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1.
Ultrason Sonochem ; 95: 106354, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36898248

RESUMO

The study aimed to evaluate the effect of ultrasonic pretreatment on the transesterification of lard with glycerol monolaurate (GML) using Lipozyme TL IM to synthesize diacylglycerol (DAG), and the physicochemical properties of lard, GML, ultrasonic-treated diacylglycerol (named U-DAG), purified ultrasonic-treated diacylglycerol obtained by molecular distillation (named P-U-DAG), and without ultrasonic-treated diacylglycerol (named N-U-DAG) were analyzed. The optimized ultrasonic pretreatment conditions were: lard to GML mole ratio 3:1, enzyme dosage 6 %, ultrasonic temperature 80 °C, time 9 min, power 315 W. After ultrasonic pretreatment, the mixtures reacted for 4 h in a water bath at 60 °C, the content of DAG reached 40.59 %. No significant variations were observed between U-DAG and N-U-DAG in fatty acids compositions and iodine value, while P-U-DAG had lower unsaturated fatty acids than U-DAG. Differential scanning calorimetry analysis showed that the melting and crystallization properties of DAGs prepared by ultrasonic pretreatment significantly differed from lard. FTIR spectra noted transesterification reaction from lard and GML with and without ultrasonic pretreatment would not change the structure of lard. However, thermogravimetric analysis proved that N-U-DAG, U-DAG, and P-U-DAG had lower oxidation stability than lard. The higher the content of DAG, the faster the oxidation speed.


Assuntos
Gorduras na Dieta , Diglicerídeos , Diglicerídeos/química , Gorduras na Dieta/análise , Catálise , Glicerol/química
2.
J Sci Food Agric ; 103(1): 108-117, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35810339

RESUMO

BACKGROUND: Diacylglycerol (DAG)-enriched oil has been attracting attention because of its nutritional benefits and biological functions, although the composition of its various free fatty acids (FFAs) and an unclear relationship between substrate and yield make it difficult to be identified and qualified with respect to its production. In the present study, linoleic acid-enriched diacylglycerol (LA-DAG) was synthesized and enriched from Camellia oil by the esterification process using the combi-lipase Lipozyme TL IM/RM IM system. RESULTS: The relationship between FFA composition and DAG species productivity was revealed. The results showed that heterogeneous FFA with a major constituent (more than 50%) exhibited higher DAG productivity and inhibited triacylglycerol productivity compared to homogeneous constituents. Joint characterization by high-performance liquid chromatography-evaporative light scattering detection, gas chromatography-mass spectrometry and ultra-performance liquid chromatography-heated electrospray ionization-tandem mass spectrometry identified that DAG components contained dilinoleic acid acyl glyceride, linoleyl-oleyl glyceride and dioleic acid acyl glyceride in esterification products. Under the optimum conditions, 60.4% 1,3-DAG and 61.3% LA-DAG in the crude product at 1 h reaction were obtained, and further purified to 81.7% LA-DAG and 94.7% DAG via silica column chromatography. CONCLUSION: The present study provides a guideline for the identification of DAG species, as well as a structure-guided preparation method of DAG-enriched oils via the cost-effective combi-lipase. © 2022 Society of Chemical Industry.


Assuntos
Camellia , Diglicerídeos , Diglicerídeos/química , Ácido Linoleico , Lipase/química , Óleos de Plantas/química , Glicerídeos , Ácidos Graxos não Esterificados
3.
Food Chem ; 391: 133201, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-35609461

RESUMO

This study developed an alpha-linolenic acid (ALA) supplement with emulsion form using ALA-rich diacylglycerol (ALA-DAG) and ALA-DAG stearin (DAG-SF) as a new source of ALA and emulsifier. Stable, commercial surfactant-free W/O emulsions with 90 wt% oil phase (including DAG-SF and ALA-DAG with 10:90 - 20:80 wt ratio) was fabricated. Microstructure and Raman spectra revealed that the compact crystal networks and high amounts of solid acyl chains were responsible for high emulsion stability. These emulsions exhibited good potential in improving the ALA nutritional status (with ALA release level of 60.49% - 62.98%). Furthermore, the emulsifier-to-oil ratio greatly impacted the emulsion texture (solid-like or liquid-like) and emulsions showed great oxidation stability (2.80 - 3.09 meq/kg lipid of peroxide value at 6th week). The tunable texture and high oxidation stability make this emulsion system useful for a wide range of food products. This developed emulsion system could provide valuable information for other important fatty acids supplement.


Assuntos
Diglicerídeos , Ácido alfa-Linolênico , Digestão , Diglicerídeos/química , Emulsificantes , Emulsões/química , Água/química
4.
Molecules ; 26(11)2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34072180

RESUMO

Herein, we prepared 1,3-dipalmitoyl-2-oleoyl glycerol (POP)-rich fats with reduced levels of diacylglycerols (DAGs), adversely affecting the tempering of chocolate, via two-step hexane fractionation of palm stearin. DAG content in the as-prepared fats was lower than that in POP-rich fats obtained by previously reported conventional two-step acetone fractionation. Cocoa butter equivalents (CBEs) were fabricated by blending the as-prepared fats with 1,3-distearoyl-2-oleoyl glycerol (SOS)-rich fats obtained by hexane fractionation of degummed shea butter. POP-rich fats achieved under the best conditions for the fractionation of palm stearin had a significantly lower DAG content (1.6 w/w%) than that in the counterpart (4.6 w/w%) prepared by the previously reported method. The CBEs fabricated by blending the POP- and SOS-rich fats in a weight ratio of 40:60 contained 63.7 w/w% total symmetric monounsaturated triacylglycerols, including 22.0 w/w% POP, 8.6 w/w% palmitoyl-2-oleoyl-3-stearoyl-rac-glycerol, 33.1 w/w% SOS, and 1.3 w/w% DAGs, which was not substantially different from the DAG content in cocoa butter (1.1 w/w%). Based on the solid-fat content results, it was concluded that, when these CBEs were used for chocolate manufacture, they blended with cocoa butter at levels up to 40 w/w%, without distinctively altering the hardness and melting behavior of cocoa butter.


Assuntos
Gorduras na Dieta/metabolismo , Diglicerídeos/química , Hexanos/química , Óleo de Palmeira/química , Cacau/química , Varredura Diferencial de Calorimetria , Cromatografia Líquida de Alta Pressão , Ácidos Graxos/química , Glicerol/química , Óleos de Plantas/química , Temperatura , Triglicerídeos/química
5.
Food Chem ; 327: 127014, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32434126

RESUMO

The influence of diacylglycerol (DAG) combined with polyglycerol polyricinoleate (PGPR) on the stability of water-in-oil (W/O) emulsions containing hydrogenated palm oil (HPO) was studied. Polarized light microscope revealed that DAG promoted HPO to crystallize at the water-oil interface, providing the combination of Pickering and network stabilization effects. It was proposed that the molecular compatibility of fatty acids in DAG with HPO accounted for the promotional effect. The interfacial crystallization of DAG together with the surface activity of PGPR led to the formation of emulsions with uniform small droplets and high freeze-thaw stability. Further exploration of physical properties indicated that the combination of DAG and PGPR dramatically improved the emulsion's viscoelasticity and obtained a larger deformation yield. Water droplets in DAG-based emulsions acted as active fillers to improve the network rigidity. Therefore, DAG is a promising material to be used as emulsifier to enhance the physical stability of W/O emulsions.


Assuntos
Diglicerídeos/química , Emulsões/química , Cristalização , Congelamento , Glicerol/análogos & derivados , Glicerol/química , Óleo de Palmeira/química , Óleo de Brassica napus/química , Ácidos Ricinoleicos/química , Viscosidade , Água/química
6.
Appl Biochem Biotechnol ; 191(3): 905-920, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31919758

RESUMO

The time course study of high monoester mixtures from soybean oil (HMMS) synthesis, as healthier alternatives to trans food products, in a supercritical CO2 (SCCO2) medium with and without enzyme, was investigated. Phosphorous nuclear magnetic resonance (31P-NMR) was used to quantify the absolute amount of partially esterified acylglycerols (PEGs). Carbon NMR was utilized to determine the type and position of the fatty acids (FAs) of HMMS. Enzyme and time significantly influenced the synthesis of 1-monoglycerides (1-MGs), 2-MGs, and 1,2-diglycerides (1,2-DGs) in this alcoholysis of soybean oil with 1,2-propanediol, based on high catalytic activity and operational stability of Novozym 435 in SCCO2 during short reaction time. Results suggest that 4 h is a suitable reaction time for this lipase-catalyzed interesterification (LIE) system for the synthesis of 2-MGs with a yield of 20%. The highest polyunsaturated fatty acid (PUFA) (65%) in the triglyceride (TG) of HMMS was produced after 4 h of reaction. After 6 h of reaction, a high level (20%) of saturated fatty acids (SFAs) was found in the TGs of HMMS, which were distributed between the sn-2 (5%) and sn-1, 3 (15%) positions.


Assuntos
Dióxido de Carbono/química , Propilenoglicol/química , Óleo de Soja/química , Catálise , Diglicerídeos/química , Enzimas Imobilizadas/química , Esterificação , Ácidos Graxos/química , Ácidos Graxos Insaturados/química , Proteínas Fúngicas , Gases , Glicóis/química , Microbiologia Industrial , Lipase/química , Espectroscopia de Ressonância Magnética , Monoglicerídeos/química , Triglicerídeos/química
7.
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 de Plantas/química , Biocatálise , Emulsificantes/química , Emulsões/química , Lipase/química , Oxirredução , Tamanho da Partícula , Polissorbatos/química , Água/análise , Proteínas do Soro do Leite/química
8.
Food Chem ; 311: 126017, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31864184

RESUMO

Phospholipid gum mesostructures formed in crude soybean oil after water degumming (WD) and enzymatic degumming (ED) were studied at a range of phospholipid and water concentrations. For ED, phospholipase C (PLC), phospholipase A2 (PLA2) and a mixture of phospholipases Purifine 3G (3G) were used. Both WD and ED resulted in lamellar liquid-crystalline phases, however, of different topology. The dependence of the bilayer spacings (as observed by SANS and SAXS) on the ratio between amount of water and amphiphilic lipids differed for WD and PLA2 ED vs PLC and 3G ED. This difference was also observed for dynamics at molecular scale as observed by time-domain (TD) NMR and attributed to partial incorporation of diglycerides and free fatty acids into gum bilayers after PLC and 3G ED. Feasibility of using TD-NMR relaxometry for quantification of the gum phase and estimation of degumming efficiency was demonstrated.


Assuntos
Manipulação de Alimentos/métodos , Glycine max/química , Fosfolipases/metabolismo , Fosfolipídeos/química , Gomas Vegetais/química , Água/química , Diglicerídeos/química , Ácidos Graxos/química , Cristais Líquidos , Espectroscopia de Ressonância Magnética , Espalhamento a Baixo Ângulo , Óleo de Soja/química , Difração de Raios X
9.
J Sci Food Agric ; 99(12): 5358-5367, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31056745

RESUMO

BACKGROUND: An adaptive neuro-fuzzy inference system (ANFIS) was employed to predict the oxidative stability of virgin olive oil (VOO) during storage as a function of time, storage temperature, total polyphenol, α-tocopherol, fatty acid profile, ultraviolet (UV) extinction coefficient (K268 ), and diacylglycerols (DAGs). RESULTS: The mean total quantities of polyphenols and DAGs were 1.1 and 1.9 times lower in VOOs stored at 25 °C than in the initial samples, and the mean total quantities of polyphenols and DAGs were 1.3 and 2.26 times lower in VOOs stored at 37 °C than in the initial samples, respectively. In a single sample, α-tocopherol was reduced by between 0.52 and 0.91 times during storage, regardless of the storage temperature. The mean specific UV extinction coefficients (K268 ) for VOO stored at 25 and 37 °C were reported as 0.15 (ranging between 0.06-0.39) and 0.13 (ranging between 0.06-0.35), respectively. The ANFIS model created a multi-dimensional correlation function, which used compositional variables and environmental conditions to assess the quality of VOO. The ANFIS model, with a generalized bell-shaped membership function and a hybrid learning algorithm (R2  = 0.98; MSE = 0.0001), provided more precise predictions than other algorithms. CONCLUSION: Minor constituents were found to be the most important factors influencing the preservation status and freshness of VOO during storage. Relative changes (increases and reductions) in DAGs were good indicators of oil oxidative stability. The observed effectiveness of ANFIS for modeling oxidative stability parameters confirmed its potential use as a supplemental tool in the predictive quality assessment of VOO. © 2019 Society of Chemical Industry.


Assuntos
Modelos Teóricos , Azeite de Oliva/química , Diglicerídeos/química , Ácidos Graxos/química , Armazenamento de Alimentos , Oxirredução , Polifenóis/química , Temperatura , alfa-Tocoferol/química
10.
Eur J Pharm Sci ; 135: 51-59, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31071439

RESUMO

Nanostructured lipid carriers (NLC) belong to youngest lipid-based nanocarrier class and they have gained increasing attention over the last ten years. NLCs are composed of a mixture of solid and liquid lipids, which solubilizes the active pharmaceutical ingredient, stabilized by a surfactant. The miscibility of the lipid excipients and structural changes (polymorphism) play an important role in the stability of the formulation and are not easily predicted in the early pharmaceutical development. Even when the excipients are macroscopically miscible, microscopic heterogeneities can result in phase separation during storage, which is only detected after several months of stability studies. In this sense, this work aimed to evaluate the miscibility and the presence of polymorphism in lipid mixtures containing synthetic (cetyl palmitate, Capryol 90®, Dhaykol 6040 LW®, Precirol ATO5® and myristyl myristate) and natural (beeswax, cocoa and shea butters, copaiba, sweet almond, sesame and coconut oils) excipients using Raman mapping and multivariate curve resolution - alternating least squares (MCR-ALS) method. The results were correlated to the macroscopic stability of the formulations. Chemical maps constructed for each excipient allowed the direct comparison among formulations, using standard deviation of the histograms and the Distributional Homogeneity Index (DHI). Lipid mixtures of cetyl palmitate/Capryol®; cetyl palmitate/Dhaykol®; myristyl myristate/Dhaykol® and myristyl myristate/coconut oil presented a single histogram distribution and were stable. The sample with Precirol®/Capryol® was not stable, although the histogram distribution was narrower than the samples with cetyl palmitate, indicating that miscibility was not the factor responsible for the instability. Structural changes before and after melting were identified for cocoa butter and shea butter, but not in the beeswax. Beeswax + copaiba oil sample was very homogenous, without polymorphism and stable over 6 months. Shea butter was also homogeneous and, in spite of the polymorphism, was stable. Formulations with cocoa butter presented a wider histogram distribution and were unstable. This paper showed that, besides the miscibility evaluation, Raman imaging could also identify the polymorphism of the lipids, two major issues in lipid-based formulation development that could help guide the developer understand the stability of the NLC formulations.


Assuntos
Portadores de Fármacos/química , Lipídeos/química , Nanopartículas/química , Diglicerídeos/química , Composição de Medicamentos , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Excipientes/química , Análise Multivariada , Miristatos/química , Palmitatos/química , Tamanho da Partícula , Óleos de Plantas/química , Polímeros/química , Propilenoglicóis/química , Solubilidade , Análise Espectral Raman , Tensoativos/química , Ceras/química
11.
Food Res Int ; 120: 504-513, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31000265

RESUMO

Diacylglycerols (DAGs) are interesting oil structuring molecules as they are structurally similar to triacylglycerols (TAGs), but are metabolized differently which results in weight loss and improved blood cholesterol levels upon dietary replacement of TAGs with DAGs. Many commercial products consist of a mixture of monoacylglycerols (MAGs) and DAGs, yet the effect of MAGs on the crystallization behavior of DAGs is still to be unraveled. Two types of commercial MAGs, one originating from hydrogenated palm stearin and one of hydrogenated rapeseed oil, were added in concentrations 1, 2 and 4% to 20% DAGs derived from hydrogenated soybean oil. Using differential scanning calorimetry, it was shown that the presence of MAGs delayed the onset of DAG crystallization. Rheological analysis revealed that MAGs also hindered crystal network development. Synchrotron X-ray diffraction analysis demonstrated that the addition of MAGs suppressed the formation of the ß form and stimulated the development of the ß' form. Likely, MAGs mainly hindered the crystallization of 1,3-DAGs, which are responsible for the development of the ß form, and stimulated the crystallization of the 1,2-DAGs, which can crystallize in the α and ß' forms. The presence of two polymorphic forms resulted in a decrease of the crystal network strength, as was derived from oscillatory rheological measurements. This research implies a different effect of monoacylglycerols on both the nucleation and crystal growth of 1,2- and 1,3-DAG isomers. This insight is not only relevant for oleogelation research, but also for emulsifying agents which often contain blends of MAGs, 1,2-DAGs and 1,3-DAGs.


Assuntos
Cristalização , Diglicerídeos/química , Monoglicerídeos/química , Óleos de Plantas/química , Varredura Diferencial de Calorimetria , Reologia , Difração de Raios X
12.
Anal Chem ; 91(8): 5021-5027, 2019 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-30896930

RESUMO

Lipids are a major class of molecules that play key roles in different biological processes. Understanding their biological roles and mechanisms remains analytically challenging due to their high isomeric content (e.g., varying acyl chain positions and/or double bond locations/geometries) in eukaryotic cells. In the present work, a combination of liquid chromatography (LC) followed by high resolution trapped ion mobility spectrometry-mass spectrometry (TIMS-MS) was used to investigate common isomeric glycerophosphocholine (PC) and diacylglycerol (DG) lipid species from human plasma. The LC dimension was effective for the separation of isomeric lipid species presenting distinct double bond locations or geometries but was not able to differentiate lipid isomers with distinct acyl chain positions. High resolution TIMS-MS resulted in the identification of lipid isomers that differ in the double bond locations/geometries as well as in the position of the acyl chain with resolving power ( R) up to ∼410 ( R ∼ 320 needed on average). Extremely small structural differences exhibiting collision cross sections (CCS) of less than 1% (down to 0.2%) are sufficient for the discrimination of the isomeric lipid species using TIMS-MS. The same level of performance was maintained in the complex biological mixture for the biologically relevant PC 16:0/18:1 lipid isomers. These results suggest several advantages of using complementary LC-TIMS-MS separations for regular lipidomic analysis, with the main emphasis in the elucidation of isomer-specific lipid biological activities.


Assuntos
Cromatografia Líquida , Diglicerídeos/química , Diglicerídeos/isolamento & purificação , Glicerilfosforilcolina/química , Glicerilfosforilcolina/isolamento & purificação , Espectrometria de Massas , Isomerismo
13.
J Agric Food Chem ; 67(9): 2700-2708, 2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30722664

RESUMO

3-Chloro-1,2-propanediol fatty acid esters (3-MCPD esters) are a group of process-induced contaminants that form during the refining and heating of fats and oils. In this study, a combined method of simulated deodorization and computational simulation was used to explore the precursor substance and the generation path of 3-MCPD esters. From the results, 3-MCPD esters reached a content level of 2.268 mg/kg when the diacylglyceride (DAG) content was 4% and temperature was 220 °C. A good correlation was observed between DAG and 3-MCPD ester contents ( y = 0.0612 x2 - 1.6376 x + 10.558 [ R2 = 0.958]). There were three pathways for the formation of 3-MCPD esters: (A) a direct nucleophilic substitution reaction, (B) an indirect nucleophilic substitution reaction, and (C) a mechanism of an intermediate (glycidyl ester) from the calculation of Gaussian software at the B3LYP/6-31+g** level. The data showed that the ester-based direct nucleophilic substitution reaction was the most likely reaction pathway. The energy barriers for the formation of the 3-MCPD esters dipalmitin, diolein, and dilinolein were 74.261, 66.017, and 59.856 kJ/mol, respectively, indicating that the formation process of 3-MCPD esters is a high-temperature endothermic process. Therefore, by controlling the introduction of precursor (DAG) and reducing the temperature, 3-MCPD ester formation was prevented.


Assuntos
Ésteres/química , Gorduras/química , Óleos de Plantas/química , alfa-Cloridrina/química , Diglicerídeos/análise , Diglicerídeos/química , Ésteres/análise , Tecnologia de Alimentos/métodos , Temperatura Alta , alfa-Cloridrina/análise
14.
J Microencapsul ; 36(1): 32-42, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30758259

RESUMO

Context: In this study, controlled ciprofloxacin (CIPRO) nanostrustructured lipid carriers of Precirol® ATO 5/Transcutol® HP (batch A) and tallow fat/Transcutol® HP (batch B) was carreid out. Objective: The aim was to improve solubility and bioavailability of CIPRO. Objective: Study of controlled ciprofloxacin (CIPRO) nanostructured lipid carriers of Precirol® ATO 5/Transcutol® HP (batch A) and tallow fat/Transcutol® HP (batch B). Methods: CIPRO concentrations C1-5 (0.0, 0.2, 0.5, 0.8, and 1.0% w/w) as AC1-5 and BC1-5 were prepared by hot homogenisation and characterised by zetasizer, differential scanning calorimetry, Fourier transform infra-red spectroscopy, in vitro drug release and growth inhibitory zone diameter (IZD) on agar-seeded Bacillus subtilis. Results: AC5 achieved polydispersed particles of ∼605 nm, 92% encapsulation efficiency (EE) and -28 mV similar to BC5 (∼789 nm, 91% EE, and -31 mV). Crystallinity indices (AC5 and BC5) were low at 3 and 5%, respectively. CIPRO release in AC5 was ∼98% in SGF (pH 1.2) and BC5 similarly ∼98% in SIF (pH 6.8). Conclusions: AC5 had superior growth inhibition of B. subtilis at lower concentration (1.2 µg/mL) than BC5 and CIPRO controls; hence could serve as possible sustained delivery system of CIPRO.


Assuntos
Antibacterianos/administração & dosagem , Bacillus subtilis/efeitos dos fármacos , Ciprofloxacina/administração & dosagem , Diglicerídeos/química , Portadores de Fármacos/química , Etilenoglicóis/química , Antibacterianos/química , Antibacterianos/farmacologia , Ciprofloxacina/química , Ciprofloxacina/farmacologia , Liberação Controlada de Fármacos , Nanoestruturas/química , Solubilidade
15.
SLAS Discov ; 24(6): 682-692, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30802416

RESUMO

Intramolecular CFP-YFP fluorescence resonance energy transfer (FRET) sensors expressed in cells are powerful research tools but have seen relatively little use in screening. We exploited the discovery that the expression of a CFP-YFP FRET diacylglycerol sensor (DAGR) increases over time when cells are incubated at room temperature to assess requirements for robust measurements using a Molecular Devices Spectramax i3x fluorescence plate reader. Expression levels resulting in YFP fluorescence >10-fold higher than untransfected cells and phorbol ester-stimulated FRET ratio changes of 60% or more were required to consistently give robust Z' > 0.5. As a means of confirming that these conditions are suitable for screening, we developed a novel multiple-read protocol to assay the NCI's Mechanistic Set III for agonists and antagonists of C1 domain activation. Sixteen compounds prevented C1 domain translocation. However, none blocked phorbol ester-stimulated protein kinase C (PKC) activity assessed using a phospho-specific antibody-six actually stimulated PKC activity. Cytometry, which produces higher Z' for a given FRET ratio change, might have been a better approach for discovering antagonists, as it would have allowed lower phorbol ester concentrations to be used. We conclude that CFP-YFP FRET measured in a Spectramax i3x plate reader can be used for screening under the conditions we defined. Our strategy of varying expression level and FRET ratio could be useful to others for determining conditions needed for robust cell-based intramolecular CFP-YFP FRET measurements on their instrumentation.


Assuntos
Técnicas Biossensoriais , Diglicerídeos/química , Descoberta de Drogas/métodos , Proteínas Luminescentes/química , Proteínas Luminescentes/genética , Domínios e Motivos de Interação entre Proteínas/efeitos dos fármacos , Biomarcadores , Linhagem Celular Tumoral , Avaliação Pré-Clínica de Medicamentos/métodos , Citometria de Fluxo , Transferência Ressonante de Energia de Fluorescência/métodos , Humanos , Imuno-Histoquímica , Microscopia de Fluorescência
16.
Food Chem ; 272: 12-17, 2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30309521

RESUMO

Deterioration of frying oil greatly affects the nutrition of fried foods. In this study, influence of fried food and oil type on the distribution of polar compounds in oils at total polar compound (TPC) of 24%, 25% and 27% was evaluated. Both food and oil significantly affected the composition of frying oil (P < 0.01) and the effect of oil was relatively more significant than that of food. Five groups of polar compounds were presented: triglyceride oligomer (TGO), triglyceride dimer (TGD), oxidized triglyceride monomer (oxTGM), diglyceride (DG) and free fatty acid (FFA). TGD and DG had the highest contents, up to 6.9%-7.5% and 8.1%-8.9% respectively, while FFA had the lowest content with 1.4%-1.7%. The compound of the greatest concern in frying oil, oxTGM, varied from 4.6% to 4.8%, when TPC reached 24%-27%. Data will be expected to provide the evidence for toxicological evaluation of fried oils and foods in restaurants.


Assuntos
Culinária , Análise de Alimentos , Óleos de Plantas/química , Cromatografia Gasosa , Diglicerídeos/análise , Diglicerídeos/química , Ácidos Graxos não Esterificados/análise , Ácidos Graxos não Esterificados/química , Óleo de Palmeira/química , Óleos de Plantas/análise , Óleo de Brassica napus/química , Óleo de Girassol/química , Triglicerídeos/análise , Triglicerídeos/química
17.
Food Res Int ; 105: 423-431, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29433232

RESUMO

PKO and CNO are composed of 97-98% triacylglycerols and 2-3% minor non-triglyceride components (FFA, DAG and MAG). Triglycerides were separated from minor components by chromatographic method. The lipid composition, thermal properties, polymorphism, isothermal crystallization behavior, nanostructure and microstructure of PKO, PKO-TAG, CNO and CNO-TAG were evaluated. Removal of minor components had no effect on lipid composition and equilibrium solid fat contents. However, presence of minor components did increase the slip melting point and promoted the onset of crystallization from DSC crystallization profiles. The thickness of the nanoscale crystals increased with no polymorphic transformation after removing the minor components. Crystallization kinetics revealed that minor components decreased crystal growth rate with higher t1/2. Sharp changes in the values of the Avrami constant k and exponent n were observed for all fats around 10°C. Increases in n around 10°C indicated a change from one-dimensional to multi-dimensional growth. From the results of polarized light micrographs, the transformation from the coarser crystal structure to tiny crystal structure occurred in microstructure networks at the action of minor components.


Assuntos
Óleo de Coco/química , Manipulação de Alimentos/métodos , Óleos de Plantas/química , Cristalização , Diglicerídeos/química , Ácidos Graxos não Esterificados/química , Cinética , Modelos Químicos , Monoglicerídeos/química , Nanopartículas , Óleo de Palmeira , Temperatura de Transição , Triglicerídeos/química
18.
Food Chem ; 248: 210-216, 2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29329846

RESUMO

An enzymatic process was developed for the preparation of a nutritionally enriched 1,3-diacylglycerol(DAG)-rich oil from a blend of refined sunflower and rice bran oils. The process involves hydrolysis of vegetable oil blend using Candida cylindracea followed by esterification with glycerol using Lipozyme RM1M. The resultant DAG-rich oil contains 84% of DAG (66% of 1,3-DAG, 18% of 1,2-DAG) and 16% of triacylglycerol (TAG) along with micro nutrients like γ-oryzanol, tocotrienols, tocopherols and phytosterols. Nutritional studies of the DAG-rich oil were conducted in Wistar rats and compared with sunflower oil (SFO). The calorific value of the DAG-rich oil was estimated to be 6.45 Kcals/g as against 9.25 Kcals/g for SFO. The serum and liver cholesterol and TAG levels in rats fed with 1,3-DAG-rich oil were found to be significantly reduced as compared to rats fed diet containing SFO. We conclude that 1,3-DAG-rich oil is a low calorie fat and exhibits hypolipidemic effects.


Assuntos
Diglicerídeos/química , Hipolipemiantes/química , Hipolipemiantes/farmacologia , Óleo de Farelo de Arroz/química , Óleo de Girassol/química , Animais , Restrição Calórica , Candida , Colesterol/sangue , Colesterol/metabolismo , Esterificação , Lipase/química , Lipase/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Fitosteróis/análise , Ratos , Ratos Wistar , Tocoferóis/análise , Triglicerídeos/análise , Triglicerídeos/metabolismo
19.
Drug Dev Ind Pharm ; 44(6): 895-901, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29254385

RESUMO

The objective of the study was to develop a self-microemulsifying drug delivery system (SMEDDS), also known as microemulsion preconcentrate, for oral delivery of five poorly water-soluble nutraceuticals or bioactive agents, namely, vitamin A, vitamin K2, coenzyme Q10, quercetin and trans-resveratrol. The SMEDDS contained a 1:1 mixture (w/w) of Capmul MCM NF (a medium chain monoglyceride) and Captex 355 EP/NF (a medium chain triglyceride) as the hydrophobic lipid and Tween 80 (polysorbate 80) as the hydrophilic surfactant. The lipid and surfactant were mixed at 50:50 w/w ratio. All three of the SMEDDS components have GRAS or safe food additive status. The solubility of nutraceuticals was determined in Capmul MCM, Captex 355, Tween 80, and the SMEDDS (microemulsion preconcentrate mixture). The solubility values of vitamin A palmitate, vitamin K2, coenzyme Q10, quercetin, and trans-resveratrol per g of SMEDDS were, respectively, 500, 12, 8, 56, and 87 mg. Appropriate formulations of nutraceuticals were prepared and filled into hard gelatin capsules. They were then subjected to in vitro dispersion testing using 250 mL of 0.01 N HCl in USP dissolution apparatus II. The dispersion test showed that all SMEDDS containing nutraceuticals dispersed spontaneously to form microemulsions after disintegration of capsule shells with globule size in the range of 25 to 200 nm. From all formulations, except that of vitamin K2, >80-90% nutraceuticals dispersed in 5-10 min and there was no precipitation of compounds during the test period of 120 min. Some variation in dispersion of vitamin K2 was observed due to the nature of the material used (vitamin K2 pre-adsorbed onto calcium phosphate). The present report provides a simple and organic cosolvent-free lipid-based SMEDDS for the oral delivery of poorly water-soluble nutraceuticals. Although a 50:50 w/w mixture of lipid to surfactant was used, the lipid content may be increased to 70:30 without compromising the formation of microemulsion.


Assuntos
Suplementos Nutricionais/normas , Diglicerídeos/administração & dosagem , Glicerídeos/química , Lipídeos/química , Monoglicerídeos/administração & dosagem , Polissorbatos/química , Tensoativos/química , Triglicerídeos/química , Diglicerídeos/química , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Monoglicerídeos/química , Polissorbatos/administração & dosagem , Solubilidade , Água
20.
J Chromatogr A ; 1514: 80-87, 2017 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-28768579

RESUMO

Tiger nut (Cyperus esculentus L.) is a crop traditionally grown in Valencia Region (Spain) and other temperate and tropical regions in the world, where its tubers are commonly consumed as tiger nut milk (horchata). Because of their nutritive potential and original taste, these products are beginning to spread internationally and, as consequence, analytical procedures to assess nutritional profiles, quality control issues are acquiring increasing relevance. The main objective of this study was to use an advance analytical method and chemometrics tools to determine if the ultra-high temperature (UHT) treatment necessary to extend the shelf life of tiger nut milk would affect the profile of nutrients when compared to fresh product. A cold solvent extraction followed by liquid chromatography coupled with high resolution mass spectrometry (UHPLC-HRMS) was used. Datasets obtained from UHT and fresh tiger nut milk data were analyzed through an untargeted metabolomics approach to compare chemical patterns, highlighting differences in citric acid esters of mono- diglycerides (CITREM) and monoacylglycerol (MAG) used as emulsifiers of UHT products, and a remarkably higher abundance of biotin, phosphatidic acid (PA) and L-arginine in fresh products. These results showed that untargeted metabolomics through high resolution tandem mass spectrometry allowed fine differences between food products to be found, therefore, the nutrient lost caused by UHT treatment was clearly discerned.


Assuntos
Cyperus/metabolismo , Qualidade dos Alimentos , Metabolômica , Óleos de Plantas/análise , Aminoácidos/análise , Cromatografia Líquida de Alta Pressão , Análise por Conglomerados , Cyperus/química , Diglicerídeos/química , Emulsificantes/química , Ácidos Graxos/análise , Ácidos Graxos/química , Temperatura Alta , Monoglicerídeos/química , Óleos de Plantas/química , Óleos de Plantas/metabolismo , Análise de Componente Principal , Açúcares/análise , Açúcares/química , Espectrometria de Massas em Tandem , Vitaminas/análise
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