Poly(ε-caprolactone), an aliphatic polyester with biodegradability and cytocompatibility, has been used to create scaffolds for tissue engineering purposes. However, the hydrophobicity and low water absorptivity of poly(ε-caprolactone) reduce cell anchorage on their membranes. Here, poly(ε-caprolactone)-based scaffolds were prepared by electrospinning of poly(ε-caprolactone)-chitosan blend, and poly(ε-caprolactone)-dexamethasone solution. Chitosan and dexamethasone play an essential role to increase the scaffolding performance of poly(ε-caprolactone)-based electrospun membranes. A poly(ε-caprolactone) membrane without chitosan and dexamethasone did not provide satisfactory results to promote cell culture of adipose mesenchymal stem cells (AMSCs). Compared to the poly(ε-caprolactone)-dexamethasone surface, poly(ε-caprolactone)-chitosan membrane imparts better cytoskeletal reorganization, and cell spreading, increasing the strength of cell attachment. Also, poly(ε-caprolactone)-chitosan composite provides strong antimicrobial activity against Pseudomonas aeruginosa (ca. 90% inhibition). Therefore, the poly(ε-caprolactone)-chitosan composite is a better alternative to treat skin diseases and promote skin regeneration than conventional approaches based on dexamethasone.

The developed method (DM) allows to perform experiments in shorter time with reduced amount of sample and reagent for fatty acids (FA) determination in fermented milk samples. Design Expert software was employed to discover the greatest sonication time (7 and 20 min) and concentration for alkaline and acidic reactions (0.70 and 1.5 mol L-1). Validation procedures were applied in yogurt samples with diverse fat content, ranging from 1.22 to 2.83%, being in agreement with acceptable values. Besides, the intraday relative standard deviation (RSD) (1.86%) and interday RSD (4.23%) values confirmed the good accuracy of the proposed method for FA derivatization.

The Mehlich-1 extractor is routinely used to evaluate the bioavailability of metals in soil since it has a high closeness between the amount of these elements absorbed by the plants and those available in soil, as well as being simple and practical to use. Thus, the aim of this work was to improve (optimize) a Mehlich-1 extraction method for evaluating the availability of Cu, Zn, Mn, Ni, Cr and Cd in soil using Box-Behnken type response surface method (RSM). After optimizing the soil amount, Mehlich-1 extractor volume and stirring time, the validation of the newly developed method was performed by evaluating the following parameters: matrix adjustment, linearity, linear range, limits of detection (LOD) and of quantification (LOQ), precision and accuracy. The analytical method proposed by this study can be routinely employed for the evaluation of soil toxicity since it presented advantages such as simplicity, speed and efficacy, as well as being precise and accurate.

É altamente desejável desenvolver testes analíticos com resultados de elevada qualidade e reduzir o tempo que é utilizado para esta finalidade. Neste contexto, um novo método de metilação de ácidos graxos assistido por ultra-som, rápido e eficiente para obtenção de ésteres com melhor qualidade para análise de alimentos, foi otimizado e validado através da aplicação da metodologia de superfície de resposta, sendo obtido um tempo de esterificação ideal de 11,72 min, 71% mais rápido do que o melhor método, que é comumente utilizado para esta finalidade. O novo processo de metanólise pode ser eficazmente aplicado a amostras com ácidos graxos livres e os teores de umidade superior a 10 e 5%, respectivamente, sem o risco de oxidação de compostos durante o processo.

Actually, it is highly desirable to develop analytical assays with high quality results, while reducing the amount of time which is used for this finality. In this context, a new, fast and efficient ultrasound-assisted fatty acid methylation method, specially focused to obtain esters with better quality for food analysis, was optimized and validated through the application of response surface methodology, and an optimum esterification time of 11.72 min was achieved, 71% faster than the best method which is commonly used for this purpose. The new methanolysis procedure can be effectively applied to samples with free fatty acid and moisture contents up to 10 and 5% m/v, respectively, without risks of compound oxidation during the process.

O perfil de ácidos graxos (AG) é um parâmetro importante de qualidade e tipificação para alimentos em geral. Esses perfis funcionam como uma espécie de "impressão digital", e podem ser úteis para monitorar fraudes e deterioração em diversos tipos de alimentos. Para os óleos vegetais, o perfil de AG é geralmente determinado após hidrólise, metilação e análise por cromatografia gasosa (CG). Neste trabalho, a metilação do óleo de soja por métodos de catálise básica e ácida foi monitorada por CG-DIC e também por espectrometria de massas ambiente com ionização sonic-spray (EASI-MS). Os principais parâmetros monitorados por EASI-MS foram o perfil de AG e a possível geração de hidroperóxidos dos ésteres metílicos, que foram comparados. O método catalisado por base mostrou-se superior em relação aos demais, por ser mais barato, menos tóxico, não originar produtos de oxidação e ter maior rendimento (95,66% m/m contra 92,86% e 94,51% dos métodos catalisados por ácido).

The fatty acids (FA) profile is an important parameter for quality control and typification for foods in general. These profiles work as a sort of "fingerprint", and may be useful to monitor frauds and deterioration of diverse types of foods. For vegetable oils, the FA profile is commonly determined after hydrolysis, methylation and gas chromatography (GC) analysis. In this work, the acid and base-catalyzed soybean oil methylation methods was monitored via GC-FID and also by ambient sonic-spray ionization mass spectrometry (EASI-MS). The base-catalyzed method is much superior regarding other esterification assays, because it is cheaper, less toxic, no oxidation products are formed and its reaction yield is greater (95.66% m/m against 92.86% and 94.51% from acid-catalyzed methylation methods, respectively).

As capacidades antioxidante de sete frutas nativas e exóticas do Brasil foram avaliadas usando os métodos DPPH•, ABTS•+ e FRAP, além da determinação do conteúdo de fenólicos totais e composição de ácidos graxos. Murici e dovialis apresentaram os maiores conteúdos de compostos fenólicos (243,42 e 205,98 mg EAG 100 g-1, respectivamente), e maiores capacidades antioxidante pelo método de FRAP (24,97 e 23,70 µmol Fe2+ g-1, respectivamente). Pelos métodos de DPPH• e ABTS•+, dovialis apresentou a maior capacidade antioxidante, 9,59 e 10,41 ET g-1, respectivamente. Os maiores teores dos ácidos alfa-linolênico e linoleico foram encontrados na siriguela (107,86 mg AG g-1 LT) e tomatinho do mato (215,50 mg AG g-1 LT), respectivamente. A análise de componentes principais (PCA) dos ácidos graxos gerou três significantes PCs, que representaram 99,75% do conjunto de dados da variância. Os dados de PCA das análises de antioxidantes geraram dois significantes PCs, representando 97,00% do total de variância.

The antioxidant capacities of seven exotic and native fruits from Brazil were evaluated using DPPH•, ABTS•+ and FRAP assays, in addition to their total phenolic content and fatty acid composition. Murici and dovialis presented the highest total phenolic contents (243.42 and 205.98 mg GAE 100 g-1, respectively), and the highest antioxidant capacities by the FRAP assay (24.97 and 23.70 µmol Fe2+ g-1, respectively). In the DPPH• and ABTS•+ assays, dovialis presented the highest antioxidant capacity, 9.59 and 10.41 TE g-1, respectively. The highest alpha-linolenic and linoleic acid contents were found in siriguela (107.86 mg FA g-1 TL) and tomatinho do mato (215.50 mg FA g-1 TL), respectively. The principal component analysis (PCA) of fatty acids yielded three significant PCs, which accounted for 99.75% of the data set total variance. The PCA data of the antioxidant analyses yielded two significant PCs, which accounted for 97.00% of the total variance.

A aceitação de tratamentos enriquecidos com óleo de tungue e a incorporação do ácido linolênico conjugado (CLnA) em filés de tilápia melhorada geneticamente (GIFT) foram investigadas. A dieta teve boa aceitação e, após 10 dias, o ClnA havia sido incorporado nos filés, mostrando um teor de 1,02% dos ácidos graxos totais (AG). Além disso, a biossíntese dos isômeros do ácido linoleico conjugado - CLA (0,31% de teor de AG total no filé), a partir do CLnA, e a presença do ácido alfalinolênico - LNA (1,08% de teor de AG total no filé), ácido eicosapentaenoico - EPA (2,85 % de teor de AG total no filé) e ácido docosa-hexaenoico - DHA (3,08% de teor de AG total no filé) foram observados. Assim, o consumo deste peixe pode aumentar a ingestão de diferentes AG (CLnA, CLA, LNA, EPA e DHA), que desempenham um papel importante no metabolismo humano.

The acceptance of tung oil enriched diet and the incorporation of conjugated linolenic acid - CLnA into fillets of Genetically Improved Farmed Tilapia (GIFT) were investigated. The diet was well accepted, and after 10 days CLnA was incorporated into the fillets with a 1.02% content of total fatty acids (FA). In addition, biosynthesis of the conjugated linoleic acid isomers - CLA (0.31% of fillet total FA content) from CLnA, and the presence of alpha-linolenic acid - LNA (1.08% of fillet total FA content), eicosapentaenoic acid - EPA (2.85% of fillet total FA content) and docosahexaenoic acid - DHA (3.08% of fillet total FA content) were observed. Therefore, the consumption of this fish can increase the intake of different FA (CLnA, CLA, LNA, EPA and DHA), which play an important role in human metabolism.

Conduziu-se este estudo, com o objetivo de quantificar o ácido alfa-linolênico (LNA, 18:3n-3) em folhas de trigo secas e colhidas em diferentes estádios de desenvolvimento (20, 40 e 80 dias), determinar o potencial antioxidante e o conteúdo de fenólicos totais em folhas colhidas aos 80 dias, assim como realizar a analise de minerais (Na, K, Fe, Ca, Mg, P, Zn, Cu e Mn). Foi verificada uma predominância de ácidos graxos poli-insaturados (AGPI) comparado com os ácidos graxos saturados (AGS) na fração lipídica das folhas. As folhas colhidas em todos os períodos apresentaram razões de AGPI/AGS e de ácidos graxos ômega-6 e ômega-3 (n-6/n-3), dentro dos valores considerados adequados para a alimentação. O maior teor de LNA foi encontrado nas folhas colhidas aos 60 dias, correspondendo a 2.146,72 mg 100 g-1 de matéria seca. Entre 60 e 80 dias, observou-se uma queda de cerca de 30% na concentração de LNA. A fração acetato foi eficiente na inibição do radical DPPH, apresentando valor de IC50 de 154 µg mL-1, e o teor de compostos fenólicos foi de 615,4 ± 36,4 mg EAG L-1, ambas as análises para as folhas colhidas aos 80 dias. Nesse estádio de crescimento, as folhas apresentaram consideráveis teores dos minerais P, Zn, Cu e Mn. Tais resultados reforçam a importância do uso de folhas de trigo para alimentação humana, em função de seu potencial antioxidante e consideráveis teores de LNA.

The objective of this study was to quantify alpha-linolenic acid (LNA, 18:3n-3) of dried wheat leaves, harvested at different development stages (20, 40 and 80 days), to determine the antioxidant potential and the total phenolic compounds of leaves harvested at 80 days, as well as to perform mineral analysis (Na, K, Fe, Ca, Mg, P, Zn, Cu and Mn). It was observed a predominance of polyunsaturated fatty acids (PUFA) compared to saturated fatty acids (SFA) in the lipid fraction of leaves. Leaves collected in all periods presented ratios of PUFA/SFA, omega-6 and omega-3 fatty acids (n-6/n-3) considered suitable for food. The highest content of LNA was found in leaves harvested at 60 days, corresponding to 2.146,72 mg 100 g-1 dried matter. The range time between 60 and 80 days showed a decline of nearly 30% in the concentration of LNA. The acetate fraction was the most effective over DPPH radical assay, showing IC50 value of 154 µg mL-1, and the phenolic compounds content was 615.4 ± 36.4 mg EAG L-1, both analyses carried out in leaves harvested at 80 days. In this development stage, wheat leaves showed significant levels of the minerals P, Zn, Cu and Mn. These results reinforce the potential of using wheat leaves in foods, according to its antioxidant content and significant levels of LNA.

O objetivo do presente trabalho foi avaliar os efeitos do óleo de linhaça sobre as concentrações dos teores de ácidos graxos poli-insaturados n-6 e n-3 (AGPI) em cabeças de tilápia do Nilo (Oreochromis niloticus), um resíduo do pescado normalmente descartado durante o processo de filetagem. A quantificação dos ácidos graxos poli-insaturados foi realizada utilizando-se cromatografia gasosa (CG), sendo a concentração dos ácidos graxos expressa em termos de massa absoluta através da utilização do éster metílico (23:0) como padrão interno e do TCFx (fator de correção teórica do FID). As tilápias receberam dietas com níveis crescentes de óleo de linhaça (0,00, 1,25, 2,50, 3,75 e 5,00%) em substituição ao óleo de girassol (controle) durante um período de cinco meses. A ingestão de LNA causa a dessaturação sequencial e alongamento das cadeias carbônicas de ácidos graxos presentes nas cabeças de peixes, levando a um aumento em todos os AGPIs n-3. Este experimento demonstrou claramente que a adição de óleo de linhaça na ração de tilápia do Nilo aumenta significativamente as concentrações (em 100 g-1 de cabeça) de LNA (100,8 para 973,6 mg), EPA (4,8 para 82,1 mg) e DHA (24,0 para 125,4 mg). Estas alterações contribuem acentuadamente para melhorar a razão AGPI n-6/n-3 e, desta forma, pode ser utilizada em suplementos alimentícios, transformando as cabeças de tilápia em valiosa alternativa como fonte de alimento para dieta humana.

The objective of this study was to examine the effects of linseed oil on n-6 and n-3 polyunsaturated (PUFA) fatty acid content in the heads of Nile tilapia (Oreochromis niloticus), these are normally discarded during the filleting process. The quantification of PUFA was carried out in absolute weights through the use of methyl ester (23:0), as an internal standard, and TCFx (theoretical FID correction factor) by GC gas chromatography. Tilapias were given diets with increasing levels (0.00, 1.25, 2.50, 3.75 and 5.00%) of linseed oil as a replacement for sunflower oil (control) for a period of five months. The ingestion of LNA causes sequential desaturation and elongation in fish heads, leading to an increase in all n-3 PUFAs. This experiment demonstrated clearly that adding linseed oil to the feed of Nile tilapia can markedly increase the amounts (per 100 g-1 of head) of LNA (100.8 to 973.6 mg), EPA (4.8 to 82.1 mg), and DHA (24.0 to 125.4 mg) in their heads, and thus, may be used to help balance n-6/n-3 PUFA ratios in dietary supplements, and creating a valuable alternative food source in the human diet.

The carrot leaf dehydration conditions in air circulation oven were optimized through response surface methodology (RSM) for minimizing the degradation of polyunsaturated fatty acids, particularly alpha-linolenic (LNA, 18:3n-3). The optimized leaf drying time and temperature were 43 h and 70 ºC, respectively. The fatty acids (FA) were investigated using gas chromatography equipped with a flame ionization detector and fused silica capillary column; FA were identified with standards and based on equivalent-chain-length. LNA and other FA were quantified against C21:0 internal standard. After dehydration, the amount of LNA, quantified in mg/100 g dry matter of dehydrated carrot leaves, were 984 mg.