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This study investigated Passiflora edulis peel flour (PEPF) intake and its effect against high-fat diet-induced obesity. PEPF is a source of fiber and phenolic compounds, which can decrease oxidative stress and inflammatory cytokines, both linked to chronic inflammatory response and fat deposition in obesity. Therefore, we hypothesized that PEPF intake could decrease inflammatory cytokines and oxidative stress observed in obesity, leading to decrease of fatness and chronic inflammatory response. The aims of the study were to evaluate the lipid peroxidation, the expression of antioxidants enzymes, and inflammatory parameters in obese rats. Male Sprague-Dawley rats were divided into 3 groups (n = 8 per group) according to the diets: control (based on AIN-93G), high-fat (HF, 35% fat w/w), and HF with PEPF (HFPF), and the experiment lasted for 10 weeks. PEPF showed high dietary fiber content and bioactive compounds, such as ferulic acid, and β-carotene. PEPF intake was effective in reducing body weight gain (13.31%) and total body fat (22.58%). The lipid peroxidation in the liver and adipose tissue decreased in the HFPF group compared to HF-fed animals, whereas hepatic glutathione peroxidase and glutathione reductase activity and their expressions in the liver were higher in HFPF than HF. In addition, the PEPF intake decreased inflammatory cytokines in serum. These results suggest that PEPF intake decreases oxidative stress, possibly by the increase of antioxidant enzymes expression. Furthermore, PEPF decreases inflammatory response and protects from adiposity. Then, PEPF could act as an adjuvant to control of early parameters in obesity dysfunction.

The consumption of chia seeds products has increased recently and it has been suggested that the inclusion of this functional food in a daily human diet could contribute to improve consumers' health. However, a better knowledge about the composition of these products is mandatory. In this work, the phenolic compounds from commercial samples of chia seed, fiber flour and oil were extracted using an ultrasound-assisted methodology and were separated and identified by high-performance liquid chromatography coupled to a mass spectrometer. Methanol:water extracts were prepared and submitted to an acidic hydrolysis. Crude and hydrolyzed extracts were analyzed and phenolic compounds found were mainly caffeic acid and danshensu and its derivatives, such as rosmarinic and salvianolic acids. TPC was higher in the hydrolyzed extracts. These results supply new information about the main phenolic compounds presents in chia, which are important dietary sources of natural antioxidants for prevention of diseases caused by oxidative stress.

Syzygium malaccense is poorly studied regarding the bioactive compounds of fruits and leaves. The aim of this study was to determine proximate composition, phenolic compounds, carotenoids, and antioxidant capacity of the fruit parts and leaves of S. malaccense . The samples were extracted with different solvents in order to analyze phenolic compounds content (Folin-Ciocalteau and HPLC-DAD/FLD), flavonoids (reaction with AlCl 3 and HPLC-DAD/FLD), anthocyanins (differential pH and HPLC-DAD, UPLC-ESI-MS/MS), total carotenoids (colorimetric method) and antioxidant capacity (hydrophilic and lipophilic-ORAC, FRAP, DPPH). The pulp demonstrated high amounts of soluble fibers and reducing sugars. The peel, seeds and leaves of S. malaccense showed great contents of phenolic compounds, flavonoids and carotenoids as well as antioxidant capacity. The anthocyanins found in the fruit were cyanidin-3- O -glucoside, cyanidin-3,5- O -diglucoside, and peonidin-3- O -glucoside. Polar bioactive compounds showed strong correlation to hydrophilic antioxidant capacity, while carotenoids did not correlate lipophilic-ORAC.

A adicao de corantes em alimentos possui implicacao direta no aceite ou nao do respectivo alimento, apesar de conferir cor, o uso destes aditivos pela industria tem sido bastante questionado do ponto de vista toxicologico devido a sua capacidade nociva ao ser humano. Para evitar problemas a saude humana, metodos analiticos devem ser desenvolvidos com a finalidade de validar e garantir seguranca no consumo de alimentos No presente trabalho sera analisado resultados obtidos na determinacao de corantes artificiais em bebidas alcoolicas e nao alcoolicas atraves da tecnica de Cromatografia a Liquido de Alta Eficiencia (CLAE).

O caramelo classe IV é um corante de uso difundido em diversos produtos, principalmente refrigerantes. Durante o seu processamento podem ser gerados compostos com possível potencial cancerígeno, o 2-metil-imidazol(2-MEI) e 4-metil-imidazol(4-MEI). Assim, estudos sobre esses compostos e o desenvolvimento de metodologias, são de suma importância. Através da cromatografia líquida de alta eficiência é possível identificar e quantificar esses compostos. A metodologia desenvolvida foi validada, portanto os resultados podem ser aceitos. Entretanto, nas 8 amostras de refrigerante de cola e nas 4 amostras de refrigerante guaraná, as substâncias não foram detectadas.

Resumo Componentes como açúcares e ácidos clorogênicos, que são acumulados durante a maturação dos grãos de café, possuem importante papel na qualidade da bebidanão somente atribuído a sua alta concentração, mas também às alterações ocorridas nos grãos durante a torração. Os açúcares predominantes nos grãos de café são frutose, glicose e sacarose. Porém, os ácidos clorogênicos podem ser responsáveis pela desvalorização na qualidade da bebida, devido à intensa degradação térmica durante o processamento dos grãos. Este estudo teve como objetivo avaliar a composição química destas duas substâncias durante as etapas pós-colheita em cafés colhidos em diferentes estádios de maturação, pela técnica de Cromatografia Liquída de Alta Eficiência (CLAE). Com relação aos monoisômeros dos ácidos clorogênicos, o teor de 5-acido cafeoilquinico (5-CQA) teve aumento durante o processamento dos grãos, apesar de ter se mantido instável durante as etapas de secagem em terreiro. Os três lotes estudados foram: Lote 1, representado por 90% frutos cereja + 10% frutoscru; Lote 2, frutos 100% cereja; e Lote 3, 85% frutos boia + 10% frutos cereja + 5% frutos cru. Esses lotes diferiram significativamente entre si com relação ao teor de 5-CQA. Com referência ao lote 2, este foi o lote que apresentou a maior concentração de 5-CQA, por outro lado, durante o processo de torração e elaboração da bebida, ocorreu redução no teor de 5-CQA. Os teores dos isômeros 3 e 4 não apresentaram uma tendência definida de aumento ou diminuição durante o processamento. Com relação aos açúcares, uma maior concentração de sacarose foi encontrada no lote 3. Ainda vale ressaltar que o teor de sacarose teve um aumento durante o processamento, enquanto os teores de frutose e glicose teve uma diminuição. Após a torração, os níveis de sacarose, frutose e glicose diminuíram significativamente, e não houvedetectação tanto de glicose quanto de frutose nos grãos torrados. O método escolhido para a determinação dos açúcares e ácidos clorogênicos foi considerado eficiente diante dos resultados obtidos durante a validação dos métodos. Abstract Compounds such as sugar and clorogenic acids, accumulated during the ripening of coffee beans, have an important role in beverage quality, which is ascribed not only to their high concentration, but also to the changes occurring during roasting. The predominant sugars present in coffee beans are glucose, fructose and sucrose. Chlorogenic acids may be responsible for a loss in beverage quality, since they suffer intense thermal degradation during bean processing. The objective of this study was to evaluate the behaviour of the chemical compounds during the post-harvest steps in coffees harvested at different ripening stages, using High Performance Liquid Chromatography (HPLC). With respect to the chlorogenic acid monoisomers, the 5-CQA content tended to increase during the bean processing, despite being unstable during sun drying. The three batches studied (batch 1: 90% cherry + 10% unripe; batch 2: 100% cherry; batch 3 85% floaters + 10% cherry + 5% unripe) presented significantly different 5-CQA contents, batch 2 presenting the highest concentration. During the roasting process and elaboration of the beverage, a reduction in the 5-CQA contents occurred. The levels of the isomers 3 and 4 showed no defined tendency to increase or decrease during processing. With respect to the sugars, the sucrose content tended to increase and the fructose and glucose contents decreas during processing. A higher concentration of sucrose was found in batch 3. After roasting, the levels of sucrose, fructose and glucose decreased drastically, glucose and fructose not being detected in the roasted beans. The method chosen to determine the sugar and clorogenic acid contents was considered efficient during validation of the methods, due to the results obtained.

The bioactive compounds of freeze-dried jaboticaba peel (FJP), serum lipids and the antioxidant status of rats fed high-fat diets containing different doses of FJP were evaluated. Obesity was induced and three groups of the obese animals received high-fat diet with 1%, 2% and 4% FJP added (J1, J2 and J4, respectively). The HPLC–DAD analyses of the polyphenols in the FJP showed four compounds: gallic acid, cyanidin 3-glucoside, ellagic acid, and quercetin. The serum saturated fatty acids were reduced in J1 and J4-fed animals. The antioxidant defenses of plasma were increased in the J2 and J4-fed animals. All the FJP diets prevented lipid peroxidation in the liver and increased its antioxidant defenses. Lipid peroxidation in brain decreased with an increasing FJP content in the diet. The antioxidant status of the kidneys of J2 and J4-fed animals increased. Thus, FJP could be an alternative to minimize the high-fat diet-induced oxidative stress and circulating saturated lipids.

The consumption of tea increased significantly in the past few years as a result of its health benefits as potent antioxidants in the diet. However, studies on the antioxidant compounds from Brazilian tea are scarce. Thus, the aim of this work was to evaluate the total phenolic compounds (TPC) and total flavonoids (TF) contents and the antioxidant capacity (DPPH and β-carotene/linoleic acid system) of nine herb infusions from the Amazonian region, namely agiru (Chrysobalanus icaco), acoita-cavalo (Luehea speciosa), capim-santo (Cymbopogon citratus), erva-cidreira (Lippia alba), graviola (Annona muricata L.), juca (Libidibia ferrea), pata-de-vaca (Bauhinia ungulata), pariri (Fridericia chica) and sacaca comum (Croton spp.). These herbs were chosen based on popular knowledge and consumption. C. ferrea (68.13 mg GAE/g), L. speciosa (47.54 mg GAE/g) and C. icaco (51.30 mg GAE/g) presented the highest TPC contents, while L. speciosa (12.85 mg CE/g) and L. alba (15.42 mg CE/g) showed the highest TF contents. The highest antioxidant capacity, using both assays, was shown by L. ferrea. The three herbs with the highest TPC contents were selected to be analyzed by high performance liquid chromatography (HPLC) coupled to a diode array detector (DAD). A commercial green tea (Camellia sinensis) was also analyzed as a reference. The main compounds tentatively identified were gallic acid (0.45 mg/g), myricetin (0.78 mg/g) and quercetin (0.14 mg/g) in C. icaco; (+)-catechin (1.20 mg/g) and quercetin (0.14 mg/g) in L. speciosa; gallic acid (0.59 mg/g) and quercetin (0.13 mg/g) in C. ferrea; and gallic acid (0.24 mg/g), (−)-epicatechin (2.44 mg/g), (+)-catechin (0.68 mg/g) and quercetin (0.66 mg/g) in green tea. Among the nine studied herbs, the importance of L. ferrea should be pointed out since it presented the highest TPC content and antioxidant capacity and its gallic acid content was much higher than that of green tea.

Passiflora alata Curtis (P. alata) leaves have anti-inflammatory properties; the present study aimed to investigate the anti-diabetogenic properties of P. alata aqueous leaf extract. HPLC analysis identified the phenolic compounds catechin, epicatechin and rutin. The aqueous extract was administered for 30weeks to non-obese diabetic (NOD) mice presenting a decrease of 28.6% in diabetes incidence and the number of inflammatory cells in pancreatic islets, when compared with the control group (water). The P. alata group presented an antioxidant effect and decreased lipid peroxidation in the serum of NOD mice. Increased numbers of insulin-positive cells were also observed in the pancreatic islets of the treated group. The diabetic group exhibited higher levels in the glucose tolerance test and glycemic index, in comparison to the P. alata-treated group and non-diabetic control BALB/c mice. In addition, the P. alata extract reduced the percentage and the proliferation index of NOD mice lymphocytes submitted to in vitro dose/response mitogenic stimulation assays. These results suggest that the aqueous extract of P. alata has anti-inflammatory properties, contributing to the protection of beta cells in pancreatic islets in NOD mice, and presents potential for use a supporting approach to treat type 1 diabetes.

Racional: Helicobacter pylori é responsável por várias doenças gastrointestinais. Com o aumento de cirurgia bariátrica no país, há poucos estudos sobre a prevalência desta bactéria em obesos com indicação cirúrgica e o seu papel no surgimento de lesões inflamatórias no pós-operatório. Objetivo - Identificar a incidência de lesões inflamatórias no estômago pós-cirurgia bariátrica e correlacionar com a infecção por H. pylori. Métodos - Estudo prospectivo com dois grupos de pacientes. Em ambos os grupos verificou-se a prevalência do H. pylori no pré-operatório através de histopatologia, mas em apenas um dos grupos, nos casos de H. pylori positivo realizou-se o tratamento com antibioticoterapia e inibidor de bomba de próton com realização de nova endoscopia no 6° e 12° mês pós-operatório. Resultados: Avaliou-se 216 pacientes, com as seguintes características: sexo feminino (68,1%), faixa etária entre 30-40 anos, com 31,9% e 31%, respectivamente. De acordo com o IMC, 17,6% apresentavam obesidade moderada, 82,4% obesidade severa/mórbida e 9,7% superobesidade. Nos pacientes submetidos à endoscopia, a positividade do H. pylori se manifestou em 40,7%, sendo responsável pela atividade inflamatória na mucosa gástrica (p

Optimization of the extraction methodology for antioxidant phenolic compounds in red grape jam was performed with an ultrasound-assisted system. The antioxidant phenolic compounds were extracted and analyzed by determining the total phenolic content (Folin Ciocalteu), as well as by employing free radical DPPH and the beta-carotene/linoleic acid system. To optimize the parameters of solvent concentration, time and extraction temperature, the experiments were carried out using the central composite rotatable design (CCRD) method. Using response surface methodology (RSM), the best combinations achieved were with 60% ethanol and water for 20 min at 50 °C. The optimized parameters for this method were compared to an extraction method that has been commonly noted in the literature, which used to be the standard method, and the results were expressed in the milligram equivalent of quercetin per gram of jam (mg E.Q/g Jam). With the new method, the antioxidant potential measured by DPPH was 70% higher than that obtained with the standard extraction method, and the antioxidant potential measured using the beta-carotene/linoleic acid system was 65% higher. In addition, a significant decrease in the total analysis time was achieved (from 10 h to 30 min), when compared to the standard method.

Ascorbic acid has important nutritional characteristics such as high antioxidant potential, preventing diverse damage and diseases in the tissues and the process of aging. Different isomeric forms of the ascorbic acid can be found in nature and each one have different potential antioxidant and different activity pro-vitamin C. This work examined a method to detect and quantify the isomers L-ascorbic acid (LAA) and D-iso-ascorbic acid (DIAA) in jelly fruit. The method showed acceptable selectivity, linearity, repeatability and recovery. DIAA was not found in the analyzed samples, but LAA was found up to 605 mg in 100 g of sample.

Multiple response simultaneous optimisation was used to develop a micellar electrokinetic chromatography method for caffeine determination in decaffeinated coffees. Buffer composition and voltage were optimised using a central composite design. Six responses were evaluated and each set of response values was regressed on the factor levels of the experimental design using linear and quadratic models. The regression models, correlation coefficients and a principal component analysis (PCA) were used to determine the optimum conditions. Successful results were obtained using a buffer containing 10 mmol L −1 sodium carbonate and 50 mmol L −1 sodium dodecylsulfate, 15 kV voltage, 25 °C temperature, 48 cm × 50 μm fused-silica capillary, hydrodynamic injection of 50 mBar during 7 s and detection at 206 nm. This optimised method was applied for caffeine analysis in 45 samples of commercial decaffeinated coffee.

This work reports the use of multivariate calibration models to determine energy values (EV) of industrialized dried vegetable products prepared for human consumption. These methods use energy dispersive X-ray fluorescence spectra allied to chemometrics of the respective samples to substitute conventional EV determinations that are subject to several laborious steps. The samples are grouped in accordance with their principal raw material (corn, wheat, soy, milk and cassava). The chemometric tools applied reveal that the X-ray scattering spectrum region furnishes the main contribution to the calibration models, where the presence of organic compounds is manifested through small variations in X-ray scattering effects. These results are expected because EV values are based on the organic contents. The EV determination is fast, does not generate residuals and does not involve toxic reagents. The good results of the validation process (deviations < 14%) indicate that this is an alternative to conventional analytical methods and is very attractive for routine analysis. Copyright © 2010 John Wiley & Sons, Ltd.

A metodologia indicada pela AOAC para a determinação de Vitamina C em sucos e preparados emprega uma titulação com o indicador 2,6-diclorofenol-indofenol. Esta técnica apresenta dificuldades quando são analisadas amostras com intensa coloração. Tendo em vista a necessidade de uma metodologia mais adequada para estas amostras, foram feitas modificações no método tradicional e sua eficácia foi comprovada. Testes comparativos foram realizados entre a metodologia original, a modificada e um método cromatográfico. Seis diferentes geleias de frutas foram analisadas e as modificações propostas foram satisfatórias, ao passo que os resultados foram mais semelhantes aos obtidos pelo método cromatográfico. O sistema apresentou-se linear, repetitivo (desvio padrão de 2,50%), com alta recuperação (102,10%), e uma economia de 92,88% de reagentes foi realizada. Foram encontradas concentrações entre 0 a 6,08 mg de ácido ascórbico por 100 g de amostra.The AOAC standard methodology for determination of vitamin C in juices and preparations employs a titration with the indicator 2,6-di-chlorophenol-indophenol. This technique presents difficulties when samples with intense coloration are analyzed. Considering the need for a more adequate methodology to deal with these samples, adaptations of the traditional method were performed and their efficacy was verified. Comparative tests were performed on the standard methodology, the modified methodology and the chromatography method. Six different jelly fruits were analyzed and the proposed modifications were considered satisfactory, because these results were closest to the chromatographic results. The system proved to be linear, repeatable (standard deviation of 2.50%), with high recovery (102.10%) and an economy of 92.88% of reagents was achieved. Concentrations were between 0 to 6.08 mg of ascorbic acid per 100 g of sample.

The Energy Value (EV) corresponds to the sum of the energetic contributions from food macronutrients (proteins, carbohydrates and fats) and is required on the labels of pre-packaged foods. The determinations of these parameters are based on distinct analytical procedures, each one being time-consuming, laborious and producing residues. This work presents multivariate models to determine the EV contents of industrialized foods for human consumption by using X-ray fluorescence spectra of samples with known parameters, determined through conventional methods. The proposed method is an alternative to conventional analytical methods and does not require any reagent, given the demands of the "green chemistry".

Synthetic dyes are much used in processed foods. HPLC was applied to different types of snacks, such as colored cereals, chocolate confetti, chewing gums and candies for the determination of those additives. In the case of artificially colored breakfast cereals, 71% of the samples exceeded the allowed limits. Regarding the portions recommended for consumption by the makers of two of the samples, the amounts exceeded those allowed by the Brazilian legislation. In the case of chocolate confetti and candies none of the samples showed higher amounts than those allowed. However 37% of the chewing gum samples presented larger contents than the authorized ones, and one sample contained five times more synthetic dyes than allowed.

Medical and folklore reports suggest that Eugenia uniflora (E. uniflora) is a functional food that contains numerous compounds in its composition, with anti-inflammatory, antioxidant and anti-diabetic effects. In the present study, we investigated the best solvents (water, ethanol and methanol/acetone) for extracting bioactive compounds of E. uniflora leaves, assessing total phenols and the antioxidant activity of the extracts by 2,2-Diphenyl-1-picrylhydrazyl (DPPH), Ferric Reducing Antioxidant Power (FRAP), 2,2′-Azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and Oxygen Radical Absorbance Capacity (ORAC) assays, identifying hydrolysable tannins and three phenolic compounds (ellagic acid, gallic acid and rutin) present in the leaves. In addition, we evaluated the incidence of diabetes, degree of insulitis, serum insulin, hepatic glutathione and tolerance test glucose in non-obese diabetic (NOD) mice. Our results suggest that the aqueous extract presents antioxidant activity and high total phenols, which were used as a type 1 diabetes mellitus (DM-1) treatment in NOD mice. We verified that the chronic consumption of aqueous extract reduces the inflammatory infiltrate index in pancreatic islets, maintaining serum insulin levels and hepatic glutathione, and reducing serum lipid peroxidation as well as the risk for diabetes.

The jaboticaba (Myrciaria jaboticaba (Vell.) Berg) peel was lyophilized and the proximate composition, total anthocyanins and polyphenolic content were determined. The effect of the freeze-dried jaboticaba peels (FJP) in the plasmatic levels of glucose, lipid fractions, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in Wistar adult male rats was investigated. The animals were distributed in four groups G0 (control), G1, G2, G4, which received 0, 1, 2 and 4% FJP powder added to normal diet, respectively. The chemical analyses showed that FJP is a source of fiber, anthocyanins, gallic and ellagic acids. The FJP supplementation was responsible for a reduction in the plasmatic glucose levels in G2 group. Total triglycerides and cholesterol levels were reduced in the G1 animals as compared to G0, but the animals treated with 2 and 4% FJP showed increased total cholesterol level and LDL-cholesterol fraction. HDL-cholesterol and hepatic probes showed no significant changes in the experimental groups G1, G2 and G4 in comparison to G0.Keywords: Polyphenols, glucose and cholesterol levels, Jaboticaba, Myrciaria jaboticaba (Vell.) Berg.African Journal of Biotechnology, Vol 13(37) 3805-3811

Copaifera langsdorffii (copaiba) is a Brazilian exotic fruit, poorly studied regarding its bioactive composition. The aim of this study was to determine bioactive compounds, antioxidant and antimutagenic activities of copaiba pulp. The samples were extracted with different solvents in order to analyze polyphenol compounds (Folin Ciocalteau and HPLC-DAD), total flavonoids (reaction with AlCl3) and antioxidant capacity (FRAP, ORAC, DPPH). The copaiba fruit showed high polyphenol content and antioxidant capacity. Phenolic compounds, such as gallic acid, epicatechin gallate, catechin, epicatechin and isoquercitrin, were identified in the copaiba pulp. Despite the antioxidant capacity, the highest dose of copaiba showed no antimutagenic effects in the in vivo study. The dose which showed antimutagenic activity was 100 mg kg(-1).

In this work a method of analysis for synthetic dyes was developed using capillary electrophoresis in alcoholic beverages. The analyses were carried out with fused silica capillary, with 73 cm effective length, at 35 degrees C, buffer phosphate solution of 10 mmol/L with sodium dodecyl sulphate 10 mmol/L, pH 11, and +25 kV of voltage. For dye analyses, three wavelengths in the visible region were used for the qualitative and quantitative determination of the 11 synthetic dyes allowed in Brazil: 450, 525 and 625 nm for the yellow, red and blue dyes, respectively. The detection limits varied from 0.4 to 2.5 microg/mL and the quantification limits varied from 1.3 to 7.1 microg/mL. The average recovery was 92.6 and 104.0% at two levels of concentration. Repeatability for standards and spiked sample showed that the calculated values were greater than the observed values, demonstrating the precision of the method. The proposed and validated method was used to analyze some alcoholic beverage samples, consisting of 12 red wines, 9 coolers, 6 aromatized spirits, 7 bitters, 3 cocktails and 8 liquors from different Brazilian manufacturers. The results showed the coolers, bitters and red wines did not have synthetic dyes, but dyes were found in six of the eight analyzed liquor samples. In all the samples of cocktails and spirits, the presences of dyes were observed. No analyzed sample exceeded the limit established by Brazilian legislation (maximum 30 mg/100 mL).

Synthetic dyes are added to foods due to the many changes which alter or destroy the natural colors of the products during processing and/or storage, and principally to increase the acceptance of the product, by the customer. Synthetic dyes show several advantages over natural pigments. The lack of adequate analytical methodology has made it difficult to control the levels of coloring agents in foods. Also, there is no methodology capable of responding to the size and the demand for such analyses by the industrial sector, in several types of food. This work, proposed and validated a methodology for the simultaneous determination of the eight synthetic colors: Sunset yellow [E-110], yellow n°5 [E-102], bordeaux S [E-123], red n°40 [E-129], red n°17 [E-124], red n°3 [E-127], brilliant blue [E-133] and indigo carmin [E-132], allowed in foods in Brazil, using the technique of high performance liquid chromatography (HPLC). The dye was extracted with warm water (40 to 50°C), the solution was centrifuge...

The objective of this research was to determine the levels of enrichment of vitamins B1, B2, B6 and B3 in different types and brands of enriched cookies. The chromatographic separation was performed in a C18 column with gradient elution and UV detection at 254 and 287 nm. The results show that only 5 of the 24 brands evaluated are in accordance with the Brazilian legislation with respect to the vitamin content declared on the labels. However, consumption of approximately 100-150 g of most of the brands supplies the recommended dietary intake for children and adults of the vitamins evaluated.

Synthetic dyes were determined by high performance liquid chromatography in 76 samples of regular jelly and diet jelly powders, of several flavors produced by seven different manufacturers. Three sample of each product, from different batches, were analyzed. The same qualitative composition was observed for products of the same flavor from different manufacturers, but the quantitative composition varied markedly from one manufacturer to the other. There were no or few significant differences between batches from a given manufacturer, demonstrating good quality control in the use of these additives by the food industry. None of the samples exceeded the limit stipulated by Brazilian legislation.

Orientador: Helena Teixeira Godoy Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos Resumo: O controle dos níveis de corantes artificiais utilizados em alimentos não é um procedimento rotineiro, especialmente, peia falta de metodologia adequada capaz de responder à demanda do número de análises e a determinações quantitativas nos mais variados tipos de alimentos, além de se tornar viável para implantação nos laboratórios de controle de nosso pais. Visando superar esse problema, foi desenvolvida e avaliada unia metodologia para a determinação qualitativa e quantitativa dos oito corantes artificiais, permitidos para a utilização em alimentos pela legislação brasileira, utilizando a técnica de cromatografia a líquido de alta eficiência (CLAE). O método desenvolvido foi aplicado na detenninação dos corantes tartrazina, amarelo crepúsculo, amaranto, ponceau 4R, vermelho 40, eritrosina. azul indigotina e azui brilhante, em 10 (dez) diferentes tipos de produtos alimentícios, como pós para gelatina, refrescos em pó, refrigerantes, bebidas isotônicas, sucos concentrados artificiais, sucos natural de frutas, cereais matinais coloridos, baias, gomas de mascar e confeitos. Principalmente, em relação aos métodos oficiais e outros empregados, as vantagens da nova metodologia podem ser resumidas, além da determinação simultânea dos 8 (oito) corantes, na simplicidade da etapa de extração, na utilização de reagentes mais comuns e com menores níveis de toxidade, na eluição isocrática e na nào necessidade do uso de pares iónicos na fase móvel Todos esse parâmetros em conjunto tornaram a análise rápida, além de alta reprodutibilidade, característica inerente à técnica empregada. Os corantes são extraídos com água aquecida a 40-50°C. As amostras de os cereais matinais os corantes são extraídos com solução amoniacal (10% em etanol). Bebidas isotônicas e refrigerantes são apenas degaseiftcados. Após o ajuste do volume com água, uma pequena porção é coletada e centrifugada a 15.000 rpm por um período de 10 minutos. O sobrenadante é filtrado em filtro fluopore FHLP 01300 de 0,5 µm e injetado no cromatógrafo. O condicionamento da coluna, realizado peta passagem de uma solução de água/metanol (70:30) + 0.08M de acetato de amônio, por 12,5 minutos, entre cada injeção, é importante para a obtenção de uma boa resolução entre os corantes. Após o condicionamento d a coluna, ocorre uma mudança de fase móvel, apenas com a retirada do acetato de amônio, e os corantes são eluidos em 20 minutos de corrida. A detecção é feita na região do visível, com a utilização de um detector de arranjo de díodos, e a quantificação é feita através de curvas de padronização externa. Os limites de detecção e recuperação foram respectivamente: 0,51 µg/mL e 96.3% para o azul de indigotina; 1.30 µg/mL e 98.2 % para o azul brilhante; 1.02 µg/mL e 102% para o amaranto; 0,57 µg/mL e 96,8 % para o ponceau 4R; 1.10 µg/mL e 100.3 % para o vermelho 40; 0.51 µg/mL e 96 % para a eriírosina; 0.70 µg/mL e 99,7% para a tartrazina e 1.83 µg/mL e 98.9 % para o amarelo crepúsculo. Entre os alimentos analisados, as misturas de pós para gelatina, bebidas isotônicas, refrigerantes, sucos concentrados artificiais e confeitos de chocolate estavam abaixo do limite quantitativo estabelecido pela legislação brasileira, de 10mg/100g ou 10mg/100mL, entretanto, todo as as amostras de cereais matinais coloridos apresentaram níveis superiores a esses limites. Trinta e sete por cento das amostras analisadas de preparados sólidos para refresco, 63% das gomas de mascar, 30% das balas duras e 18% das balas mastigáveis tiveram o conteúdo de corantes acima do permitido. Nas amostras de sucos naturais de frutas não foi observada a presença de corantes sintéticos. Apenas algumas amostras de refresco em pó, goma de mascar e confeitos de chocolate apresentaram mistura de mais de três corantes, Em nenhuma das amostras analisadas foi observada a presença de corante não permitido. Os resultados obtidos neste trabalho, além de demonstrarem as vantagens e aplicabilidade da metodologia desenvolvida, aponta para a necessidade de maior rigor no controle dos níveis de corantes artificiais nos alimentos Abstract: The control of level of synthetic dyes food isn't a routine procedure, specially by the lack of adequate methodology capable of answering the demand of the number of analyses and the quantitatives determination in the most different kinds of food, besides making available to the implantation in control labs in our country. Trying to overcome this problem, it was developed and avaliated a methodology to a qualified and quantified of eight artificial colorants allowed to be used by the brazilian legislation, using the technique of high performance liquid chromatography (HPLC). The developed method was applied in the determination of the yellow n° 5, sunset yellow, bordeaux S, red n° 17, red n" 40, red n° 3, indigo carmin and brilliant blue coloring, in ten different kinds of food products, as jelly powder, soft drinks, isotonic drinks, artificially concentrated juice, natural fruit juice, mormning colored cereals, candies, chewing gums and sweet. Most of all, in relation to the offial methods and other used ones, the advantage of the new technology can be resumed, besides the simultaneous determination of the eight colors, in the simplicity at the point of extraction, in the use of more common reactors and with lower levels of toxicity, in the isocratic elution and on the no need of using ionic pairs in the mobil fase. All these parameters in group become the analyses quick, besides the high reprodutivety, intrinsical characteristic to the used technique. The coloring were taken with heated to 40 - 50° C. For the samples of the morning cereals the colouring were taken with the amonicat solution (10% in ethanol) Isotonic drinks and soft drinks were only ungasified. After the adjustment of the volume with water, a small portion was collected and untrifuged to 15,000 rpm for a period often minutes. The surface was filtered in a fluopore filter FHLP 01300 of 0.5 cm and put in the chromatography. The regulation of the column done by the fluid of a solution of water/methanol (70/30) + 0.08 M of ammonium acetate, by 12.5 minutes, between each injection, is important to the obtainance of a good resolution among the coloring. After the regulation of the column, there was a change in the motive fase, only with removal of the ammonium acetate, and the coloring were eluted in a 20 minute race. The detection was made in the visible region, with the help of a diode array detector and the quantification was done through the curves of outside padronization the limits of detection and recuperation were respectively 0.51 µg/ml and 96.3% to the indigo carmin, 1.30 µg/ml and 98.2% to the brilliant blue , 1.02 µg/ml and 102% to the bordeaux S, 0.57 µg/ml and 96.8% to the red n° 17, 110 µg/ml and 100.3% to the red nº 40, 0.51 µg/ml and 96% to the red n°3 , 0.70 µg/ml and 99.7% to the yellow n° 5 and 1.83 µg/ml and 98.9% to the sunset yellow. Among the tested food, all the samples of jello powder, isotonic drinks, concentrated artificial price and chocolate sweet were beyond the quantified established by the brazilian legislation, of 10mg/100g, although, all the samples of morning colored cereal showed higher levels to these limits 37% of the analyzed samples of solid preparation to refreshment, 63% of the chewing gum, 30% of the hard candies and 18% of the chewing candies had the coloring containing above allowed. The results obtained in this work, besides showing the advantages and application of the developed methodology, aim to the necessity of bigger severity in the control levels of synthetic dyes in food Mestrado Mestre em Ciência de Alimentos

No presente trabalho foram estudadas as separações de 18 flavonóides (9 agliconas e 9 glicosídeos) pelas técnicas de Cromatografia Líquida de Alta Eficiência em fase reversa (RP-HPLC) e Cromatografia Micelar Eletrocinética em fluxo reverso (RF-Meck). Em ambas as técnicas foram avaliados solventes puros (metanol, acetonitrila e tetrahidrofurano) e suas misturas como formas de promover a variação de seletividade, através da modificação da fase móvel em HPLC, e da natureza do aditivo orgânico em RF-Meck. Nos estudos efetuados em HPLC utilizando-se gradiente, pode-se comprovar a possibilidade da modelagem do fator de retenção em funçã da proporção de solvente utilizados (MeOH, ACN, THF e suas misturas). Pode-se ainda, com base nos dados de retenção e na análise hierárquica de c1usters, diferenciar quatro diferentes grupos de sistemas cromatográficos com diferentes seletividades para flavonóides agliconas, e outros quatro com diferentes seletividades para glicosídeos. Os sistemas cromatográficos mais ortogonais (cada um pertencente a um grupo de seletividade) foram aplicados na separação de uma planta modelo (Azadirachta indica), de onde pode-se escolher a fase móvel mais seletiva para se otimizar a separação dos flavonóides glicosilados presentes nas folhas desta planta. No método final otimizado pode-se identificar e quantificar cinco dos flavonóides majoritários presentes, sendo três glicosídeos de quercetina (rutina, isoquercitrina e quercitrina) e dois glicosídeos de kaempferol (astragalin e nicotiflorin), em amostras de duas diferentes procedências (Piracicaba-SP e Silvânia-GO). Nos estudos envolvendo a separação dos dezoito flavonóides por RFMEKC pode-se comprovar diferenças significativas de seletividade quando se varia a natureza do solvente orgânico utilizado como aditivo, além de se observar tendências na migração em função das propriedades do solvente adicionado e da estrutura molecular do flavonóide. O solvente de menor eficiência para separação dos flavonóides foi o MeOH. Através da análise dos eletroferogramas obtidos através de um planejamento experimental de misturas, e das trocas de pares críticos observadas nos vários eletrólitos utilizados, obteve-se um método de separação com apenas um par crítico em menos de 12 minutos de corrida. O coeficiente de variação obtido para o fator de retenção foi de 1,5% e para área de 3%, considerando-se cinco injeções. O método desenvolvido foi aplicado com sucesso na identificação dos flavonóides majoritários presentes na planta modelo (Neem), obtendo-se o mesmo resultado do estudo anterior. Como forma de avaliar a concentração de flavonóides totais presentes em espécies vegetais é comum a análise de extratos após hidrólise ácida (conversão de todos glicosídeos em agliconas). Desta forma otimizou-se uma metodologia de separação em RP-HPLC de 8 flavonóides agliconas comumente presentes em alimentos e extratos vegetais de uso cosmético. A otimização foi efetuada mediante um planejamento experimental de misturas, para escolha da fase móvel mais seletiva, e de um planejamento fatorial composto central, para otimização das condições de gradiente. O método obtido foi o mais rápido já visto dentro da literatura consultada. A separação em linha de base foi efetuada em menos de 15 minutos, com coeficientes de variação de área entre 0,1 e 1,8%, coeficiente de correlação de 0,9993 a 0,9994 na faixa de 5 a 100 µg/mL, e limites de quantificação estimados na faixa de 0,1 a 0,21µg/mL. O método desenvolvido foi aplicado na otimização das condições de hidrólise de um extrato de Neem. A otimização foi efetuada através de metodologia de superfície de resposta, levando-se em consideração a concentração de ácido adicionada, o tempo de reação, a temperatura, e a concentração de um antioxidante (ácido ascórbico) adicionado. O resultado da otimização foi uma metodologia de hidrólise com tempo de reação igual a 5 minutos, utilizando-se 1,4 mol/L de HCI, 119°C e 500 µg/mL de ácido ascórbico. Através das metodologias de análise e de hidrólise desenvolvidas pode-se constatar a presença e quantificar no extrato de Neem os flavonóides agliconas quercetina, kaempferol e miricetina. Com o objetivo de se avaliar quais os componentes presentes em extratos vegetais são os responsáveis pelo poder antioxidante atribuído a determinadas plantas, foi montado um sistema de avaliação de poder antioxidante \"on-line\" com reação pós-coluna em HPLC (baseado na literatura) utilizando-se como \"radical livre modelo\" o ABTS. A análise da planta modelo (Neem) neste sistema mostrou que os flavonóides glicosilados identificados nas partes anteriores deste trabalho são os responsáveis pelo poder antioxidante atribuído a esta planta. De posse desta informação, e visando a obtenção de extratos para aplicações cosméticas com poder antioxidante, modelou-se a extração dos flavonóide do Neem em função da composição do solvente extrator (água, etanol , propilenoglicol e suas misturas), de acordo com um planejamento simplex centróide ampliado. Além da previsão da concentração dos princípios ativos pode-se ainda prever outras propriedades dos extratos obtidos, tais como, índice de refração e densidade, muitas vezes constituintes de especificações técnicas de acordo com as aplicações a que se destinam (cremes, xampús, etc). At this work, separation of 18 flavonoids (9 aglycones and 9 glycosides) using High Performance Liquid Chromatography (HPLC) and Reduced Flow Micellar Electrokinetic Chromatography (RF-MEKC) were evaluated. For both techniques, pure solvents (methanol, acetonitrile and tetrahydrofuran) e their mixtures were evaluated as an approach of varying selectivity by changing mobile phase in HPLC and organic additive type in RF-MEKC. For HPLC studies using gradient elution, it was possible to guarantee the modeling for retention factor in function of organic solvent used (methanol, acetonitrile and tetrahydrofuran and theirs mixtures). It can be also confirmed, based on retention data and hierarquical clusters analysis, four different chromatographic groups with different selectivity for flavonoid aglycone, and four groups with different selectivity for glycosides. More orthogonal chromatographic systems (each one belonging to a selectivity group) were applied to Neem (Azadirachta Indica) analysis. From this study, it can be chosen the most selective mobile phase composition and optimize flavonoid glycosides separation present at Neem leaves. Applying optimized method, five major flavonoids can be identified and quantified, three quercetin glycosides (rutin, isoquercitrin and quercitrin) and two kaempferol glycosides (astragalin and nicotiflorin), at two samples from different origins (Piracicaba-SP and Silvânia-GO). For studies regarding eighteen flavonoids separation by RF-MEKC can be proved significant selectivity differences when distinct organic solvent are used as additive. Moreover, it can be noted tendencies in migration behaviour depending of solvent used and molecular structure of flavonoids. The solvent with less efficiency to f/avonoid separation is methanol. Analyzing electropherograms obtained by a design of mixtures and by criticai pairs changes observed in diverse electro/ytes, a separation method with only one criticai pair and 12 minutes run was obtained. Coefficient of variation obtained for retention factor was 1.5% and 3% for area (n=5). Developed method was applied to identify major flavonoids at model plant (Neem) and same results observed at previous work were obtained. In order to evaluate total flavonoid concentration present in a plant is a common approach to analyse extracts after acid hydrolyze (convert ali glycosides to aglycones). A method was optimized to separate 8 flavonoid aglicones by RPHPLC usually present in food and vegetal extracts to cosmetic use. Optimization was performed by a mixture factorial design to select the most selective mobile phase composition and one facto ria I design with central point to optimize gradient parameters. Developed methodology is the faster reported in literature until now. Baseline separation was achieved in less than 15 minutes, with coefficients of variation between 0.1 and 1.8%, correlation coefficient from 0,9993 to 0,9994 at 5-100 µg/mL concentration range and quantification limits from 0.1 to 0.21 µg/mL. Developed method was used to optimize hydrolize parameters for a Neem extract. Optimization was realized by a response surface methodology, having concentration of acid added, reaction time, temperature and antioxidant (ascorbic acid) concentration added as parameters. From this study was developed a hydrolyze methodology with 5 minutes of reaction time, using 1.4 mol/L HCI, 119°C and 500 µg/mL of ascorbic acid. Applying method of analysis and hydrolyze developed at Neem extracts it can be identified and quantified aglicones quercetin, kaempferol and miricetin. Aiming to evaluate which compounds in a vegetal extract have antioxidant activity credited to some plants, an on-line system with post-column reaction was built in HPLC (based on literature), using ABTS as free radical mode!. Neem analysis at this system showed that flavonoid glycosides identified before are the responsible for antioxidant activity described for this plant. Based on this information and intending to obtain vegetal extracts with antioxidant activity for cosmetic use, Neem extraction procedure was modeled in function of solvent mixture used (water, ethanol, propylene glycol and their mixtures), following a simplex centroid designo Besides the concentration of active components prediction it can also be predict other properties like refractive index and density, properties that might be included at technical specifications depending of the intended use (creams, shampoos, etc).

Syzygium malaccens e is poorly studied regarding the bioactive compounds of fruits and leaves. The aim of this study was to determine proximate composition, phenolic compounds, carotenoids, and antioxidant capacity of the fruit parts and leaves of S. malaccense. The samples were extracted with different solvents in order to analyze phenolic compounds content (Folin-Ciocalteau and HPLC-DAD/FLD), flavonoids (reaction with AlCl3 and HPLC-DAD/FLD), anthocyanins (differential pH and HPLC-DAD, UPLC-ESI-MS/MS), total carotenoids (colorimetric method) and antioxidant capacity (hydrophilic and lipophilic-ORAC, FRAP, DPPH). The pulp demonstrated high amounts of soluble fibers and reducing sugars. The peel, seeds and leaves of S. malaccense showed great contents of phenolic compounds, flavonoids and carotenoids as well as antioxidant capacity. The anthocyanins found in the fruit were cyanidin-3-O-glucoside, cyanidin-3,5- O-diglucoside, and peonidin-3-O-glucoside. Polar bioactive compounds showed strong correlation to hydrophilic antioxidant capacity, while carotenoids did not correlate lipophilic-ORAC.

O estilbeno resveratrol é um composto fenólico potencialmente benéfico à saúde, principalmente devido a sua atividade cardioprotetora. Apesar de abundante em uvas e vinhos tintos, o resveratrol encontra-se ausente na maioria das frutas e vegetais que compõe a dieta humana. Recentemente, este estilbeno foi detectado em cacau e chocolates da Europa e Estados Unidos, configurando-os como sua segunda maior fonte comestível. A escassez de estudos acerca da ocorrência de resveratrol em alimentos consumidos pela população brasileira torna evidente a importância da investigação por fontes que o contenham. Este estudo teve como objetivos avaliar o conteúdo de compostos fenólicos totais, a atividade antioxidante de extratos aquosos e alcoólicos de cacau e derivados produzidos no Brasil, além do teor de resveratrol. Foram analisados 14 produtos que incluíram nibs de cacau, chocolates 70% e 56% de cacau, chocolates meio amargos, ao leite, brancos, achocolatados em pó e bebidas lácteas achocolatadas, de marcas populares do mercado brasileiro. Os compostos fenólicos totais foram quantificados pelo método Folin-Ciocalteu e a atividade antioxidante foi avaliada pelos métodos DPPH, ABTS, FRAP e auto-oxidação do sistema \'beta\'-caroteno/ácido linoleico. A identificação do resveratrol nas amostras foi confirmada pela técnica de cromatografia gasosa acoplada a espectrometria de massas (CG-EM) e a quantificação foi feita pela técnica de cromatografia líquida de alta eficiência (CLAE). Os extratos aquosos apresentaram teores mais elevados de compostos fenólicos totais (mg AG.g-1), na seguinte ordem: nibs de cacau (21,54) > chocolate 70% (10,45) > chocolate 56% (9,51) > chocolates meio amargos (8,15) > achocolatados em pó (5,91) > chocolates ao leite (3,77) > chocolates brancos (1,22) > bebidas lácteas achocolatadas (0,96). A mesma sequência foi encontrada para a atividade antioxidante obtida pelos métodos indiretos, exceto para chocolates brancos, que exibiram os menores potenciais. Os extratos aquosos apresentaram a maior atividade antioxidante, variando de 86,53 a 1,55% pelo método DPPH; 141,27 a 3,2 \'mü\'m trolox.g-1 pelo método ABTS e 354,42 a 2,27 \'mü\'mol Fe++.g-1 pelo método FRAP. Por meio da auto-oxidação do sistema \'beta\'- caroteno/ácido linoleico, os extratos aquosos e alcoólicos mostraram valores similares para atividade antioxidante, a qual foi maior que 70% para nibs de cacau e chocolates 70% e 56%. O estilbeno resveratrol foi identificado em todas as amostras analisadas por CG-EM, entretanto em virtude da presença de teores abaixo do limite de quantificação, não foi possível a sua quantificação na maioria das amostras pela técnica de CLAE. Chocolates meio amargos exibiram os maiores teores de resveratrol, os quais foram superiores aos relatados para os mesmos produtos europeus e americanos. Apesar do cacau brasileiro não estar entre os de melhor qualidade, os resultados obtidos mostram seu elevado potencial antioxidante e de seus derivados, contribuindo para a ingestão de antioxidantes pela população brasileira, dentre os quais o estilbeno resveratrol The stilbene resveratrol is a phenolic compound potentially beneficial to human healthy, mainly due it cardioprotector properties. Despite it abundance in grapes and wines, this stilbene lacks in most fruits and vegetables that compose human diet. Recently, resveratrol was detected in cocoa and chocolates commercialized in Europe and United States, making these products the second edible source of resveratrol. The lack of studies about resveratrol occurrence in Brazilian diet makes evident the need for investigation of the stilbene sources. This study aimed at analyzing the amount of total phenolic compounds, the antioxidant activity of aqueous and methanolic extracts of cocoa and cocoa products from Brazil, and the resveratrol level. A total of 14 products were analyzed, including cocoa nibs, chocolates 70% and 56% cocoa, dark, milk and white chocolates, chocolate Milk beverages and chocolate powders, of popular Brazilian trademarks. The total phenolic compounds were quantified by the Folin-Ciocalteu method. The antioxidant activity was determined using the DPPH, ABTS, FRAP and \'beta\'-carotene bleaching assays. Identification of resveratrol in the samples was confirmed by gás chromatography/mass spectrometry method (GC-MS) and quantification was obtained by high performance liquid chromatography (HPLC). Aqueous extracts showed a higher phenolic content (mg GAE.g-1), following the sequence: cocoa nibs (21,54) > chocolate 70% (10,45), chocolate 56% (9,51), dark chocolates (8,15) > chocolate powders (5,91) > milk chocolates (3,77) > white chocolates (1,22) > chocolate milk beverages (0,96). The same sequence was detected for the antioxidant activity obtained by indirect methods, except for white chocolates, which exhibited the lowest antioxidant activity. Aqueous extracts showed a higher antioxidant activity, ranging from 86,53 to 1,55% in the DPPH assay; 141,27 to 3,2 \'mü\'m trolox.g-1 in the ABTS assay and 354,42 to 2,27 \'mü\'mol Fe++.g-1 in the FRAP assay By the \'beta\'-carotene bleaching method, methanolic and aqueous extracts showed similar antioxidant activities, which were higher than 70% for cocoa and chocolates 70% and 56% cocoa. Resveratrol was identified in all the samples analyzed by GCMS, but its presence below the limit of quantification doesnt allow its determination in all samples by HPLC. Dark chocolates exhibited the highest resveratrol levels, which were higher than those related for the same European and American products. Although Brazilian cocoa isnt recognized for its quality, the results obtained show it high antioxidant activity and of its derivatives, contributing for antioxidants intake by Brazilian population, among them the stilbene resveratrol

The aim of the is work was to manipulate the composition of omega-3 and 6 fatty acids in tilapia (Oreochromis niloticus) that were supplied with diet containing soy and linseed oil during 90 days in order to improve the nutrition potential of Nile tilapia filet, mainly considering the n-3 fatty acid composition. In addition, the neutral lipids (NL) and phospholipids (PL) fractions were separated from the totallipids and, the alpha-linolenic (ALA, 18:3n-3), linoleic (LA, 18:2n-6), cervonic (DHA, 22:6n-3), timnodonic (EPA, 20:5n3) and arachidonic (AA, 20:4n-6) fatty acids were quantified by using the methyl ester of tricosanoic acid (23:0) as internal standard. The experiment was carried out in two metallic cages, each containing 100 tilapias, placed into a natural water course localized in the Guaíra city - PR. Both groups were fed twice a day with ration enriched with 7 % of soybean (group I) or linseed oil (group II). Seven individuais of each cage were collected at the initial time (before the treatment onset) and each 15 days during 90 days. Fish samples were slaughtered, eviscerated, cut into filets, conditioned into nitrogen, and frozen. Then, samples were defrosted and triturated for subsequent chemical analysis. Moisture, ash and total protein were determined following the AOAC methods. Total lipids were extracted by using Bligh & Dyer's method and the preparation of fatty acid methyl esters and their quantification were carried out by using Joseph & Ackman's method. Fatty acid composition of total lipids, phospholipids and neutral lipids were quantified by using gas chromatography equipped with a capillary column of fused silica and a flame ionization detector. The identification of fatty acids was carried out by using the relative retention times of the peaks of standard of methyl ester of fatty acids (FAME) from Sigma, co-elution and equivalent chain length (ECL) values. It was observed a considerable incorporation of fat into the tilapia muscular tissue, mainly in the first 45 days, whereas the moisture, ash and protein levels decreased in the period, without alterations in the meat flavor. The polyunsaturated fatty acids n-3 (PUFA n-3) incorporation, was more effective in the fishes fed with linseed oil, improving several aspects of the meat, such as: increasing of LNA and DHA contents during treatment; increasing of PUFA n-3 sum; reduction of PUFA n-6 sum; increasing the ration PUFA/SFA (saturated fatty acids) and reducing the n-6/n-3 ratios. The same effect was observed to LN and PL contents. O objetivo do presente trabalho foi manipular a composição de ácidos graxos ômega-3 e 6 em tilápias (Oreochromis niloficus) que receberam dietas contendo óleo de soja e linhaça por 90 dias com a finalidade de melhorar o potencial nutritivo do filé de tilápia, principalmente em termos da composição dos ácidos graxos n-3. Ainda, as frações de lipídios neutros (LN) e fosfolipídios (FL) foram separadas dos lipídios totais (LT) e os ácidos graxos alfa-linolênico (LNA, 18:3n-3), linoléico (LA, 18:2n-6), cervônico (DHA, 22:6n-3), timnodônico (EPA, 20:5n-3) e araquidônico (AA, 20:4n-6) foram quantificados usando o éster metílico do ácido tricosanóico (23:0) como padrão interno. O experimento foi realizado em duas gaiolas metálicas, contendo 100 tilápias cada, inseridas em curso de água natural localizado no município de Guaíra-PR. Para amostragem, foram coletados sete indivíduos de cada gaiola antes do início do tratamento e a cada 15 dias até o total de 90 dias. As amostras de peixe foram abatidas, evisceradas, filetadas, acondicionadas em atmosfera de nitrogênio e congeladas. Após, as amostras foram descongeladas e trituradas para posterior análise química. As análises de umidade, cinzas e proteína bruta foram realizadas conforme os métodos recomendados pela AOAC. Os lipídios totais foram extraídos utilizando-se o método de Bligh & Dyer e a preparação dos és teres metílicos dos ácidos graxos e sua quantificação foram realizadas pelo método proposto por Joseph & Ackman. A composição de ácidos graxos nos lipídios totais, fosfolipídios e lipídios neutros, bem como a quantificação dos ácidos graxos foram realizados utilizando cromatógrafo gasoso equipado com coluna capilar de sílica fundida e detectar de ionização de chama. A identificação de ácidos graxos foi feita comparando-se os tempos de retenção relativo dos picos de EMAG das amostras com os dos padrões de ésteres metílicos de ácidos graxos (Sigma), por co-eluição e valores do comprimento equivalente de cadeia (CEC). Foi observada considerável incorporação de gordura no tecido muscular das tilápias, principalmente nos primeiros 45 dias, enquanto os níveis de umidade, cinzas e proteína diminuíram no período, sem alteração no sabor da carne. A incorporação de ácidos graxos poliinsaturados n-3 (AGPI n-3), foi mais efetiva nos peixes que receberam ração com óleo de linhaça, melhorando vários aspectos da carne, tais como: aumento dos teores de LNA, DHA no decorrer do tratamento; aumento do somatório de AGPI n-3; redução do somatório de AGPI n-6; aumento das razoes AGPI/AGS e redução das razoes n-6/n-3. Os mesmos efeitos foram observados nos conteúdos de LN e FL. 112 f