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1.
Molecules ; 26(18)2021 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-34576926

RESUMEN

Novel UV-curable polyurethane acrylate (PUA) resins were developed from rubber seed oil (RSO). Firstly, hydroxylated rubber seed oil (HRSO) was prepared via an alcoholysis reaction of RSO with glycerol, and then HRSO was reacted with isophorone diisocyanate (IPDI) and hydroxyethyl acrylate (HEA) to produce the RSO-based PUA (RSO-PUA) oligomer. FT-IR and 1H NMR spectra collectively revealed that the obtained RSO-PUA was successfully synthesized, and the calculated C=C functionality of oligomer was 2.27 per fatty acid. Subsequently, a series of UV-curable resins were prepared and their ultimate properties, as well as UV-curing kinetics, were investigated. Notably, the UV-cured materials with 40% trimethylolpropane triacrylate (TMPTA) displayed a tensile strength of 11.7 MPa, an adhesion of 2 grade, a pencil hardness of 3H, a flexibility of 2 mm, and a glass transition temperature up to 109.4 °C. Finally, the optimal resin was used for digital light processing (DLP) 3D printing. The critical exposure energy of RSO-PUA (15.20 mJ/cm2) was lower than a commercial resin. In general, this work offered a simple method to prepare woody plant oil-based high-performance PUA resins that could be applied in the 3D printing industry.


Asunto(s)
Acrilatos/química , Grasas Insaturadas/química , Poliuretanos/química , Impresión Tridimensional , Geles/química , Dureza , Hidroxilación , Espectroscopía de Resonancia Magnética , Resinas Sintéticas/química , Espectroscopía Infrarroja por Transformada de Fourier , Resistencia a la Tracción , Termogravimetría , Rayos Ultravioleta
2.
Food Chem ; 321: 126603, 2020 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-32244142

RESUMEN

The formation of 4-hydroxy-2-hexenal (HHE) and 4-hydroxy-2-nonenal (HNE) in vegetable oils and model oil systems were quantitatively assessed by RP-HPLC. Regardless of heating temperature, HHE was only detected in rapeseed and linseed oil, while HNE was detected in all tested oils. Intrinsic tocopherols suppressed HHE/HNE formation, but with similar inhibition rates (10.49-16.04%). Linear correlations were observed between HHE/HNE contents and corresponding n-3/6 fatty acid content in oils (R2 = 0.989/0.971). Model oil system revealed that HHE/HNE formation was closely related to methyl linolenate (MLN) and methyl linoleate (ML) contents. Low levels of ML (<0.5%) and MLN (<1.0%) did not lead to HHE/HNE formation. Therefore, HHE/HNE was classified as the characteristic aldehydes of n-3 and n-6 type oils, respectively. Heat map evaluation and regression analysis indicated HHE could predict the n-3 type oils oxidation, while HNE was a good indicator to estimate the oxidative deterioration of n-6 and n-9 type oils.


Asunto(s)
Aldehídos/química , Grasas Insaturadas/química , Aceites de Plantas/química , Cromatografía Líquida de Alta Presión , Ácidos Grasos/química , Calor , Oxidación-Reducción , Tocoferoles/química
3.
J Oleo Sci ; 69(3): 199-206, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32115546

RESUMEN

The wasted raw fat of chicken was extracted and recrystallized with slowly stir at various cooling temperature to get a clear out-looking and liquid chicken oil. The recovery percentage of liquid chicken oil is about 100, 87, 78, 49 and 0% at 25, 21, 17, 13 and 9°C. The chicken liquid oil has a new composition of fatty acids than the original oil (p < 0.05) and has a safety range in acid value and peroxide value. The fatty acid ratio of the liquid chicken oil obtained at 13°C to be 1:1.6:0.9 (SFA: MUFA: PUFA) is believed to be good dietary oil. The concept of ideal fatty acid ratio comes from Hayes' report (1:1.5:1, SFA: MUFA: PUFA) which is also found to mimic to human lipid fatty acid ratio. Statistically evaluation on Hayes' basis, it showed that the liquid chicken oil scored even better than the extra virgin olive oil. In conclusion, this study not only first open a new gate for the recycle of global raw chicken fat to a dietary oil but also give an evidence that the chicken oil seems more compatible to human lipid on the hypothetic basis of biocompatibility.


Asunto(s)
Grasas Insaturadas en la Dieta/aislamiento & purificación , Grasas/química , Animales , Pollos , Grasas Insaturadas/química , Ácidos Grasos/análisis , Temperatura
4.
Food Res Int ; 128: 108737, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31955784

RESUMEN

The aim of the study was to evaluate the degradation kinetics of carotenoids (CTs) in vacuum-fried papaya (Carica papaya L.) chips (PCs) during storage at four temperatures (15, 25, 35 and 45 °C) for 52 and 94 days for the two highest and lowest temperatures, respectively. Three treatments were applied to obtain the chips: chips with soy oil (24% lipids) and chips with palm oil (24% and 29% lipids). All the chips were packaged under air or nitrogen conditions. The CTs analyzed by HPLC-DAD were per order of content all-E-lycopene (LYC), Z-lycopene (Z-LYC), all-E-ß-carotene (BC), all-E-ß-cryptoxanthin (BCX) and Z-ß-carotene (Z-BC). The all-E-forms represented 80% of carotenoids in PCs. No significant carotenoid degradation was observed in the PCs packaged under nitrogen conditions during storage. For chips stored under air conditions, a second-order kinetic model best fitted the experimental data. Rate constants for LYC degradation were the lowest, while BCX and BC presented similar rate constants 4-23-fold higher depending on lipid composition. All Z-isomers degraded faster than all-E-forms, but Z-BC degraded only 2-4-fold faster than Z-LYC. All CTs followed Arrhenius temperature-dependency pattern and LYC showed the lowest activation energies (5-21 kJ/mol). A higher lipid content in the chips with palm oil enhanced the carotenoid retention in PCs. Moreover, a greater retention (p < 0.05) of CTs was observed in PCs with soy oil. The use of soy oil instead of palm oil increased the theoretical half-life (at 25 °C) by 2.2, 1.3 and 5.9-fold for BCX, BC and LYC, respectively. Packaging under nitrogen conditions and lipid composition may be considered to optimize the shelf life and carotenoid retention in PCs during storage.


Asunto(s)
Carica/química , Carotenoides/química , Culinaria , Grasas Insaturadas/química , Ácidos Grasos/química , Almacenamiento de Alimentos , Aceites de Plantas , Factores de Tiempo
5.
J Nutr ; 150(4): 818-825, 2020 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-31909809

RESUMEN

BACKGROUND: Walnuts have established lipid-/lipoprotein-lowering properties; however, their effect on lipoprotein subclasses has not been investigated. Furthermore, the mechanisms by which walnuts improve lipid/lipoprotein concentrations are incompletely understood. OBJECTIVES: We aimed to examine, as exploratory outcomes of this trial, the effect of replacing SFAs with unsaturated fats from walnuts or vegetable oils on lipoprotein subclasses, cholesterol efflux, and proprotein convertase subtilisin/kexin type 9 (PCSK9). METHODS: A randomized, crossover, controlled-feeding study was conducted in individuals at risk of cardiovascular disease (CVD) (n = 34; 62% men; mean ± SD age 44 ± 10 y; BMI: 30.1 ± 4.9 kg/m2). After a 2-wk run-in diet (12% SFAs, 7% PUFAs, 12% MUFAs), subjects consumed the following diets, in randomized order, for 6 wk: 1) walnut diet (WD) [57-99 g/d walnuts, 7% SFAs, 16% PUFAs [2.7% α-linolenic acid (ALA)], 9% MUFAs]; 2) walnut fatty acid-matched diet [7% SFAs, 16% PUFAs (2.6% ALA), 9% MUFAs]; and 3) oleic acid replaces ALA diet (ORAD) [7% SFAs, 14% PUFAs (0.4% ALA); 12% MUFAs] (all percentages listed are of total kilocalories ). Serum collected after the run-in (baseline) and each diet period was analyzed for lipoprotein classes and subclasses (vertical auto profile), cholesterol efflux, and PCSK9. Linear mixed models were used for data analysis. RESULTS: Compared with the ORAD, total cholesterol (mean ± SEM -8.9± 2.3 mg/dL; -5.1%; P < 0.001), non-HDL cholesterol (-7.4 ± 2.0 mg/dL; -5.4%; P = 0.001), and LDL cholesterol (-6.9 ± 1.9 mg/dL; -6.5%; P = 0.001) were lower after the WD; no other pairwise differences existed. There were no between-diet differences for HDL-cholesterol or LDL-cholesterol subclasses. Lipoprotein(a) [Lp(a)], cholesterol efflux, and PCSK9 were unchanged after the diets. CONCLUSIONS: In individuals at risk of CVD, replacement of SFAs with unsaturated fats from walnuts or vegetable oils improved lipid/lipoprotein classes, including LDL-cholesterol, non-HDL cholesterol, and total cholesterol, without an increase in Lp(a). These improvements were not explained by changes in cholesterol efflux capacity or PCSK9. This trial was registered at clinicaltrials.gov as NCT01235832.


Asunto(s)
Grasas Insaturadas/farmacología , Ácidos Grasos/administración & dosificación , Juglans/química , Lipoproteína(a)/sangre , Aceites de Plantas/química , Adulto , Anciano , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Estudios Cruzados , Dieta , Grasas Insaturadas/administración & dosificación , Grasas Insaturadas/química , Ácidos Grasos/química , Femenino , Análisis de los Alimentos , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Sobrepeso , Proproteína Convertasa 9/genética , Proproteína Convertasa 9/metabolismo
6.
Pak J Biol Sci ; 22(11): 537-544, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31930832

RESUMEN

BACKGROUND AND OBJECTIVE: Hyperlipidemia (HLP) is a leading cause for cardiovascular disease and atherosclerosis. Insufficient physical activity and unhealthy diet plays an important role in the progression of HLP. The present study was conducted to investigate the protective effect of 2 unconventional edible oils (purslane and garden cress) on hyperlipidemia. MATERIALS AND METHODS: Diet high in fat and cholesterol was used as inducer of hyperlipidemia in rats for 5 weeks. Plasma and hepatic lipid profile were assessed. Plasma levels of malondialdehyde (MDA) as lipid peroxidation indicator was determined. Liver transaminases (AST and ALT) as liver function indicator and kidney function (creatinine and urea) were evaluated. RESULTS: Results clarified significant elevation in plasma and liver lipid profiles, MDA, liver enzymes (AST and ALT) and kidney function (creatinine and urea) in hyperlipidemic control compared to normal control. Supplementation with purslane and garden cress seeds oils either in diet or oral showed significant improvement in all the studied parameters. CONCLUSION: Purslane and garden cress oils investigated in the current study produced significant reduction and elevation in bad and good cholesterol, respectively in plasma. Also both oils reduced hepatic lipid accumulation effectively in hyperlipidemia model in rats. Oils administration reduced plasma malondialdehyde and improves liver and kidney functions.


Asunto(s)
Grasas Insaturadas en la Dieta/aislamiento & purificación , Hiperlipidemias/prevención & control , Aceites de Plantas/aislamiento & purificación , Animales , Dieta Alta en Grasa , Grasas Insaturadas en la Dieta/administración & dosificación , Suplementos Dietéticos , Modelos Animales de Enfermedad , Grasas Insaturadas/química , Hiperlipidemias/sangre , Hiperlipidemias/dietoterapia , Hipolipemiantes/administración & dosificación , Hipolipemiantes/química , Hipolipemiantes/aislamiento & purificación , Lepidium sativum/química , Lípidos/sangre , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Aceites de Plantas/administración & dosificación , Aceites de Plantas/química , Portulaca/química , Ratas , Ratas Sprague-Dawley , Semillas/química
7.
Sci Rep ; 8(1): 18025, 2018 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-30575766

RESUMEN

Quality control and non-destructive monitoring are of notable interest of food and pharmaceutical industries. It relies on the ability of non-invasive inspection which can be employed for manufacturing process control. We hereby apply terahertz (THz) time-domain spectroscopy as non-destructive technique to monitor pure and degraded oils as well as hydrocarbon chemicals. Significant differences in the spectra of refractive index (RI) and absorption coefficient arising from the presence of ester linkages in the edible and technical oils were obtained. Explicit increase from 1.38 to 1.5 of the RI in all THz spectrum range was observed in hydrocarbons and mono-functional esters with the increase of molar mass. This fact is in contrast of RI dependence on molar mass in multi-functional esters, such as Adipate or vegetable oils, where it is around 1.54. Degradation products, Oleic Acid (OA) and water in particular, lead only to some changes in absorption coefficient and RI spectra of vegetable oils. We demonstrate that complex colloidal and supramolecular processes, such as dynamics of inverse micelles and oil hydrolysis, take part during oil degradation and are responsible for non-uniform dependence of optical properties on extent of degradation.


Asunto(s)
Grasas Insaturadas en la Dieta/análisis , Aceites/análisis , Preparaciones Farmacéuticas/análisis , Espectroscopía de Terahertz/métodos , Industria Farmacéutica/métodos , Industria Farmacéutica/normas , Estabilidad de Medicamentos , Grasas Insaturadas/química , Análisis de los Alimentos/métodos , Análisis de los Alimentos/normas , Aceites/química , Fenómenos Ópticos , Control de Calidad , Refractometría
8.
Appl Spectrosc ; 72(7): 1001-1013, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29718680

RESUMEN

This study assesses the capacity of a Fourier transform near-infrared (FT-NIR) spectrometer operating in the range 4500-12 000 cm-1 (833.33-2222.22 nm) to provide quantitative predictions for the parameters of acidity (AV), p-anisidine (pAV), total polar materials (TPM), peroxide value (PV), and oxidative stability index (OSI). 562 samples of frying oil were analyzed from 14 distinct types of oil. The calibrations obtained accounted for 96%, 95%, 99%, 92%, and 91% of the AV, pAV, TPM, PV, and OSI variations in the study set and the similarity between the standard error of laboratory (RMSEP) values and the reference method errors (RMSEL), enabling the authors to conclude that NIR technology has the capacity to replace traditional methods in thermo-oxidative degradation studies in frying oils.


Asunto(s)
Culinaria , Grasas Insaturadas en la Dieta/análisis , Grasas Insaturadas/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Espectroscopía Infrarroja Corta/métodos , Compuestos de Anilina/química , Concentración de Iones de Hidrógeno , Oxidación-Reducción , Reproducibilidad de los Resultados
9.
J Pak Med Assoc ; 67(6): 957-958, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28585605

RESUMEN

Fats and oils are one of the very important components of diet. However excess of either overall fat or certain kind of fats in the diet may result in negative health impacts including risk of obesity, dyslipidaemia, cardiovascular diseases and certain malignancies. It is thus important to have an optimum amount of fat in the diet, and also important to choose appropriate sources of fat in the diet. In this mini review we suggest pragmatic selection of cooking oils for optimum health benefits.


Asunto(s)
Culinaria , Grasas Insaturadas/química , Ghee , Aceites de Plantas/química , Dieta Saludable , Grasas de la Dieta , Grasas/química , Ácidos Grasos/química , Humanos
10.
J Environ Manage ; 203(Pt 3): 950-961, 2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-28554482

RESUMEN

This work describes the economic feasibility of hydroprocessed diesel fuel production via catalytic decarboxylation of rubber seed oil in Malaysia. A comprehensive techno-economic assessment is developed using Aspen HYSYS V8.0 software for process modelling and economic cost estimates. The profitability profile and minimum fuels selling price of this synthetic fuels production using rubber seed oil as biomass feedstock are assessed under a set of assumptions for what can be plausibly be achieved in 10-years framework. In this study, renewable diesel processing facility is modelled to be capable of processing 65,000 L of inedible oil per day and producing a total of 20 million litre of renewable diesel product per annual with assumed annual operational days of 347. With the forecasted renewable diesel retail price of 3.64 RM per kg, the pioneering renewable diesel project investment offers an assuring return of investment of 12.1% and net return as high as 1.35 million RM. Sensitivity analysis conducted showed that renewable diesel production cost is most sensitive to rubber seed oil price and hydrogen gas price, reflecting on the relative importance of feedstock prices in the overall profitability profile.


Asunto(s)
Grasas Insaturadas/análisis , Gasolina , Biomasa , Catálisis , Análisis Costo-Beneficio , Descarboxilación , Grasas Insaturadas/química , Gasolina/análisis , Hidrógeno , Inversiones en Salud , Malasia
11.
J Nutr ; 147(7): 1267-1274, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28515160

RESUMEN

Background: Hypertriglyceridemia is a common condition in the United States and is often associated with other metabolic disturbances, including insulin resistance, metabolic syndrome, and a predominance of small dense LDL particles.Objective: The objective of this trial was to evaluate the effects of a combination of egg protein (Epro) and unsaturated fatty acids (UFAs) substituted for refined starches and added sugars on insulin sensitivity (primary outcome) and other cardiometabolic health markers in overweight or obese adults with elevated triglyceride (TG) concentrations.Methods: Subjects with elevated TG concentrations were given test foods prepared by using Epro powder (∼8% of energy) and vegetable oil (∼8% of energy; Epro and UFA condition) or test foods prepared by using refined starch and sugar (∼16% of energy; carbohydrate condition) in a randomized, double-blind, controlled-feeding, crossover trial (3 wk/condition, 2-wk washout). The Matsuda insulin sensitivity index (MISI), fasting lipids, and other cardiometabolic health markers were assessed at baseline and the end of each diet condition. Responses were compared by using repeated-measures ANCOVA.Results: Twenty-five participants [11 men, 14 women; mean ± SEM: age, 46.3 ± 2.4 y; body mass index (in kg/m2), 31.8 ± 1.0] with a median (interquartile range limits) fasting serum TG concentration of 173 mg/dL (159, 228 mg/dL) completed the trial. The MISI value increased 18.1% ± 8.7% from baseline during the Epro and UFA condition and decreased 5.7% ± 6.2% from baseline during the carbohydrate condition (P < 0.001). The disposition index increased 23.8% ± 20.8% during the Epro and UFA condition compared with a decrease of 16.3% ± 18.8% during carbohydrate (P = 0.042) and LDL peak particle size increased 0.12 nm (-0.12, 0.28 nm) with Epro and UFA compared with a decrease of 0.15 nm (-0.33, 0.12 nm) with carbohydrate (P = 0.019). TG and VLDL cholesterol concentrations were lowered by 18.5% (-35.7%, -6.9%) and 18.6% (-34.8%, -7.4%), respectively, after the Epro and UFA condition and by 2.5% (-13.4%, 17.0%) and 3.6% (-12.5%, 16.2%), respectively, after the carbohydrate diet condition (P < 0.002).Conclusions: The replacement of refined carbohydrates with a combination of Epro and UFA increased the MISI value and altered several markers of cardiometabolic health in overweight or obese adults with elevated TG concentrations. This trial was registered at clinicaltrials.gov as NCT02924558.


Asunto(s)
Carbohidratos/química , Proteínas del Huevo/farmacología , Grasas Insaturadas/farmacología , Resistencia a la Insulina/fisiología , Sobrepeso/sangre , Triglicéridos/sangre , Adulto , Anciano , Dieta , Carbohidratos de la Dieta/administración & dosificación , Grasas de la Dieta/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Método Doble Ciego , Proteínas del Huevo/química , Grasas Insaturadas/química , Femenino , Análisis de los Alimentos , Humanos , Hipertrigliceridemia/sangre , Hipertrigliceridemia/dietoterapia , Masculino , Persona de Mediana Edad , Adulto Joven
12.
Biomed Res Int ; 2016: 1679734, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27419127

RESUMEN

Torrefaction process of biomass material is essential in converting them into biofuel with improved calorific value and physical strength. However, the production of torrefied biomass is loose, powdery, and nonuniform. One method of upgrading this material to improve their handling and combustion properties is by densification into briquettes of higher density than the original bulk density of the material. The effects of critical parameters of briquetting process that includes the type of biomass material used for torrefaction and briquetting, densification temperature, and composition of binder for torrefied biomass are studied and characterized. Starch is used as a binder in the study. The results showed that the briquette of torrefied rubber seed kernel (RSK) is better than torrefied palm oil shell (POS) in both calorific value and compressive strength. The best quality of briquettes is yielded from torrefied RSK at the ambient temperature of briquetting process with the composition of 60% water and 5% binder. The maximum compressive load for the briquettes of torrefied RSK is 141 N and the calorific value is 16 MJ/kg. Based on the economic evaluation analysis, the return of investment (ROI) for the mass production of both RSK and POS briquettes is estimated in 2-year period and the annual profit after payback was approximately 107,428.6 USD.


Asunto(s)
Grasas Insaturadas/química , Aceites de Plantas/química , Biocombustibles , Biomasa , Fuerza Compresiva , Aceite de Palma , Temperatura , Agua/química
13.
J Biotechnol ; 220: 92-9, 2016 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-26795690

RESUMEN

In this work, the ethanolysis of triglycerides catalyzed by immobilized lipase was studied, focusing on the secondary reaction of acyl migration. The catalytic tests were performed in a solvent-free reaction medium using Novozym 435 as biocatalyst. The selected experimental variables were biocatalyst loading (5-20mg), reaction time (30-90min), and chain length of the fatty acids in triglycerides with and without unsaturation (short (triacetin), medium (tricaprylin) and long (tripalmitin/triolein)). The formation of 2-monoglyceride by ethanolysis of triglycerides was favored by long reaction times and large biocatalyst loading with saturated short- to medium-chain triglycerides. In the case of long-chain triglycerides, the formation of this monoglyceride was widely limited by acyl migration. In turn, acyl migration increased the yield of ethyl esters and minimized the content of monoglycerides and diglycerides. Thus, the enzymatic synthesis of biodiesel was favored by long-chain triglycerides (which favor the acyl migration), long reaction times and large biocatalyst loading. The conversion of acylglycerides made from long-chain fatty acids with unsaturation was relatively low due to limitations in their access to the active site of the lipase.


Asunto(s)
Lipasa/química , Lipasa/metabolismo , Modelos Químicos , Triglicéridos/síntesis química , Biocombustibles , Cromatografía de Gases/métodos , Diglicéridos/síntesis química , Diglicéridos/química , Enzimas/química , Enzimas Inmovilizadas/química , Ésteres/síntesis química , Éteres de Etila/síntesis química , Éteres de Etila/química , Grasas Insaturadas/síntesis química , Grasas Insaturadas/química , Ácidos Grasos/química , Ácidos Grasos/metabolismo , Proteínas Fúngicas , Glicerol/síntesis química , Glicerol/química , Cinética , Monoglicéridos/síntesis química , Monoglicéridos/química , Solventes/química , Triglicéridos/química
14.
Food Funct ; 6(6): 1999-2007, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26018773

RESUMEN

The antioxidant activity of ethyl and octyl hydroxytyrosyl ethers toward lipids was determined using the Rancimat and open cup methods at high temperatures and 50 °C, respectively. The effect of the unsaturation of the matrix was evaluated using sunflower, soya, and fish refined oils. The antioxidant activities of alkyl hydroxytyrosyl ethers (HTy ethers), hydroxytyrosyl esters, and free hydroxytyrosol are similar, and are much higher than that of α-tocopherol at the same millimolar concentration. The relationship between the induction period and the concentration of the HTy ethers is a sigmoidal curve; an accurate concentration of HTy ethers is necessary to achieve maximum activity, as it increases with the level of matrix unsaturation. The presence of tocopherols in commercial oils affects the antioxidant effect of HTy ethers. Thus, the addition of a low concentration of HTy ethers results in a positive effect, whereas the effect of the addition of high amounts of ethers is slightly less than that of the phenol alone. The addition of HTy ethers to commercial refined oils increases the stability of the oils and preserves tocopherols and polyunsaturated fatty acids from oxidation, enabling the oils to maintain their nutritional properties for longer periods of time.


Asunto(s)
Antioxidantes/química , Grasas Insaturadas en la Dieta/análisis , Grasas Insaturadas/química , Conservantes de Alimentos/química , Alcohol Feniletílico/análogos & derivados , Alquilación , Éteres/química , Grasas Insaturadas/análisis , Aceites de Pescado/química , Calidad de los Alimentos , Almacenamiento de Alimentos , Calor/efectos adversos , Cinética , Peróxidos Lipídicos/análisis , Oxidación-Reducción , Alcohol Feniletílico/química , Aceites de Plantas/química , Aceite de Soja/química , Aceite de Girasol , Tocoferoles/análisis , Tocoferoles/química
15.
Rapid Commun Mass Spectrom ; 28(22): 2461-70, 2014 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-25303475

RESUMEN

RATIONALE: Unsaturated lipids play a crucial role in cellular processes as signaling factors, membrane building blocks or energy storage molecules. However, adequate mass spectrometry imaging of this diverse group of molecules remains challenging. In this study we implemented silver cationization for direct analysis by infrared matrix-assisted laser desorption electrospray ionization (IR-MALDESI) to enhance the ion abundances for olefinic lipids and facilitate peak assignment. METHODS: Trace amounts of silver nitrate were doped into the electrospray solvent of an IR-MALDESI imaging source coupled to an Orbitrap mass analyzer. Calcifediol was examined as a model compound to demonstrate the effect of silver dopants on sensitivity and assay robustness. Dried human serum spots were subsequently analyzed to compare Ag-doped solvents with previously described solvent compositions. Mass differences as well as ion abundance ratio filters were employed to interpret results based on the characteristic isotopic pattern of silver. RESULTS: Olefinic lipids were readily observed as silver adducts in IR-MALDESI analyses. Silver cationization decreased the limit of detection for calcifediol by at least one order of magnitude and was not affected in complex biological matrices. The ion abundance ratio and mass difference of [M + (107) Ag(+)](+) and [M + (109) Ag(+)](+) were successfully applied to facilitate the spectral assignment of silver adducts. Overall, silver cationization increased the analyte coverage in human serum by 43% compared with a standard IR-MALDESI approach. CONCLUSIONS: Silver cationization has been shown to enhance IR-MALDESI sensitivity and selectivity for unsaturated lipids, even when applied to complex samples. Increased compound coverage, enhanced robustness as well as the developed tools for peak assignment and mapping of isotopic patterns will clearly benefit future mass spectrometry imaging studies.


Asunto(s)
Plata/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Alquenos/química , Pruebas con Sangre Seca , Grasas Insaturadas/análisis , Grasas Insaturadas/química , Humanos , Masculino , Espectrometría de Masa por Ionización de Electrospray/métodos
16.
J Oleo Sci ; 63(7): 709-16, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24976614

RESUMEN

Para rubber seed was macerated in petroleum ether and n-hexane, individually, for 30 min. The extraction was additionally performed by reflux and soxhlet for 6 h with the same solvent and proportion. Soxhlet extraction by petroleum ether afforded the greatest extractive yield (22.90 ± 0.92%). Although antioxidant activity by means of 1, 1-diphenyl-2-picrylhydrazyl (DPPH) assay was insignificantly differed in soxhleted (8.90 ± 1.15%) and refluxed (9.02 ± 0.71%) by n-hexane, soxhlet extraction by n-hexane was significantly (p < 0.05) potent scavenged 2,2'-azino-bis(3-ethylbenzothaiazoline)-6-sulfonic acid) or ABTS radical with trolox equivalent antioxidant capacity (TEAC) of 66.54 ± 6.88 mg/100 g oil. This extract was non cytotoxic towards normal human fibroblast cells. In addition, oleic acid and palmitic acid were determined at a greater content than in the seed of para rubber cultivated in Malaysia, although linoleic and stearic acid contents were not differed. This bright yellow extract was further evaluated on other physicochemical characters. The determined specific gravity, refractive index, iodine value, peroxide value and saponification value were in the range of commercialized vegetable oils used as cosmetic raw material. Therefore, Para rubber seed oil is highlighted as the promising ecological ingredient appraisal for cosmetics. Transforming of the seed that is by-product of the important industrial crop of Thailand into cosmetics is encouraged accordingly.


Asunto(s)
Cosméticos , Grasas Insaturadas , Células Cultivadas , Fenómenos Químicos , Grasas Insaturadas/química , Grasas Insaturadas/aislamiento & purificación , Grasas Insaturadas/farmacocinética , Fibroblastos/efectos de los fármacos , Depuradores de Radicales Libres , Humanos , Ácido Oléico/análisis , Ácido Palmítico/análisis , Piel/citología , Tailandia
17.
Rapid Commun Mass Spectrom ; 28(10): 1144-52, 2014 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-24711277

RESUMEN

RATIONALE: Studies of archaeal glycerol dibiphytanyl glycerol tetraethers (GDGTs) in the environment and cultures have exclusively focused on compounds with fully saturated alkyl moieties. Here we report a number of novel unsaturated GDGTs (uns-GDGTs) whose alkyl chains contain up to six double bonds and zero to two cyclopentyl moieties. METHODS: The identification of these lipids was achieved via comparison of lipid distribution before and after hydrogenation, characteristic retention time patterns, and diagnostic ions using liquid chromatography/tandem mass spectrometry (LC/MS/MS), and ether cleavage products using gas chromatography/mass spectrometry (GC/MS). Isomerism resulting from different unsaturation patterns in the alkyl moieties was observed and specific positions of double bonds in the biphytene and biphytadiene moieties were tentatively assigned. RESULTS: Uns-GDGTs were detected in sediment and microbial mat samples as both core lipids (CLs) and intact polar lipids (IPLs) associated with mono- or diglycosyl or phosphatidylglycerol headgroups. However, these lipids were overlooked in past investigations because conventional methods for archaeal lipid analysis are unsuitable for uns-GDGTs. Samples from distinct marine environments (Black Sea, Cariaco Basin, Discovery Basin, Eastern Mediterranean Sea, upwelling area off NW Africa, and seep sites off Crimea and Pakistan) were screened for uns-GDGTs using a new LC/MS protocol. The results show that uns-GDGTs contribute significantly to the archaeal lipid pool in anoxic methane-rich environments (Black Sea, Cariaco Basin, and both seep sites) but they were barely detected in the oxic or hypersaline settings. CONCLUSIONS: The characteristic distribution of uns-GDGTs implies that they are attractive targets for future studies aiming at the chemotaxonomy of uncultivated archaea and regulation of uns-GDGT biosynthesis.


Asunto(s)
Archaea/química , Éteres de Glicerilo/química , Lípidos/química , Mar Negro , Grasas Insaturadas/química , Cromatografía de Gases y Espectrometría de Masas , Sedimentos Geológicos/química
18.
J Chromatogr A ; 1240: 45-51, 2012 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-22520640

RESUMEN

In the present work, we developed a novel dispersive microextraction technique by combining the advantages of liquid-phase microextraction (LPME) and magnetic solid-phase extraction (MSPE). In this method, trace amount of water directly absorbed on bare Fe3O4 to form water-coated Fe3O4 (W-Fe3O4) and rapid extraction can be achieved while W-Fe3O4 dispersed in the sample solution. The analyte adsorbed W-Fe3O4 can be easily collected and isolated from sample solution by application of a magnet. It was worth noting that in the proposed method water was used as extractant and Fe3O4 served as the supporter and retriever of water. The performance of the method was evaluated by extraction of 3-monochloropropane-1,2-diol (3-MCPD) from edible oils. The extracted 3-MCPD was then derived by a silylanization reagent (1-trimethylsilylimidazole) before gas chromatography-mass spectrometry (GC-MS) analysis. Several parameters that affected the extraction and derivatization efficiency were investigated. Our results showed that the limit of detection for 3-MCPD was 1.1 ng/g. The recoveries in spiked oil samples were in the range of 70.0-104.9% with the RSDs less than 5.6% (intra-day) and 6.4% (inter-day). Taken together, the simple, rapid and cost-effective method developed in current study, offers a potential application for the extraction and preconcentration of hydrophilic analytes from complex fatty samples.


Asunto(s)
Grasas Insaturadas en la Dieta/análisis , Grasas Insaturadas/química , Óxido Ferrosoférrico/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Glicerol/análogos & derivados , Microextracción en Fase Sólida/métodos , Glicerol/análisis , Interacciones Hidrofóbicas e Hidrofílicas , Imidazoles/química , Límite de Detección , Modelos Lineales , Microextracción en Fase Líquida/métodos , Reproducibilidad de los Resultados , Compuestos de Trimetilsililo/química , Agua/química , alfa-Clorhidrina
19.
J Oleo Sci ; 61(2): 81-8, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22277892

RESUMEN

This study aims to examine methods and the most suitable conditions for producing methyl ester from crude rubber seed oil. An acid esterification-alkaline transesterification process is proposed. In the experiment, the 20% FFA of crude rubber seed oil could be reduced to 3% FFA by acid esterification. The product after esterified was then tranesterified by alkaline transesterification process. By this method, the maximum yield of methyl ester was 90% by mass. The overall consumption of methanol was 10.5:1 by molar ratio. The yielded methyl ester was tested for its fuel properties and met required standards. The major fatty acid methyl ester compositions were analyzed and constituted of methyl linoleate 41.57%, methyl oleate 24.87%, and methyl lonolenate 15.16%. Therefore, the cetane number of methyl ester could be estimated as 47.85, while the tested result of motor cetane number was 51.20.


Asunto(s)
Álcalis/química , Ésteres/síntesis química , Grasas Insaturadas/química , Ácidos Grasos no Esterificados/química , Catálisis , Ésteres/química
20.
Neth J Med ; 69(9): 372-8, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21978979

RESUMEN

The dietary intake of saturated fatty acids (SAFA) is associated with a modest increase in serum total cholesterol, but not with cardiovascular disease (CVD). Replacing dietary SAFA with carbohydrates (CHO), notably those with a high glycaemic index, is associated with an increase in CVD risk in observational cohorts, while replacing SAFA with polyunsaturated fatty acids (PUFA) is associated with reduced CVD risk. However, replacing a combination of SAFA and trans-fatty acids with n-6 PUFA (notably linoleic acid) in controlled trials showed no indication of benefit and a signal toward increased coronary heart disease risk, suggesting that n-3 PUFA may be responsible for the protective association between total PUFA and CVD. High CHO intakes stimulate hepatic SAFA synthesis and conservation of dietary SAFA . Hepatic de novo lipogenesis from CHO is also stimulated during eucaloric dietary substitution of SAFA by CHO with high glycaemic index in normo-insulinaemic subjects and during hypocaloric high-CHO/low-fat diets in subjects with the metabolic syndrome. The accumulation of SAFA stimulates chronic systemic low-grade inflammation through its mimicking of bacterial lipopolysaccharides and÷or the induction of other pro-inflammatory stimuli. The resulting systemic low-grade inflammation promotes insulin resistance, reallocation of energy-rich substrates and atherogenic dyslipidaemia that concertedly give rise to increased CVD risk. We conclude that avoidance of SAFA accumulation by reducing the intake of CHO with high glycaemic index is more effective in the prevention of CVD than reducing SAFA intake per se.


Asunto(s)
Enfermedades Cardiovasculares/etiología , Carbohidratos de la Dieta/administración & dosificación , Grasas de la Dieta/administración & dosificación , Ácidos Grasos/administración & dosificación , Aterosclerosis/prevención & control , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/prevención & control , Colesterol/sangre , Carbohidratos de la Dieta/efectos adversos , Grasas de la Dieta/efectos adversos , Grasas Insaturadas en la Dieta/administración & dosificación , Grasas Insaturadas en la Dieta/efectos adversos , Grasas Insaturadas/administración & dosificación , Grasas Insaturadas/efectos adversos , Grasas Insaturadas/química , Humanos , Inflamación/etiología , Inflamación/prevención & control , Lipoproteínas LDL/sangre
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