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1.
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
2.
MethodsX ; 10: 101972, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36593759

RESUMO

During the course of the EU H2020 OLEUM project, a harmonized method was developed to quantify volatile markers of the aroma of virgin olive oil with the aim to support the work of sensory panel test to assess the quality grade. A peer validation of this method has been carried out, with good results in terms of analytical quality parameters. The method allows the quantification of volatile compounds by SPME-GC with two possible detectors, flame ionization detector and mass spectrometry, depending on the technical facilities of the labs applying this method. The method was optimized for the quantification of 18 volatile compounds that were selected as being markers responsible for positive attributes (e.g. fruity) and sensory defects (e.g. rancid and winey-vinegary). The quantification is carried out with calibration curves corrected by the internal standards. Additionally, a protocol is provided to prepare the calibration samples. This procedure enhances reproducibility between labs since one of the main sources of errors is the application of different procedures in calibration.

3.
Artigo em Inglês | MEDLINE | ID: mdl-32693705

RESUMO

Processing Factors (PFs) reflect the concentration or dilution of pesticide residues resulting from food processing. PFs are key elements to demonstrate the compliance of processed foods with Maximum residue levels (MRLs) as set by Regulation 396/2005. While efforts have been made by the European Food Safety Authority (EFSA) and by national authorities to compile PFs from processing studies, such PFs are not available for all pesticides/processed product combinations. The EU vegetable oil and proteinmeal industry association (FEDIOL) has therefore developed a theoretical approach to approximate MRLs in crude vegetable oils and fats, based on the partition coefficient (log Pow) of the pesticides and on the oil content of the raw materials. To substantiate this approach, a pilot-scale processing study was initiated with rapeseeds spiked with selected pesticides and the experimental PFs for these pesticides determined. The aims of this study were (i) to study the reliability of pilot-scale conditions for PF determination and (ii) to assess the experimental PFs obtained in comparison to the theoretical PFs proposed by FEDIOL. This study demonstrated that production yields obtained for crude oil and meal in this processing study are similar to those in industrial processes even if differences were observed in the individual production steps (mechanical or solvent extraction steps). The experimental PFs obtained confirmed that the chosen fat-soluble pesticides did concentrate in the oil fraction. For metalaxyl-M having a log Pow lower than 3, a partitioning between the oil and the meal was observed, as expected. By comparing the experimental PFs and theoretical PFs, it can be concluded that the FEDIOL approach can be recommended as a suitable tool when PFs derived from specific processing studies are missing. Similar studies on pesticides with wider ranges of log Pow are required in order to complete our conclusions on default PFs for vegetable oils.


Assuntos
Contaminação de Alimentos/análise , Manipulação de Alimentos , Praguicidas/análise , Óleos de Plantas/química , Sementes/química
4.
Foods ; 9(3)2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32204346

RESUMO

A set of 334 commercial virgin olive oil (VOO) samples were evaluated by six sensory panels during the H2020 OLEUM project. Sensory data were elaborated with two main objectives: (i) to classify and characterize samples in order to use them for possible correlations with physical-chemical data and (ii) to monitor and improve the performance of panels. After revision of the IOC guidelines in 2018, this work represents the first published attempt to verify some of the recommended quality control tools to increase harmonization among panels. Specifically, a new "decision tree" scheme was developed, and some IOC quality control procedures were applied. The adoption of these tools allowed for reliable classification of 289 of 334 VOOs; for the remaining 45, misalignments between panels of first (on the category, 21 cases) or second type (on the main perceived defect, 24 cases) occurred. In these cases, a "formative reassessment" was necessary. At the end, 329 of 334 VOOs (98.5%) were classified, thus confirming the effectiveness of this approach to achieve a better proficiency. The panels showed good performance, but the need to adopt new reference materials that are stable and reproducible to improve the panel's skills and agreement also emerged.

5.
Mol Ther Methods Clin Dev ; 12: 157-174, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30705921

RESUMO

Adeno-associated viruses (AAVs) are among the most efficient vectors for liver gene therapy. Results obtained in the first hemophilia clinical trials demonstrated the long-term efficacy of this approach in humans, showing efficient targeting of hepatocytes with both self-complementary (sc) and single-stranded (ss) AAV vectors. However, to support clinical development of AAV-based gene therapies, efficient and scalable production processes are needed. In an effort to translate to the clinic an approach of AAV-mediated liver gene transfer to treat Crigler-Najjar (CN) syndrome, we developed an (ss)AAV8 vector carrying the human UDP-glucuronosyltransferase family 1-member A1 (hUGT1A1) transgene under the control of a liver-specific promoter. We compared our construct with similar (sc)AAV8 vectors expressing hUGT1A1, showing comparable potency in vitro and in vivo. Conversely, (ss)AAV8-hUGT1A1 vectors showed superior yields and product homogeneity compared with their (sc) counterpart. We then focused our efforts in the scale-up of a manufacturing process of the clinical product (ss)AAV8-hUGT1A1 based on the triple transfection of HEK293 cells grown in suspension. Large-scale production of this vector had characteristics identical to those of small-scale vectors produced in adherent cells. Preclinical studies in animal models of the disease and a good laboratory practice (GLP) toxicology-biodistribution study were also conducted using large-scale preparations of vectors. These studies demonstrated long-term safety and efficacy of gene transfer with (ss)AAV8-hUGT1A1 in relevant animal models of the disease, thus supporting the clinical translation of this gene therapy approach for the treatment of CN syndrome.

6.
Am J Clin Nutr ; 91(5): 1220-6, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20335546

RESUMO

BACKGROUND: The modern Western lifestyle is characterized by the consumption of high-heat-treated foods because of their characteristic taste and flavor. However, it has been shown that treating food at high temperatures can generate potentially harmful compounds that promote inflammation and cardiovascular disease in subjects with diabetes. OBJECTIVE: The aim of this study was to determine whether high-heat-treated foods also pose a risk for healthy subjects. DESIGN: A randomized, crossover, diet-controlled intervention trial with 62 volunteers was designed to compare the potential metabolic effects of 2 diets, one that was based on mild steam cooking and another that was based on high-temperature cooking. These 2 diets differed mainly in their contents of Maillard reaction products (MRPs). MRPs were assessed in the diet and in subjects' feces, blood, and urine samples, with N(epsilon)-carboxymethyllysine as an indicator of MRPs. Biological indicators of glucose and lipid metabolism as well as oxidative stress were analyzed in subjects after 1 mo on each diet. RESULTS: In comparison with the steamed diet, 1 mo of consuming the high-heat-treated diet induced significantly lower insulin sensitivity and plasma concentrations of long-chain n-3 (omega-3) fatty acids and vitamins C and E [-17% (P < 0.002), -13% (P < 0.0001), and -8% (P < 0.01), respectively]. However, concentrations of plasma cholesterol and triglycerides increased [+5% (P < 0.01) and +9% (P < 0.01), respectively]. CONCLUSIONS: A diet that is based on high-heat-treated foods increases markers associated with an enhanced risk of type 2 diabetes and cardiovascular diseases in healthy people. Replacing high-heat-treatment techniques by mild cooking techniques may help to positively modulate biomarkers associated with an increased risk of diabetes mellitus and cardiovascular diseases.


Assuntos
Doenças Cardiovasculares/epidemiologia , Culinária , Diabetes Mellitus Tipo 2/epidemiologia , Temperatura Alta/efeitos adversos , Ácido Ascórbico/sangue , Índice de Massa Corporal , Doenças Cardiovasculares/etiologia , Colesterol/sangue , Estudos Cross-Over , Diabetes Mellitus Tipo 2/etiologia , Ácidos Graxos Ômega-3/sangue , Feminino , Humanos , Inflamação/etiologia , Insulina/fisiologia , Estilo de Vida , Reação de Maillard , Masculino , Fatores de Risco , Triglicerídeos/sangue , Vitamina E/sangue , Adulto Jovem
7.
J Agric Food Chem ; 56(15): 6241-5, 2008 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-18616270

RESUMO

A new sensitive and selective method has been developed for the quantification of the total coenzyme Q9 (CoQ9) and coenzyme Q10 (CoQ10) concentration in vegetable oil samples. The coenzyme Q fraction is isolated by solid-phase extraction (SPE) on amino phase eluting with a mixture of heptane:ethyl ether. The organic solvent is evaporated under nitrogen, and the residue is dissolved in a mixture of acetonitrile:tetrahydrofuran and finally is analyzed by reverse-phase high-performance liquid chromatography with a mass detector. The sensitivity of the method is based on the high efficient formation of the radical anions [M (-.)] of CoQ9 and CoQ10 by negative atmospheric pressure ionization. Interferences are minimized by using mass detection of the [M (-.)] ions ( m/ z = 797.5 for CoQ9 and m/ z = 862.5 for CoQ10) in selective reaction monitoring mode ( m/ z = 797.5 --> m/ z = 779.5 and m/ z = 862.5 --> m/ z = 847.5) using a triple-quadrupole mass spectrometer. The method was successfully applied to sunflower, soybean, and rapeseed oils, with a limit of quantification of 0.025 mg/kg for both compounds.


Assuntos
Óleos de Plantas/química , Ubiquinona/análogos & derivados , Cromatografia Líquida de Alta Pressão , Ácidos Graxos Monoinsaturados , Óleo de Brassica napus , Sensibilidade e Especificidade , Solventes , Óleo de Soja/química , Óleo de Girassol , Ubiquinona/análise
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