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1.
Molecules ; 27(18)2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36144484

RESUMO

Moringa oleifera Lam (syn. M. ptreygosperma Gaertn.) leaves are globally acclaimed for their nutritional content and mitigation of malnutrition. In most impoverished rural communities including Limpopo, Mpumalanga and KwaZulu Natal of South Africa, powdered leaves of Moringa oleifera are applied as a nutritional supplement for readily available food such as porridge for malnourished children and even breast-feeding mothers. Widely practiced and admired is also the use of the plant seed in the do-it-yourself purification of water by rural South Africans. This study aimed at identifying the chemical and nutritional marker compounds present in South African Moringa oleifera seed oils using high resolution 1-2-dimension gas chromatography in order to give scientific validation to its uses in cosmetics and particularly in culinary practices. Results obtained from two-dimension tandem mass spectrometry chemical signature revealed over 250 compounds, five times more than those reported from one-dimension gas chromatography. Whereas previous reports from gas chromatography-mass spectrometry analysis reported oleic acid (70-78%) as the major compound from oil samples from other countries, M. oleifera seed oil from South Africa is marked by cis-13-octadeaconic acid with 78.62% and 41.9% as the predominant monounsaturated fatty acid in the hexane and dichloromethane extracts respectively. This was followed by cis-vaccenic acid, an isomer of oleic acid at 51% in the acetone extract, 9-octadecanoic acid-(z)-methyl ester at 39.18%, 21.34% and 10.06% in dichloromethane, hexane and acetone extracts respectively. However, a principal component analysis with R2 = 0.98 of the two-dimension tandem mass spectrometry cum chemometric analysis indicated n-hexadecanoic acid, oleic acid, 9-octadecanoic acid-(z)-methyl ester and cis-vaccenic acid with a probability of 0.96, 0.88, 0.80 and 0.79 respectively as the marker compounds that should be used for the quality control of moringa seed oils from South Africa. This study demonstrates that South African Moringa oleifera oils contain C-18 monounsaturated fatty acids similar to oils from Egypt (76.2%), Thailand (71.6%) and Pakistan (78.5%) just to mention but a few. These fatty acids are sunflower and olive oil type-compounds and therefore place moringa seed oil for consideration as a cooking oil amongst its other uses.


Assuntos
Moringa oleifera , Moringa , Acetona/análise , Criança , Ésteres/análise , Ácidos Graxos/análise , Cromatografia Gasosa-Espectrometria de Massas , Hexanos , Humanos , Cloreto de Metileno , Moringa oleifera/química , Ácido Oleico/análise , Azeite de Oliva/análise , Ácido Palmítico/análise , Extratos Vegetais/química , Óleos de Plantas/química , Sementes/química , África do Sul , Ácidos Esteáricos/análise , Água/análise
2.
Molecules ; 26(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34361739

RESUMO

We developed an alternative whipping cream fat using shea butter but with low saturation. Enriched stearic-oleic-stearic (SOS) solid fat was obtained from shea butter via solvent fractionation. Acyl migration reactant, which mainly contains asymmetric SSO triacylglycerol (TAG), was prepared through enzymatic acyl migration to obtain the creaming quality derived from the ß'-crystal form. Through enzymatic acyl migration, we obtained a 3.4-fold higher content of saturated-saturated-unsaturated (SSU) TAG than saturated-unsaturated-saturated (SUS) TAG. The acyl migration reactant was refined to obtain refined acyl migration reactant (RAMR). An alternative fat product was prepared by blending RAMR and hydrogenated palm kernel oil (HPKO) at a ratio of 4:6 (w/w). The melting points, solid fat index (SFI), and melting curves of the alternative products were similar to those of commercial whipping cream fat. The alternative fat had a content of total unsaturated fatty acids 20% higher than that of HPKO. The atherogenic index (AI) of alternative fat was 3.61, much lower than those of whipping cream fat (14.59) and HPKO (1220.3), because of its low atherogenic fatty acid content and high total unsaturated fatty acids. The polymorphic crystal form determined by X-ray diffraction spectroscopy showed that the ß'-crystal form was predominant. Therefore, the alternative fat is comparable with whipping cream that requires creaming quality, and has a reduced saturated fat content.


Assuntos
Gorduras na Dieta/análise , Ácidos Graxos Insaturados/química , Tecnologia de Alimentos/métodos , Ácidos Oleicos/química , Óleos de Plantas/química , Fracionamento Químico , Cristalização , Ácidos Graxos Insaturados/análise , Humanos , Ácido Oleico/análise , Ácido Oleico/química , Ácidos Oleicos/análise , Óleo de Palmeira/análise , Óleo de Palmeira/química , Óleos de Plantas/análise , Ácidos Esteáricos/análise , Ácidos Esteáricos/química , Triglicerídeos/análise , Triglicerídeos/química
3.
Bioorg Med Chem ; 42: 116254, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34119697

RESUMO

Microbes use signaling factors for intraspecies and interspecies communications. While many intraspecies signaling factors have been found and characterized, discovery of factors for interspecies communication is lagging behind. To facilitate the discovery of such factors, we explored the potential of a mixed microbial culture (MMC) derived from wheatgrass, in which heterogeneity of this microbial community might elicit signaling factors for interspecies communication. The stability of Wheatgrass MMC in terms of community structure and metabolic output was first characterized by 16S ribosomal RNA amplicon sequencing and liquid chromatography/mass spectrometry (LC/MS), respectively. In addition, detailed MS analyses led to the identification of 12-hydroxystearic acid (12-HSA) as one of the major metabolites produced by Wheatgrass MMC. Stereochemical analysis revealed that Wheatgrass MMC produces mostly the (R)-isomer, although a small amount of the (S)-isomer was also observed. Furthermore, 12-HSA was found to modulate planktonic growth and biofilm formation of various marine bacterial strains. The current study suggests that naturally derived MMCs could serve as a simple and reproducible platform to discover potential signaling factors for interspecies communication. In addition, the study indicates that hydroxylated long-chain fatty acids, such as 12-HSA, may constitute a new class of interspecies signaling factors.


Assuntos
Alteromonas/citologia , Caulobacteraceae/citologia , Técnicas de Cultura de Células , Plantas/microbiologia , Ácidos Esteáricos/análise , Alteromonas/isolamento & purificação , Alteromonas/metabolismo , Biofilmes , Caulobacteraceae/metabolismo , Cromatografia Líquida , Espectrometria de Massas , Estrutura Molecular , Ácidos Esteáricos/metabolismo
4.
J Sep Sci ; 44(16): 3041-3051, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34101991

RESUMO

Chlorella vulgaris is a popular microalga used for biofuel production; nevertheless, it possesses a strong cell wall that hinders the extraction of molecules, especially lipids within the cell wall. For tackling this issue, we developed an efficient and cost-effective method for optimal lipid extraction. Microlaga cell disruption by acid hydrolysis was investigated comparing different temperatures and reaction times; after hydrolysis, lipids were extracted with n-hexane. The best recoveries were obtained at 140°C for 90 min. The microalgae were then analyzed by an untargeted approach based on liquid chromatography with high-resolution mass spectrometry, providing the tentative identification of 28 fatty acids. First, a relative quantification on the untargeted data was performed using peak area as a surrogate of analyte abundance. Then, a targeted quantitative method was validated for the tentatively identified fatty acids, in terms of recovery (78-100%), intra- and interday relative standard deviations (<10 and <9%, respectively) and linearity (R2  > 0.98). The most abundant fatty acids were palmitic, palmitoleic, oleic, linoleic, linolenic, and stearic acids.


Assuntos
Chlorella vulgaris/metabolismo , Cromatografia Líquida/métodos , Ácidos Graxos/química , Espectrometria de Massas/métodos , Microalgas/metabolismo , Biocombustíveis/análise , Biomassa , Calibragem , Ácidos Graxos Monoinsaturados/análise , Hexanos/química , Hidrólise , Ácido Linoleico/análise , Lipídeos/química , Ácido Oleico/análise , Ácido Palmítico/análise , Reprodutibilidade dos Testes , Ácidos Esteáricos/análise , Temperatura , Ácido alfa-Linolênico/análise
5.
J Med Chem ; 64(9): 5654-5666, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33881857

RESUMO

The discovery of novel bioactive lipids that promote human health is of great importance. Combining "suspect" and targeted lipidomic liquid chromatography-high-resolution mass spectrometry (LC-HRMS) approaches, a previously unrecognized class of oxidized fatty acids, the saturated oxo fatty acids (SOFAs), which carry the oxo functionality at various positions of the long chain, was identified in human plasma. A library of SOFAs was constructed, applying a simple green photochemical hydroacylation reaction as the key synthetic step. The synthesized SOFAs were studied for their ability to inhibit in vitro the cell growth of three human cancer cell lines. Four oxostearic acids (OSAs) were identified to inhibit the cell growth of human lung carcinoma A549 cells. 6OSA and 7OSA exhibited the highest cell growth inhibitory potency, suppressing the expression of both STAT3 and c-myc, which are critical regulators of cell growth and proliferation. Thus, naturally occurring SOFAs may play a role in the protection of human health.


Assuntos
Proliferação de Células/efeitos dos fármacos , Ácidos Graxos/química , Lipídeos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Regulação para Baixo/efeitos dos fármacos , Ácidos Graxos/metabolismo , Ácidos Graxos/farmacologia , Humanos , Lipídeos/química , Espectrometria de Massas , Oxirredução , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Ácidos Esteáricos/análise , Ácidos Esteáricos/metabolismo , Ácidos Esteáricos/farmacologia
6.
Neuromolecular Med ; 23(1): 161-175, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33475971

RESUMO

Alzheimer's disease (AD) is a progressive and incurable brain disorder that has been associated with structural changes in brain phospholipids (PLs), including diacyl species and ether-linked PLs known as plasmalogens. Most studies have characterized total changes in brain PL pools (e.g., choline plasmalogens), particularly in prefrontal cortex, but detailed and quantitative information on the molecular PL species impacted by the disease is limited. In this study, we used a comprehensive mass-spectrometry method to quantify diacyl and plasmalogen species, alkyl synthetic precursors of plasmalogens, and lysophospholipid degradation products of diacyl and plasmalogen PLs, in postmortem samples of prefrontal cortex from 21 AD patients and 20 age-matched controls. Total PLs were also quantified with gas-chromatography analysis of bound fatty acids following thin layer chromatography isolation. There was a significant 27% reduction in the concentration (nmol/g wet weight) of choline plasmalogen containing stearic acid (alkenyl group) and docosahexaenoic acid in AD compared to controls. Stearic acid concentration in total PLs was reduced by 26%. Our findings suggest specific changes in PLs containing stearic acid and docosahexaenoic acid in AD prefrontal cortex, highlighting structural and turnover PL pathways that could be targeted.


Assuntos
Doença de Alzheimer/metabolismo , Ácidos Docosa-Hexaenoicos/análise , Lipidômica , Plasmalogênios/análise , Mudanças Depois da Morte , Córtex Pré-Frontal/química , Ácidos Esteáricos/análise , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Cromatografia Líquida de Alta Pressão , Ácidos Graxos/análise , Feminino , Humanos , Lisofosfolipídeos/metabolismo , Masculino , Modelos Moleculares , Fosfolipídeos/análise , Espectrometria de Massas em Tandem
7.
J Food Sci ; 85(9): 2665-2672, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32839966

RESUMO

Five fatty acids comprise the bulk of the lipid content in pecans: palmitic acid, stearic acid, oleic acid, linoleic acid, and linolenic acid. Understanding the profiles of these fatty acids and how they relate to sensory characteristics may offer an explanation for flavor and flavor defects that may exist in certain cultivars of pecans. The objective of this study was to examine and compare fatty acid profiles of three cultivars of pecans (Major, Lakota, and Chetopa), over two crop years, under raw and roasted preparation methods, and understand the fatty acids association with sensory attributes. Percentages of palmitic, stearic, oleic, linoleic, and linolenic acids to total fatty acid content were determined using gas chromatography, and sensory profiles were generated using descriptive sensory analysis. Similar trends were seen across samples, with oleic acid comprising the majority of the total fatty acids and linolenic acid comprising the smallest percentage. There were significant differences in fatty acid content among cultivars and between pecans in the first and second crop year. Few associations were found between the fatty acids and sensory attributes, which suggest that combinations of the fatty acids contribute to certain pleasant or undesirable flavor attributes in the pecans. Subtle differences in fatty acid composition may lead to variation in flavor and flavor intensity or draw attention to or from certain attributes during consumption. Differences in crop year indicated that fatty acid content and therefore flavor are variable year to year. PRACTICAL APPLICATION: This study will help understand how fatty acid content of pecans varies from year to year. This should be taken into account when manufacturing products with pecans as the nutritional content of the product may change as the result.


Assuntos
Carya/química , Ácidos Graxos/química , Carya/classificação , Cromatografia Gasosa , Culinária , Humanos , Ácido Linoleico/análise , Ácido Oleico/análise , Ácido Palmítico/análise , Sementes/química , Sementes/classificação , Ácidos Esteáricos/análise , Paladar , Ácido alfa-Linolênico/análise
8.
Int J Pharm ; 588: 119726, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32758592

RESUMO

This study investigates the performance of a sampling interface for monitoring cohesive, flowing powder formulations with Hausner's Ratio and Carr's Index higher than 1.5 and 35%, respectively. The sampler device was operated in combination with near-infrared (NIR) spectroscopy to quantify ibuprofen concentrations between 1.5 and 4.5% w/w. NIR spectra also provided essential information to study the process dynamics within the sampler. The 200 spectra per blend obtained demonstrated a continuous powder flow with no evidence of agglomerates or segregation within the sampler for a blend of 6 kg. A NIR calibration model was optimized to predict independent test blends, delivering root mean square error of predictions and bias under 0.1% w/w. The test blends were within specifications according to the requirements of European Pharmacopeia. Variographic analysis demonstrated that the sampler device may determine low drug concentration in cohesive powder blends, presenting sampling errors below 0.011 (%w/w)2. This analysis also demonstrated that an increase in the blend compressibility leads to a slight rise in sampling errors within the sampler device. The sampler device offers statistical robustness in the evaluation of blend uniformity, providing greater confidence in the quality determination of the cohesive powder blends without significantly affecting its flow properties.


Assuntos
Excipientes/análise , Ibuprofeno/análise , Espectroscopia de Luz Próxima ao Infravermelho , Tecnologia Farmacêutica , Celulose/análise , Composição de Medicamentos , Excipientes/normas , Ibuprofeno/normas , Lactose/análise , Tamanho da Partícula , Pós , Controle de Qualidade , Espectroscopia de Luz Próxima ao Infravermelho/normas , Ácidos Esteáricos/análise , Tecnologia Farmacêutica/normas
9.
J Dairy Sci ; 103(10): 8967-8975, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32747096

RESUMO

Saturated fatty acid supplements commonly fed to dairy cows differ in their fatty acid (FA) profile. Some supplements with very high enrichments of palmitic acid (PA) or stearic acid (SA) have been reported to have low total-tract digestibility. Saturated FA have the potential to form crystalline structures at high purity that may affect digestibility. Differential scanning calorimetry (DSC) is a thermal technique commonly used in materials science to measure the change in heat flow as energy is absorbed or released from a sample during heating, and it was used to characterize a series of experimental and commercial fat supplements. Our hypothesis was that products with very high enrichment of either PA or SA would differ in thermal characteristics compared with those that include moderate levels of a second FA because of the formation of secondary crystalline structures, which may contribute to decreased digestibility. First, replicated runs demonstrated low variation in melting temperature (MT) and enthalpy (coefficient of variation <4%). The effect of physical form was evaluated by comparing an initial thermal cycle to a second, successive thermal cycle after samples had resolidified in the test pan. Melting temperature was slightly increased by 1.3°C by the second cycle compared with the first, but there was no change in enthalpy. Next, supplements with 98% SA, 98% PA, and an SA/PA (44%/55%) blend with undetectable levels of unsaturated FA were compared. Melting temperature of the SA/PA mixture was 61.2°C and similar to the expected MT of PA (62.9°C). However, the MT of the high-purity SA and PA were increased to 73.7°C and 67.8°C, respectively, and enthalpy increased by 12.5% compared with the SA/PA blend. An FA stock highly enriched in SA (>98%) had the highest MT, and one moderately enriched in PA (∼85%) that contained 10.1% unsaturated FA had the lowest enthalpy value of all FA supplements and experimental stocks that were characterized. Differential scanning calorimetry may be useful to screen and design supplements with improved physical properties that may be associated with digestibility.


Assuntos
Varredura Diferencial de Calorimetria/veterinária , Bovinos , Ácidos Graxos/química , Ácido Palmítico/análise , Ácidos Esteáricos/análise , Ração Animal/análise , Animais , Dieta/veterinária , Suplementos Nutricionais/análise , Digestão , Ácidos Graxos/análise , Feminino , Lactação/efeitos dos fármacos , Leite/química , Ácido Palmítico/química , Ácidos Esteáricos/química , Termodinâmica
10.
J Oleo Sci ; 69(3): 185-190, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32051358

RESUMO

In this study, the oil uptake and fatty acid composition of fried potato slices were determined. Some pre-treatments such as blanching, freezing, and blanching-freezing were applied to potato slices before frying while the untreated samples were used as a control. The frying process was carried out in sunflower and olive oils. The percentage oil uptake in slices varied from 4.26% to 10.35% when fried in sunflower oil. In the case of the control samples slices fried in olive oil contained high monounsaturated fatty acid (oleic acid) content (5.45%), and lesser oil uptake was observed than those processed in sunflower oil, which is rich in polyunsaturated fatty acid (linoleic acid is 5.99%) (p < 0.05). The oil uptake was also compared in the case of potato slices fried in two different oils after pre-treatments. The maximum oil uptake was observed in the case of blanched-frozen potatoes, whereas minimum oil uptake was observed in frozen only slices for both oils. The fatty acid contents in oils extracted from fried potato slices showed that the predominant fatty acids were palmitic, stearic, oleic, and linoleic acids. The best results were observed in frozen potato slices fried in both sunflower and olive oils.


Assuntos
Ácidos Graxos/análise , Azeite de Oliva , Solanum tuberosum/química , Óleo de Girassol , Culinária/métodos , Ácido Linoleico/análise , Ácido Oleico/análise , Azeite de Oliva/química , Ácido Palmítico/análise , Ácidos Esteáricos/análise , Óleo de Girassol/química
11.
Microbiologyopen ; 9(1): e00950, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31637873

RESUMO

Thraustochytrids have been isolated from different aquatic systems; however, few studies have reported their occurrence in Antarctica. In this study, 13 strains close to strains belonging to the genera Oblongichytrium, Thraustochytrium, and Aurantiochytrium were isolated from seawater samples collected near the Antarctic Base Professor Julio Escudero (S 62°12'57' E 58°57'35″). Docosahexaenoic acid (DHA) was found in the total lipids of all the isolates; DHA content of the biomass (dry weight) varied between 3.3 and 33 mg/g under the growth conditions for isolation. Five of the Antarctic thraustochytrids were able to accumulate lipids at levels higher than 20% w/w. Two strains, RT2316-7 and RT2316-13, were selected to test the effect of the incubation temperature (at 5°C for 14 days and at 15°C for 5 days). Incubation temperature had little effect on the lipid content and biomass yield; however, its effect on the fatty acid composition was significant (p < .05). The low incubation temperature favored the accumulation of eicosapentaenoic acid (EPA), palmitic acid and stearic acid in the total lipids of RT2316-7. Percentage of EPA, DHA and the omega-6 fatty acid dihomo-γ-linolenic acid of total fatty acids of RT2316-13 was higher at the low incubation temperature. RT2316-13 accumulated the highest lipid content (30.0 ± 0.5%) with a carbon to nitrogen mass ratio equal to 16.9. On the contrary, lipid accumulation in RT2316-7 occurred at high concentration of the nitrogen sources (monosodium glutamate or yeast extract). The capability to accumulate lipids with a fatty acid profile that can be tuned through cultivation temperature make the Antarctic thraustochytrid RT2316-13 a candidate for the production of lipids with different uses.


Assuntos
Reatores Biológicos/microbiologia , Ácidos Graxos Ômega-3/biossíntese , Estramenópilas/metabolismo , Ácido 8,11,14-Eicosatrienoico/análise , Regiões Antárticas , Membrana Celular/fisiologia , Ácidos Docosa-Hexaenoicos/análise , Ácido Eicosapentaenoico/análise , Ácido Palmítico/análise , Água do Mar , Ácidos Esteáricos/análise , Estramenópilas/classificação , Estramenópilas/crescimento & desenvolvimento , Estramenópilas/isolamento & purificação , Temperatura
12.
Sci Rep ; 9(1): 10941, 2019 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-31358890

RESUMO

In the present work, linoleic acid and oleic acid were isolated from Indonesian corn oil and palm oil and they were used to prepare monoacylglycerol derivatives as the antibacterial agent. Indonesian corn oil contains 57.74% linoleic acid, 19.88% palmitic acid, 11.84% oleic acid and 3.02% stearic acid. While Indonesian palm oil contains 44.72% oleic acid, 39.28% palmitic acid, 4.56% stearic acid and 1.54% myristic acid. The oleic acid was purified by using Urea Inclusion Complex (UIC) method and its purity was significantly increased from 44.72% to 94.71%. Meanwhile, with the UIC method, the purity of ethyl linoleate was increased from 57.74% to 72.14%. 1-Monolinolein and 2-monoolein compounds were synthesized via two-step process from the isolated linoleic acid and oleic acid, respectively. The preliminary antibacterial assay shows that the 1-monolinolein did not give any antibacterial activity against Staphylococcus aureus and Escherichia coli, while 2-monoolein showed weak antibacterial activity against Staphylococcus aureus.


Assuntos
Anti-Infecciosos/síntese química , Óleo de Milho/química , Glicerídeos/síntese química , Óleo de Palmeira/química , Anti-Infecciosos/farmacologia , Escherichia coli/efeitos dos fármacos , Glicerídeos/farmacologia , Ácidos Linoleicos/análise , Ácidos Oleicos/análise , Ácido Palmítico/análise , Staphylococcus aureus/efeitos dos fármacos , Ácidos Esteáricos/análise , Ureia/química
13.
Artigo em Inglês | MEDLINE | ID: mdl-31229913

RESUMO

Two simplified methods based on manual thermally-assisted hydrolysis and methylation (THM) GC and GC × GC with flame ionization detection (FID) were developed for the detection of mycobacteria and Mycobacterium tuberculosis (MTB) in sputum. A central composite design was employed to optimize the THM derivatization conditions. For the detection of MTB the known mycobacterial markers tuberculostearic acid (TBSA) and hexacosanoic acid (C26), as well as three MTB specific markers, the mycocerosates, were evaluated. We found that the optimum conditions for THM release of TBSA and C26 differ from those for maximum release of the mycocerosates. Higher reagent volumes, higher temperatures and longer incubation increase the mycocerosates yield. Application of these conditions unfortunately resulted in unacceptable safety hazards. A GC × GC-FID method was developed that allowed accurate detection of mycocerosates even at poor conversion yields of the derivatization reaction. Using spiked sputum samples from non-TB patients, the detection limit of the method based on TBSA and C26 was found to be comparable to that of microscopy, i.e. 104-105 bacteria/mL sputum. To validate the new test, we compared the results we found for fifteen sputum samples from patients from South Africa suspected of having tuberculosis with those of culture, the gold standard method. Based on the presence of TBSA and C26, all eight microscopy and culture positive samples, and even two microscopy negative but culture positive samples were positive by THM-GC-FID. All five microscopy and culture negative sputum samples were also negative for THM-GC-FID, giving a specificity of 100%. Using GC × GC-FID we could detect mycocerosates, the specific markers for MTB in seven out of ten MTB culture positive sputum samples. The five culture negative cases were also negative for mycocerosates in manual THM-GC × GC-FID giving again 100% specificity. The results obtained indicate that the new methods hold great potential for the early diagnosis of TB in developing countries.


Assuntos
Cromatografia Gasosa/métodos , Testes Diagnósticos de Rotina/métodos , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Pulmonar/diagnóstico , Cromatografia Gasosa/instrumentação , Ácidos Graxos/análise , Ácidos Graxos/metabolismo , Humanos , Limite de Detecção , Mycobacterium tuberculosis/química , Mycobacterium tuberculosis/metabolismo , Sensibilidade e Especificidade , Escarro/microbiologia , Ácidos Esteáricos/análise , Ácidos Esteáricos/metabolismo , Tuberculose Pulmonar/microbiologia
14.
Methods Mol Biol ; 2009: 13-33, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31152392

RESUMO

The use of synthetically synthesized azide and alkyne fatty acid analogs coupled with bioorthogonal Cu(I)-catalyzed Huisgen 1,3-dipolar cycloaddition reaction-based detection methods to study protein S-acylation reactions has replaced the traditional method of using in vivo metabolic radiolabeling with tritiated palmitic acid and has greatly facilitated our understanding of this essential cellular process. Here, we describe the chemical synthesis of myristic (C:14), palmitic (C16:0), and stearic (C18:0) acid-azide probes and detail how they may be utilized as chemical reporters for the analysis of S-acylation of exogenously expressed proteins in cells.


Assuntos
Ácido Mirístico/análise , Ácido Palmítico/análise , Proteína S/análise , Ácidos Esteáricos/análise , Acilação , Reação de Cicloadição , Células HEK293 , Humanos , Ácido Mirístico/metabolismo , Ácido Palmítico/metabolismo , Proteína S/metabolismo , Ácidos Esteáricos/metabolismo
15.
BMC Complement Altern Med ; 19(1): 113, 2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31159797

RESUMO

BACKGROUND: Embryonic neural stem cells (eNSCs) are immature precursors of the central nervous system (CNS), with self-renewal and multipotential differentiation capacities. These are regulated by endogenous and exogenous factors such as alpha-linolenic acid (ALA), a plant-based essential omega-3 polyunsaturated fatty acid. METHODS: In this study, we investigated the effects of various concentrations of Alyssum homolocarpum seed oil (AHSO), containing natural ALA, stearic acid (SA), myristic acid (MA), and ß-sitosterol, on proliferation and differentiation of eNSCs, in comparison to controls and to synthetic pure ALA. RESULTS: Treatment with natural AHSO (25 to 75 µM), similar to synthetic ALA, caused a significant ~ 2-fold increase in eNCSs viability, in comparison to controls. To confirm this proliferative activity, treatment of NSCs with 50 or 75 µM AHSO resulted in a significant increase in mRNA levels of notch1, hes-1 and Ki-67and NICD protein expression, in comparison to controls. Moreover, AHSO administration significantly increased the differentiation of eNSCs toward astrocytes (GFAP+) and oligodendrocytes (MBP+) in a dose dependent manner and was more potent than ALA, at similar concentrations, in comparison to controls. Indeed, only high concentrations of 100 µM AHSO, but not ALA, caused a significant increase in the frequency of neurons (ß-III Tubulin+). CONCLUSION: Our data demonstrated that AHSO, a rich source of ALA containing also other beneficial fatty acids, increased the proliferation and stimulated the differentiation of eNSCs. We suggest that AHSO's effects are caused by ß-sitosterol, SA and MA, present within this oil. AHSO could be used in diet to prevent neurodevelopmental syndromes, cognitive decline during aging, and various psychiatric disorders.


Assuntos
Brassicaceae/química , Células-Tronco Neurais/efeitos dos fármacos , Neurogênese/efeitos dos fármacos , Óleos de Plantas/farmacologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Antígeno Ki-67/metabolismo , Camundongos , Ácido Mirístico/análise , Células-Tronco Neurais/metabolismo , Óleos de Plantas/química , Sementes/química , Sitosteroides/análise , Ácidos Esteáricos/análise , Ácido alfa-Linolênico/análise
16.
J Pharm Biomed Anal ; 164: 528-535, 2019 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-30458386

RESUMO

To develop a robust quantitative calibration model for spectroscopy, different sources of variability that are not directly related to the components of interest should be included in the calibration samples; this variability should be similar to that which is anticipated during validation and routine operation. Moisture content of pharmaceutical samples can vary as a function of supplier, storage conditions, geographic origin or seasonal variation. Additionally, some pharmaceutical operations (e. g., wet granulation) cause exposure of excipients and API to water. Although water is a weak Raman scatterer, moisture variability has an indirect effect on analytical model performance. Because many pharmaceutical components have intrinsic fluorescent characteristics (with broad spectral features), moisture variability may cause spectral artifacts in the form of baseline variation associated with fluorescence quenching. This work investigates the deleterious effects of water quenching on quantitative prediction accuracy of a multivariate calibration algorithm for Raman spectroscopy. To demonstrate this, a formulation composed of acetaminophen, lactose, microcrystalline cellulose, HPMC and magnesium stearate was used. Tablets were manufactured using laboratory scale equipment. A full-factorial design was used to vary acetaminophen (5 levels), and excipient ratios (3 levels) to generate tablets for calibration and testing. Tablet moisture variation was introduced by placing samples in different humidity chambers. Significant spectral effects arising from fluorescence were identified in the Raman spectra and due to moisture variation: the fluorescence related spectral variability caused substantial degradation of the prediction performance for API. The work demonstrated that accounting for moisture variation during method development reduced the prediction error of the multivariate prediction model.


Assuntos
Acetaminofen/análise , Composição de Medicamentos/normas , Excipientes/análise , Umidade , Análise Espectral Raman/normas , Acetaminofen/administração & dosagem , Acetaminofen/química , Administração Oral , Calibragem , Celulose/análise , Celulose/química , Química Farmacêutica/métodos , Química Farmacêutica/normas , Composição de Medicamentos/métodos , Excipientes/química , Lactose/análise , Lactose/química , Modelos Químicos , Análise Espectral Raman/métodos , Ácidos Esteáricos/análise , Ácidos Esteáricos/química
17.
Clin Nutr ESPEN ; 23: 107-111, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29460784

RESUMO

BACKGROUND: Skin cancers are the most prevalent malignancy worldwide and Basal Cell Carcinoma (BCC) include the major type of nonmelanoma skin cancers. Fatty acids (FA) have a structural role in cell membranes and play an important role for many physiological and pathological immunologic pathways. Several prospective studies have been conducted on circulating fatty acids and the risk of prostate, breast and other cancers. The present study aimed to determine the saturated fatty acid composition differences of red blood cells (RBCs) in BCC patients and healthy control. METHODS: A hospital-based case-control study was conducted on new cases diagnosed of BCC patients. All subjects completed dietary recalls for dietary assessment. After fatty acids extraction, purification and preparation, gas chromatography was performed. The results were expressed in relative values (percent). RESULTS: Cases had lower RBC levels of Caproic acid (6:0) (P < 0.001), Caprylic acid (8:0) (P = 0.01), Capric acid (10:0) (P = 0.01), Palmitic acid (16:0) (P = 0.02) and higher RBC level of Pentadecanoic acid (15:0) (P = 0.04) and Stearic acid (18:0) (P = 0.01) compared with controls but did not differ in the level of the other primary saturated fatty acids. Saturation Index as defined by Stearic to Oleic acid ratio was significantly lower in BCC patients in comparison with Control group (P = 0.02). CONCLUSION: Here we showed that BCC patient had considerable differences in the SFA profiles in comparison with healthy subjects.


Assuntos
Carcinoma Basocelular/sangue , Membrana Eritrocítica/química , Ácidos Graxos/análise , Carcinoma Basocelular/diagnóstico , Estudos de Casos e Controles , Dieta , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ácido Palmítico/análise , Tamanho da Amostra , Ácidos Esteáricos/análise
18.
Food Res Int ; 105: 65-75, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29433259

RESUMO

The aim of the study was to identify new potential chemical markers of extra virgin olive oil (EVOO) quality by using a multicomponent analysis approach. Sixty-six EVOOs were purchased from the Italian market and classified according to their price as low price EVOOs (LEVOOs) and high price EVOOs (HEVOOs) costing 3.60-5.90euro/L and 7.49-29.80euro/L respectively. Sensory and chemical parameters strictly related to olive oil quality have been investigated, like volatile substances, polar phenolic substances, antioxidant activity, fatty acid composition, and α-tocopherol. Significant differences in terms of chemical composition and sensory features have been highlighted between the two EVOOs classes investigated, proving a generally lower level of quality of LEVOOs, clearly showed also by means of principal component analysis. Among the most interesting outcomes, R ratio (free tyrosol and hydroxytyrosol over total free and bound forms), measuring the extent of secoiridoids hydrolysis, resulted to be significantly higher in LEVOOs than in HEVOOs. Other key differences were found in the volatile substances composition, in the stearic acid percentage and in p-coumaric acid content.


Assuntos
Qualidade dos Alimentos , Azeite de Oliva/análise , Azeite de Oliva/química , Azeite de Oliva/economia , Aldeídos/análise , Antioxidantes/análise , Compostos de Bifenilo/análise , Ácidos Cumáricos/análise , Ácidos Graxos/análise , Humanos , Iridoides/análise , Itália , Olea/química , Azeite de Oliva/classificação , Fenóis/análise , Picratos/análise , Polifenóis/análise , Ácidos Esteáricos/análise , Tocoferóis/análise , alfa-Tocoferol/análise
19.
Biotechnol Bioeng ; 115(4): 932-942, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29313898

RESUMO

Chain length and degree of saturation plays an important role for the characteristics of various products derived from fatty acids, such as fuels, cosmetics, and food additives. The seeds of Theobroma cacao are the source of cocoa butter, a natural lipid of high interest for the food and cosmetics industry. Cocoa butter is rich in saturated fatty acids that are stored in the form of triacylglycerides (TAGs). One of the major TAG species of cocoa butter, consisting of two stearic acid molecules and one oleic acid molecule (stearic acid-oleic acid-stearic acid, sn-SOS), is particularly rare in nature as the saturated fatty acid stearic acid is typically found only in low abundance. Demand for cocoa butter is increasing, yet T. cacao can only be cultivated in some parts of the tropics. Alternative means of production of cocoa butter lipids (CBLs) are, therefore, sought after. Yeasts also store fatty acids in the form of TAGs, but these are typically not rich in saturated fatty acids. To make yeast an attractive host for microbial production of CBLs, its fatty acid composition needs to be optimized. We engineered Saccharomyces cerevisiae yeast strains toward a modified fatty acid synthesis. Analysis of the fatty acid profile of the modified strains showed that the fatty acid content as well as the titers of saturated fatty acids and the titers of TAGs were increased. The relative content of potential CBLs in the TAG pool reached up to 22% in our engineered strains, which is a 5.8-fold increase over the wild-type. SOS content reached a level of 9.8% in our engineered strains, which is a 48-fold increase over the wild type.


Assuntos
DNA Fúngico/genética , Gorduras na Dieta/metabolismo , Ácidos Oleicos/metabolismo , Saccharomyces cerevisiae/enzimologia , Ácidos Esteáricos/metabolismo , Acetiltransferases/genética , Acetiltransferases/metabolismo , Gorduras na Dieta/análise , Escherichia coli/genética , Engenharia Metabólica , Ácidos Oleicos/análise , Regiões Promotoras Genéticas/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Ácidos Esteáricos/análise , Estearoil-CoA Dessaturase/genética , Estearoil-CoA Dessaturase/metabolismo
20.
Nat Prod Res ; 32(4): 444-447, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28361553

RESUMO

The 2,2-diphenyl-1-picryl hydrazyl (DPPH) radical, nitric oxide, reducing power, hydrogen peroxide scavenging, and total antioxidant activities of the methanol extract, n-hexane, dichloromethane, ethyl acetate, butanol and aqueous fractions of the seed of Telfairia occidentalis were evaluated. Total phenolic content was determined using the Folin-Ciocalteu method. The dichloromethane fraction exhibited the highest DPPH radical scavenging, reducing power and total antioxidant activities. Two pure compounds which were identified by FTIR, H-and 2D NMR and Mass spectroscopy as 9-octadecenoic acid (TOS B) and 10-hydroxyoctadecanoic acid (TOS C) and four oily isolates, TOS A, TOS D, TOS E and TOS F were obtained from the dichloromethane fraction. TOS E had the highest DPPH radical scavening activity comparable to that of ascorbic acid. GC-MS analysis revealed the major compounds in TOS E as 4-(2,2-Dimethyl-6-methylene cyclohexylidene)-2-butanol; 3-(3-hydroxybutyl)-2,4,4-trimethyl-2-cyclohexene-1-one and 1,2-Benzenedicarboxylic acid disooctyl ester. Thus, the seed of T. occidentalis can be consumed for its antioxidant property.


Assuntos
Antioxidantes/química , Antioxidantes/farmacologia , Cucurbitaceae/química , Butanóis/química , Cromatografia Gasosa , Hexanos/química , Espectroscopia de Ressonância Magnética , Ácido Oleico/análise , Ácidos Oleicos , Fenóis/análise , Fenóis/química , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/farmacologia , Sementes/química , Espectroscopia de Infravermelho com Transformada de Fourier , Ácidos Esteáricos/análise , Ácidos Esteáricos/química
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