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1.
Anal Chim Acta ; 1273: 341537, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37423668

RESUMO

Despite the advances in low-field nuclear magnetic resonance (NMR), there are limited spectroscopic applications for untargeted analysis and metabolomics. To evaluate its potential, we combined high-field and low-field NMR with chemometrics for the differentiation between virgin and refined coconut oil and for the detection of adulteration in blended samples. Although low-field NMR has less spectral resolution and sensitivity compared to high-field NMR, it was still able to achieve a differentiation between virgin and refined coconut oils, as well as between virgin coconut oil and blends, using principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA), and random forest techniques. These techniques were not able to distinguish between blends with different levels of adulteration; however, partial least squares regression (PLSR) enabled the quantification of adulteration levels for both NMR approaches. Given the significant benefits of low-field NMR, including economic and user-friendly analysis and fitting in an industrial environment, this study establishes the proof of concept for its utilization in the challenging scenario of coconut oil authentication. Also, this method has the potential to be used for other similar applications that involve untargeted analysis.


Assuntos
Contaminação de Alimentos , Óleos de Plantas , Azeite de Oliva/análise , Óleo de Coco/análise , Contaminação de Alimentos/análise , Óleos de Plantas/análise , Espectroscopia de Ressonância Magnética
2.
Artigo em Inglês | MEDLINE | ID: mdl-36608113

RESUMO

The goal of this work was to investigate the impact of refining on coconut oil particularly on the most toxicologically relevant fraction of the mineral oil aromatic hydrocarbon (MOAH) contamination, namely the fraction composed by the three to seven aromatic rings. A fully integrated platform consisting of a liquid chromatography (LC), a comprehensive multidimensional gas chromatography (GC) (LC-GC × GC) and flame ionization detector (FID) was used to obtained a more detailed characterization of the MOAH sub-classes distribution. The revised EN pr 16995:2017-08 official method was used for preparing the samples, both with and without the auxiliary epoxidation step. Crude coconut oil was spiked with different MOAH standards, namely naphthalenes, alkylated naphthalenes, benzo(a)pyrene, and its alkylated homologues. Refining was modelled by deodorization at 230 °C, stripping with 10 kg/h of steam under 1 mbar vacuum for 3 h. Complete removal of the naphthalenes and reduction of more than 98.8% of the benzo(a)pyrenes was observed. Epoxidation had a significant impact on the MOAH fraction with more than three rings, but with a high dependency on the sample matrix, being significantly less evident in the refined samples than in the crude ones.


Assuntos
Hidrocarbonetos Aromáticos , Petróleo , Óleo Mineral/análise , Óleo de Coco/análise , Contaminação de Alimentos/análise , Hidrocarbonetos Aromáticos/análise , Cromatografia Gasosa/métodos , Petróleo/análise
3.
Int J Cosmet Sci ; 44(3): 289-298, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35377477

RESUMO

OBJECTIVE: The present study is intended to characterize the surfactant damage suffered by the hair cortex in routine washing and the mechanistic effect of Coconut Based Hair Oils (CBHO) to mitigate the damage. METHODS: Surfactants which diffuse into the hair structure solubilize protein moieties, leading to an increase in porosity and internal surface area as well as the pore volume. The changes in hair pores occurring in the hair cortex are measured by nitrogen sorption method in line with the Brunauer-Emmett-Teller (BET) theory. Single fiber tensile parameters were measured using Diastron MTT 175. Color protection was measured quantitatively using spectrophotometer as well as visual rating by trained panelists. RESULTS: The pore surface area data clearly show the benefit of introducing coconut-based hair oils (CBHO) into the hair by preventing increase in hair porosity. A statistically significant decrease in break stress and toughness were observed and the same were reversed by the application of CBHO. A pronounced color protection effect was also recorded with the application of CBHO. CONCLUSION: The porosity reduction effect seen with the use of CBHO is attributed to the CBHO molecules blocking the diffusion pathways in the endocuticle and the matrix part of the cortical cells, limiting protein surfactant interaction resulting in reduced solubilization and loss. Since, the color molecules are likely to be much smaller than the protein moieties, a pronounced color protection effect suggests that the penetrated CBHO molecules form a dense diffusion barrier in the matrix, cell membrane complex (CMC) and the endocuticle regions of hair - which are the main diffusion pathways out of hair. The study confirms the damage repair potential of CBHO and that it works by increasing the hydrophobicity of hair - both on the hair surface and in the cortex.


OBJECTIF: La présente étude a pour but de caractériser les dommages causés par les surfactants au cortex pilaire lors des lavages de routine et l'effet mécanique des huiles capillaires à base de noix de coco (CBHO) pour atténuer ces dommages. MÉTHODES: Les tensioactifs qui diffusent dans la structure du cheveu solubilisent les fractions de protéines, ce qui entraîne une augmentation de la porosité et de la surface interne ainsi que du volume des pores. Les modifications des pores du cheveu survenant dans le cortex pilaire sont mesurées par la méthode de sorption de l'azote, conformément à la théorie de Brunauer-Emmett-Teller (BET). Les paramètres de traction de la fibre unique ont été mesurés à l'aide du Diastron MTT 175. La protection de la couleur a été mesurée quantitativement en utilisant un spectrophotomètre ainsi qu'une évaluation visuelle par des panélistes formés. LES RÉSULTATS: Les données sur la surface des pores montrent clairement l'avantage d'introduire des huiles capillaires à base de noix de coco (CBHO) dans les cheveux en empêchant l'augmentation de la porosité des cheveux. Une diminution statistiquement significative de la contrainte de rupture et de la résistance a été observée, qui a été inversée par l'application de CBHO. Un effet prononcé de protection de la couleur a également été enregistré avec l'application de CBHO. LA CONCLUSION: L'effet de réduction de la porosité observé avec l'utilisation de CBHO est attribué aux molécules de CBHO bloquant les voies de diffusion dans l'endocuticule et la partie matricielle des cellules corticales, limitant l'interaction protéine surfactant résultant en une solubilisation et une perte réduite. Étant donné que les molécules de couleur sont probablement beaucoup plus petites que les parties protéiques, un effet prononcé de protection de la couleur suggère que les molécules CBHO pénétrées forment une barrière de diffusion dense dans la matrice, le complexe de la membrane cellulaire (CMC) et les régions endocuticulaires des cheveux - qui sont les principales voies de diffusion hors des cheveux. L'étude confirme le potentiel de réparation des dommages du CBHO et le fait qu'il agit en augmentant l'hydrophobie des cheveux - à la fois sur la surface du cheveu et dans le cortex.


Assuntos
Cocos , Cabelo , Óleo de Coco/análise , Óleo de Coco/metabolismo , Óleo de Coco/farmacologia , Cabelo/química , Porosidade , Tensoativos/análise
4.
N Engl J Med ; 382(8): 697-705, 2020 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-31860793

RESUMO

BACKGROUND: The causative agents for the current national outbreak of electronic-cigarette, or vaping, product use-associated lung injury (EVALI) have not been established. Detection of toxicants in bronchoalveolar-lavage (BAL) fluid from patients with EVALI can provide direct information on exposure within the lung. METHODS: BAL fluids were collected from 51 patients with EVALI in 16 states and from 99 healthy participants who were part of an ongoing study of smoking involving nonsmokers, exclusive users of e-cigarettes or vaping products, and exclusive cigarette smokers that was initiated in 2015. Using the BAL fluid, we performed isotope dilution mass spectrometry to measure several priority toxicants: vitamin E acetate, plant oils, medium-chain triglyceride oil, coconut oil, petroleum distillates, and diluent terpenes. RESULTS: State and local health departments assigned EVALI case status as confirmed for 25 patients and as probable for 26 patients. Vitamin E acetate was identified in BAL fluid obtained from 48 of 51 case patients (94%) in 16 states but not in such fluid obtained from the healthy comparator group. No other priority toxicants were found in BAL fluid from the case patients or the comparator group, except for coconut oil and limonene, which were found in 1 patient each. Among the case patients for whom laboratory or epidemiologic data were available, 47 of 50 (94%) had detectable tetrahydrocannabinol (THC) or its metabolites in BAL fluid or had reported vaping THC products in the 90 days before the onset of illness. Nicotine or its metabolites were detected in 30 of 47 of the case patients (64%). CONCLUSIONS: Vitamin E acetate was associated with EVALI in a convenience sample of 51 patients in 16 states across the United States. (Funded by the National Cancer Institute and others.).


Assuntos
Lesão Pulmonar Aguda/patologia , Líquido da Lavagem Broncoalveolar/química , Sistemas Eletrônicos de Liberação de Nicotina , Vaping/efeitos adversos , Vitamina E/análise , Lesão Pulmonar Aguda/etiologia , Adolescente , Adulto , Idoso , Fumar Cigarros , Óleo de Coco/análise , Feminino , Humanos , Limoneno/análise , Masculino , Pessoa de Meia-Idade , Estados Unidos , Adulto Jovem
5.
Artigo em Inglês | MEDLINE | ID: mdl-31593521

RESUMO

Coconut oil has properties that are beneficial to human health. It assists in reducing total cholesterol, triacylglycerol (TAG), phospholipids, low-density lipoprotein (LDL) cholesterol, and very low-density lipoprotein (VLDL) cholesterol in serum and tissues. So its production, and consequently consumption, have increased in recent years. However, it has been a target for intentional adulteration with lower priced oils and fats, such as soybean oil and palm kernel oil (PKO). Coconut oil (CO) and PKO have similar chemical and physical characteristics that make it difficult to verify adulteration of CO with PKO. This study demonstrates a simple, sensitive, and fast technique that uses direct infusion electrospray ionisation mass spectrometry (ESI-MS) in conjunction with principal component analysis (PCA), in order to detect CO adulterated with PKO. Among the seven commercial coconut oil samples analysed, three were adulterated with PKO. Therefore, the suggested direct infusion ESI-MS method can be used in routine analysis to guarantee the quality of coconut oil.


Assuntos
Óleo de Coco/química , Óleos de Plantas/análise , Óleo de Coco/análise , Óleo de Palmeira , Espectrometria de Massas por Ionização por Electrospray
6.
Curr Opin Clin Nutr Metab Care ; 21(2): 97-103, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29256925

RESUMO

PURPOSE OF REVIEW: Intravenous lipid emulsions (IVLEs) are an essential component of parenteral nutrition. With the recent incorporation of new lipid emulsions into the Canadian and American market, the clinician responsible for prescribing these lipids should be educated regarding the different fatty acid (FA) profiles of these lipids, as well as their metabolic and functional effects. RECENT FINDINGS: New IVLEs contain a mix of soybean oil and olive oil, or a mix of soybean oil, coconut oil, olive oil and fish oil. These new lipid emulsions provide less essential fatty acids (FAs) (linoleic and alpha linolenic acids) than in pure soybean oil, yet incorporation of fish oil into an IVLE may decrease the amount of essential FAs required. Fish oil is a treatment for hypertriglyceridemia, and therefore, IVLEs that include fish oil may decrease serum triglycerides. Historical perspective is that fish oil can be associated with increased bleeding time. Evidence suggests that there is no association between fish oil and increased bleeding in patients, even those who are using anticoagulants. New IVLEs provide less vitamin K than soybean oil alone. Patients, or the parenteral nutrition solutions that include these new IVLEs should be supplemented with vitamin K. SUMMARY: Canadian and American Guidelines for IVLEs were based on soybean oil. Current practice should be tailored to which IVLE is being prescribed.


Assuntos
Emulsões Gordurosas Intravenosas/química , Óleos de Peixe/análise , Nutrição Parenteral , Coagulação Sanguínea/efeitos dos fármacos , Canadá , Óleo de Coco/análise , Emulsões Gordurosas Intravenosas/efeitos adversos , Emulsões Gordurosas Intravenosas/farmacologia , Humanos , Hipertrigliceridemia/sangue , Hipertrigliceridemia/terapia , Ácido Linoleico/análise , Azeite de Oliva/análise , Óleo de Soja/análise , Estados Unidos , Vitamina K/análise , Ácido alfa-Linolênico/análise
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