepared to remove the cadmium in rice. The preparation of native rice starch (NRS) and starch from cadmium-contaminated rice (Cd-CRS) was similar, and carboxymethyl starch was prepared following the same steps. A single factor experiment was performed to obtain the carboxymethyl starch prepared under the optimal conditions. Cadmium content was reduced from 0.38 mg/kg to 0.04 mg/kg after alkalization. The physical properties, including particle size, degree of crystallinity, water absorption and freeze-thaw stability, of NRS and Cd-CRS and their carboxymethyl starches were studied. The results showed that the cadmium was significantly removed after extracting starch from cadmium-contaminated rice by alkalization and carboxymethylation. Then, starch samples and carboxymethyl starch samples were characterized. All results showed no obvious difference between Cd-CMS and NCMS, indicating that carboxymethyl starch from cadmium-contaminated rice could be widely used in both food and nonfood industries.


Assuntos
Cádmio/análise , Oryza/química , Amido/análogos & derivados , Contaminação de Alimentos , Inocuidade dos Alimentos , Tamanho da Partícula , Amido/química , Água
13.
Food Chem ; 308: 125573, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31639598

RESUMO

In this study an active antimicrobial packaging based on the controlled release of Allyl isothiocyanate (AITC) from mustard seed was designed. The effect of fat content and particle size of ground mustard seeds on formation and release of AITC was investigated and the underlying mechanisms were highlighted. A smaller size of mustard particles resulted in more sinigrin conversion to AITC and a higher release of AITC in the headspace. The fat content has an important role on AITC release, a decreased fat content decreased AITC levels in the particles and increased the amount of AITC in the headspace. Based on the results of the sinigrin hydrolysis, the AITC surface exchange rate and the AITC fat solubility, an overall picture of the factors influencing the AITC release from the particles is proposed, which describes formation of AITC and its partitioning between the compartments of the particles and the headspace.


Assuntos
Gorduras/química , Isotiocianatos/química , Mostardeira/química , Antibacterianos , Glucosinolatos/química , Tamanho da Partícula , Embalagem de Produtos , Sementes/química
14.
J Sci Food Agric ; 100(1): 110-118, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31436316

RESUMO

BACKGROUND: Pectin is an intriguing polymer, which is usually regarded as a byproduct from agricultural and biological processes. In previous studies, ultrasound treatment has been explored to improve the functionality of pectin but most of that work focused on aspects of molecular structure and the chemical properties of pectin. In this study, we utilized ultrasound treatment to modify the physiochemical properties of pectin. Using ultrasound treatment, we evaluated the emulsifying capability of pectin as a function of ultrasonic time and power density, using a response surface approach. A very potent yet unstable coffee-like aroma compound, 2-furfurylthiol, was also used for comparing the encapsulation feasibility of emulsion made with original pectin and ultrasound-treated pectin. RESULTS: Our results showed that the particle size of pectin was highly correlated with power density and ultrasound time. Approximately 370 nm of pectin particle size could be reached at a power density of 1.06 W mL-1 for 40 min. Ultrasound treatment increased emulsion droplet size but significantly improved emulsifying capacities, such as centrifugal stability and surface loading, although it was highly dependent upon the ultrasound treatment condition. When used as the encapsulation wall material, the ultrasound-modified pectin had significantly enhanced performance compared with the original, in terms of flavor retention over time at 45 °C and 65 °C. CONCLUSION: Ultrasound treatment was able to modify the physiochemical properties of pectin, which thus improved emulsification stability and encapsulation feasibility by forming a thicker layer at the oil / water interface to protect the core materials. © 2019 Society of Chemical Industry.


Assuntos
Furanos/química , Pectinas/química , Compostos de Sulfidrila/química , Composição de Medicamentos , Emulsificantes/química , Emulsificantes/efeitos da radiação , Emulsões/química , Tamanho da Partícula , Pectinas/efeitos da radiação , Ultrassom
15.
J Sci Food Agric ; 100(1): 129-138, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31452202

RESUMO

BACKGROUND: Capsaicin, as a major pungent ingredient of peppers, has many health benefits. However, the strong irritation effect of capsaicin inhibits its application in the food industry. Emulsions can be an effective approach to alleviate the irritation. RESULTS: In this study, we used tocopheryl polyethylene glycol 1000 succinate (TPGS) as an emulsifier to prepare capsaicin emulsions through high-pressure homogenization. Capsaicin emulsions with a particle size of about 100 nm, -36.4 mV zeta potential, and 91.9% encapsulation efficiency were prepared successfully and showed better environmental stability and higher antioxidant activity. Emulsions reduced the cumulative release of capsaicin and had no toxic effect on buffalo rat liver (BRL-3A) cells. Moreover, the gastrointestinal injury model of rats showed that emulsions reduced the strong irritation of capsaicin. CONCLUSION: This work provides a theoretical basis for the application of irritant ingredients in food industry. © 2019 Society of Chemical Industry.


Assuntos
Capsaicina/química , Capsaicina/metabolismo , Trato Gastrointestinal/metabolismo , Animais , Emulsificantes/química , Emulsões/química , Emulsões/metabolismo , Masculino , Tamanho da Partícula , Ratos , Ratos Sprague-Dawley , Vitamina E/química
16.
Food Chem ; 306: 125300, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31562927

RESUMO

Chlorophyll is a valuable bioactive compound, which is used as a natural food coloring agent and a photosensitizer for photodynamic therapy because of its antioxidant properties, antimutagenic ability, and near-infrared fluorescence. However, chlorophyll is unstable when it comes to retaining its antioxidant activity, when exposed to oxygen, high temperature, or light environments. To enhance the stability of chlorophyll, a polymer encapsulation method was proposed. Polycaprolactone (PCL) was employed to encapsulate the chlorophyll, and the particles size of the composites was controlled through droplet microfluidics. The composites (chlorophyll-encapsulated PCL particles) were characterized through UV-VIS spectrometry, SEM, optical microscopy, and light exposure. The particles were spherical, with diameters adjustable from 68 to 247 µm. Additionally, the chlorophyll-encapsulated PCL particles exhibited considerably prolonged chlorophyll stability. The solid microparticle is more convenient for storage and transportation, and have great potential for application in the food industry.


Assuntos
Clorofila/química , Poliésteres/química , Microfluídica/métodos , Tamanho da Partícula
17.
Food Chem ; 306: 125619, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31606630

RESUMO

We evaluated the correlation between the interfacial characteristics of solid lipid nanoparticles (SLNs) and the interfacial/colloidal stability of SLN-stabilized emulsions. Herein, the interfacial properties of SLNs, particularly the surface load (Γs) of emulsifiers, were tuned by controlling the type/concentration of emulsifier used to prepare the SLNs. Increasing the Γs decreased the contact angle at the oil-water interface, which enhanced the displacement free energy of the SLNs at the interface. Moreover, the Γs of emulsifiers bound to the surface of SLNs covering oil droplets was linearly correlated with the SLN-own Γs. The size/ζ-potential of emulsions stabilized by SLNs covered by the highest concentration of emulsifiers was unchanged for 1 month, indicating good emulsion stability. The interfacial/colloidal stability of SLN-stabilized emulsions was thus enhanced by increasing the emulsifier concentration used to produce the SLNs. This study provides baseline data for developing SLN-stabilized emulsions for the food, cosmetic, and pharmaceutical industries.


Assuntos
Lipídeos/química , Nanopartículas , Emulsificantes , Emulsões , Tamanho da Partícula , Água/química
18.
Chemosphere ; 238: 124600, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31446277

RESUMO

A high-gravity rotating packed bed (HiGee RPB) is very efficient at removing pollution because it exerts a strong high centrifugal and allows tiny droplets to form, which allows the control of gaseous and particulate air pollution. In this study, fine particles that are removed from integrated circuit (IC) chip carbonization process using a RPB are evaluated under different high gravity factors and liquid-to-gas ratios. The greatest number of particles captured per energy consumption is 17.77 mg kWh-1 in a RPB. This allow greater energy efficiency for the HiGee technology prevents an air-energy nexus. The maximum available particle removal efficiency for a RPB is determined using a response surface model (RSM). 99.5% of particles are removed at a high gravity factor of 262 and a liquid-to-gas ratio of 0.24. A semi-theoretical model is developed to determine the particle removal efficiency individually in packing and cavity zones of the RPB. More particles are removed in a cavity zone than in the packing zone as the high gravity factor increases. An empirical model shows that the particle removal efficiency depends on the operating factors. Finally, a comparison analysis of particulate matter treatment in various types of RPB is used to validate the performance in terms of particle removal using high-gravity technology for different industries.


Assuntos
Poluição Ambiental/análise , Recuperação e Remediação Ambiental/métodos , Material Particulado/análise , Carbono , Centrifugação/métodos , Gases , Tamanho da Partícula
19.
Food Chem ; 305: 125475, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31518841

RESUMO

Pea protein-stabilized nanoemulsions were prepared to encapsulate vitamin D with the aim to develop novel non-dairy functional foods for vitamin D fortifications. Homogenization conditions of 20 kpsi and two homogenization cycles were identified as optimal conditions for producing stable nanoemulsions. The nanoemulsions exhibited controllable sizes (170-350 nm), good stability with zeta-potential of -25 mV, and high vitamin encapsulation efficiency (94-96%). Cellular uptake efficiency of small sized nanoemulsions (233 nm) was ~2.5 times higher than large sized nanoemulsions (350 nm). Interestingly, protein-based nanoemulsions exhibited significantly higher cellular uptake than emulsions prepared using a combination of protein and lecithin. The vitamin D transport efficiency across Caco-2 cells for small sized nanoemulsions (233 nm) was ~5.3 times greater than free vitamin D suspension. This research demonstrated that pea protein can be used as an effective emulsifier for preparing food nanoemulsions, which may enhance vitamin D bioavailability and improve vitamin deficiency status in aged population.


Assuntos
Emulsões/química , Nanoestruturas/química , Proteínas de Ervilha/química , Vitamina D/química , Células CACO-2 , Sobrevivência Celular , Emulsificantes/química , Humanos , Lecitinas/química , Nanoestruturas/toxicidade , Tamanho da Partícula , Pressão , Estabilidade Proteica , Vitamina D/metabolismo
20.
Food Chem ; 305: 125476, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31525589

RESUMO

Octenylsuccinate quinoa starch (OSQS) granule that stabilized Pickering emulsion gel with different gel networks by modulating the oil volume fraction (Φ) was developed as a carrier for lutein. Pickering emulsion gels stabilized by OSQS were achieved at Φ values ranging from 30% to 60%. Increasing Φ progressively increased the droplet size, storage modulus, and apparent viscosity, resulting in the formation of gel-like structure. Confocal laser scanning microscopy showed that OSQS formed a densely packed layer at the oil/water interface, the degree of aggregation between droplets increased, and the gel network enhanced through droplet flocculation with increasing Φ. After 31 days of storage, the retention index of lutein in the emulsion gel could reach 55.38%, and the corresponding half-life times increased from 12 to 41 days. This study will be useful for designing starch-based Pickering emulsion gel with tunable gel network and desirable characteristics as delivery carrier of sensitive bioactive compounds.


Assuntos
Chenopodium quinoa/metabolismo , Géis/química , Luteína/química , Amido/química , Succinatos/química , Emulsões/química , Meia-Vida , Luteína/metabolismo , Microscopia Confocal , Tamanho da Partícula , Reologia
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