No description available.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Ocimum. micranthum Willd. à uma planta popularmente conhecida como alfavaca de folha miÃda ou estoraque sendo utilizada na medicina popular no tratamento de gripe, resfriados, febre, tosse, bronquites, nas infecÃÃes intestinais e estomacais, nas otites e como estimulante e carminativa. O presente estudo teve como objetivo mostrar a atividade do Ãleo essencial de Ocimum micranthum e seu principal constituinte, o cinamato de metila, em traquÃias isoladas de ratos Wistar. Foi evidenciado que tanto o OEOM quanto o cinamato de metila, nas concentraÃÃes de 1-1000 Âg/mL, nÃo interferem no tÃnus basal, no entanto sÃo capazes de reverter a resposta contrÃtil induzida por cloreto de potÃssio e carbacol com CI50 de 112 e 128,2 Âg/mL (para o OEOM) e 308 e 100 Âg/mL (para o cinamato de metila) respectivamente. . A concentraÃÃo de 100 Âg/mL OEOM, quando adicionada antes do agente contrÃtil, à capaz de atenuar a resposta mÃxima do KCl em traquÃias de ratos naÃve, fato que nÃo ocorreu quando a contraÃÃo foi induzida por carbacol na presenÃa de nitrendipina. Adicionalmente, em animais submetidos a modelos de asma pela OVA, o OEOM se mostrou mais ativo em animais desafiados do que apenas sensibilizados. Portanto, o mecanismo envolvido nos efeitos miorrelaxante e antiespasmÃdico do OEOM Ã, pelo menos em parte, devido à sua aÃÃo preferencial nos canais de cÃlcio operados por voltagem (VOCC). Seu principal constituinte, o cinamato de metila, parece estar envolvido nos efeitos miorrelaxantes do OEOM. / The Ocimum. micranthum Willd. is a plant popularly known as âalfavaca-de-folha-miÃdaâ or âestoraqueâ and is used in folk medicine to treat flu, colds, fever, cough, bronchitis, stomach and intestinal infections, ear infections and as stimulant and carminative. This study aimed to show the activity of its essential oil (EOOM) and of its main constituent, methyl cinnamate, in rat isolated trachea. It was shown that both the OEOM and methyl cinnamate (1-1000 Âg/mL) did not change the basal tone, but they were able to reverse the contractile response induced by potassium chloride or carbachol with IC50 of 112 and 128.2 Âg/mL (for EOOM) and 308 and 100 μg/mL (for methyl cinnamate), respectively. At 100 Âg/mL, added before the contractile agent, EOOM attenuated maximal response to KCl in trachea from naÃve rats. This effect did not occur when contraction was induced by carbachol in the presence of nitrendipine. Additionally, in animals subjected to an ovalbumin-sensitized model of asthma, EOOM was more active in challenged than in sensitized animals. In conclusion,th e myorelaxant and antispasmodic effects of the EOOM are due to its preferential action on voltage-operated calcium channels. Its major constituent, methyl cinnamte, appears to be involved in the pharmacological effects of the EOOM.

L'objectif de ce travail était d'étudier l'impact du mode de préparation et de la formulation de bioplastiques transparents issus d'huile de soja sur leur structure et leurs propriétés thermiques et mécaniques. Nous nous sommes plus particulièrement intéressés à l'huile de soja époxydée (ESO), qui a ensuite été acrylée et co-polymérisée avec méthacrylate de méthyle (MMA) en présence ou non de nano-particules de dioxyde de titane. Deux méthodes de préparation d'ESO ont été comparées. La première a fait appel à une époxydation chimique en présence de peroxyde d'hydrogène et d'acide formique. L'acide sulfurique a été utilisé comme catalyseur pour la production de peracides, ces oxydants forts générant ensuite des époxydes par attaque des doubles liaisons des acides gras de l'huile. La seconde consistait en une époxydation chimio-enzymatique, les peracides étant alors générés dans des conditions douces de pH et de température par catalyse enzymatique en présence d'H2O2 et d'huile. Deux types de lipases ont été utilisées comme biocatalyseurs : la lipase de Candida antarctica (Novozyme 435) et la lipase/acyltransférase de C. parapsilosis. Un contrôle de la réaction a permis d'obtenir des produits à différents degrés d'époxydation (50 et 75  3 %). Les effets du mode d'époxydation, du degré d'acrylation et des teneurs en MMA et TiO2 sur les propriétés des bioplastiques obtenus ont été étudiés par FTIR, RMN 1D et 2D, DMTA, TGA et par mesure des propriétés mécaniques.Mots-clés : Biocomposite, Bioplatique, Nanocomposite, Huile de soja époxydée et acrylée (AESO), Dioxyde de titane (TiO2), Biocatalyse, Lipase / The aim of this research to study the effect the production method and the formulation of transparent soybean oil-based bioplastics on their structure and their thermal and mechanical properties. We focused on epoxidized soybean oil (ESO), that was acrylated and copolymerized methyl methacrylate (MMA) with and without titanium dioxide (TiO2). Two methods of ESO preparation were compared. The first used chemical epoxidation in the presence of H2O2 and formic acid, using sulfuric acid as a catalyst to produce peracids as strong oxydants for the epoxidation. The second one was a chemo-enzymatic method where the peracids were generated in mild conditions by an enzyme in the presence of H2O2. Two types of lipases were selected as biocatalysts for the chemo-enzymatic epoxidation: Novozyme®435 and a non-commercial lipase/acyltransferase (CpLIP2). The reaction was controlled so as to obtain different degrees of epoxidation (DOE), i.e. 50+/-3 mol% and 75+/-3 mol%, from both methods. Acrylated ESO (AESO) was chemically synthesized by acrylation of ESO and acrylic acid. Then AESO was copolymerized with MMA and cured to form a rigid polymer using 1 wt% of benzoyl peroxide as a free radical initiator. A nanocomposite was prepared by blending AESO-co-PMMA with 0.1-0.2 wt% nano-TiO2 (particle size 2-5 nm). The effect of degree of acrylation, MMA content and titanium dioxide content on structural, tensile and thermal properties of the obtained bioplastics were studied using Fourier transform infrared spectrometer (FTIR), 1D and 2D NMR, dynamic mechanical thermal analysis (DMTA), thermogravimetric analysis (TGA) and mechanical properties determination.

Song Jing-mei. / Thesis submitted in: December 1998. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 141-156). / Abstract also in Chinese. / Title page --- p.i / Acknowledgments --- p.ii / Table of contents --- p.iii / Abbreviations --- p.viii / Abstract --- p.x / 摘要 --- p.xii / Chapter Chapter1 --- Introduction --- p.1 / Chapter Chapter2 --- Evaluation of Antiulcer Effect Exhibited by Hippophae rhamnoides Using Different Ulcer Models / Chapter 2.1 --- Introduction --- p.20 / Chapter 2.1.1 --- Ethanol-induced gastric lesions --- p.24 / Chapter 2.1.2 --- NSAID-induced gastric lesions --- p.24 / Chapter 2.1.3 --- Stress-induced gastric lesions --- p.25 / Chapter 2.1.4 --- Pylorus ligation-induced gastric lesions --- p.25 / Chapter 2.1.5 --- Acetic acid-induced chronic gastric ulcer --- p.26 / Chapter 2.1.6 --- Necrotizing agent-induced lesion model --- p.27 / Chapter 2.2 --- Materials and Methods / Chapter 2.2.1 --- Plant materials --- p.28 / Chapter 2.2.2 --- Identification of the plant --- p.28 / Chapter 2.2.3 --- Preparation of crude extract for animal studies --- p.28 / Chapter 2.2.4 --- Experimental animals --- p.31 / Chapter 2.2.5 --- Ethanol-induced gastric mucosal lesions --- p.31 / Chapter 2.2.6 --- Acidified aspirin-induced gastric lesions --- p.32 / Chapter 2.2.7 --- Water immersion plus restraint-induced stress lesion model --- p.32 / Chapter 2.2.8 --- Pylorus ligation-induced gastric lesions --- p.32 / Chapter 2.2.9 --- Acetic acid-induced chronic gastric ulcer --- p.34 / Chapter 2.2.10 --- Necrotizing agent-induced gastric lesions --- p.34 / Chapter 2.2.11 --- Test of acute toxicity of Hippophae --- p.35 / Chapter 2.2.12 --- Statistical analysis --- p.35 / Chapter 2.3 --- Results / Chapter 2.3.1 --- Effect of Hr extract on ethanol-induced gastric lesions --- p.36 / Chapter 2.3.2 --- Effect of Hr extract on aspirin-induced gastric damage --- p.39 / Chapter 2.3.3 --- Effect of Hr extract on stress-induced gastric lesions --- p.40 / Chapter 2.3.4 --- Effect of Hr extract on pylorus ligation-induced gastric injury --- p.43 / Chapter 2.3.5 --- Effect of Hr extract on acetic acid-induced chronic ulcer --- p.48 / Chapter 2.3.6 --- Effect of Hr extract on necrotizing agent-induced gastric damage --- p.54 / Chapter 2.3.7 --- Test of acute toxicity of Hr --- p.55 / Chapter 2.4 --- Discussion / Chapter 2.4.1 --- Cytoprotective effect of Hr against ethanol-induced lesions --- p.56 / Chapter 2.4.2 --- Preventive effect of Hr on NSAIDs-induced gastric lesions --- p.57 / Chapter 2.4.3 --- Inhibitory effect of Hr on stress-induced lesions --- p.58 / Chapter 2.4.4 --- Inhibitory effect of Hr extract on pylorus ligation-induced gastric lesions --- p.59 / Chapter 2.4.5 --- Healing effect of Hr extract on acetic acid-induced gastric ulcer --- p.60 / Chapter 2.4.6 --- Protective effect of Hr extract on necrotizing agent-induced gastric damage --- p.61 / Chapter 2.4.7 --- Summary --- p.61 / Chapter Chapter3 --- Study on Cytoprotective Effect of Hippophae rhamnoides on Ethanol-induced Gastric Damage / Chapter 3.1 --- Introduction --- p.63 / Chapter 3.2 --- Materials and Methods --- p.65 / Chapter 3.2.1 --- Chemicals and Instruments --- p.65 / Chapter 3.2.2 --- Test on effect of different concentrations of ethanol on gastric mucosa --- p.67 / Chapter 3.2.3 --- Examination of the gastric protective effect of Hr extract by different routes of administration --- p.68 / Chapter 3.2.4 --- Study on relationship between gastric protective effect of Hr extract and endogenous PGs --- p.68 / Chapter 3.2.5 --- Measurement of gastric mucosal blood flow (GMBF) --- p.69 / Chapter 3.2.6 --- Measurement of gastric secretion and acidity in gastric juice --- p.70 / Chapter 3.2.7 --- Measurement of gastric gastric emptying rate --- p.70 / Chapter 3.2.8 --- Measurement of pepsin content in gastric juice --- p.71 / Chapter 3.2.9 --- Measurement of protein content in gastric juice --- p.73 / Chapter 3.2.10 --- Measurement of mucus content on gastric wall --- p.75 / Chapter 3.2.11 --- Measurement of GSH content in gastric mucosa --- p.77 / Chapter 3.2.12 --- Measurement of PGE2 content in gastric mucosa --- p.79 / Chapter 3.2.13 --- Determination of protein content in gastric mucosa --- p.81 / Chapter 3.3 --- Results / Chapter 3.3.1 --- Test on gastric lesions induced by different concentrations of ethanol --- p.83 / Chapter 3.3.2 --- Effect of Hr extract on ethanol-induced gastric damage by different routes of administration --- p.83 / Chapter 3.3.3 --- Effect of Hr extract on GMBF and output of gastric acid --- p.85 / Chapter 3.3.4 --- Effect of Hr extract on gastric emptying rate --- p.87 / Chapter 3.3.5 --- Effect of Hr extract on gastric mucus --- p.88 / Chapter 3.3.6 --- Effect of Hr extract on gastric GSH content --- p.89 / Chapter 3.3.7 --- Influence of Hr extract on endogenous prostanglandin-E2 --- p.90 / Chapter 3.3.8 --- Antagonistic effect of indomethacin on the gastric protection of Hr extract --- p.91 / Chapter 3.4 --- Discussion / Chapter 3.4.1 --- Formation of gastric lesions induced by ethanol at different concentrations --- p.92 / Chapter 3.4.2 --- Different routes of administration --- p.92 / Chapter 3.4.3 --- "Role of GMBF, gastric acidity and acid output in the formation of gastric lesions" --- p.93 / Chapter 3.4.4 --- Effect of Hr extract on gastric motility --- p.95 / Chapter 3.4.5 --- Effect of Hr extract on gastric mucus --- p.96 / Chapter 3.4.6 --- Effect of Hr extract on gastric GSH content --- p.96 / Chapter 3.4.7 --- Effect of Hr extract on endogenous prostaglandins --- p.98 / Chapter 3.4.8 --- Summary --- p.99 / Chapter Chapter 4 --- Study on plant constituents of Hippophae rhamnoides / Chapter 4.1 --- Introduction --- p.100 / Chapter 4.2 --- Materials and Methods --- p.100 / Chapter 4.2.1 --- Plant Materials --- p.100 / Chapter 4.2.2 --- Plant Extraction --- p.101 / Chapter 4.2.3 --- Fractionation of hexane-extract by column chromatography --- p.103 / Chapter 4.2.4 --- Phytochemical identification and analyses of vitamin content in Hr extract --- p.104 / Chapter 4.2.4.1 --- Identification of vitamin A and vitamin C in the Hr extract by TLC --- p.104 / Chapter 4.2.4.2 --- Identification of α-tocopherol and γ-tocopherol by HPLC --- p.105 / Chapter 4.2.4.3 --- Analyses of the content of α-tocopherol in the Hr extract --- p.108 / Chapter 4.2.4.4 --- Identification and analysis of fatty acid in the Hr fractions --- p.111 / Chapter 4.2.4.4.1 --- Esterification of fatty acids --- p.111 / Chapter 4.2.4.4.2 --- Isolation and identification of FAME by GC-MS --- p.111 / Chapter 4.2.4.5 --- Quantitative analysis of composition and relative content of fatty acid in the Hr fractions --- p.112 / Chapter 4.3 --- Results / Chapter 4.3.1 --- Phytochemical analysis and identification --- p.114 / Chapter 4.3.1.1 --- Identification of vitamin A --- p.114 / Chapter 4.3.1.2 --- Identification of vitamin C --- p.115 / Chapter 4.3.1.3 --- Identification of α-tocopherol and γ-tocopherol --- p.116 / Chapter 4.3.1.4 --- Quantitative analysis of α-tocopherol content in the Hr extract --- p.117 / Chapter 4.3.1.5 --- Identification of fatty acid composition --- p.117 / Chapter 4.3.1.6 --- Analysis of relative content of fatty acids in the Hr extract --- p.122 / Chapter 4.3.1.7 --- Study on phytosterols of Hr --- p.124 / Chapter 4.3.2 --- Examination of antiulcer effect of Hr fractions against ethanol-induced gastric lesions --- p.124 / Chapter 4.3.2.1 --- Effect of different extracts of Hr seed on ethanol-induced gastric lesions --- p.125 / Chapter 4.3.2.2 --- Effect of fractions of hexane-extract of Hr on gastric lesions induced by ethanol --- p.126 / Chapter 4.3.2.3 --- Effect of Hr components on gastric lesions induced by different ulcer models --- p.127 / Chapter 4.3.2.3.1 --- Effect of Hr components on ethanol-induced lesions --- p.127 / Chapter 4.3.2.3.2 --- Effect of Hr components against stress-induced gastric lesions --- p.128 / Chapter 4.3.2.3.3 --- Effect of β-sitosterol against gastric lesions induced by pylorus ligation --- p.129 / Chapter 4.4 --- Discussion / Chapter 4.4.1 --- Role of fatty acids in the stomach protection --- p.130 / Chapter 4.4.2 --- Role of vitamins in the gastric protection --- p.133 / Chapter 4.4.3 --- Role of plant terpenoids in the stomach --- p.134 / Chapter 4.4.4 --- Summary --- p.135 / Chapter Chapter 5 --- General discussion --- p.136 / References --- p.141

A novel analytical method is developed to examine the chemical composition of plant oils by electrospray ionisation high-resolution Fourier transform ion cyclotron resonance mass spectrometry in both positive- and negative-ion modes. To date, this is the first reported application of this technique for the study of macadamia nut oil. Samples of macadamia nut oil from the Macadamia Integrifolia- Proteaceae family (smooth shell) are examined. The fatty acid profile of the oil is obtained by this mass spectrometric examination of the transesterified and hydrolysed oil samples. The Fourier transform ion-cyclotron resonance mass spectrometry results are compared to those obtained from similar samples using gas chromatography-mass spectrometry techniques. High performance liquid chromatography and Fourier transform ion cyclotron resonance mass spectrometry are used to separate and assign the isomers present in the methanol extract of the oils in separate experiments. Significant results in this study include: - The first observation and identity of a number of oxidised triacylglycerols in macadamia oil samples. - The first observation of oxidised and free fatty acids, measured directly in hydrolysed oil and in the methanol extract of macadamia oil. - High resolution Fourier transform ion cyclotron resonance mass spectrometry in broadband mode which enables isobars to be observed. - Esterified oil Fourier transform ion cyclotron resonance mass spectrometry results are consistent with our gas chromatography-mass spectrometry results and with the results of similar studies on macadamia oil in the literature. - A number of fatty acids with odd number of carbon atoms are observed in the oil. - In electrospray ionisation Fourier transform ion cyclotron resonance mass spectrometry of oils, the sample preparation is straightforward. The sample is dissolved in methanol or acetonitrile and the solution is introduced to the electrospray source directly. Introducing oil samples to the gas chromatograph-mass spectrometer needs the oils to be esterified prior to the analysis. - In this work, state-of-the-art mass spectrometry demonstrates distinct advantages in comparison to gas chromatography measurements such as direct identification of free fatty acids in oil samples, whereas this is not possible in gas chromatography-mass spectrometry due to the required esterification step prior to the analysis. - High performance liquid chromatography fraction collection is combined with Fourier transform ion cyclotron resonance mass spectrometry in off-line mode and found to improve the sensitivity, selectivity and signal to noise levels due to the lower number of compounds in each high performance liquid chromatography fraction compared to the methanol extract of macadamia oil sample. Also isomers of monoacylglycerols have been resolved using the high performance liquid chromatography technique.

A novel analytical method is developed to examine the chemical composition of plant oils by electrospray ionisation high-resolution Fourier transform ion cyclotron resonance mass spectrometry in both positive- and negative-ion modes. To date, this is the first reported application of this technique for the study of macadamia nut oil. Samples of macadamia nut oil from the Macadamia Integrifolia- Proteaceae family (smooth shell) are examined. The fatty acid profile of the oil is obtained by this mass spectrometric examination of the transesterified and hydrolysed oil samples. The Fourier transform ion-cyclotron resonance mass spectrometry results are compared to those obtained from similar samples using gas chromatography-mass spectrometry techniques. High performance liquid chromatography and Fourier transform ion cyclotron resonance mass spectrometry are used to separate and assign the isomers present in the methanol extract of the oils in separate experiments. Significant results in this study include: - The first observation and identity of a number of oxidised triacylglycerols in macadamia oil samples. - The first observation of oxidised and free fatty acids, measured directly in hydrolysed oil and in the methanol extract of macadamia oil. - High resolution Fourier transform ion cyclotron resonance mass spectrometry in broadband mode which enables isobars to be observed. - Esterified oil Fourier transform ion cyclotron resonance mass spectrometry results are consistent with our gas chromatography-mass spectrometry results and with the results of similar studies on macadamia oil in the literature. - A number of fatty acids with odd number of carbon atoms are observed in the oil. - In electrospray ionisation Fourier transform ion cyclotron resonance mass spectrometry of oils, the sample preparation is straightforward. The sample is dissolved in methanol or acetonitrile and the solution is introduced to the electrospray source directly. Introducing oil samples to the gas chromatograph-mass spectrometer needs the oils to be esterified prior to the analysis. - In this work, state-of-the-art mass spectrometry demonstrates distinct advantages in comparison to gas chromatography measurements such as direct identification of free fatty acids in oil samples, whereas this is not possible in gas chromatography-mass spectrometry due to the required esterification step prior to the analysis. - High performance liquid chromatography fraction collection is combined with Fourier transform ion cyclotron resonance mass spectrometry in off-line mode and found to improve the sensitivity, selectivity and signal to noise levels due to the lower number of compounds in each high performance liquid chromatography fraction compared to the methanol extract of macadamia oil sample. Also isomers of monoacylglycerols have been resolved using the high performance liquid chromatography technique.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2007. / Härtill 4 uppsatser.

La nutrition constitue l'un des facteurs déterminants du développement ou de la prévention de diverses pathologies. Parmi les trois classes de nutriments majeurs, les lipides alimentaires occupent une place essentielle dans cette relation nutrition-santé puisque leur déséquilibre qualitatif est impliqué dans l'incidence des maladies cardiovasculaires. L'importance de l'équilibre alimentaire justifie le développement de produits fonctionnels au profil nutritionnel amélioré. En parallèle, suite à la prise de conscience de l'impact environnemental de la production alimentaire, il est aujourd'hui important d'inscrire le choix des matières premières et des procédés dans une démarche de développement durable.Dans ce contexte, les travaux menés durant cette thèse concernent tout d'abord l'amélioration des propriétés nutritionnelles d'une matière grasse végétale tartinable par réduction de sa teneur en acides gras (AG) saturés délétères, mais également la limitation de son impact environnemental par réduction des ingrédients issus de la filière palme. La mise au point d'un procédé d'interestérification enzymatique vise à ajuster les propriétés rhéologiques du produit sans modifier le profil global en AG, et sans utiliser de solvants ou produits chimiques grâce à l'action d'un biocatalyseur (lipase). Ces travaux ont conduit au développement jusqu'au stade pilote d'un substitut interestérifié par voie enzymatique permettant de réduire la teneur en AG saturés délétères de 65% et l'utilisation de dérivés d'huile de palme de 70% tout en maintenant une fonctionnalité similaire au produit actuel. En parallèle, un procédé enzymatique à également été exploité dans l'étude d'une nouvelle méthode d'analyse de la régiodistribution : l'évaluation des sélectivités de la lipase de Rhizopus oryzae a montré son potentiel pour l'analyse de la position sn-2 des triacylglycérols contenant des AG à chaines moyennes. / Nutrition is one of the main factors contributing to various diseases occurrence or prevention. Among the three major types of nutrients, dietary lipids are essential in this nutrition-health relationship since lipid disorder is associated with an increased risk of cardiovascular diseases. Thus, the importance of a healthy diet explains the development of functional foods with improved nutritional properties. Furthermore, with environmental impact of food production being a growing concern for consumers, selection of raw materials and processes should meet the requirements for sustainable development. In this context, this work concerns the improvement of the nutritional properties of a vegetable oil spread by reducing its unhealthy fatty acids (FA) content, but also the limitation of its environmental impact by minimizing the use of palm oil products. An enzymatic interesterification process has been developed to adapt rheological properties without modifying FA profile nor using solvents and chemical products by action of a biocatalyst (lipase). This work led to the pilot-scale development of an enzymatically interesterified substitute allowing to reduce the unhealthy FA content by 65%, and the use of palm oil products by 70% while keeping a functionality similar to the current product.At the same time, an enzymatic approach has also been used in the investigation of a new method for regiodistribution analysis. Thus, Rhizopus oryzae lipase appeared to be a good candidate for the sn-2 position analysis of triacylglycerols containing medium chain fatty acids.

O crescente mercado dos produtos naturais, fomentado pelo interesse dos consumidores por alimentos que auxiliem a promoção da saúde, tem pressionado a indústria alimentícia na oferta por novos alimentos. Dentre estes alimentos, encontram-se os óleos vegetais extraídos a frio, reconhecidos por preservarem compostos bioativos característicos e, alguns deles, serem fontes de ácidos graxos (AG) essenciais. A categoria dos óleos e gorduras apresenta, dentre outros alimentos, uma importante fonte de exposição aos hidrocarbonetos policíclicos aromáticos (HPAs), um grupo de contaminantes químicos orgânicos, alguns com ação carcinogênica. Este trabalho teve como objetivo avaliar os óleos vegetais extraídos a frio quanto aos parâmetros de identidade, de qualidade e à ocorrência de HPAs. Foram avaliadas 40 amostras, dez de cada tipo (coco, cártamo, prímula e linhaça), de diferentes marcas, adquiridas no comércio da cidade de São Paulo. Foram realizados os ensaios de perfil de AG, índice de acidez, índice de peróxido, p-anisidina, valor total de oxidação (totox) e HPAs (benzo(a)antraceno, criseno, benzo(b)fluoranteno e benzo(a)pireno). Quanto aos AG, catorze óleos (35 por cento ) não apresentaram perfis de ácidos graxos característicos que os declarados em seus rótulos, incluindo um de coco, quatro de cártamo e nove de prímula. Os valores para acidez estavam inadequados em relação a legislação para três óleos de linhaça (7,5 por cento ). Para o peróxido, quatro óleos (10 por cento ) estavam acima do limite da legislação, sendo dois de linhaça e dois de prímula. Os valores de p-anisidina variaram de <LQ a 12,98, sendo o menor valor encontrado nas amostras de coco e o maior em uma de prímula, que apresentava um odor alterado. No ensaio de totox, 37,5% das amostras apresentaram valores acima da recomendação da literatura, especialmente os óleos de cártamo e prímula. Já para os HPAs, pelo menos um dos hidrocarbonetos analisados foi detectado em 97,5% das amostras avaliadas; três amostras de prímula (7,5%) apresentaram níveis acima do permitido pela Comunidade Européia para BaP e, para a soma dos 4 HPAs, oito óleos (20%) estavam em desacordo: dois de cártamo, quatro de prímula e dois de linhaça. Este trabalho expõe os problemas relacionados aos parâmetros de identidade, qualidade e contaminação dos óleos vegetais comercializados como extraídos a frio e reforçam a importância de um contínuo monitoramento destes produtos. / The natural product market growth, stimulated by the interest of consumers in foods that support health promotion, has encouraged the food industry to supply new kinds of foods. Among these are the cold-pressed vegetable oils, recognized by preserving characteristic bioactive compounds and, some of them, are sources of essential fatty acids (FA). The category of oils and fats owns, within others foods, an important source of exposure to polycyclic aromatic hydrocarbons (PAHs), a group of organic chemical contaminants, some of them with carcinogenic activity. This study aimed at evaluating cold-pressed vegetable oils in relation to the PAHs occurrence, as well as the quality and identity parameters. Forty samples being ten of each type (coconut oil, safflower oil, evening primrose oil and flaxseed oil) of distinct brands, which were acquired in different markets from São Paulo, were evaluated. Fatty acids profile, acid value, peroxide value, p-anisidine value, total oxidation value (totox) and PAHs (benzo(a)anthracene, chrysene, benzo(b)fluoranthene and benzo(a)pyrene) were analyzed. As for FA, fourteen oils (35 per cent ) showed different fatty acids profiles according to the ones on their labels, including one of coconut oil, four of safflower oils and nine of evening primrose oils. The acid values were unsuitable towards the legislation to three flaxseed oils (7.5 per cent ). As for peroxide values, four of the oils (10 per cent ) were above the legislation limit, including two of flaxseed oils and two of evening primrose ones. The p-anisidine values ranged from <LOQ to 12.98, being the smallest value found in the coconut oils samples and the biggest ones in an evening primrose oil, which featured an altered odor. In the totox analysis, 37,5% of the samples presented values above the normal pattern according to literature, mailly the safflower and theevening primrose oils. Regarding the PAHs, at least one of the analyzed hydrocarbons was detected in 97,5% of the samples; three of the primrose samples (7,5%) had levels above those allowed by the European Community for BaP. According to the sum of 4 PAHs, eight oils (20%) were in disagreement: two of safflower oils, four of evening primrose oils and two of flaxseed oils. This study exposes problems related to identity and quality parameters, contamination of vegetable oils marketed as cold-pressed. It also aims at reinforcing the importance of a continuous monitoring os these products.

O crescente mercado dos produtos naturais, fomentado pelo interesse dos consumidores por alimentos que auxiliem a promoção da saúde, tem pressionado a indústria alimentícia na oferta por novos alimentos. Dentre estes alimentos, encontram-se os óleos vegetais extraídos a frio, reconhecidos por preservarem compostos bioativos característicos e, alguns deles, serem fontes de ácidos graxos (AG) essenciais. A categoria dos óleos e gorduras apresenta, dentre outros alimentos, uma importante fonte de exposição aos hidrocarbonetos policíclicos aromáticos (HPAs), um grupo de contaminantes químicos orgânicos, alguns com ação carcinogênica. Este trabalho teve como objetivo avaliar os óleos vegetais extraídos a frio quanto aos parâmetros de identidade, de qualidade e à ocorrência de HPAs. Foram avaliadas 40 amostras, dez de cada tipo (coco, cártamo, prímula e linhaça), de diferentes marcas, adquiridas no comércio da cidade de São Paulo. Foram realizados os ensaios de perfil de AG, índice de acidez, índice de peróxido, p-anisidina, valor total de oxidação (totox) e HPAs (benzo(a)antraceno, criseno, benzo(b)fluoranteno e benzo(a)pireno). Quanto aos AG, catorze óleos (35 por cento ) não apresentaram perfis de ácidos graxos característicos que os declarados em seus rótulos, incluindo um de coco, quatro de cártamo e nove de prímula. Os valores para acidez estavam inadequados em relação a legislação para três óleos de linhaça (7,5 por cento ). Para o peróxido, quatro óleos (10 por cento ) estavam acima do limite da legislação, sendo dois de linhaça e dois de prímula. Os valores de p-anisidina variaram de <LQ a 12,98, sendo o menor valor encontrado nas amostras de coco e o maior em uma de prímula, que apresentava um odor alterado. No ensaio de totox, 37,5% das amostras apresentaram valores acima da recomendação da literatura, especialmente os óleos de cártamo e prímula. Já para os HPAs, pelo menos um dos hidrocarbonetos analisados foi detectado em 97,5% das amostras avaliadas; três amostras de prímula (7,5%) apresentaram níveis acima do permitido pela Comunidade Européia para BaP e, para a soma dos 4 HPAs, oito óleos (20%) estavam em desacordo: dois de cártamo, quatro de prímula e dois de linhaça. Este trabalho expõe os problemas relacionados aos parâmetros de identidade, qualidade e contaminação dos óleos vegetais comercializados como extraídos a frio e reforçam a importância de um contínuo monitoramento destes produtos. / The natural product market growth, stimulated by the interest of consumers in foods that support health promotion, has encouraged the food industry to supply new kinds of foods. Among these are the cold-pressed vegetable oils, recognized by preserving characteristic bioactive compounds and, some of them, are sources of essential fatty acids (FA). The category of oils and fats owns, within others foods, an important source of exposure to polycyclic aromatic hydrocarbons (PAHs), a group of organic chemical contaminants, some of them with carcinogenic activity. This study aimed at evaluating cold-pressed vegetable oils in relation to the PAHs occurrence, as well as the quality and identity parameters. Forty samples being ten of each type (coconut oil, safflower oil, evening primrose oil and flaxseed oil) of distinct brands, which were acquired in different markets from São Paulo, were evaluated. Fatty acids profile, acid value, peroxide value, p-anisidine value, total oxidation value (totox) and PAHs (benzo(a)anthracene, chrysene, benzo(b)fluoranthene and benzo(a)pyrene) were analyzed. As for FA, fourteen oils (35 per cent ) showed different fatty acids profiles according to the ones on their labels, including one of coconut oil, four of safflower oils and nine of evening primrose oils. The acid values were unsuitable towards the legislation to three flaxseed oils (7.5 per cent ). As for peroxide values, four of the oils (10 per cent ) were above the legislation limit, including two of flaxseed oils and two of evening primrose ones. The p-anisidine values ranged from <LOQ to 12.98, being the smallest value found in the coconut oils samples and the biggest ones in an evening primrose oil, which featured an altered odor. In the totox analysis, 37,5% of the samples presented values above the normal pattern according to literature, mailly the safflower and theevening primrose oils. Regarding the PAHs, at least one of the analyzed hydrocarbons was detected in 97,5% of the samples; three of the primrose samples (7,5%) had levels above those allowed by the European Community for BaP. According to the sum of 4 PAHs, eight oils (20%) were in disagreement: two of safflower oils, four of evening primrose oils and two of flaxseed oils. This study exposes problems related to identity and quality parameters, contamination of vegetable oils marketed as cold-pressed. It also aims at reinforcing the importance of a continuous monitoring os these products.