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1.
J Agric Food Chem ; 67(40): 11129-11136, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31487456

RESUMO

4-Amion-2,2,6,6-tetramethylpiperidine (Temp) was grafted into sodium lignosulfonate (SL) to obtain hindered amine-modified lignosulfonate (SL-Temp). Then, the polymer surfactant (SL-Temp-CTAB) was prepared using cetyltrimethylammonium bromide (CTAB) and SL-Temp. Obtained SL-Temp-CTAB was used as an emulsifier to prepare a green emulsifiable concentrate (EC) of avermectin (AVM), which shows good emulsifying property and storage stability. The prepared AVM green EC can form AVM-loaded microspheres with nanometer particle size distribution after emulsification in water. After ultraviolet irradiation for 70 h, the AVM retention rate of the green EC prepared using SL-Temp-CTAB was 75.8%, which is much higher than that of commercial EC (0.4%) and the green EC prepared using unmodified SL (31.4%). Moreover, the AVM green EC prepared using SL-Temp-CTAB has slow-release performance, and the release equilibrium time is 5.3 times the commercial EC. Therefore, the newly prepared AVM green EC using a lignin-based functional emulsifier shows good antiphotolysis and slow-release performance compared to the traditional EC.


Assuntos
Aminas/química , Emulsificantes/síntese química , Lignina/química , Cetrimônio/química , Emulsificantes/química , Emulsões/química , Cinética , Lignina/análogos & derivados , Espectroscopia de Ressonância Magnética , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier
2.
J Agric Food Chem ; 67(39): 10904-10912, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31508953

RESUMO

High-order multiple emulsions are of great interest in both fundamental research and industrial applications as vehicles for their encapsulation capability of actives. In this work, we report a hierarchically multicompartmental highly stable triple emulsion by emulsifying and assembling of natural Quillaja saponin. Water-in-oil-in-(oil-in-water) (W2/O2/(O1/W1)) triple emulsion indicates that the compartmented system consisted of surfaced saponin-coated nanodroplets (SNDs) and dispersed oil globules, which in turn contained smaller aqueous droplets. The effects of formulation parameters, including lipophilic emulsifier content, oil fraction, and SND concentration, on the formation of multiple emulsions were systematically investigated. The assembly into fibrillar network of SNDs at the outer oil-water interface effectively protected the triple emulsion droplets against flocculation and coalescence, and strongly prevented the osmotic-driven water diffusion between the internal water droplets and the external water phase, thus contributing to superior stability during 180 days storage. All of these characteristics make the multicompartmentalized emulsions suitable to co-encapsulate a hydrophilic bioactive (gardenia blue) and two hydrophobic bioactives (eapsanthin and curcumin) in a single emulsion droplet hierarchically for the segregation and protection of multiple cargos. This approach offers a promising route toward accessing the next generation of functional deliveries and encapsulation strategies.


Assuntos
Curcumina/química , Sistemas de Liberação de Medicamentos/métodos , Extratos Vegetais/química , Quillaja/química , Saponinas/química , Composição de Medicamentos , Sistemas de Liberação de Medicamentos/instrumentação , Emulsificantes/química , Emulsões/química , Glucosídeos/química , Óleos/química , Tamanho da Partícula , Água/química
3.
J Agric Food Chem ; 67(39): 10937-10946, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31508960

RESUMO

This paper attempted to construct a high internal phase emulsion (HIPE) through altering interfacial behaviors using the electrostatic interaction between positive chitosan and negative octenyl succinic anhydride (OSA) starch. The partial polysaccharide complex of OSA starch/chitosan was used to stabilize HIPE, which was able to adsorb at the oil droplet interface and prevent the coalescence of oil droplets. The wettability of OSA starch was enhanced with the addition of positively charged chitosan, leading to the formation of partial complexes. The impact of pH and concentration of chitosan on the droplet size, surface charge, and interface behavior were investigated, and the formation of the polysaccharide complex was further confirmed by atomic force microscopy. The presence of the OSA starch/chitosan complex facilitated the formation of stable HIPE with a gel-like structure and satisfactory centrifugal and oxidative stability. These results are useful to provide information for fabricating polysaccharide-based HIPE delivery systems, which may help expand their application in the food industry.


Assuntos
Quitosana/química , Amido/análogos & derivados , Emulsões/química , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Amido/química , Anidridos Succínicos/química
4.
J Agric Food Chem ; 67(38): 10587-10594, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31497957

RESUMO

Inefficient usage and overdosage of conventional pesticide formulations has resulted in large economic losses and environmental pollution due to their poor water solubility and weak adhesion to foliage. In order to develop a green and efficient pesticide formulation, a kind of alkyd resin (AR) based on vegetable oil was first synthesized and used to fabricate the lambda-cyhalothrin/AR (LC/AR) nanoemulsion via in situ phase inverse emulsification, and its properties were then investigated. Results showed that the particle size of the LC/AR nanoemulsion was 50-150 nm with maximum LC loading capacity of as much as 40.9 wt %, high encapsulation efficiency >90%, and great stability in multiple environments. The LC/AR nanoemulsion exhibited better controlled release characteristics compared with LC commercial formulations, and a stronger adhesion on the foliage of the resulted nanoemulsion was also observed, which was attributed to low surface tension and strong interactions with foliar surfaces.


Assuntos
Preparações de Ação Retardada/química , Composição de Medicamentos/métodos , Nitrilos/química , Praguicidas/química , Piretrinas/química , Emulsões/química , Tamanho da Partícula , Solubilidade
5.
J Agric Food Chem ; 67(36): 10165-10173, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31398024

RESUMO

Chin-brick tea polysaccharide conjugates (TPC-C) were prepared to study their emulsion capabilities. Interfacial tension and the effects of some factors, such as storage time, metal ion concentrations (Na+, Ca2+), pH (2.0-8.0), and heat treatment (70-100 °C) on the emulsions stabilized by TPC-C were studied. The interfacial tension of TPC-C (10.88 mN/m) was lower than that of gum arabic (15.18 mN/m) at a concentration of 0.08%. As the TPC-C concentration increased from 0.1 to 3.0 wt %, the mean particle diameter (MPD) (d32) of emulsions stabilized by TPC-C decreased from 1.88 to 0.16 µm. Furthermore, at a concentration of 0.5 wt % or higher, the MPD (d32) of emulsions stabilized by TPC-C at 25 and 60 °C for 10 days was between 0.20 and 0.50 µm. In the tested pH conditions from 2.0 to 8.0, the MPD (d32) of emulsions stabilized by 2.0 wt % TPC-C was less than 0.20 µm. At Na+ concentration conditions between 0.10 and 0.50 mol/L, the MPD (d32) of emulsions was between 0.19 and 0.20 µm, and the zeta potential values varied from -34.10 to -32.60 mV. However, with an increasing Ca2+ concentration from 0.01 to 0.05 mol/L, the MPD (d32) of emulsions was between 0.20 and 21.65 µm, and the zeta potential raised sharply from -34.10 to -28.46 mV. The emulsions stabilized by TPC-C have a decent storage stability after a high-temperature heat treatment. Overall, tea polysaccharide conjugates strongly stabilized the emulsions, which support their new application as natural emulsifiers.


Assuntos
Camellia sinensis/química , Emulsificantes/química , Extratos Vegetais/química , Polissacarídeos/química , Emulsões/química , Concentração de Íons de Hidrogênio , Tamanho da Partícula
6.
J Agric Food Chem ; 67(36): 10155-10164, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31433944

RESUMO

Stabilization of Pickering emulsions via particles of biological origin exhibits a great potential to be widely applied in food, cosmetic, or biomedicine formulation because of their excellent biocompatibility, biodegradability, and functional properties. This paper describes the successful development of a bioderived GroEL protein nanobarrel as a Pickering stabilizer and its protective properties on ß-carotene in dispersed oil phase, as a model of labile bioactive compounds. It is shown that the GroEL nanobarrel is highly surface-active and allows the formation of Pickering emulsion by physical adsorption at the oil/water interface. The optimized formulation for generating a stable submicron oil droplet by ultrasonication includes a GroEL concentration of 0.05-0.45 wt % with an oil/water volume ratio of 0.05-0.35. The as-prepared Pickering emulsion shows pH-responsive emulsification/demulsification transition and excellent stability at temperatures less than 65 °C and ionic strength (with NaCl addition) up to 500 mM. Meanwhile, the emulsion tends to form a gel-like network structure with the oil/water ratio increasing. Finally, we demonstrate that possible factors of oxidant, reducing agent, UV radiation, and sucrose have sequentially decreasing to no effect on the stability of ß-carotene encapsulated in GroEL-stabilized Pickering emulsion and that higher GroEL concentration can significantly reduce ß-carotene degradation rate, thus ensuring more efficient long-term storage. We believe that the emulsion system supported by the GroEL nanobarrel could be developed to a viable tool for delivering lipophilic bioactive compounds.


Assuntos
Chaperoninas/química , Fixadores/química , Óleos/química , Água/química , Emulsões/química , Interações Hidrofóbicas e Hidrofílicas , Nanoestruturas/química , Concentração Osmolar , Tamanho da Partícula , Temperatura Ambiente , beta Caroteno/química
7.
J Agric Food Chem ; 67(36): 10195-10206, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31436982

RESUMO

Pea protein hydrolysate (PPH) is successfully conjugated with gum arabic (GA) through Maillard-driven chemistry. The effect of cross-linking conjugation on the structure, solubility, volatile substances, emulsification, and antioxidative activity of glyco-PPH is investigated, and found to improve all properties. The formation of glyco-PPH is confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), Fourier-transform infrared (FTIR), and scanning electron microscopy (SEM). Size exclusion chromatography-multi angle light scattering (SEC-MALS) unveils that the maximum molecular mass of glyco-PPH occurs after 1 day of conjugation and approximately 1.2 mol of gum arabic conjugates on one mole of PPH. Headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) reveals the odor changes of glycoprotein before and after cross-linking. We have also prepared oil-in-water emulsions using glyco-PPH, which have enhanced physical stability against pH changes and chemical stability against lipid oxidation. The mechanism proposed involves Maillard-driven synthesis of the cross-linked PPH-GA conjugates, which increase the surface hydrophilicity and steric hindrance of glyco-PPH. These findings could provide a rational foundation for tailoring the physicochemical properties and functionalities of plant-based protein, which are attractive for food and functional materials applications.


Assuntos
Aromatizantes/síntese química , Goma Arábica/química , Proteínas de Ervilha/química , Antioxidantes/química , Emulsões/química , Aromatizantes/química , Interações Hidrofóbicas e Hidrofílicas , Reação de Maillard , Hidrolisados de Proteína/química , Solubilidade
8.
J Agric Food Chem ; 67(35): 9719-9726, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31398015

RESUMO

Pickering high internal phase emulsions (HIPEs) are normally highly concentrated emulsions stabilized by colloidal particles with a minimum internal phase volume fraction of 0.74. They have received considerable attention in many fields, including pharmaceuticals, tissue engineering, foods, and personal care products. The aim of this perspective is to update the current knowledge on the field of protein-based Pickering HIPEs, emphasizing those aspects that need to be explored and clarified. Research progress in constructing HIPEs by protein-type colloid particles and promising research trends in basic research and potential applications were highlighted. Promising studies in this field include (1) clarifying bioavailability and evolution of activity of active ingredients in Pickering HIPEs by oral administration, (2) constructing a Pickering interfacial catalysis platform using protein colloidal particles, and (3) expanding the emerging applications of Pickering HIPEs in fields, such as partially hydrogenated oil replacers, probiotic encapsulation, and the template for porous materials.


Assuntos
Suplementos Nutricionais/análise , Emulsões/química , Proteínas/química , Coloides/química , Sistemas de Liberação de Medicamentos/instrumentação , Sistemas de Liberação de Medicamentos/métodos , Excipientes/química , Nanopartículas/química , Tamanho da Partícula , Porosidade
9.
J Agric Food Chem ; 67(35): 9926-9933, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31398027

RESUMO

Vitamins and flavonoids are two kinds of essential trace bioactives which are prone to photodegradation during food processing and storage. In this study, a particle-stabilized water-in-water (W/W) emulsion system composed of soy protein isolate (SPI) and guar gum (GG) was applied in loading riboflavin. Based on the significant binding affinity differences of SPI (Ka = 1.11 × 105 L mol-1) and GG (Ka = 9.00 × 103 L mol-1) to riboflavin, this hydrophilic and light-sensitive bioactive compound was loaded in SPI-rich droplets. Confocal images indicated that a stable microstructure of SPI-rich droplets suspended in GG-rich continuous phase was successfully constructed by manipulating the proportion of the two polymeric components and using zein-based particles (ZPs) as stabilizers. These negatively charged particles modified by pectin with a hydrodynamic diameter of 533 ± 5.7 nm were able to adsorb at the SPI/GG interface and subsequently stabilized the SPI-in-GG emulsion. Fluorescence spectra of riboflavin suggested that the formation of such W/W emulsion could effectively delay the photodegradation of riboflavin during an 8 h ultraviolet irradiation, and its color was maintained to a maximum extent. Therefore, this structured W/W emulsion could be a desired architecture for delivering light-sensitive cargo.


Assuntos
Riboflavina/química , Água/química , Zeína/química , Composição de Medicamentos , Emulsões/química , Excipientes/química , Galactanos/química , Interações Hidrofóbicas e Hidrofílicas , Cinética , Mananas/química , Tamanho da Partícula , Fotólise , Gomas Vegetais/química
10.
Int J Nanomedicine ; 14: 5435-5448, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31409997

RESUMO

Background: Ramipril (RMP) suffers from poor aqueous solubility along with sensitivity to mechanical stress, heat, and moisture. The aim of the current study is to improve RMP solubility and stability by designing solid self-nanoemulsifying drug delivery system (S-SNEDDS) as tablet. Methods: The drug was initially incorporated in different liquid formulations (L-SNEDDS) which were evaluated by equilibrium solubility, droplet size, and zeta potential studies. The optimized formulation was solidified into S-SNEDDS powder by the adsorbent Syloid® and compressed into a self-nanoemulsifying tablet (T-SNEDDS). The optimized tablet was evaluated by drug content uniformity, hardness, friability, disintegration, and dissolution tests. Furthermore, pure RMP, optimized L-SNEDDS, and T-SNEDDS were enrolled in accelerated and long-term stability studies. Results: Among various liquid formulations, F5 L-SNEDDS [capmul MCM/transcutol/HCO-30 (25/25/50%w/w)] showed relatively high drug solubility, nano-scaled droplet size, and high negative zeta potential value. The optimized SNEDDS solidification with Syloid® at ratio (1:1) resulted in a compressible powder with an excellent flowability. The optimized tablet (T-SNEDDS) showed accepted content uniformity, hardness, friability, and disintegration time (<15 minutes). The optimized L-SNEDDS, S-SNEDDS, and T-SNEDDS showed superior enhancement of RMP dissolution compared to the pure drug. Most importantly, T-SNEDDS showed significant (P<0.05) improvement of RMP stability compared to the pure drug and L-SNEDDS in both accelerated and long-term stability studies. Conclusion: RMP-loaded T-SNEDDS offers a potential oral dosage form that provides combined improvement of RMP dissolution and chemical stability.


Assuntos
Sistemas de Liberação de Medicamentos , Emulsões/química , Nanopartículas/química , Ramipril/farmacologia , Administração Oral , Adsorção , Disponibilidade Biológica , Varredura Diferencial de Calorimetria , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Dureza , Nanopartículas/ultraestrutura , Tamanho da Partícula , Controle de Qualidade , Solubilidade , Eletricidade Estática , Comprimidos/química , Fatores de Tempo , Difração de Raios X
11.
Int J Nanomedicine ; 14: 5449-5475, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31409998

RESUMO

Purpose: We created and evaluated an enhanced topical delivery system featuring a combination of highly skin-permeable growth factors (GFs), quercetin (QCN), and oxygen; these synergistically accelerated re-epithelialization and granulation tissue formation of/in diabetic wounds by increasing the levels of GFs and antioxidants, and the oxygen partial pressure, at the wound site. Methods: To enhance the therapeutic effects of exogenous administration of GFs for the treatment of diabetic wounds, we prepared highly skin-permeable GF complexes comprised of epidermal growth factor (EGF), insulin-like growth factor-I (IGF-I), platelet-derived growth factor-A (PDGF-A), and basic fibroblast growth factor (bFGF), genetically attached, via the N-termini, to a low-molecular-weight protamine (LMWP) to form LMWP-EGF, LMWP-IGF-I, LMWP-PDGF-A, and LMWP-bFGF, respectively. Furthermore, quercetin (QCN)- and oxygen-carrying 1-bromoperfluorooctane (PFOB)-loaded nanoemulsions (QCN-NE and OXY-PFOB-NE) were developed to improve the topical delivery of QCN and oxygen, respectively. After confirming the enhanced penetration of LMWP-GFs, QCN-NE, and oxygen delivered from OXY-PFOB-NE across human epidermis, we evaluated the effects of combining LMWP-GFs, QCN-NE, and OXY-PFOB-NE on proliferation of keratinocytes and fibroblasts, and the chronic wound closure rate of a diabetic mouse model. Results: The optimal ratios of LMWP-EGF, LMWP-IGF-I, LMWP-PDGF-A, LMWP-bFGF, QCN-NE, and OXY-PFOB-NE were 1, 1, 0.02, 0.02, 0.2, and 60, respectively. Moreover, a Carbopol hydrogel containing LMWP-GFs, QCN-NE, and OXY-PFOB-NE (LMWP-GFs/QCN-NE/OXY-PFOB-NE-GEL) significantly improved scratch-wound recovery of keratinocytes and fibroblasts in vitro compared to that afforded by hydrogels containing each component alone. LMWP-GFs/QCN-NE/OXY-PFOB-NE-GEL significantly accelerated wound-healing in a diabetic mouse model, decreasing wound size by 54 and 35% compared to the vehicle and LMWP-GFs, respectively. Conclusion: LMWP-GFs/QCN-NE/OXY-PFOB-NE-GEL synergistically accelerated the healing of chronic wounds, exerting both rapid and prolonged effects.


Assuntos
Diabetes Mellitus/patologia , Hidrogéis/química , Fator de Crescimento Insulin-Like I/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Oxigênio/metabolismo , Quercetina/farmacologia , Absorção Cutânea , Cicatrização/efeitos dos fármacos , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Colágeno/biossíntese , Modelos Animais de Doenças , Emulsões/química , Fator de Crescimento Epidérmico/farmacologia , Epiderme/efeitos dos fármacos , Fator 2 de Crescimento de Fibroblastos/farmacologia , Humanos , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Peso Molecular , Nanopartículas/química , Nanopartículas/ultraestrutura , Octanos/química , Fator de Crescimento Derivado de Plaquetas/farmacologia , Protaminas/química , Absorção Cutânea/efeitos dos fármacos
12.
J Agric Food Chem ; 67(34): 9543-9550, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31379164

RESUMO

This study aimed to reveal the mechanisms underlying the interaction between condensed tannins (CTs) and bile salts. The interaction mechanism was analyzed by transmission electron microscopy, exposure to various physicochemical conditions, electrophoresis, fluorescence spectroscopy, isothermal titration calorimetry, and molecular modeling. A new complex was formed from CTs and bile salts. The complex showed a negative enthalpy change and a positive entropy change, demonstrating that the main thermodynamic driving force was both entropy and enthalpy and indicating that binding occurred through hydrogen bonds and hydrophobic interactions. The analysis of the effects of CTs on the stability and digestion properties of bile salt emulsions indicated that CTs were able to inhibit lipid digestion to an extent. Our findings may provide evidence that foods rich in CTs offer health benefits by aggregating with bile salts and reducing the absorption of fat.


Assuntos
Ácidos e Sais Biliares/química , Proantocianidinas/química , Ácidos e Sais Biliares/metabolismo , Calorimetria , Emulsões/química , Emulsões/metabolismo , Entropia , Ligações de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Proantocianidinas/metabolismo , Termodinâmica
13.
Chem Pharm Bull (Tokyo) ; 67(8): 786-794, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31366828

RESUMO

Teriflunomide (TEF, A771726) is the active metabolite of leflunomide (LEF), a disease-modifying anti-rheumatic drug. The main purpose of this study was to develop and evaluate water-in-oil (W/O) microemulsion formulation of TEF. The W/O microemulsion was optimized formula is the physical and chemical stability of lecithin, ethanol, isopropyl myristate (IPM) and water (20.65/20.78/41.52/17.05 w/w) by using the pseudo-ternary phase diagram and the average droplet size is about 40 nm. The permeability of TEF microemulsion is about 6 times higher than control group in vitro penetration test. The results of anti-inflammatory effect showed that compared with the control group, the external TEF microemulsion group could significantly inhibit swelling of paw in rats, and no significant difference compared with oral LEF group. The results of hepatotoxicity test show that there were normal content of alanine aminotransferase (ALT)/aspartate aminotransferase (AST) and no obvious inflammatory infiltration of TEF microemulsion group compared with LEF group. The plasma concentration curve showed that compared with LEF group, the peak concentration of TEF microemulsion group was decreased, the half-life (t1/2) was prolonged, and the relative bioavailability of TEF microemulsion was 75.35%. These results suggest that TEF W/O microemulsion can be used as a promising preparation to play an anti-inflammatory role while significantly reducing hepatotoxicity.


Assuntos
Antirreumáticos/farmacologia , Crotonatos/farmacologia , Sistemas de Liberação de Medicamentos , Edema/tratamento farmacológico , Toluidinas/farmacologia , Animais , Antirreumáticos/química , Crotonatos/química , Composição de Medicamentos , Edema/patologia , Emulsões/síntese química , Emulsões/química , Estrutura Molecular , Óleos/química , Medição da Dor , Ratos , Ratos Sprague-Dawley , Toluidinas/química , Água/química
14.
Food Chem ; 299: 125164, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31319345

RESUMO

Control of lipid digestibility by various food components has received great attention in recent decades. However, there is limited literature on investigating the synergistic effect of exogenous emulsifiers and endogenous sodium cholate (SC) on lipid digestion in a simulated physiological crowded medium. In this work, the synergistic interaction of Tween80 and SC according to the regular solution theory, and the hydrolysis of lipid emulsions containing tricaprylin, glyceryltrioleate or soybean oil in crowding medium was studied. The results show that emulsions stabilized by a combination of Tween80 and SC showed higher digestion rate and transformation than those with Tween80 or SC. The digestion rate could be increased by polyethylene glycols (PEGn) with varying crowding degree. The denaturation temperature of the lipase was increased in macromolecular crowded medium. This work allows for better understanding of the interaction between the amphiphiles and the macromolecular crowding effect on lipase digestion in the physiological environment.


Assuntos
Emulsificantes/farmacocinética , Lipídeos/farmacocinética , Polissorbatos/farmacocinética , Colato de Sódio/farmacocinética , Caprilatos/metabolismo , Digestão , Emulsões/química , Emulsões/farmacocinética , Hidrólise , Lipase/química , Lipase/metabolismo , Lipídeos/química , Polietilenoglicóis , Polissorbatos/química , Colato de Sódio/química , Óleo de Soja/metabolismo , Temperatura Ambiente , Triglicerídeos/metabolismo
15.
Food Chem ; 298: 125079, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260959

RESUMO

Citral-in-water emulsions were prepared with two different essential oil concentrations of 2.5 and 5.0% (w/w), then spray-dried in the presence of the same amount of maltodextrins (20%). The microcapsules were prepared with two different emulsifier compositions: monolayer microcapsules (ML) stabilized by sodium caseinate alone and layer-by-layer microcapsules (LBL) stabilized by sodium caseinate and pectin. The encapsulation efficiency was higher for LBL microcapsules (e.g. 99.6 ±â€¯0.4% for 2.5% citral) than that for ML ones (e.g. 78.6 ±â€¯0.6% for 2.5% citral) which confirm that the additional pectin layer was able to protect citral during the spray-drying process whatever citral concentration. Furthermore, our results showed that the antibacterial activity of the obtained microcapsules significantly depends on both citral concentration and interfacial membrane composition. The presence of two layers surrounding the citral droplets may result in a progressive and controlled release of the encapsulated citral.


Assuntos
Emulsões/química , Monoterpenos/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Cápsulas/química , Caseínas/química , Dessecação , Listeria/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Tamanho da Partícula , Pectinas/química , Polissacarídeos/química , Staphylococcus aureus/efeitos dos fármacos
16.
Food Chem ; 300: 125171, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31330369

RESUMO

This study aimed to examine the modification effect of whey protein concentrate (WPC), WPC-gum arabic (WPC-GA) or WPC-high methoxyl pectin (WPC-PEC) complex to tailor-modify W/O/W emulsion for secondary microencapsulation of hydrophilic arbutin and hydrophobic coumaric acid. The stability and rheological properties of coated emulsions, encapsulation yield, release and degradation kinetics of arbutin and coumaric acid were investigated. Results revealed that WPC-PEC complex (at the ratio of 1:3) coating W/O/W emulsion exhibited the highest viscosity and stability, with the highest encapsulation yield of 91.08% for arbutin and 80.92% for coumaric acid, respectively. Tighter coating structure of the WPC-PEC complex (1:3) forming a stronger gel network structure was confirmed, accounting for the larger mean particle size of 569.67 nm. Moreover, the WPC-PEC (1:3) coating W/O/W emulsion also showed controlled release of arbutin and coumaric acid in simulated conditions. The k value of degradation kinetics for arbutin (7.99 × 10-4 at pH = 1.2, 4.19 × 10-4 at 90 °C and 7.52 × 10-4 at UV-C treatment) and coumaric acid (5.18 × 10-4 at pH = 1.2, 3.24 × 10-4 at 90 °C and 6.90 × 10-4 at UV-C treatment) indicated low degradation rate. The present study revealed that the WPC-PEC (1:3) coating W/O/W emulsion could provide a better synergistic effect on higher encapsulation yield and stability of arbutin and coumaric acid.


Assuntos
Arbutina/química , Cápsulas/química , Ácidos Cumáricos/química , Emulsões/química , Polissacarídeos/química , Arbutina/farmacocinética , Composição de Medicamentos , Goma Arábica/química , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Tamanho da Partícula , Pectinas/química , Reologia , Temperatura Ambiente , Raios Ultravioleta , Viscosidade , Proteínas do Soro do Leite/química
17.
Food Chem ; 300: 125217, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31351255

RESUMO

In this study, lecithin obtained from acid degumming of canola oil was fractionated with absolute ethanol. The lipid composition and emulsifying properties of the resulting fractions were investigated. The results showed that phosphatidylcholine and lyso-phosphatidylcholine were greatly enriched in the ethanol soluble fraction (ESF), accounting for 43.79% and 13.21% of ESF, respectively. Phosphatidylinositol, lyso-phosphatidylinositol and phosphatidic acid, as a group, were enriched in the ethanol insoluble fraction (EIF), accounting for 37.4% of EIF. ESF and EIF promoted oil/water (o/w) emulsions as stable as the parent canola lecithin. EIF was not better than the parent lecithin as w/o emulsifier. This information is critical for evaluating the potential utilization of these canola lecithin fractions as emulsifiers or sources of specific phospholipid.


Assuntos
Emulsificantes/química , Lecitinas/química , Fosfolipídeos/química , Óleo de Brassica napus/química , Fracionamento Químico , Emulsões/química , Etanol/química , Fosfatidilinositóis/química
18.
Food Chem ; 300: 125219, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31351259

RESUMO

Although storage temperature is important for partial coalescence, the literature is scant on exploring the partial coalescence behavior between refrigerated and room temperature storage. In this study, comparison of the partial coalescence behavior between 4 and 20 °C was investigated towards corresponding oil-in-water emulsions, and subsequently towards the ultimate properties of the aerated colloidal system. As expected, compared to the value of Avrami constant (K) at 20 °C, the value of palm kernel stearin (PKS85) and mixtures of PKS85 and glycerol monostearate (PKS85-GMS) obtained at 4 °C increased by 22 and 14 times, respectively. PKS85 and PKS85-GMS displayed the needlelike appearance (N-type crystal) with a little layer crystal (L-type crystal) at 4 °C and spherical shape formed by L-type crystal along with granular crystal at 20 °C. Interestingly, several unstable air bubbles with irregularly-shape were observed in the aerated emulsions at 20 °C, while these emulsions at 4 °C displayed numerous rounded and uniform air bubbles with glossy surface. This was attributed to the sufficient stiff needle crystals at 4 °C, facilitating the coalescence of fat globules via liquid fat bridges, further forming a rigid crystal-based network and trapping the air bubbles. Therefore, our findings gained an insight into the partial coalescence behavior in emulsion, providing theoretical support for designing and optimizing the production process of foam structure products.


Assuntos
Emulsões/química , Armazenamento de Alimentos/métodos , Ar , Cristalização , Óleo de Palmeira/química , Ácidos Esteáricos/química , Temperatura Ambiente , Água/química
19.
J Agric Food Chem ; 67(34): 9601-9610, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31334648

RESUMO

The influence of sucrose palmitate, Tween 20, and lecithin on the properties of heat-induced aggregates and cold-set gels of ß-lactoglobulin was studied based on an experimental mixture design with a fixed total emulsifier concentration. Emulsifiers were added to the protein solution before heating. Aggregate size and absolute values of ζ potential increased with the addition of emulsifiers, among which lecithin had the most pronounced effect. The water retention of the aggregates correlated positively with the aggregate size. Gels had reduced fracture stress and strains with increasing sucrose palmitate and decreasing Tween 20 contents. The fracture properties correlated with the ζ potentials of the aggregates, and larger aggregates led to gels with higher water-holding capacities. The emulsifiers hence influenced the gel properties indirectly via the aggregate properties. The impact of emulsifiers on food structures should therefore be considered when a food product is designed.


Assuntos
Emulsificantes/química , Lactoglobulinas/química , Lecitinas/química , Polissorbatos/química , Sacarose/análogos & derivados , Emulsões/química , Géis/química , Temperatura Alta , Agregados Proteicos , Sacarose/química , Viscosidade
20.
Int J Nanomedicine ; 14: 4697-4708, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31303754

RESUMO

Introduction and aim: Chlorhexidine Hydrochloride [Chx.HCl] has a broad-spectrum antibacterial effect, sustained action and low toxicity so it has been recommended as a potential root canal irrigant. The aim of this study was to improve the penetration ability, cleansing and antibacterial effect of Chx.HCl using a newly formulated Chx.HCl nanoemulsion and use it as root canal irrigant. Methods: Chx.HCl nanoemulsions were prepared using two different oils; Oleic acid and Labrafil M1944CS, two surfactants; Tween 20 and Tween 80 and co-surfactant; Propylene Glycol. Pseudoternary phase diagrams were constructed to designate the optimum systems. The prepared nanoemulsion formulae were evaluated for their drug content, emulsification time, dispersibility, droplet size, in-vitro drug release, thermodynamic stability, In-vitro antibacterial activity and ex-vivo study for the selected formula. Comparisons were made of Chx.HCl nanoemulsion with two different concentrations 0.75% and 1.6% vs Chx.HCl normal particle size as root canal irrigant for their penetration ability, cleansing effect and antibacterial effect. Results: The selected formula was F6 with composition of 2% Labrafil, 12% Tween 80 and 6% Propylene glycol. It has small particle size (12.18 nm), short emulsification time (1.67 seconds), and fast dissolution rate after 2 minutes. It was found to be a thermodynamically/physically stable system. The higher concentration of Chx.HClnanoemulsion1.6% shows the best penetration ability compared to Chx.HCl normal particle size due to the smaller particle size. Chx.HCl nanoemulsion 1.6% has the lowest mean value of the remaining debris surface area (2001.47 µm2) when compared to normal particle size material (2609.56 µm2). Conclusion: Chx.HCl nanoemulsion preparation has better cleansing ability and antibacterial effect with high efficacy on Enterococcus faecalis, where high reduction rate or complete eradication of bacterial cells has been achieved.


Assuntos
Antibacterianos/farmacologia , Clorexidina/farmacologia , Emulsões/química , Nanopartículas/química , Irrigantes do Canal Radicular/farmacologia , Contagem de Colônia Microbiana , Composição de Medicamentos , Liberação Controlada de Fármacos , Enterococcus faecalis/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Nanopartículas/ultraestrutura , Transição de Fase , Termodinâmica
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