A critical survey of predictive mathematical models for migration from packaging

The migration of chemicals from food contact materials into foods is an important issue in food safety.The assessment of materials compliance with regulations includes migration monitoring for many monomers and additives. However,it is recognized that predictive mathematical modelling can be used in many cases, to avoid or to reduce the effort on migration experiments. This article reviews the approaches followed to apply mathematical models to migration, particularly the models used, the approaches to estimate model parameters, and the systems used to experimentally validate the models. Conclusions on the issues requiring further research are drawn

Produção comparativa de etanol da cana-de-açúcar, batata inglesa e beterraba por fermentação

Introduction: The search for fuels from renewable sources is extremely important for the environment, since they have less release of toxic gases during combustion. Ethanol is an example of a renewable source fuel and can be obtained through the fermentation process of yeasts of the species Saccharomyces cerevisiae and raw materials that contain sugar such as sugar cane and beet, or starchy raw materials such as potatoes. Objective: This work aims to evaluate the production of ethanol from the fermentation of sugarcane, beet and potato potatoes and to compare the ethanol content obtained by each substrate. Methods: The fermentation was carried out in conical flasks with marcerated substrates and biological yeast, in the proportion 1:10 and in the following conditions 30º C, 8 hours, under agitation. For the potato substrate, the saccharification step was added with a 1% v / v sulfuric acid solution. Then, the samples rested at room temperature for 15 hours for the measurement of ethanol, which was carried out by a densimeter and compared the alcohol content of the three fermentation processes. Results: The data obtained showed that sugarcane had an average ethanol yield of 9.83%, followed by potatoes with an average of 1.7%, and beet with an average of 1.24%. Conclusion: Thus, the sugarcane showed the best source for the production of biotenol, both because of the higher alcohol content obtained and because of the ease of production.  Introdução: A busca por combustíveis de fontes renováveis é de extrema importância para o meio ambiente, uma vez têm menor liberação de gases tóxicos durante a combustão. O etanol é um exemplo de combustível de fonte renovável e pode ser obtido pelo processo de fermentação de leveduras da espécie Saccharomyces cerevisiae e matérias-primas que possuem açúcar como cana-de-açúcar e beterraba, ou matérias-primas amiláceas como a batata. Objetivo: TEste trabalho tem por objetivo avaliar a produção de etanol a partir da fermentação do caldo de cana-de-açúcar, beterraba e batata inglesa e comparar o teor de etanol obtido por cada substrato. Métodos: Foi realizada a fermentação em erlenmeyer com substratos marcerados e fermento biológico, na proporção 1:10 e nas seguintes condições 30º C, 8 horas, sob agitação. Para o substrato batata, foi adicionada a etapa de sacarificação com uma solução de ácido sulfúrico 1 % v/v. Em seguida, as amostras repousaram em temperatura ambiente por 15 horas para a dosagem de etanol, o qual foi realizado por densímetro e comparado o teor alcóolico dos três processos de fermentação. Resultados: Os dados obtidos demonstraram que a cana-deaçúcar apresentou uma média de rendimento em etanol de 9,83%, seguido da batata com uma média de 1,7%, e a beterraba com média de 1,24%. Conclusão: Desta forma, a cana-de-açúcar mostrou melhor fonte para produção de biotenol, tanto pelo maior teor alcóolico obtido, quanto pela facilidade na produção

Pesquisa de dados bot?nicos de plantas ?teis coletadas por naturalistas europeus no s?culo XIX no norte/nordeste de Minas Gerais: dados bot?nicos, qu?micos e ensaios antioxidantes de Erythroxylum suberosum A. St.-Hil (Erythroxylaceae)

No s?culo XIX o Brasil foi visitado por naturalistas europeus, atra?dos pelas riquezas naturais do pa?s. O franc?s Saint-Hilaire, em sua obra Plantas Usuais dos Brasileiros descreveu plantas que eram usadas pelos habitantes da regi?o norte/nordeste de Minas Gerais. Dentre estas, encontra-se a Erythroxylum suberosum A. St.-Hil. (Erythroxylaceae), conhecida popularmente como ?galinha-choca? e ?merc?rio do campo?, abundante nas proximidades da cidade de Diamantina (MG). Os objetivos do presente trabalho foram o resgate de informa??es sobre as esp?cies bot?nicas descritas por Saint-Hilaire no norte/nordeste de Minas Gerais, no s?culo XIX, inclu?das em sua obra Plantas usuais dos brasileiros e a realiza??o de estudo fitoqu?mico e determina??o da atividade antioxidante de extratos das folhas de E. suberosum. Foram realizadas pesquisas em herb?rios virtuais para detec??o de coletas, nos s?culos XIX, XX e XXI, de quinze esp?cies descritas por Saint-Hilaire no norte/nordeste de Minas Gerais, em sua obra. Estas informa??es foram usadas no direcionamento de coletas destas esp?cies na regi?o de Diamantina e na verifica??o da ocorr?ncia atual de tais plantas. Algumas esp?cies s?o encontradas, ainda na atualidade, nos locais citados pelo naturalista ou em localidades muito pr?ximas: quatro, das quinze esp?cies encontradas por Saint-Hilaire, foram coletadas e georreferenciadas nas proximidades de Diamantina. Para realiza??o de estudo fitoqu?mico e determina??o de atividade antioxidante, as folhas de E. suberosum foram coletas em Diamantina-MG. O material, seco e pulverizado, foi usado para macera??o com os solventes hexano, acetato de etila e etanol e extra??o pelo M?todo Stas-Otto, para pesquisa de alcaloides. A triagem fitoqu?mica dos extratos sugeriu a presen?a de alcal?ides, cumarinas, flavonoides (incluindo antocianidinas), taninos condensados e triterpenos/esteroides e an?lises por CLAE/DAD sugeriram a presen?a de compostos fen?licos nas amostras. Os extratos preparados pelo M?todo Stas-Otto foram analisados por CG/EM, sendo sugerida a presen?a de 23 subst?ncias, dentre as quais encontrase o alcaloide trop?nico tropacoca?na. Quanto ? atividade antioxidante os extratos de E. suberosum, quando comparados ao padr?o (?cido g?lico), n?o apresentaram pronunciada atividade de retirada de radical DPPH; no entanto, o extrato etan?lico apresentou uma maior quantidade de fen?licos totais, maior poder de redu??o do ?on met?lico Fe3+ e maior capacidade antioxidante pela an?lise por voltametria c?clica. Assim este trabalho contribuiu para a recupera??o e disponibiliza??o de informa??es sobre plantas ?teis coletadas por naturalistas europeus no norte/nordeste de Minas Gerais e para o conhecimento sobre a composi??o qu?mica e atividade antioxidante da esp?cie E. suberosum.Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (Capes)Disserta??o (Mestrado) ? Programa de P?s-gradua??o em Ci?ncias Farmac?uticas, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2014.ABSTRACT In 19th century the Brazil was visited by European naturalists, attracted by the country's natural resources. The French Saint-Hilaire, in his book Useful Brazilian plants described plants that were used by the residents of the north /northeast region of Minas Gerais. Among these is Erythroxylum suberosum A. St.-Hil. (Erythroxylaceae), popularly known as "galinha choca" and "merc?rio do campo" abundant near the city of Diamantina ( MG ). The objectives of this study were the rescue of the information about botanical species described by Saint- Hilaire in the north/northeast of Minas Gerais, in the 19th century, included in his Useful Brazilian plants and realization of phytochemical study and determination of the activity antioxidant of the extracts of the leaves of E. suberosum. Researches were conducted in virtual herbarium for detection of collections in 19th, 20th and 21th centuries of fifteen species described by Saint-Hilaire in the north/northeast of Minas Gerais, in his book. This information was used in targeting these species collected in the region of Diamantina and verify the actual occurrence of this plants. Some species are found, even today, in the places cited by the naturalist or very nearby localities. Four species found near Diamantina were collected and georeferenced. To perform phytochemical study and determination of antioxidant activity, the leaves of E. suberosum were collected in Diamantina-MG. The material, dried and pulverized, was used for maceration with the solvents hexane, ethyl acetate and ethanol and extraction by Stas-Otto method, for the detection of alkaloids. The phytochemical screening of the extracts suggested the presence of alkaloids, coumarins, flavonoids (including anthocyanins), condensed tannins and triterpenes/steroids. The extracts prepared by Stas-Otto method were analyzed by GC/MS, being suggested the presence of 23 substances, among which is the tropane alkaloid tropacocaine. As for antioxidant activity the extracts of E. suberosum, when compared to standard (galic acid), showed no pronounced activity withdrawing DPPH radical; however, the ethanolic extract showed a higher content of phenolic compounds and greater power reduction of Fe3+ metal ion and greater antioxidant potential in assay performed by cyclic voltammetry. Thus this work contributed to the recovery and availability of information on useful plants collected by European naturalists in the north /northeast of Minas Gerais and the knowledge of the chemical composition and antioxidant activity of the species E. suberosum

In vitro inhibition of linoleic acid peroxidation by primary S-nitrosothiols

Nitric oxide ( NO) is an effective chain-breaking antioxidant in the inhibition of lipid peroxidation and circulates in vivo mainly as primary S-nitrosothiols (RSNOs). In this work, the in vitro peroxidation of linoleic acid-SDS comicelles (LA-SDS) catalyzed by soybean lipoxygenase (SLO) and FeII ions was monitored in the presence and absence of three primary RSNOs: S-nitrosocysteine, S-nitroso-N-acetylcysteyne and S-nitrosoglutathione. Kinetic measurements based on the formation of conjugated double bonds and fluorescent oxidized LA-lysine adducts, showed that RSNOs are more potent antioxidants than their corresponding free thiols (RSHs) in equimolar conditions. These results are consistent with the blocking of LA-SDS peroxidation by RSNOs through the inactivation of peroxyl/alkoxyl (LOO /LO ) radicals, leading to nitrogen-containing products of oxidized LA, which release free NO. These results indicate that endogenous RSNOs may play a major role in the blocking of lipid peroxidation in vivo, through the primary inactivation of alkoxyl/peroxyl radicals and also of preformed lipid hydroperoxides.O óxido nítrico ( NO) é um antioxidante efetivo na inibição da peroxidação lipídica e circula in vivo principalmente como S-nitrosotióis primários (RSNOs). Neste trabalho, a peroxidação in vitro de comicelas do ácido linileico-SDS (LA-SDS) catalisada por lipoxigenase de soja (SLO) e íons FeII foi monitorada na presença e na ausência de três RSNOs: S-nitrosocisteína, S-nitroso-N-acetilcisteína e S-nitrosoglutationa. Medidas cinéticas baseadas na formação de duplas ligações conjugadas e adutos fluorescentes de lisina-La oxidado mostraram que os RSNOs são antioxidantes mais potentes que seus tióis livres (RSHs) correspondentes em condições equimolares. Esses resultados são consistentes com o bloqueio da peroxidação de LA-SDS por RSNOs através da inativação dos radicais peroxila/alcoxila (LOO /LO ), levando a produtos nitrogenados do LA oxidado, os quais liberam NO. Esses resultados indicam que os RSNOs endógenos podem desempenhar um papel importante no bloqueio da peroxidação lipídica in vivo, através da inativação primária de radicais alcoxila/peroxila bem como de hidroperóxidos lipídicos pré-formados.18851895Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Synthesis of 4-amino-3,5-dicyano-arylpyrazoles : part 2 : isolation and characterization of by-products

Reaction of (dicyanomethylidene-hydrazino)benzoic acids with chloroacetonitrile, under basic conditions, gave cyanomethyl-3-(7-amino-3,5-dicyano-1H-pyrazolo[4,3-d]pyrimidin-1-yl-benzoates and para substituted cyanomethyl benzoates, in addition to the expected cyanomethyl 3-(4-amino-3,5-dicyano-1H-pyrazol-1-yl)-benzoates.Fundação para a Ciência e Tecnologia (Portugal). National Program for Scientific Re-equipment, contract REDE/1517/RMN/2005 with funds from POCI 2010 (FEDER) and FC

Heterogeneous Responses to Antioxidants in Noradrenergic Neurons of the Locus Coeruleus Indicate Differing Susceptibility to Free Radical Content

The present study investigated the effects of the antioxidants trolox and dithiothreitol (DTT) on mouse Locus coeruleus (LC) neurons. Electrophysiological measurement of action potential discharge and whole cell current responses in the presence of each antioxidant suggested that there are three neuronal subpopulations within the LC. In current clamp experiments, most neurons (55%; 6/11) did not respond to the antioxidants. The remaining neurons exhibited either hyperpolarization and decreased firing rate (27%; 3/11) or depolarization and increased firing rate (18%; 2/11). Calcium and JC-1 imaging demonstrated that these effects did not change intracellular Ca2+ concentration but may influence mitochondrial function as both antioxidant treatments modulated mitochondrial membrane potential. These suggest that the antioxidant-sensitive subpopulations of LC neurons may be more susceptible to oxidative stress (e.g., due to ATP depletion and/or overactivation of Ca2+-dependent pathways). Indeed it may be that this subpopulation of LC neurons is preferentially destroyed in neurological pathologies such as Parkinson's disease. If this is the case, there may be a protective role for antioxidant therapies

Heterogeneous Responses to Antioxidants in Noradrenergic Neurons of the Locus Coeruleus Indicate Differing Susceptibility to Free Radical Content

The present study investigated the effects of the antioxidants trolox and dithiothreitol (DTT) on mouse Locus coeruleus (LC) neurons. Electrophysiological measurement of action potential discharge and whole cell current responses in the presence of each antioxidant suggested that there are three neuronal subpopulations within the LC. In current clamp experiments, most neurons (55%; 6/11) did not respond to the antioxidants. The remaining neurons exhibited either hyperpolarization and decreased firing rate (27%; 3/11) or depolarization and increased firing rate (18%; 2/11). Calcium and JC-1 imaging demonstrated that these effects did not change intracellular Ca2+ concentration but may influence mitochondrial function as both antioxidant treatments modulated mitochondrial membrane potential. These suggest that the antioxidant-sensitive subpopulations of LC neurons may be more susceptible to oxidative stress (e.g., due to ATP depletion and/or overactivation of Ca2+-dependent pathways). Indeed it may be that this subpopulation of LC neurons is preferentially destroyed in neurological pathologies such as Parkinson's disease. If this is the case, there may be a protective role for antioxidant therapies

An approach to promote social and communication behaviors in children with autism spectrum disorders : robot based intervention

Most autistic people present some difficulties in developing social behavior, living in their own world. This study has the goal to improve the social life of children with autism with a main focus in promoting their social interaction and communication. It is necessary to call for children’s attention and enforce their collaboration, where a robot, LEGO MindStorm, behaves as a mediator/promoter of this interaction. A set of experiments designed to share objects and fulfill simple orders, by the 11 years old autistic child at the time of daily routine work and in-game with the robot, are described. The generalization of the acquired skills by the child in new contexts and environments are also tested. Results are described showing the outcomes of the experiments.Fundação para a Ciência e a Tecnologia (FCT) - R&D projecto RIPD/ADA/109407/200

Plant phenolic extracts as an effective strategy to control Staphylococcus aureus, the dairy industry pathogen

Staphylococcus aureus is one of the most common contagious mastitis pathogens. Bovine mastitis is considered an important reservoir for dairy industry contamination, and therefore to ensure S. aureus control has gained a pivotal importance. Natural matrices present multiple biological effects, being its antimicrobial potential increasingly reported. Thus, the present study aims to assess the antibacterial activity of several methanol:water extracts, obtained from plants, against Staphylococcus aureus. Moreover, the most effective extract was characterized in terms of phenolic compounds, by using high performance liquid chromatography coupled to diode array and mass spectrometer detectors. Among the tested extracts, Eucalyptus globulus was the most effective against all tested S. aureus strains, followed by Juglans regia and Foeniculum vulgare. Inhibition halos of the plant extracts varied between 8.0-16.0 mm, excepting for F. vulgare in which two evident halos were observed: one with growth inhibition (5.0-7.0 mm) and a second one with visible cell density reduction (13.0-14.0 mm). Susceptibility assays evidenced that E. globulus extract exerted the highest antibacterial activity (MICs=0.195-0.39 mg/mL), being effective against all the tested strains. Among the phenolic compounds identified in this extract, gallotannins, ellagic acid glycoside, and quercetin derivatives, were the most abundant; and therefore, may exert a positive and contributive effect to the observed antibacterial effect. Overall, the use of plant extracts to control bovine mastitis caused by S. aureus is a promising solution that could contribute to the reduction of the occurrence of dairy food industry contaminations, providing considerable benefits to agro-industries on the formulation of high-quality and safety dairy products.This study was supported by the Portuguese Foundation for Science and Technology (FCT) (grant number SFRH/BPD/84488/2012) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by European Regional Development Fund under the scope of Norte2020 − Programa Operacional Regional do Norte, as also Pest-OE/AGR/UI0690/2013 to CIMO. The authors are also grateful to the Interreg España-Portugal for financial support through the project 0377_Iberphenol_6_E and to Ana Maria Carvalho for the collection and identification of the wild samples, chemically characterized in previous studies.info:eu-repo/semantics/publishedVersio