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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.
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
3.
Food Chem Toxicol ; 46(2): 787-96, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18060676

RESUMO

This study reports the effect of the fat-soluble vitamin A or vitamin E and grape seed proanthocyanidin extract (GSPE) on oxidative DNA damage estimated by 8-oxo-7, 8-dihydro-2'-deoxyguanosine (8-oxodG) contents in urine and leukocyte of rats. Little is known about the antioxidant potency of dietary anthocyanidins and consequently, the aim of this study was to establish whether anthocyanidins could act as putative antioxidant micronutrients. Seven groups of male Sprague-Dawley rats were fed during 47 days with the following diets: a basic diet, two deficient vitamin A or E diets, two supplemented vitamin A or E diets and two supplemented diets enriched with two doses of grape seed proanthocyanidin extract. At the end of the diet intervention period, 24h, urine and blood were collected. The levels of 8-oxodG in leukocytes rats were significantly lower in the supplemented vitamin A, E and GSPE diet groups with respect to the control group. However, consumption of alpha-tocopherol, vitamin A or GSPE had no effect on the excretion of the oxidised nucleoside 8-oxodG. These results suggest that a vitamin E and A and GSPE enriched-diets have a protective effect on oxidative DNA damage limited to rat leukocytes.


Assuntos
Antioxidantes/farmacologia , Dano ao DNA/efeitos dos fármacos , Desoxiguanosina/análogos & derivados , Leucócitos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Proantocianidinas/farmacologia , Vitamina A/farmacologia , Vitamina E/farmacologia , Vitaminas/farmacologia , 8-Hidroxi-2'-Desoxiguanosina , Animais , Desoxiguanosina/sangue , Desoxiguanosina/urina , Dieta , Extrato de Sementes de Uva , Leucócitos/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley
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