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1.
J Chem Ecol ; 47(7): 664-679, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34196857

RESUMO

Larval Diaphania indica (Saunders) (Lepidoptera: Crambidae) cause complete defoliation of Trichosanthes anguina L. and reduce crop yield in India. Females lay eggs on the leaf surface, and therefore leaf surface waxes are potentially involved in host selection. Alkanes and free fatty acids are the major constituents of leaf surface waxes, so a study was conducted to determine whether these wax constituents from three T. anguina cultivars (MNSR-1, Baruipur Long, and Polo No.1) could act as short-range attractants and oviposition stimulants in D. indica females. Twenty n-alkanes from n-C14 to n-C36 and 13 free fatty acids from C12:0 to C21:0 were detected in the leaf surface waxes of these cultivars. Heptadecane and stearic acid were predominant among n-alkanes and free fatty acids, respectively, in these cultivars. Females showed attraction towards one leaf equivalent surface wax of each of these cultivars against solvent controls (petroleum ether) in Y-tube olfactometer bioassays. A synthetic blend of heptadecane, eicosane, hexacosane, and stearic acid, a synthetic blend of hexacosane and stearic acid, and a synthetic blend of pentadecane and stearic acid comparable to amounts present in one leaf equivalent surface wax of MNSR-1, Baruipur Long, and Polo No.1, respectively, were short-range attractants and oviposition stimulants in D. indica. Female egg laying responses were similar to each of these blends, providing information that could be used to developing baited traps in integrated pest management (IPM) programs.


Assuntos
Cucurbitaceae/metabolismo , Mariposas/fisiologia , Oviposição/efeitos dos fármacos , Ceras/farmacologia , Alcanos/análise , Alcanos/isolamento & purificação , Alcanos/farmacologia , Animais , Análise Discriminante , Ácidos Graxos não Esterificados/análise , Ácidos Graxos não Esterificados/isolamento & purificação , Ácidos Graxos não Esterificados/farmacologia , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Larva/efeitos dos fármacos , Larva/fisiologia , Mariposas/crescimento & desenvolvimento , Olfatometria , Folhas de Planta/metabolismo , Ceras/química , Ceras/isolamento & purificação
2.
Molecules ; 25(10)2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32423117

RESUMO

The aim of this study was to evaluate the development of volatile compounds in yogurt samples obtained from goats fed a dietary supplementation with olive leaves (OL). For this purpose, thirty Saanen goats were divided into two homogeneous groups of 15 goats each: a control group that received a standard diet (CG) and an experimental group whose diet was supplemented with olive leaves (OLG). The trial lasted 28 days, at the end of which the milk of each group was collected and used for yogurt production. Immediately after production, and after 7 days of storage at 4 °C in the absence of light, the yogurt samples were characterized in terms of fatty acid profile, oxidative stability and volatile compounds by the solid-phase microextraction (SPME)-GC/MS technique. Dietary OL supplementation positively affected the fatty acid composition, inducing a significant increase in the relative proportion of unsaturated fatty acids, mainly oleic acid (C18:1 cis9) and linolenic acid (C18:3). With regard to the volatile profile, both in fresh and yogurt samples stored for 7 days, the OL supplementation induced an increase in free fatty acids, probably due to an increase in lipolysis carried out by microbial and endogenous milk enzymes. Specifically, the largest variations were found for C6, C7, C8 and C10 free fatty acids. In the same samples, a significant decrease in aldehydes, mainly heptanal and nonanal, was also detected, supporting-at least in part-an improvement in the oxidative stability. Moreover, alcohols, esters and ketones appeared lower in OLG samples, while no significant variations were observed for lactones. These findings suggest the positive role of dietary OL supplementation in the production of goats' milk yogurt, with characteristics potentially indicative of an improvement in nutritional properties and flavor.


Assuntos
Ração Animal , Ácidos Graxos não Esterificados/isolamento & purificação , Ácidos Graxos Insaturados/isolamento & purificação , Olea/química , Compostos Orgânicos Voláteis/isolamento & purificação , Iogurte/análise , Álcoois/classificação , Álcoois/isolamento & purificação , Aldeídos/isolamento & purificação , Animais , Ésteres/classificação , Ésteres/isolamento & purificação , Ácidos Graxos não Esterificados/classificação , Ácidos Graxos Insaturados/classificação , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Cabras , Cetonas/classificação , Cetonas/isolamento & purificação , Lactonas/classificação , Lactonas/isolamento & purificação , Leite/química , Folhas de Planta/química , Microextração em Fase Sólida/métodos , Compostos Orgânicos Voláteis/classificação
3.
Eur J Immunol ; 43(6): 1578-87, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23504601

RESUMO

Adipose tissue contains several immune cells whose number and phenotype vary depending on the adiposity. In the present study, we show that IFN-γ(+) CD4(+) T cells are enriched in human adipose tissue compared with in blood. To gain insight into the underlying mechanisms, we investigated the possibility that human adipocytes modulate CD4(+) T-cell cytokine production and proliferation and show that CD4(+) T cells produced increased levels of IFN-γ when activated in the presence of adipocytes. This effect was mediated by soluble mediators, as shown in transwell and adipocyte-conditioned medium (ACM) transfer experiments. Additionally, ACM induced increased proliferation of CD4(+) T cells upon activation. Intriguingly, the proliferation-enhancing effect resided mainly in the lipid fraction of ACM, as shown upon separation of the protein and lipid fraction. Further separation of these lipids based on polarity revealed that the modulatory effect is confined to fractions containing free fatty acids. All identified fatty acids were able to individually enhance T-cell proliferation. These data indicate that adipocytes can modulate CD4(+) T-cell function through the release of lipids. Remarkably, free fatty acids were the most prominent modulators of T-cell proliferation, possibly leading to an accumulation of these cells in adipose tissue.


Assuntos
Adipócitos/imunologia , Linfócitos T CD4-Positivos/imunologia , Ácidos Graxos não Esterificados/imunologia , Obesidade/imunologia , Adipócitos/patologia , Tecido Adiposo/patologia , Comunicação Celular , Proliferação de Células , Células Cultivadas , Técnicas de Cocultura , Meios de Cultivo Condicionados/química , Ácidos Graxos não Esterificados/isolamento & purificação , Humanos , Imunomodulação , Interferon gama/imunologia
4.
Phytochem Anal ; 25(3): 241-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24453169

RESUMO

INTRODUCTION: Olive oil is a very important product to human health since it inhibits formation of free radicals, tumour growth, lesions and inflammatory substances. High concentrations of free fatty acids in olive oils results in lipid deterioration due to oxidative or hydrolytic rancidity. OBJECTIVE: To optimise an alternative capillary zone electrophoresis methodology, under ultraviolet indirect detection and to determine free fatty acids in edible vegetable oils without derivatisation steps in sample preparation. METHODS: The condition used consisted of 15 mm NaH2 PO4 -Na2 HPO4 at pH ~6.86, 4.0 mm of sodium dodecybenzenesulphonate, 8.3 mm of Brij 35®, 45% v/v of acetonitrile and 2.1% of 1-octanol, injection at 12.0 mbar of pressure for 4 s, +19 kV of applied voltage and indirect detection at 224 nm, within an analysis time of 11 min. RESULTS: The capillary zone electrophoresis method was successfully applied to determination of free fatty acids in extra virgin olive oil, virgin olive oil and soybean oil samples. The comparison with the official volumetric titration method showed no significant difference within the 95% confidence interval. CONCLUSION: The main advantage to the proposed method is the possibility to observe the individual amount of the free fatty acids, which would be useful for researchers interested in studying the effect of the free fatty acids profile on oxidative process in food.


Assuntos
Eletroforese Capilar/métodos , Ácidos Graxos não Esterificados/isolamento & purificação , Óleos de Plantas/isolamento & purificação , Ácidos Graxos não Esterificados/análise , Limite de Detecção , Azeite de Oliva , Óleos de Plantas/química , Óleos de Plantas/classificação , Análise de Regressão , Fatores de Tempo
5.
J Infect Dis ; 208(12): 1943-52, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24068703

RESUMO

BACKGROUND: Hepatitis C virus (HCV) is spread through direct contact with blood, although alternative routes of transmission may contribute to the global burden. Perinatal infection occurs in up to 5% of HCV-infected mothers, and presence of HCV RNA in breast milk has been reported. We investigated the influence of breast milk on HCV infectiousness. METHODS/RESULTS: Human breast milk reduced HCV infectivity in a dose-dependent manner. This effect was species-specific because milk from various animals did not inhibit HCV infection. Treatment of HCV with human breast milk did not compromise integrity of viral RNA or capsids but destroyed the lipid envelope. Fractionation of breast milk revealed that the antiviral activity is present in the cream fraction containing the fat. Proteolytic digestion of milk proteins had no influence on its antiviral activity, whereas prolonged storage at 4°C increased antiviral activity. Notably, pretreatment with a lipase inhibitor ablated the antiviral activity and specific free fatty acids of breast milk were antiviral. CONCLUSIONS: The antiviral activity of breast milk is linked to endogenous lipase-dependent generation of free fatty acids, which destroy the viral lipid envelope. Therefore, nursing by HCV-positive mothers is unlikely to play a major role in vertical transmission.


Assuntos
Hepacivirus/efeitos dos fármacos , Leite Humano/fisiologia , Inativação de Vírus/efeitos dos fármacos , Linhagem Celular Tumoral , Estabilidade de Medicamentos , Endopeptidase K/farmacologia , Ácidos Graxos não Esterificados/química , Ácidos Graxos não Esterificados/isolamento & purificação , Ácidos Graxos não Esterificados/farmacologia , Armazenamento de Alimentos , Hepacivirus/patogenicidade , Hepatite C/transmissão , Hepatite C/virologia , Humanos , Transmissão Vertical de Doenças Infecciosas , Lipase/antagonistas & inibidores , Leite Humano/química , Leite Humano/enzimologia , Leite Humano/virologia , Modelos Biológicos , Carga Viral/efeitos dos fármacos , Vírion/efeitos dos fármacos
6.
Prikl Biokhim Mikrobiol ; 50(1): 85-94, 2014.
Artigo em Russo | MEDLINE | ID: mdl-25272757

RESUMO

The biological activity of lipids and photosynthetic pigments of the kelp Sargassum pallidum (Turner) C. Agardh has been studied. Free fatty acids and their esters demonstrated considerable antimicrobial activity against bacteria (Staphylococcus aureus[ital] and Escherichia coli), yeast-like fungi (Candida albicans), and opportunistic pathogenic (Aspergilius niger) and phytopathogenic (Fusarium oxysporum, and Septoria glycines) fungi. Glyceroglycolipids and neutral lipids demonstrated moderate activity. Fucoxanthin and chlorophylls weakly suppressed the growth of microorganisms. None of the studied substances demonstrated activity against Ehrlich's carcinoma. It was shown that the season of weed harvesting affected both antimicrobial and hemolytic activities of different lipids due to changes in their fatty acid composition.


Assuntos
Anti-Infecciosos/farmacologia , Ácidos Graxos não Esterificados/farmacologia , Ácidos Graxos/farmacologia , Pigmentos Biológicos/farmacologia , Sargassum/química , Animais , Anti-Infecciosos/isolamento & purificação , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Carcinoma de Ehrlich/patologia , Sobrevivência Celular/efeitos dos fármacos , Clorofila/isolamento & purificação , Clorofila/farmacologia , Eritrócitos/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Ácidos Graxos/isolamento & purificação , Ácidos Graxos não Esterificados/isolamento & purificação , Fusarium/efeitos dos fármacos , Fusarium/crescimento & desenvolvimento , Glicolipídeos/isolamento & purificação , Glicolipídeos/farmacologia , Camundongos , Fotossíntese/fisiologia , Pigmentos Biológicos/isolamento & purificação , Estações do Ano , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Células Tumorais Cultivadas , Xantofilas/isolamento & purificação , Xantofilas/farmacologia
7.
Clin Chem Lab Med ; 51(4): 799-810, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23006900

RESUMO

BACKGROUND: Knowledge of the fatty acid composition of lipid classes in human plasma is an important factor in the investigation of human metabolism. Therefore, a method for the analysis of neutral lipid (NL), phospholipid (PL) and free fatty acids (FFA) in human plasma has been developed and validated. METHODS: Separation of lipid classes was carried out by solid phase extraction of the lipid extract. The fractions were transesterified and the resulting fatty acid methyl esters were determined by GC/FID. For the method to be validated, precision, detection and quantification limits, as well as recovery, were determined for combined lipid extraction, solid phase extraction and GC analysis. RESULTS: The lipid extraction was miniaturized and simplified by application of an ultrasound 'Sonotrode'. The resolution of lipid classes was optimized with appropriate standards added to a representative plasma sample. In addition, a rapid derivatization procedure using trimethylsulfoniumhydroxide was established. Low determination limits (1.5, 0.2 and 1.3 µg/g plasma for NL, PL and FFA, respectively) indicate that the method's sensitivity is sufficient to quantify even minor components. Furthermore, recovery for NL and PL fatty acids was found to range from 80% to 110%. The results were similar for FFA apart from more polar free fatty acids due to their higher solubility in water. Repetitive measurements showed very good precision apart from the long chain PUFA for which the coefficients of variation were significantly higher. CONCLUSIONS: The present method is applicable to the quantitation of fatty acids in lipid classes of human plasma including several minor components.


Assuntos
Ácidos Graxos não Esterificados/sangue , Cromatografia Gasosa-Espectrometria de Massas , Fosfolipídeos/sangue , Ácidos Graxos não Esterificados/isolamento & purificação , Ácidos Graxos não Esterificados/normas , Ácidos Graxos Insaturados/sangue , Ácidos Graxos Insaturados/isolamento & purificação , Ácidos Graxos Insaturados/normas , Cromatografia Gasosa-Espectrometria de Massas/normas , Humanos , Hidróxidos/química , Fosfolipídeos/isolamento & purificação , Fosfolipídeos/normas , Compostos de Potássio/química , Padrões de Referência , Extração em Fase Sólida
8.
J Sep Sci ; 33(2): 143-54, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20041447

RESUMO

Free fatty acids were derivatized as amides (DFFA) by reaction with (R)-(+)-1-phenylethylamine, using a simple, fast and robust reaction scheme. A HPLC method with diode array and ESI MS detection was developed for the analysis of the derivatized substances. Six fatty acids were used in the method development: myristic, linoleic, palmitic, oleic, margaric and stearic acids. Under these conditions the elution of the DFFA are well resolved with retention times raging from 6.9 to 16.0 min. Fatty acids were extracted from cemetery soil and from adipocere formation experimental soils using a Soxhlet extraction, using as solvent ether/dichloromethane (1:1). Each DFFA is characterized by three m/z peaks: molecular weight of the substance; molecular weight of a dimer of the substance; the molecular weight of the dimer plus the atomic mass of sodium. The analysis of soil samples detected the six fatty acids used in the method developed plus palmitoleic and pentadecanoic. Beside this set of eight fatty acids other 13 fatty acids were detected in trace quantities or only in some soils and some were tentatively assigned as: 10-hydroxystearic, myristoleic, heptadecenoic and arachidic acids.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Ácidos Graxos não Esterificados/análise , Mudanças Depois da Morte , Solo/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Animais , Cemitérios , Ácidos Graxos/análise , Ácidos Graxos/química , Ácidos Graxos/isolamento & purificação , Ácidos Graxos não Esterificados/química , Ácidos Graxos não Esterificados/isolamento & purificação , Ácidos Graxos Insaturados/análise , Ácidos Graxos Insaturados/química , Ácidos Graxos Insaturados/isolamento & purificação , Medicina Legal/métodos , Humanos , Fenetilaminas/química , Espectrofotometria Ultravioleta , Sus scrofa
9.
J Oleo Sci ; 69(8): 859-864, 2020 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-32641607

RESUMO

Chicken skin -a poultry meat industries waste- has been used in this work as a source for the production of pure free fatty acids. Chicken skin fat was extracted using dry rendering method. Physical and chemical parameters of that fat were determined. Also, its fatty acids composition has been identified by GC-MS after its esterification as oleic, palmitic, linoleic, stearic, myristic, lauric, linolenic, behenic, arachidonic, arachidic, palmitoleic, and paullinic acids, and others as traces. The extracted fat was then hydrolyzed into mixture of free fatty acids and glycerol, the free fatty acid mixture was separated, then it was cooled in order to separate saturated and unsaturated fatty acids from each other. Oleic, Palmitic, Linoleic and Stearic Acids were extracted individually in pure form using supercritical CO2 extractor. Moreover, oleic, linoleic, palmitoleic, linolenic, and paullinic acids were extracted individually in pure form using cooling centrifuge sigma 3-18KS. All of the separated individual fatty acids were confirmed according to their melting point, GC-MS after esterification, elemental analysis and mass spectrometry (ms) of the corresponding methyl ester in order to detect the corresponding molecular ion peak. Therefore, these new two methods could afford the very expensive pure fatty acids with a low cast.


Assuntos
Centrifugação/métodos , Galinhas , Ácidos Graxos não Esterificados/isolamento & purificação , Produtos Avícolas , Pele/química , Extração em Fase Sólida/métodos , Animais , Temperatura Baixa , Esterificação , Gorduras Insaturadas/isolamento & purificação , Ácidos Graxos/isolamento & purificação , Ácidos Graxos não Esterificados/análise , Cromatografia Gasosa-Espectrometria de Massas , Extração em Fase Sólida/instrumentação , Temperatura de Transição
10.
Food Chem ; 297: 124998, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31253278

RESUMO

The analysis of free fatty acids (FFAs) in edible oils can provide important information for quality control and oil authentication. Herein, we report the comprehensive profiling of FFAs in edible oils via magnetic dispersive extraction combined with comprehensive two-dimensional gas chromatography-mass spectrometry (GC × GC-MS). A magnetic extractant was designed for dispersive extraction of FFAs. The extraction conditions were carefully optimized. To assess the extraction method, we first use the method for analysis of 7 targeted FFAs. The limits of detection range from 5.6 to 25.8 ng g-1, and the recoveries in oil samples are 81%-107%. We then performed comprehensive profiling of untargeted FFAs in oil by combining the extraction method with GC × GC-MS. A total of 64 FFAs were identified positively or putatively. The proposed method can provide FFA fingerprint data to guide the processing, storage and authentication of edible oils.


Assuntos
Ácidos Graxos não Esterificados/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Magnetismo , Óleos de Plantas/química , Amônia/química , Ácidos Graxos não Esterificados/isolamento & purificação , Óxido Ferroso-Férrico/química , Metanol/química , Dióxido de Silício/química
11.
Artigo em Inglês | MEDLINE | ID: mdl-18757250

RESUMO

A simple, direct and accurate method for the determination of concentration and enrichment of free fatty acids (FFAs) in human plasma was developed. The validation and comparison to a conventional method are reported. Three amide derivatives, dimethyl, diethyl and pyrrolidide, were investigated in order to achieve optimal resolution of the individual fatty acids. This method involves the use of dimethylamine/Deoxo-Fluor to derivatize plasma free fatty acids to their dimethylamides. This derivatization method is very mild and efficient, and is selective only towards FFAs so that no separation from a total lipid extract is required. The direct method gave lower concentrations for palmitic acid and stearic acid and increased concentrations for oleic acid and linoleic acid in plasma as compared to methyl ester derivative after thin-layer chromatography. The [(13)C]palmitate isotope enrichment measured using direct method was significantly higher than that observed with the BF(3)/MeOH-TLC method. The present method provided accurate and precise measures of concentration as well as enrichment when analyzed with gas chromatography combustion-isotope ratio-mass spectrometry.


Assuntos
Cromatografia Gasosa/métodos , Ácidos Graxos não Esterificados/sangue , Espectrometria de Massas/métodos , Isótopos de Carbono , Ácidos Graxos não Esterificados/isolamento & purificação , Humanos , Marcação por Isótopo/métodos , Incerteza
12.
Bioresour Technol ; 99(16): 7438-43, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18387298

RESUMO

The removal of free fatty acid (FFA) in waste frying oil by esterification with methanol was conducted using various zeolite catalysts. The ZSM-5 (MFI), mordenite (MOR), faujasite (FAU), beta (BEA) zeolites, and silicalite were employed with different Si/Al molar ratio in the reaction. The effects of acidic properties and pore structure of the zeolite catalysts were discussed relating to the conversion of the FFA. The MFI zeolite induced an improvement of the removal efficiency of FFA by cracking to the FFA in its pore structure due to its narrow pore mouth. The catalytic activity for FFA removal was lowered with decreasing of acid strength of the zeolites. The strong acid sites of zeolites induced the high conversion of FFA comparatively. The acid strength and pore structure of acidic zeolites affected the catalytic activity in FFA removal.


Assuntos
Ácidos Graxos não Esterificados/isolamento & purificação , Metanol/química , Óleos/química , Zeolitas/química , Adsorção , Catálise , Esterificação , Concentração de Íons de Hidrogênio , Temperatura , Difração de Raios X , Zeolitas/classificação
13.
Biomolecules ; 8(4)2018 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-30551655

RESUMO

Matrix-assisted laser desorption/ionization (MALDI) is one of the most successful "soft" ionization methods in the field of mass spectrometry and enables the analysis of a broad range of molecules, including lipids. Although the details of the ionization process are still unknown, the importance of the matrix is commonly accepted. Both, the development of and the search for useful matrices was, and still is, an empirical process, since properties like vacuum stability, high absorption at the laser wavelength, etc. have to be fulfilled by a compound to become a useful matrix. This review provides a survey of successfully used MALDI matrices for the lipid analyses of complex biological samples. The advantages and drawbacks of the established organic matrix molecules (cinnamic or benzoic acid derivatives), liquid crystalline matrices, and mixtures of common matrices will be discussed. Furthermore, we will deal with nanocrystalline matrices, which are most suitable to analyze small molecules, such as free fatty acids. It will be shown that the analysis of mixtures and the quantitative analysis of small molecules can be easily performed if the matrix is carefully selected. Finally, some basic principles of how useful matrix compounds can be "designed" de novo will be introduced.


Assuntos
Ácidos Graxos não Esterificados/isolamento & purificação , Lipídeos/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/tendências , Ácidos Graxos não Esterificados/química , Lipídeos/química , Cristais Líquidos/química , Vácuo
14.
J Oleo Sci ; 67(11): 1373-1379, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30404957

RESUMO

Pinolenic acid (PLA), which is a fatty acid (FA) exclusively found in the oils of edible pine nuts, has an appetite-suppression effect, thereby being effective to reduce body weight in humans. PLA concentrates would be suitable for use in functional foods and nutraceuticals due to the health benefits of PLA. PLA concentrates were prepared from free FA (FFA) obtained from pine nut oil using solvent fractionation. Siberian pine nut oil containing 18.3 wt% PLA was used as the starting material for the fractionation. The fractionation was performed in n-hexane at ultra-low temperatures down to -85°C. The PLA concentrates produced under the optimal conditions established in this study (temperature, -85°C; n-hexane-to-FFA ratio (v/w), 30:1; fractionation time, 36 h) contained 69.8 wt% PLA. The yield of PLA was 77.4 wt% of the initial PLA weight in the FFA. These results suggest that solvent fractionation is a more effective approach to prepare PLA concentrates with higher PLA contents at a particular yield of PLA than published methods using urea crystallization (e.g., PLA content = ~47 wt%, yield of PLA = ~77 wt%, Woo et al. (2016)) or lipase-catalyzed reactions (e.g., PLA content = ~30 wt%, yield of PLA = ~61 wt%, Lee et al. (2011)). The resulting PLA concentrates contained 11 of the 12 different species of FA present in the FFA, thereby indicating that the PLA concentrates prepared by solvent fractionation have more diverse FA profiles than those prepared by urea crystallization (e.g., 7 species of FA, Woo et al. (2016)).


Assuntos
Depressores do Apetite/isolamento & purificação , Fracionamento Químico/métodos , Ácidos Graxos não Esterificados/química , Ácidos Graxos não Esterificados/isolamento & purificação , Hexanos , Ácidos Linolênicos/isolamento & purificação , Nozes/química , Pinus/química , Óleos de Plantas/química , Solventes , Temperatura Baixa
15.
PLoS One ; 13(5): e0196709, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29723222

RESUMO

Atrial fibrillation (AF) is the most common cardiac arrhythmia, and its incidence is increasing worldwide. One method used to restore sinus rhythm is direct current cardioversion (DCCV). Despite the high success rate of DCCV, AF typically recurs within the first 2 weeks. However, our understanding of the pathophysiology of AF recurrence, incidence, and progression are highly limited. Lipidomic profiling was applied to identify altered lipids in plasma from patients with AF using ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry coupled with multivariate statistical analysis. Partial least-squares discriminant analysis revealed a clear separation between AF patients and healthy controls. The levels of several lipid species, including fatty acids and phospholipids, were different between AF patients and healthy controls, indicating that oxidative stress and inflammation are associated with the pathogenesis of AF. Similar patterns were also detected between recurrent and non-recurrent AF patients. These results suggest that the elevated saturated fatty acid and reduced polyunsaturated fatty acid levels in AF patients may be associated with enhanced inflammation and that free fatty acid levels may play a crucial role in the development and progression of AF.


Assuntos
Fibrilação Atrial/sangue , Ácidos Graxos não Esterificados/sangue , Idoso , Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/terapia , Cromatografia Líquida/métodos , Cardioversão Elétrica , Ácidos Graxos/sangue , Ácidos Graxos/isolamento & purificação , Ácidos Graxos não Esterificados/isolamento & purificação , Feminino , Humanos , Inflamação , Interleucina-1beta/biossíntese , Interleucina-1beta/genética , Análise dos Mínimos Quadrados , Masculino , Espectrometria de Massas/métodos , Pessoa de Meia-Idade , Fosfolipídeos/sangue , Fosfolipídeos/isolamento & purificação , Plasma , RNA Mensageiro/biossíntese , Recidiva , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/genética
16.
J Clin Invest ; 74(4): 1269-79, 1984 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6548228

RESUMO

The surfactant fraction (55,000-g pellet) of leukocyte-free rat bronchoalveolar lavage fluid contains factors that rapidly kill and lyse pneumococci. These factors were purified and identified biochemically by using a quantitative bactericidal test to monitor fractionation procedures. 91% of the antipneumococcal activity of rat surfactant was recovered in chloroform after extraction of rat surfactant with chloroform-methanol (Bligh-Dyer procedure). After chromatography on silicic acid with chloroform, acetone, and methanol, all detectable antibacterial activity (approximately 80% of the initial activity) eluted with the neutral lipids in chloroform. When rechromatographed on silicic acid with hexane, hexane-chloroform, and chloroform, the antibacterial activity eluted with FFA. Thin-layer chromatography (TLC) established that the antibacterial activity was confined to the FFA fraction. Gas-liquid chromatography showed that the fatty acid fraction contained a mixture of long-chain FFA (C12 to C22) of which 66.7% were saturated and 32.4% were unsaturated. The quantity of TLC-purified FFA needed to kill 50% of 10(8) pneumococci under standardized conditions (one bactericidal unit) was 10.6 +/- 0.5 micrograms. Purified FFA acted as detergents, causing release of [3H]choline from pneumococcal cell walls and increased bacterial cell membrane permeability, evidenced by rapid unloading of 3-O-[3H]methyl-D-glucose. FFA acting as detergents appear to account for the bactericidal and bacteriolytic activity of rat pulmonary surfactant for pneumococci.


Assuntos
Antibacterianos , Proteolipídeos/isolamento & purificação , Alvéolos Pulmonares/fisiologia , Surfactantes Pulmonares/isolamento & purificação , Animais , Bacteriólise , Permeabilidade da Membrana Celular/efeitos dos fármacos , Cães , Ácidos Graxos não Esterificados/isolamento & purificação , Ácidos Graxos não Esterificados/farmacologia , Cobaias , Lipólise , Masculino , Proteolipídeos/fisiologia , Proteínas Associadas a Surfactantes Pulmonares , Surfactantes Pulmonares/fisiologia , Ratos , Ratos Endogâmicos , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pneumoniae/crescimento & desenvolvimento , Irrigação Terapêutica
17.
J Chromatogr A ; 1169(1-2): 77-85, 2007 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-17869260

RESUMO

A new fluorescein-based fluorescent derivatizating reagent, 6-oxy-(acetyl piperazine) fluorescein (APF), has been designed, synthesized and developed for carboxylic acid labeling. It was used as a pre-column derivatizing reagent for the determination of seven free fatty acids (lauric acid, myristic acid, arachidonic acid, linoleic acid, palmitic acid, oleic acid, and stearic acid) with high-performance liquid chromatography (HPLC). The derivatization reaction of APF with seven fatty acids was completed at 60 degrees C for 1 h using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) as the condensing reagent. On a C18 column, the derivatives of APF with seven free fatty acids could be separated completely in 22 min using a mobile phase of methanol-water (88:12, v/v) containing 7 mmol L(-1) pH 6.5 Na2HPO4-H3Cit3 buffer with fluorescence detection at lambdaex/lambdaem=467/512 nm. The detection limits could reach 0.1-6.4 nmol L(-1) (signal-to-noise=3). This reagent was applied to the determination of the free fatty acids in human serum samples with satisfying recovery efficiencies varying from 93 to 105%.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Ácidos Graxos não Esterificados/isolamento & purificação , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Espectrometria de Fluorescência/métodos , Ácidos Carboxílicos/sangue , Ácidos Carboxílicos/química , Cromatografia Líquida de Alta Pressão/instrumentação , Ácidos Graxos não Esterificados/química , Fluoresceínas , Humanos , Interações Hidrofóbicas e Hidrofílicas , Piperazinas , Sensibilidade e Especificidade , Manejo de Espécimes/métodos , Espectrometria de Fluorescência/instrumentação
18.
Plant Physiol Biochem ; 45(3-4): 250-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17360190

RESUMO

In order to develop a sensitive and reliable method for FFA quantification in lipid matrices of seeds, two SPE procedures employed in meat and dairy chemistry were compared using a 100/1 mixture of triolein/heptadecanoic acid. The overall efficiency of the SPE procedure retained was satisfactory since it allowed removal of 99.8% of triacylglycerols (TAG) and recovery of 99.2% of FFA as quantified by gas chromatography of fatty acid methyl esters (FAME). However, the low amount of TAG eluted in the FFA fraction represented a non-negligible percentage (17%) of FAME and the procedure thus required further improvement. TAG pollution was successively decreased to 12%, 8% and finally 1.5% by: i) modifying the volume of elution of TAG; ii) removing the saponification step initially performed according to the standard FAME procedure; and iii) reducing the duration of the BF(3)-catalyzed methylation reaction to 1 min. The new SPE/methylation procedure described here was then compared to the most widely used method for FFA measurement in plants which is based on thin-layer chromatography (TLC). Both procedures were applied to coffee seeds stored for 0-18 months at 15 degrees C under 62% relative humidity and provided consistent results. A very clear negative correlation was observed between the loss of seed viability and the accumulation of FFA in seeds during the course of storage independent of the method employed for FFA quantification. However, we demonstrated that the TLC/on-silica methylation procedure underestimates FFA contents in comparison with the new SPE/methylation procedure because of a selective loss of unsaturated FA.


Assuntos
Ácidos Graxos não Esterificados/análise , Lipídeos/química , Sementes/química , Extração em Fase Sólida/métodos , Cromatografia em Camada Fina , Café/química , Ácidos Graxos não Esterificados/química , Ácidos Graxos não Esterificados/isolamento & purificação , Metilação , Reprodutibilidade dos Testes , Sementes/metabolismo
19.
Anal Chim Acta ; 962: 41-51, 2017 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-28231879

RESUMO

This work proposes a new vacuum headspace solid-phase microextraction (Vac-HSSPME) method combined to gas chromatography-flame ionization detection for the determination of free fatty acids (FFAs) and phenols. All target analytes of the multicomponent solution were volatiles but their low Henry's Law constants rendered them amenable to Vac-HSSPME. The ability of a new and easy to construct Vac-HSSPME sampler to maintain low-pressure conditions for extended sampling times was concurrently demonstrated. Vac-HSSPME and regular HSSPME methods were independently optimized and the results were compared at all times. The performances of four commercial SPME fibers and two polymeric ionic liquid (PIL)-based SPME fibers were evaluated and the best overall results were obtained with the adsorbent-type CAR/PDMS fiber. For the concentrations used here, competitive displacement became more intense for the smaller and more volatile analytes of the multi-component solution when lowering the sampling pressure. The extraction time profiles showed that Vac-HSSPME had a dramatic positive effect on extraction kinetics. The local maxima of adsorbed analytes recorded with Vac-HSSPME occurred faster, but were always lower than that with regular HSSPME due to the faster analyte-loading from the multicomponent solution. Increasing the sampling temperature during Vac-HSSPME reduced the extraction efficiency of smaller analytes due to the enhancement in water molecule collisions with the fiber. This effect was not recorded for the larger phenolic compounds. Based on the optimum values selected, Vac-HSSPME required a shorter extraction time and milder sampling conditions than regular HSSPME: 20 min and 35 °C for Vac-HSSPME versus 40 min and 45 °C for regular HSSPME. The performance of the optimized Vac-HSSPME and regular HSSPME procedures were assessed and Vac-HSSPME method proved to be more sensitive, with lower limits of detection (from 0.14 to 13 µg L-1), and better intra-day precision (relative standard deviations values < 10% at the lowest spiked level) than regular HSSPME for almost all target analytes. The proposed Vac-HSSPME method was successfully applied to quantify FFAs and phenols in milk and milk derivatives samples.


Assuntos
Ácidos Graxos não Esterificados/análise , Ácidos Graxos não Esterificados/isolamento & purificação , Fenóis/análise , Fenóis/isolamento & purificação , Microextração em Fase Sólida/métodos , Adsorção , Animais , Ácidos Graxos não Esterificados/química , Leite/química , Fenóis/química , Temperatura , Fatores de Tempo , Vácuo , Volatilização
20.
J Oleo Sci ; 66(5): 425-434, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28381770

RESUMO

Current work aims to develop a refining process for removing phospholipids, free fatty acids (FFA), and metal ions without affecting n-3 polyunsaturated fatty acid (n-3 PUFA) esters present in the crude Indian sardine oil. Sardine oil was subjected to degumming with various acids (orthophosphoric acid, acetic acid, and lactic acid), conventional and membrane assisted deacidification using various solvents (methanol, ethanol, propanol and butanol) and bleaching with bleaching agents (GAC, activated earth and bentonite) and all the process parameters were further optimized. Degumming with 5%(w/w) ortho phosphoric acid, two stage solvent extraction with methanol at 1:1 (w/w) in each stage and bleaching with 3% (w/w) activated charcoal loading, at 80ºC for 10 minutes resulted in the reduction of phospholipid content to 5.66 ppm from 612.66 ppm, FFA to 0.56% from 5.64% with the complete removal of iron and mercury. Under these conditions, the obtained bleached oil showed an enhancement of n-3 PUFA from 16.39 % (11.19 Eicosapentaenoic acid (EPA) + 5.20 Docosahexaenoic acid (DHA)) to 17.91 % (11.81 EPA + 6.1 DHA). Replacing conventional solvent extraction with membrane deacidification using microporous, hydrophobic polytetrafluoroethylene membrane (PTFE), resulted in a lesser solvent residue (0.25% (w/w)) in the deacidified oil. In view of lack of reports on refining of n-3 PUFA rich marine oils without concomitant loss of n-3 PUFA, this report is significant.


Assuntos
Ésteres/análise , Ácidos Graxos Ômega-3/análise , Óleos de Peixe/análise , Óleos de Peixe/química , Clareadores , Carvão Vegetal , Ácidos Graxos não Esterificados/isolamento & purificação , Íons , Compostos de Ferro/isolamento & purificação , Compostos de Mercúrio/isolamento & purificação , Fosfolipídeos/isolamento & purificação , Ácidos Fosfóricos , Politetrafluoretileno , Solventes , Temperatura
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