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1.
Mar Drugs ; 22(5)2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38786615

RESUMO

A predigested product from arachidonic acid oil (ARA) and docosahexaenoic acid (DHA) oil in a 2:1 (w/w) ratio has been developed and evaluated in an in vitro digestion model. To produce this predigested lipid mixture, first, the two oils were enzymatically hydrolyzed up to 90% of free fatty acids (FFAs) were achieved. Then, these two fatty acid (FA) mixtures were mixed in a 2:1 ARA-to-DHA ratio (w/w) and enzymatically esterified with glycerol to produce a mixture of FFAs, mono-, di-, and triacylglycerides. Different glycerol ratios and temperatures were evaluated. The best results were attained at 10 °C and a glycerol-to-FA molar ratio of 3:1. The bio-accessibility of this predigested mixture was studied in an in vitro digestion model. A total of 90% of the digestion product was found in the micellar phase, which contained 30% monoacylglycerides, more than 50% FFAs, and a very small amount of triacylglycerols (3% w/w). All these data indicate an excellent bio-accessibility of this predigested mixture.


Assuntos
Ácido Araquidônico , Digestão , Ácidos Docosa-Hexaenoicos , Ácidos Docosa-Hexaenoicos/química , Ácido Araquidônico/metabolismo , Glicerol/química , Temperatura , Hidrólise , Triglicerídeos/química , Animais , Ácidos Graxos não Esterificados/metabolismo , Ácidos Graxos não Esterificados/química , Humanos
2.
Molecules ; 28(19)2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37836796

RESUMO

An alternative olive oil (OO) production process has been developed based on the combination of olive dehydration, followed by extraction with an expeller press. This procedure eliminates the utilization of water and avoids the malaxation stage. Hence, no water residues are generated. In this study, the mentioned alternative methodology was compared to conventional extraction methods. High extraction yields and oil recovery were obtained with our novel procedure. On the contrary, substantial percentages of by-products were generated with conventional methodology. The quality indexes (acidity and peroxide values) of the oils obtained by the combination of dehydration and expeller (dOO) were 0.4% of oleic acid and 3 meq O2/kg of oil, respectively. Furthermore, none of the applied processes affected the resulting OO's fatty acid composition and lipid profile. Total phenolic content was up to four times higher for dOO than for other olive oils and it showed resistance to oxidation with an oxidative stability index about five times higher than that for conventional olive oils.


Assuntos
Desidratação , Olea , Azeite de Oliva/química , Olea/química , Antioxidantes , Ácidos Graxos , Óleos de Plantas/química
3.
Clin Nutr ESPEN ; 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39303783

RESUMO

BACKGROUND & AIMS: Maintaining an adequate supply of arachidonic acid (ARA) and docosahexaenoic acid (DHA) is essential for optimal growth of preterm infants. This study aims to evaluate and compare the digestibility and bioaccessibility of ARA and DHA oils compared to their predigested product through an in vitro digestion model. METHODS: An in vitro gastrointestinal digestion model was used in two stages: gastric digestion and intestinal digestion. Samples of two polyunsaturated rich oils (ARA and DHA oils) and their predigested product (2:1, ARA: DHA) produced by enzymatic glycerolysis have been digested for 120 minutes. The final digestion product obtained was composed of three phases: an upper oily phase (OP) containing the undigested species, an intermediate micellar phase (MP) containing digested and bioaccessible lipids, and a precipitate phase (PP) with insoluble compounds. The reaction was monitored by taking aliquots and their subsequent lipid extraction and analysis. RESULTS: Poorer digestibility for ARA and DHA oils was observed based on the percentage of the oily phase (26.7% and 20%, respectively) found compared to the glycerolysis product (GP) oily phase (13.9%). The highest micellar phase was found in the GP (approx. 83%). On the other hand, the monoglyceride (MAG) content was lower in the digestion product (DP) from ARA and DHA oils, 4.3% and 9.2%, respectively, compared to the MAG observed in the DP of GP (15%). CONCLUSION: Considering the percentage of oily phase, micellar phase, and the MAG content, it can be concluded that the GP is more digestible and ARA and DHA are more bioaccessible than in its precursor oils.

4.
Foods ; 13(17)2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39272562

RESUMO

Polyunsaturated fatty acids (PUFAs), especially arachidonic acid (ARA) and docosahexaenoic acid (DHA), are extremely important fatty acids for brain development in the fetus and early childhood. Premature infants face challenges obtaining these two fatty acids from their mothers. It has been reported that supplementation with triacylglycerols (TAGs) with an ARA:DHA (w/w) ratio of 2:1 may be optimal for preterm infants, as presented in commercial formulas such as Formulaid™. This study explored methods to produce TAGs with a 2:1 ratio (ARA:DHA), particularly at the more bioavailable sn-2 position of the glycerol backbone. Blending and enzymatic acidolysis of microalgae oil (rich in DHA) and ARA-rich oil yielded products with the desired ARA:DHA ratio, enhancing sn-2 composition compared to Formulaid™ (1.6 for blending and 2.3 for acidolysis versus 0.9 in Formulaid™). Optimal acidolysis conditions were 45 °C, a 1:3 substrate molar ratio, 10% Candida antarctica lipase, and 4 h. The process was reproducible, and scalable, and the lipase could be reused. In vitro digestion showed that 75.5% of the final product mixture was bio-accessible, comprising 19.1% monoacylglycerols, ~50% free fatty acids, 14.6% TAGs, and 10.1% diacylglycerols, indicating better bio-accessibility than precursor oils.

5.
Food Res Int ; 165: 112475, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36869488

RESUMO

Pomegranate seeds contain up to 20% oil with a high content of punicic acid (85%), which is responsible for several biological activities. In this work, two pomegranate oils obtained by a two-step sequential extraction, first with an expeller and then via supercritical CO2 technologies, have been studied in a static gastrointestinal in vitro digestion model to evaluate their bioaccessibility. The micellar phases obtained were evaluated by an in vitro model of intestinal inflammation and Caco-2 cells exposed to the inflammatory mediator lipopolysaccharide (LPS). Inflammatory response was assessed by measuring the production of interleukins IL-6 and IL-8, and tumor necrosis factor α (TNF-α), and by evaluating the monolayer integrity. The results obtained indicate that expeller pomegranate oil (EPO) provides the highest amount of micellar phase (ca. 93%) with free fatty acids and monoacylglycerols as major components. The micellar phase obtained with supercritical CO2 pomegranate oil (SCPO) is ca. 82% with similar lipid composition. Micellar phases of EPO and SCPO showed high stability and adequate particle size. EPO shows an anti-inflammatory response, reducing the production of IL-6, IL-8 and TNF-α in LPS stimulated caco-2 cells and increasing the integrity of the cell monolayer as measured by transepithelial electrical resistance (TEER). In the case of SCPO, the anti-inflammatory effect was only evident for IL-8. The present work demonstrates good digestibility, bioaccessibility and anti-inflammatory response of both EPO and SCPO oils.


Assuntos
Punica granatum , Humanos , Células CACO-2 , Dióxido de Carbono , Interleucina-6 , Interleucina-8 , Lipopolissacarídeos , Fator de Necrose Tumoral alfa , Frutas , Micelas , Anti-Inflamatórios , Digestão , Óleos de Plantas
6.
J Food Sci ; 87(7): 3268-3278, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35860984

RESUMO

Three strategic edible oils, that is, olive oil, microalgae oil, and shea butter, with a significantly different composition of fatty acids (FA), have been studied in a static in vitro digestion model to evaluate the rate of hydrolysis, bioaccessibility, and micellar phases formed in the process. Lipid composition of each phase and how the lipids are distributed in the different phases have been obtained using this in vitro digestion model. We demonstrate that the composition in FA and the physical properties of the oil are the key factors determining the distribution of lipids in the different phases. The fastest rate of hydrolysis was observed for olive oil and the highest triacylglycerol conversion was attained for shea butter. In contrast, the most abundant precipitate phase was obtained for shea butter, which also produces the highest co-crystallization of cholesterol among the three edible oils studied. This study reveals that digestibility of edible oils is directly related with the initial rate of hydrolysis.


Assuntos
Colesterol , Ácidos Graxos , Digestão , Azeite de Oliva , Óleos de Plantas/química , Triglicerídeos/química
7.
Food Chem ; 392: 133197, 2022 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-35659697

RESUMO

This study aimed to selectively enrich stearidonic acid (SDA) together with γ-linolenic acid (GLA) in Echium plantagineum oil by urea complexation. The complexation process at room temperature was carried out replacing common organic solvents, such as hexane and ethanol, by alternative compounds, included in Green Solvent and Food Grade categories, adapting this process towards the principles of Green Chemistry. This substitution was also intended to avoid the generation of the toxic compound ethyl carbamate. Among all the solvents studied, the mixture propionic acid and α-pinene provided the best results, leading to a final product comprised of ∼99% of PUFA, with ∼45% SDA (∼14% in the original oil), and without apparition of ethyl carbamate. The procedure was tested on other raw materials (salmon and microalgae oils). The solvent was efficiently recuperated from the liquid phase (∼87% recovery) and reutilized once with almost identical results.


Assuntos
Ácidos Graxos Ômega-3 , Uretana , Ácidos Graxos Ômega-3/química , Óleos de Plantas/química , Sementes/química , Solventes , Ureia/química , Uretana/análise
8.
BMJ Open ; 12(11): e063182, 2022 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-36450427

RESUMO

INTRODUCTION: Death following surgical procedures is a global health problem, accounting for 4.2 million deaths annually within the first 30 postoperative days. The fourth indicator of The Lancet Commission on Global Surgery is essential as it seeks to standardise postoperative mortality. Consequently, it helps identify the strengths and weaknesses of each country's healthcare system. Accurate information on this indicator is not available in Colombia, limiting the possibility of interventions applied to our population. We aim to describe the in-hospital perioperative mortality of the surgical procedures performed in Colombia. The data obtained will help formulate public policies, improving the quality of the surgical departments. METHODS AND ANALYSIS: An observational, analytical, multicentre prospective cohort study will be conducted throughout Colombia. Patients over 18 years of age who have undergone a surgical procedure, excluding radiological/endoscopic procedures, will be included. A sample size of 1353 patients has been projected to achieve significance in our primary objective; however, convenience sampling will be used, as we aim to include all possible patients. Data collection will be carried out prospectively for 1 week. Follow-up will continue until hospital discharge, death or a maximum of 30 inpatient days. The primary outcome is perioperative mortality. A descriptive analysis of the data will be performed, along with a case mix analysis of mortality by procedure-related, patient-related and hospital-related conditions ETHICS AND DISSEMINATION: The Fundación Cardioinfantil-Instituto de Cardiología Ethics Committee approved this study (No. 41-2021). The results are planned to be disseminated in three scenarios: the submission of an article for publication in a high-impact scientific journal and presentations at the Colombian Surgical Forum and the Congress of the American College of Surgeons. TRIAL REGISTRATION NUMBER: NCT05147623.


Assuntos
Estudos Prospectivos , Humanos , Adolescente , Adulto , Colômbia/epidemiologia , Tamanho da Amostra , Mortalidade Hospitalar , Resultado do Tratamento , Estudos Observacionais como Assunto , Estudos Multicêntricos como Assunto
9.
ACS Omega ; 6(16): 10578-10591, 2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-34056212

RESUMO

A new methodology has been developed for analyzing heat and mass transfer to predict wax deposition in crude oil pipelines using the law of the wall dimensionless parameters. A set of physically meaningful dimensionless groups and parameters has laid a strong foundation behind the proposed methodology. The paper presents a discussion regarding the development of scale-up correlations from laboratory scale to field scale, considering the combination of both analytical groups and empirical correlations. Data from previous literature studies were employed for determining realistic values for the developed parameters and scale-up correlations. The utilization of new dimensionless scale-up parameters indicated that the wax deposition in crude oil pipelines is independent of the Reynolds number and the inner diameter of the pipeline. It further indicates that wax deposition in crude oil pipelines is mainly dependent on the heat transfer process and not on the shear reduction process. The dimensionless technique developed here can be utilized for determining the optimum pipe size and pigging frequencies to reduce and mitigate the effect of the wax deposition process.

10.
Annu Rev Food Sci Technol ; 11: 319-337, 2020 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-31910657

RESUMO

In recent years, the use of green solvents in enzyme catalysis of lipophilic compounds is achieving increasing interest from different perspectives. Conducting reactions under supercritical fluids, ionic liquids, deep eutectic solvents, and other green solvents affords opportunities to overcome problems associated with the lack of solubility of lipids in conventional solvents and the poor miscibility of substrates. Research on the biocatalytic production of modified lipids in the framework of green chemistry is conducted to improve the efficiency of obtaining the desired products as well as the selectivity, stability, and activity of the enzymatic systems. This overview describes the fundamentals and characteristics of several types of green solvents, the main variables involved in enzymatic processes, and examples and applications in the field of lipid modification.


Assuntos
Lipídeos/química , Química Verde , Líquidos Iônicos/química , Solubilidade , Solventes/química
11.
Food Funct ; 11(1): 813-823, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31932815

RESUMO

This work studies the effect of enzymatic glycerolysis on digestibility and bioaccessibility of ratfish liver oil (RLO) rich in alkylglycerols (AKGs), as well as the capability of the glycerolysis product (GP) to act as lipid-based delivery system (LBDS) for a supercritical rosemary extract. For comparison purposes, digestibility and bioaccessibility of two additional lipid systems i.e. original RLO and RLO with addition of GRAS monoolein (MO) as emulsifier agent (RLO + MO), have been evaluated. We have studied the efficiency of the GP and RLO + MO lipid systems as LBDS by combining them with a supercritical rosemary extract (RE), i.e. RE lipid-based formulations. In vitro digestibility and bioaccessibility of un-loaded lipid systems, RE lipid-based formulations and un-carried RE have been determined. The results show a higher digestibility and bioaccessibility of the GP as compared to those of original RLO and RLO + MO. Likewise, a substantial improvement of RE bioaccessibility has been observed when GP is used as lipid carrier of RE. The present work demonstrates that enzymatic glycerolysis is an efficient strategy to obtain highly bioaccessible and potentially bioactive alkylglycerol-based delivery systems, which can be used to increase the bioaccessibility of low water-soluble bioactive compounds.


Assuntos
Digestão/efeitos dos fármacos , Extratos Vegetais/farmacologia , Rosmarinus , Disponibilidade Biológica , Sistemas de Liberação de Medicamentos , Emulsificantes/administração & dosagem , Humanos , Técnicas In Vitro , Extratos Vegetais/administração & dosagem
12.
Rev Peru Med Exp Salud Publica ; 37(3): 559-565, 2020 Dec 02.
Artigo em Espanhol | MEDLINE | ID: mdl-33295562

RESUMO

During the COVID-19 pandemic, a new, severe and unusual condition called Multisystem Inflammatory Syndrome in children emerged, from which there is still much to learn. We report 8 children admitted to Instituto Nacional de Salud del Niño, in Lima, Perú. Their mean age was 5,1 years. Their clinical presentation included fever, acute gastrointestinal symptoms, ocular and mucocutaneous involvement. Four patients met criteria for classic Kawasaki Disease. All the patients had positive serology for SARS-CoV-2, abnormal complete blood counts and coagulation tests, and elevated inflammatory markers. Five had elevated liver enzymes and three had kidney involvement. Four patients met criteria for Macrophage Activation Syndrome. All of them received intravenous immune globulin, corticosteroids and aspirin. No coronary aneurysms were identified. Only one developed miocarditis, shock and was admitted to the Pediatric Intensive Care Unit. Most patients recovered successfully. Every child with fever, gastrointestinal and dermatological symptoms, associated with prior exposure to SARS-CoV-2, should be investigated for multi-systemic compromise.


La pandemia de COVID-19 ha traído una nueva afección grave e inusual denominada Síndrome Inflamatorio Multisistémico en niños, de la cual aún hay mucho por conocer. Presentamos una serie de 8 casos atendidos en el Instituto Nacional de Salud del Niño, Lima Perú. La edad media fue 5,1 años. La presentación clínica incluyó fiebre, problemas gastrointestinales agudos, afectación ocular y mucocutánea. Cuatro cumplieron criterios para Enfermedad de Kawasaki clásica. Todos tuvieron serología positiva para SARS-CoV-2, hemograma patológico, marcadores inflamatorios elevados y pruebas de coagulación alteradas. Cinco casos presentaron hipertransaminasemia y tres retención nitrogenada. Cuatro casos cumplieron criterios para Síndrome de Activación Macrófagica. Todos recibieron inmunoglobulina intravenosa, corticoides y ácido acetil salicílico. Ninguno desarrolló aneurismas coronarios. Solo uno presentó miocarditis, shock y requirió ingreso a Unidad de Cuidados Intensivos. La mayoría evolucionaron favorablemente. En todo niño con fiebre, síntomas gastrointestinales y dermatológicos; asociado a exposición al SARS-CoV-2, debe investigarse compromiso multisistémico.


Assuntos
COVID-19/diagnóstico , Síndrome de Linfonodos Mucocutâneos/diagnóstico , SARS-CoV-2/imunologia , Síndrome de Resposta Inflamatória Sistêmica/diagnóstico , Corticosteroides/administração & dosagem , Anticorpos Antivirais/análise , COVID-19/sangue , Criança , Pré-Escolar , Feminino , Hospitais Pediátricos , Humanos , Imunoglobulina G/análise , Imunoglobulina M/análise , Imunoglobulinas Intravenosas/administração & dosagem , Fatores Imunológicos/administração & dosagem , Lactente , Síndrome de Ativação Macrofágica/diagnóstico , Masculino , Peru , Síndrome de Resposta Inflamatória Sistêmica/sangue , Síndrome de Resposta Inflamatória Sistêmica/tratamento farmacológico , Resultado do Tratamento , Tratamento Farmacológico da COVID-19
13.
Food Chem ; 290: 316-323, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31000052

RESUMO

The oxidative stability of Echium oil has been studied by two accelerated oxidation methodologies namely Rancimat and differential scanning calorimetry at selected temperatures in the range 50-110 °C. Kinetic analyses have provided Arrhenius parameters, oxidative stability indexes (OSI), temperature coefficients (tcoef), Q10 and OSI at 20 °C (OSI20) for both methodologies focussing on secondary and tertiary oxidation products. Peroxide, p-anisidine and polar compounds values have been measured to characterize from primary to tertiary oxidation products. In general, susceptibility of this oil to oxidation has been found to be larger than for other vegetable oils, according to the OSI20 values estimated by Rancimat and differential scanning calorimetry. However, the values of tcoeff and Q10 are found to be similar to those described for vegetable oils. In addition, a study of the influence of two antioxidants, namely hydroxytyrosol and rosemary extract on the oxidative stability of Echium oil has been carried out using both methodologies. Protective effects over oxidation by up to a threefold increase of OSI20 values have been found for both antioxidants at the highest dose utilized.


Assuntos
Echium/química , Álcool Feniletílico/análogos & derivados , Extratos Vegetais/química , Óleos de Plantas/química , Rosmarinus/química , Antioxidantes/química , Varredura Diferencial de Calorimetria , Echium/metabolismo , Entropia , Cinética , Oxirredução , Álcool Feniletílico/química , Rosmarinus/metabolismo , Temperatura
14.
Heliyon ; 5(11): e02718, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31768428

RESUMO

The determination of multiphase flow parameters such as flow pattern, pressure drop and liquid holdup, is a very challenging and valuable problem in chemical, oil and gas industries, especially during transportation. There are two main approaches to solve this problem in literature: data based algorithms and mechanistic models. Although data based methods may achieve better prediction accuracy, they fail to explain the two-phase characteristics (i.e. pressure gradient, holdup, gas and liquid local velocities, etc.). Recently, many approaches have been made for establishing a unified mechanistic model for steady-state two-phase flow to predict accurately the mentioned properties. This paper proposes a novel data-driven methodology for selecting closure relationships from the models included in the unified model. A decision tree based model is built based on a data driven methodology developed from a 27670 points data set and later tested for flow pattern prediction in a set made of 9224 observations. The closure relationship selection model achieved high accuracy in classifying flow regimes for a wide range of two-phase flow conditions. Intermittent flow registering the highest accuracy (86.32%) and annular flow the lowest (49.11%). The results show that less than 10% of global accuracy is lost compared to direct data based algorithms, which is explained by the worse performance presented for atypical values and zones close to boundaries between flow patterns.

15.
J Agric Food Chem ; 56(3): 1078-83, 2008 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-18167076

RESUMO

Ethanolysis of shark liver oil was carried out to generate a product enriched in nonesterified alkoxyglycerols and fatty acid ethyl esters. For the present study, the original oil contained very low amounts of squalene, and thus, unsaponifiable matter was mainly constituted by nonesterified alkoxyglycerols (NEAKG). A small percentage of monoesterified alkoxyglycerols (MEAKG) was also detected. Supercritical fluid extraction was employed to fractionate the mixture, achieving a complete elimination of esters and concentrating the alkoxyglycerol compounds in the raffinate product. Extractions were carried out in a countercurrent packed column, using extraction pressures in the range of 140-180 bar, temperatures from 45 to 65 degrees C, and a solvent-to-feed ratio of 15. NEAKG + MEAKG purity obtained in the raffinate at the best extraction conditions was around 78% w/w, and satisfactory yield (>60%) was also achieved. Therefore, the raffinate product can be re-esterified to design highly valuable ether lipid compounds.


Assuntos
Cromatografia com Fluido Supercrítico , Óleos de Peixe/química , Glicerol/isolamento & purificação , Fígado/química , Tubarões , Animais , Fracionamento Químico , Cromatografia com Fluido Supercrítico/instrumentação , Esterificação , Ácidos Graxos/isolamento & purificação
16.
J Oleo Sci ; 67(9): 1091-1099, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30175765

RESUMO

Concentration of polyunsaturated fatty acids ethyl esters (FAEE) by urea complexation from Echium oil was studied. Different variables involved in the process were investigated: amount and particle size of urea, solvent volume and ratio (hexane/ethanol), load of FAEE and reaction time. Hence, the main goal was to optimize SDA concentration (%) and yield (%) of stearidonic acid (SDA, 18:4 ω-3) and other bioactive FAEE. Similar behaviors were observed in fractionation between α-linolenic (ALA)-linoleic (LA), and γ-linolenic (GLA)-stearidonic (SDA) acids, attributed to similarities on their chemical structures, due to the position of the double bonds. At laboratory scale, the optimal conditions were 3 g urea (powder), 3.6 mL of hexane, 0.54 mL of ethanol and 800 mg of FAEE, during 20 h at 25°C. A scaling-up at pilot plant was carried out twice, obtaining more than 100 g of a final product, with ~29% SDA concentration and ~78% yield. Besides, after two washings with water, ethyl carbamates (urethanes) were not detected in the final product. Thus, a mixture of FAEE with about 85% of bioactive fatty acids with anti-inflammatory properties was obtained, which can be a high added-value product with great potential for the synthesis of functional lipids and nutraceuticals.


Assuntos
Echium/química , Ácidos Graxos Ômega-3/análise , Óleos de Plantas/química , Ureia/química , Anti-Inflamatórios , Ésteres/análise , Ésteres/química , Etanol/química , Ácidos Graxos Ômega-3/química , Ácidos Graxos Insaturados/análise , Ácidos Graxos Insaturados/química , Hexanos/química , Tamanho da Partícula , Solventes/química , Fatores de Tempo , Uretana , Água
17.
Food Funct ; 9(7): 4028-4035, 2018 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-29987279

RESUMO

Lipid-based delivery systems have been broadly utilized to enhance bioavailability and bioaccessibility properties of drugs. Loading capacity and drug stability within the lipid matrix is influenced by the phase behavior of the lipid components that make up the vehicle. In this study we have investigated the influence of thermal processing at 50 °C on the subsequent phase behavior of a lipid-based delivery system comprised of a blend of monoacylglycerols, diacylglycerols, monoalkylglycerols and dialkylglycerols obtained by enzymatic glycerolysis of ratfish liver oil. Differential scanning calorimetry revealed that crystallization and melting points decreased, while powder X-ray diffraction suggested changes in the crystal structure of the product when heated to 50 °C and held for longer than 180 min. Samples heated for a short time, rapidly underwent a polymorphic transition from the α to the ß polymorphic phase, whereas samples heated for long times remained in the α phase for 3 days. Polarized light microscopy also showed changes in the microstructure of the material due to the thermal treatment. These results suggest that the thermal history of lipidic encapsulation materials, above their melting point, can affect eventual encapsulation efficiency and product performance.


Assuntos
Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos/instrumentação , Lipídeos/química , Preparações Farmacêuticas/química , Varredura Diferencial de Calorimetria , Cristalização , Diglicerídeos/química , Sistemas de Liberação de Medicamentos/métodos , Estabilidade de Medicamentos , Temperatura Alta
18.
Food Chem ; 229: 28-34, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28372175

RESUMO

The concentration of polyunsaturated fatty acids by formation of urea adducts from three different sources was studied to elucidate the formation of ethyl carbamates in the course of these procedures. Two different methodologies were performed: with ethanol at high temperature and with hexane/ethanol mixtures at room temperature. It was proved that the amount of urethanes generated at high temperature was higher than at room temperature. Besides, subsequent washing steps of the PUFA fraction with water were efficient to remove the urethanes from the final products. The methodology at room temperature with 0.4mL ethanol and 3g urea provided good relationship between concentration and yield of the main bioactive PUFA, with the lowest formation of ethyl carbamates in the process.


Assuntos
Ácidos Graxos Insaturados/química , Ureia/química , Uretana/química
19.
J Chromatogr A ; 1078(1-2): 28-34, 2005 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-16007978

RESUMO

An HPLC method with evaporative light scattering detection (ELSD) for the simultaneous analysis of various lipid classes, particularly alkoxyglycerols and acylglycerols with very similar structure and polarity, has been developed. These lipid classes are frequently found in numerous fats and oils such as shark liver oils and can serve as substrates for lipase-catalyzed reactions. This method utilizes a silica column and a gradient elution of isooctane, methyl tert-butyl ether and 2-propanol in different proportions. Separation between squalene, sterol esters, and fatty acid ethyl esters has been achieved in a time of analysis slightly higher than 8 min. In addition, a good resolution between 1,3-diacylglycerols and free sterols was also attained in the same run, with a broad range of concentrations. Excellent precision regarding the retention times was obtained. The limit of detection for the different lipid classes studied was below 1 microg. Intra-day and inter-day variation of retention times and areas was also evaluated. The relative standard deviation of intra-day variation for retention times and areas never exceeded of 0.1 and 10, respectively. The HPLC-ELSD method was also optimized to separate and quantify the hydrolysis products of alkoxyglycerols and acylglycerols (mono-esterified and non-esterified alkoxyglycerols and mono-esterified and di-esterified acylglycerols) at the same time, rendering a useful method for the study of lipase-catalyzed reactions and a wide variety of fats and oils. The present methodology not only separates 18 different lipid classes with a good reproducibility, but it is also able to estimate the relative proportion in which they are found in a broad range of concentrations.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Éteres de Glicerila/análise , Lipídeos/análise , Animais , Óleos de Peixe/química , Luz , Óleos de Plantas/química , Reprodutibilidade dos Testes , Espalhamento de Radiação , Tubarões , Óleo de Girassol , Triglicerídeos/análise
20.
Artigo em Inglês | MEDLINE | ID: mdl-26904538

RESUMO

Enzymatic glycerolysis of Echium oil (Echium plantagineum) has been carried out in the presence of four commercial lipases. Different pretreatments of the reaction mixture, such as high pressure homogenization and addition of food grade monoolein as an emulsifier, were evaluated to test their influence on the glycerolysis reaction. In addition, the impact of reducing temperature and the utilization of a solvent generally recognized as safe as a flavoring agent, such as limonene, were also investigated. Conversion of ca. 60-70% of triacylglycerols and production of ca. 25-30% of monoacylglycerols (MAGs) were attained. Finally, at the best reaction conditions, the glycerolysis reaction was scaled up at pilot plant and the product mixture obtained was fractionated via molecular distillation. From this stage, two products were attained: a distillate containing 80% of MAGs and a residue containing approximately 50% of diacylglycerols and 50% of triacylglycerols. All these mixtures can be utilized as self-emulsifying vehicles for the formulation of bioactive substances and also as precursors for the production of structured bioactive lipids.

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