82 research outputs found

    Phenolics extraction from sweet potato peels: modelling and optimization by response surface modelling and artificial neural network

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    Sweet potato peels (SPP) are a major waste generated during root processing and currently have little commercial value. Phenolics with free radical scavenging activity from SPP may represent a possible added-value product for the food industry. The aqueous extraction of phenolics from SPP was studied using a Central Composite Design with solvent to solid ratio (30-60 mL g(-1)), time (30-90 min) and temperature (25-75 A degrees C) as independent variables. The comparison of response surface methodology (RSM) and artificial neural network (ANN) analysis on extraction modelling and optimising was performed. Temperature and solvent to solid ratio, alone and in interaction, presented a positive effect in TPC, ABTS and DPPH assays. Time was only significant for ABTS assay with a negative influence both as main effect and in interaction with other independent variables. RSM and ANN models predicted the same optimal extraction conditions as 60 mL g(-1) for solvent to solid ratio, 30 min for time and 75 A degrees C for temperature. The obtained responses in the optimized conditions were as follow: 11.87 +/- 0.69 mg GAE g(-1) DM for TPC, 12.91 +/- 0.42 mg TE g(-1) DM for ABTS assay and 46.35 +/- 3.08 mg TE g(-1) DM for DPPH assay. SPP presented similar optimum extraction conditions and phenolic content than peels of potato, tea fruit and bambangan. Predictive models and the optimized extraction conditions offers an opportunity for food processors to generate products with high potential health benefits

    Especificidades de um discurso

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    Livro de homenagem à professora Maria Emília Ricardo Marque

    Chemical composition, antioxidant and alpha-Glucosidase-Inhibiting activities of the aqueous and hydroethanolic extracts of Vaccinium myrtillus Leaves

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    Vaccinium myrtillus (bilberry) leaf is traditionally used in southeastern Europe for the treatment of diabetes. In the present study, the ability of bilberry leaf extracts to inhibit carbohydrate-hydrolyzing enzymes and restore glutathione concentration in Hep G2 cells subjected to glucose-induced oxidative stress was investigated. A comprehensive analysis of the antioxidant activity of two bilberry leaf extracts was performed. The aqueous extract showed excellent total antioxidant and chelating activity. Its antioxidant activity in the beta-carotene-linoleic acid assay was very good, reaching the activity of the antioxidant standard BHA (93.4 +/- 2.3% vs. 95.1 +/- 2.4%, respectively). The hydroethanolic extract (ethanol/H2O, 8:2, v/v), on the other hand, was a better radical scavenger and Fe2+ reducing agent. Furthermore, the aqueous extract was able to efficiently increase glutathione concentration in Hep G2 cells subjected to glucose-induced oxidative stress and restore it to the levels observed in non-hyperglycaemic cells. The hydroethanolic extract strongly inhibited alpha-glucosidase, with the IC50 statistically equal to the antidiabetic drug acarbose (0.29 +/- 0.02 mg/mL vs. 0.50 +/- 0.01 mg/mL, respectively). Phytochemical analysis revealed the presence of quercetin and kaemferol derivatives, as well as chlorogenic and p-coumaric acid. The study results indicate that V. myrtillus leaf may have promising properties as a supporting therapy for diabetes.University of Zagrebinfo:eu-repo/semantics/publishedVersio

    Food composition databases: does it matter to human health?

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    Food provides humans with more than just energy and nutrients, addressing both vital needs and pleasure. Food habits are determined by a wide range of factors, from sensorial stimuli to beliefs and, once commanded by local and seasonal availability, are nowadays driven by marketing campaigns promoting unhealthy and non-sustainable foodstuffs. Top-down and bottom-up changes are transforming food systems, driven by policies on SDGs and by consumer’s concerns about environmental and health impacts. Food quality, in terms of taste, safety, and nutritional value, is determined by its composition, described in food composition databases (FDBs). FDBs are then useful resources to agronomists, food and mechanical engineers, nutritionists, marketers, and others in their efforts to address at maximum human nutrient needs. In this work, we analyse some relevant food composition databases (viz., purpose, type of data, ease of access, regularity of updates), inspecting information on the health and environmental nexus, such as food origin, production mode as well as nutritional quality. The usefulness and limitations of food databases are discussed regarding what concerns sustainable diets, the food ‘matrix effect’, missing compounds, safe processing, and in guiding innovation in foods, as well as in shaping consumers’ perceptions and food choices.info:eu-repo/semantics/publishedVersio

    Screening of the aerodynamic and biophysical properties of barley malt

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    An understanding of the aerodynamic and biophysical properties of barley malt is necessary for the appropriate design of equipment for the handling, shipping, dehydration, grading, sorting and warehousing of this strategic crop. Malting is a complex biotechnological process that includes steeping; ger-mination and finally, the dehydration of cereal grains under controlled temperature and humidity conditions. In this investigation, the biophysical properties of barley malt were predicted using two models of artificial neural networks as well as response surface methodology. Stepping time and germination time were selected as the independent variables and 1 000 kernel weight, kernel density and terminal velocity were selected as the depen-dent variables (responses). The obtained outcomes showed that the artificial neural network model, with a logarithmic sigmoid activation function, presents more precise results than the response surface model in the prediction of the aerodynamic and biophysical properties of produced barley malt. This model presented the best result with 8 nodes in the hidden layer and significant correlation coefficient values of 0.783, 0.767 and 0.991 were obtained for responses one thousand kernel weight, kernel density, and terminal velocity, respectively. The outcomes indicated that this novel technique could be successfully applied in quantitative and qualitative monitoring within the malting process

    Chemical composition, antioxidant, and α-Glucosidase-Inhibiting activity of aqueous and hydroethanolic extracts of traditional antidiabetics from croatian ethnomedicine

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    Type 2 diabetes (T2D) is a chronic disease with a growing prevalence worldwide. In addition to the conventional therapy, many T2D patients use phytotherapeutic preparations. In the present study, chemical composition, antioxidant, and -glucosidase inhibiting activity of traditional antidiabetics from Croatian ethnomedicine (Achillea millefolium, Artemisia absinthium, Centaurium erythraea, Morus alba, Phaseolus vulgaris, Sambucus nigra, and Salvia officinalis) were assessed. The efficacy of water and 80% ethanol as extraction solvents for bioactive constituents was compared. HPLC analysis revealed that the prepared extracts were rich in phenols, especially rutin, ferulic, and chlorogenic acid. Antiradical (against DPPH and ABTS radicals), reducing (towards Mo6+ and Fe3+ ions), and enzyme inhibiting properties were in linear correlation with the content of phenolic constituents. Ethanolic extracts, richer in phenolic substances, showed dominant efficacy in those assays. Aqueous extracts, on the other hand, were better Fe2+ ion chelators and more active in the -carotene linoleic acid assay. Extracts from S. officinalis and A. millefolium were particularly active antioxidants and -glucosidase inhibitors. A. absinthium, another potent -glucosidase inhibitor, contained chromium, a mineral that promotes insulin action. The investigated plants contained significant amounts of minerals useful in management of T2D, with negligible amounts of heavy metals deeming them safe for human use.IP-2018-01-6504info:eu-repo/semantics/publishedVersio

    Efficiency of triple emitter source (TES) for irrigation experiments of horticultural crops

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    Triple emitter source TES experimental irrigation was designed. Three trickle laterals were connected together in order to form a triple joint lateral. Two of them and their emitters are connected to two tanks of stock solutions. The third lateral contains only fresh water. The emitters of the two solution lines have different and varying discharges to obtain several mixings of the two stock solutions. The third line is necessary to obtain constant water application rates for each trickling point along the lateral. This method was tested for several experiments involving the study of the combined effects of salinity and fertilizers on the yield function of horticultural crops, namely lettuce and cabbage. As concluding remarks, it was shown the high uniformity of the factor to be evaluated, through the use of Christiansen coefficient of uniformity distribution CUC, which value was always larger than 90%. Main advantage of this experimental design is its smaller experimental plots (reducing pollution and research costs)

    Determination of essential minerals and trace elements in edible sprouts from different botanical families—application of chemometric analysis

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    Background: elemental deficiency may result in the malfunctioning of human organisms. Sprouts, with their attractive looks and well-established popularity, may be considered as alternative sources of elements in the diet. Moreover, the uptake of micro- and macronutrients from sprouts is better when compared to other vegetable sources. The aim of the study was to determine and compare the level of the selected essential minerals and trace elements in 25 sprouts from different botanical families, to preselect the richest species of high importance for human diets. Methods: the Cu, Zn, Mn, Fe, Mg, Ca determinations were performed using atomic absorption spectrometry with flame atomization and iodine by the colorimetric method. Results: beetroot sprouts had the highest levels of Zn, Fe, and Mg, while onion sprouts were the richest in Mn and Ca, among all of the tested sprouts. Sprouts of the Brassicaceae family were generally richer in Ca, Mg, and Zn than sprouts from the Fabaceae family. Results allow preselection of the most perspective sprouts as possible dietary sources of essential minerals and trace elements. For rucola, leeks, onions, and beetroot sprouts, the data on minerals and trace element compositions were performed for the first time.info:eu-repo/semantics/publishedVersio

    Alta prevalência e associação do subtipo não-B do vírus HIV-1 com risco específico de transmissão sexual entre pacientes virgens de tratamento antirretroviral em Porto Alegre, Brasil

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    In South Brazil the circulation of two HIV-1 subtypes with different characteristics represents an important scenario for the study of the impact of HIV-1 diversity on the evolution of the HIV-1 epidemic and AIDS disease. HIV-1 B, the predominant variant in industrialized countries and HIV-1 C, the most prevalent subtype in areas with rapid epidemic growth, are implicated in most infections. We evaluated blood samples from 128 antiretroviral (ARV) naïve patients recruited at entry to the largest HIV outpatient service in Porto Alegre. Based on partial pol region sequencing, HIV-1 C was observed in 29%, HIV-1 B in 22.6% and, the recently identified CRF31_BC, in 23.4% of 128 volunteers. Other variants were HIV-1 F in 10% and other mosaics in 5.5%. In order to evaluate the association of socio-behavioral characteristics and HIV-1 subtypes, interviews and laboratory evaluation were performed at entry. Our data suggest an established epidemic of the three major variants, without any evidence of partitioning in either of the subgroups analyzed. However, anal sex practices were associated with subtype B, which could indicate a greater transmissibility of non-B variants by vaginal intercourse. This study provides baseline information for epidemiologic surveillance of the changes of the molecular characteristics of HIV-1 epidemics in this region.No sul do Brasil a circulação de dois subtipos de HIV-1 com características diferentes representa importante cenário para o estudo do impacto da diversidade do HIV-1 na evolução da epidemia e na AIDS. O HIV-1 B, variante predominante nos países industrializados e o HIV-1 C, o subtipo mais prevalente em áreas com maiores taxas de crescimento da epidemia, estão implicados na maioria das infecções. Avaliamos amostras de sangue de 128 pacientes sem exposição a antirretrovirais, recrutados ao ingressarem no maior serviço ambulatorial de HIV/AIDS de Porto Alegre. Com base no sequenciamento parcial da região pol, o HIV-1 C foi observado em 29%, HIV-1 B em 22,6% e uma forma recombinante recentemente descrita, CRF31_BC, foi observada em 23,4% entre 128 voluntários. Outras variantes encontradas foram HIV-1 F em 10% e outros mosaicos em 5,5%. Para avaliar associações entre características sócio-comportamentais e subtipos do HIV-1 foram realizadas entrevistas e exames laboratoriais na entrada do estudo. Nossos dados sugerem uma epidemia estabelecida dessas três variantes principais, sem evidência de compartilhamento em nenhum subgrupo analisado. Entretanto, prática sexual anal se mostrou associada à transmissão de subtipo B, o que pode indicar maior transmissibilidade das variantes não-B por intercurso vaginal. Este estudo permite delinear uma linha de base para o monitoramento epidemiológico das mudanças nas características moleculares da epidemia do HIV-1 nesta região

    Investigation of oral and general health status and IL-1β gene polymorphism as risk factors for oral mucositis in hematopoietic stem cell transplantation patients

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    The aim of the present study was to analyze the relationship of OM with possible risk factors such as oral health condition, immunological status and IL-1β profile in patients submitted to hematopoietic stem cell transplantation (HSCT). Fifty-four individuals submitted to HSCT were included. All patients received previous dental treatment and photobiomodulation (PBM) as the institutional OM preventive protocol. OM scores, immune status, and IL-1β levels were determined during the conditioning period and at D+3 and D+8 after HSC infusion. IL-1β gene polymorphism was also analyzed during conditioning. Possible associations of OM with risk factors were analyzed using conditional Fisher’s exact test. OM was observed in 34 patients (62.9%) classified as Grade 1 (13 patients/24.1%), Grade 2 (14 patients/25.9%), Grade 3 (3 patients/5.5%), and Grade 4 (4 patients/7.4%). Allogeneic HSCT individuals exhibited a higher OM grade than autologous subjects. Moreover, an association was observed between severe OM and severe gingivitis (p = 0.01), neutropenia (p = 0.03), and leukopenia (p = 0.04). A significant association between OM and lower IL-1β levels was detected at three time points, i.e., conditioning (p = 0.048), D+3 (p = 0.01), and D+8 (p = 0.005). The results showed that IL-1β gene polymorphism was not associated with OM. Our study provided important insights into the scope of OM risk factors in the setting of HSCT. Patients submitted to HSCT with severe gingivitis prior to chemotherapy and with severe neutropenia and leukopenia exhibited a higher OM grade. Further investigation will be necessary to better understand the exact role of IL-1β in the context of OM pathobiology and to validate cytokine analysis in larger cohorts
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