140 research outputs found

    Avaliação da eficiência de diferentes produtos enológicos na remoção de ocratoxina A de vinho

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    As micotoxinas são metabolitos secundários tóxicos produzidos por certos fungos, sendo a ocratoxina A (OTA) das mais importantes. A presença de OTA nos vinhos pode constituir um risco para a saúde dos consumidores, sendo por isso aconselhado que se tomem medidas para atingir níveis seguros para o consumo humano [1]. De acordo com o Regulamento n.º 1881/2006 da Comissão Europeia, o limite máximo para a OTA em vinho é de 2 µg/kg [2]. Sendo assim, foi objetivo deste trabalho conhecer a eficiência de diferentes produtos enológicos na remoção de OTA de vinhos, bem como o seu impacto nas suas características organoléticas. Foram testados onze produtos enológicos diferentes, com origem mineral, sintética, microbiana, vegetal e animal, de forma a avaliar a sua eficiência na remoção de OTA de vinhos. Os ensaios foram realizados em vinhos artificialmente suplementados com OTA numa concentração final de 10 µg/L. O produto enológico mais eficiente na remoção de OTA do vinho branco (80%) é composto por gelatina, bentonite e carvão ativado. Reduções entre 10-30% foram também obtidas com o caseinato de potássio, paredes de células de levedura e proteína de ervilha. Com a aplicação de bentonite, carboximetilcelulose, polivinilpolipirrolidona e quitosana não se verificou nenhuma remoção considerável de OTA dos vinhos brancos. Estes resultados podem fornecer informações úteis para os produtores de vinho, ajudando-os na seleção do produto enológico mais adequado para a remoção de OTA de vinhos brancos, reduzindo a toxicidade do vinho e melhorando simultaneamente a segurança alimentar e qualidade do produto final.Agradecimentos: Este trabalho foi financiado por fundos FEDER através do Programa Operacional Factores de Competitividade - COMPETE e por fundos nacionais através da Fundação para a Ciência e a Tecnologia -FCT, ref. FCOMP-01-0124-FEDER-028029 e PTDC/AGR-TEC/3900/2012, respetivamente. Luís Abrunhosa recebeu apoio através da bolsa Incentivo/EQB/LA0023/2014 do ON.2 O Novo Norte

    Uso de Pediococcus parvulus para a degradação e destoxificação biológica de ocratoxina A, respetivo método e kit

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    National Patent (INPI)A presente invenção refere-se ao uso de um microrganismo para a degradação e destoxificação biológica de micotoxinas, mais especificamente para a degradação da ocratoxina A em ocratoxina a. Concretamente, relaciona-se com o uso de Pediococcus parvulus para a destoxificação de alimentos e rações. Outro aspeto da presente invenção relaciona-se com o método de destoxificação e a sua aplicação a um kit. A invenção insere-se na área farmacêutica, alimentar e veterinária.info:eu-repo/semantics/publishedVersio

    New synthetic compounds as inhibitors of mycotoxin synthesis

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    Ochratoxin A (OTA) is a mycotoxin produced by some Aspergillus and Penicillium species which is often detected in beer, cereals, coffee, feeds, figs, sultanas and wine. Some fungicides have been found to be effective in preventing fungal growth, but, in other cases, an increase in the synthesis of mycotoxins was reported. Also, the pressure to use less harmful compounds to the environment stimulates the exploration of new and more benign compounds. Synthetic compounds were tested on the growth and OTA production of one strain of A. alliaceus, A. ochraceus, A. carbonarius and A. niger. These new synthetic compounds have a linear structure incorporating urea and/or a phenolic unit. Fungi were grown in yeast extract sucrose (YES) medium supplemented with 50 μM to 200 μM of each one of 20 test compounds in triplicate, for 6 days. Growth was recorded by measuring the diameter of colonies every 24 hours, and OTA was quantified after 5 days of growth using HPLC and fluorescence detection. Growth of the A. ochraceus and the A. carbonarius strains were not inhibited by most of these compounds. However, some led to a decrease in OTA detection. Compounds without the phenolic unit were found to be less effective, while those compounds with urea and phenolic units were the most effective. Growth of the A. alliaceus and of the A. niger strains were inhibited by compound-X by 22 and 27% respectively. This approach will lead to the selection of functional groups able to inhibit the synthesis of OTA which could be incorporated into more powerful antifungal compounds.Fundação para a Ciência e a Tecnologia (FCT) - SFRH/BD/11228/2002, SFRH/BD/3185/2000, SFRH/BPD/12044/2003

    The condensation of salicylaldehydes and malononitrile revisited : synthesis of new dimeric chromene derivatives

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    The reaction of salicylic aldehydes with malononitrile was reinvestigated, and the reaction pathway was followed by 1H NMR spectroscopy. A delicate control of the experimental conditions allowed the synthesis of 2-imino-2H-chromene-3-carbonitriles 1, (2-amino-3-cyano-4H-chromen-4-yl)malononitriles 2, 4-amino-5-imino-2,7-dimethoxy-5H-chromeno[3,4-c]pyridine-1-carbonitrile 12, and (4,5-diamino-1-cyano-1,10b-dihydro-2H-chromeno[3,4-c]pyridin-2-ylidene)malononitrile 13. Two novel 2-iminochromene dimers, with structures 8 and 9, were isolated and fully characterized. The activity of compound 8a on Aspergillus spp. growth and on ochratoxin A production was evaluated. The results of the bioassays indicate that compound 8a, applied at concentrations of 2 mM, totally inhibited the growth of the fungi tested. Ochratoxin A production by Aspergillus alliaceus was reduced by about 93% with a 200 μM solution of this compound. A moderate inhibitory effect was observed for the analogous structure 8b, and no inhibition was registered for compounds 2 and 1, used as synthetic precursors of the dimeric species 8

    Effects of moderate electric fields on the post-harvest preservation of chestnuts

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    Ohmic heating (OH) was evaluated as a post-harvest technology to improve chestnuts shelf-life (Castanea sativa Mill.) by controlling molds and insect larvae proliferation. Chestnuts were processed by OH at 35, 45, and 55 °C and compared with untreated fruits and the conventional hydrothermal technology (HT - 50 °C for 45 min), which is the process currently used by the chestnut industry. Shelf-life studies were carried out at different atmospheric conditions for 60 days: (i) 25 °C and 40% relative humidity (RH); (ii) 5 °C and 70% RH. The results show that the OH conducted at 55 °C (OH-55 °C), combined with storage at 5 °C, was more effective in controlling molds and larvae growth than the other treatments. Moreover, under these conditions, chestnuts shelf-life could be extended for 60 days without substantial changes in the fruits color and texture. After the OH-55 °C treatment, lower losses of some nutrients and vitamin C were registered compared to HT. This study demonstrates for the first time that OH has the potential to be used by the chestnut industry for the post-harvest disinfestation of this fruit.This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2020 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. Enrique Pino-Hernández is a recipient of a fellowship supported by an advanced doctoral training program (call NORTE-69-2015-15), funded by the European Social Fund under the scope of Norte2020 – Programa Operacional Regional do Norte (NORTE-08-5369-FSE 000036). Ricardo N. Pereira and Luís Abrunhosa acknowledge FCT for their Assistant Research contract obtained under CEEC Individual 2017: reference CEECIND/02903/2017 and CEECIND/00728/2017, respectively.info:eu-repo/semantics/publishedVersio

    Chemoradiotherapy completion and neutropenia risk in HIV patients with cervical cancer

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    Copyright © 2018 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.This is an open access article distributed under the Creative Commons Attribution License 4.0 (CCBY), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. http://creativecommons.org/licenses/by/4.0Cervical cancer (CC) is one of the acquired immunodeficiency syndrome (AIDS) defining diseases and the human immunodeficiency virus (HIV) infection is thought to relate with increased acute toxicity of chemoradiotherapy (CRT). We investigated the effect of HIV status in the incidence of neutropenia associated with cisplatin-based CRT for CC and its impact in treatment completion. This is a single-center retrospective cohort study. Data collection was performed for all the consecutive stage Ib-IV CC women treated with cisplatin-based CRT from 2012 to 2016, and with known HIV status. Sixty-one patients were included, 6 were HIV+. HIV+ patients had a higher risk of neutropenia at any cycle during cisplatin CRT [adjusted odds ratio (OR) 7.3, 95% confidence interval (95% CI) 1.02–52.3; P = .05]. Despite the absolute differences, mean neutrophil count was nonsignificantly lower in HIV+ women, both at baseline [4455/μL (interquartile range, IQR: 1830–6689) vs 6340 (IQR: 1720–18,970) for HIV−, P = .98] and at the end of treatment [1752/μL (IQR: 1100–2930) vs 3147/μL (IQR: 920–18,390) in HIV−; P = .06]. Moreover, when considering the effect of time, CRT seems to induce a consistent drop of neutrophils in both groups (P = .229). No febrile neutropenia events occurred. In HIV+ women, there were more CT cycle delays (P = .013), patients were more prone to use granulocyte colony-stimulating factor (G-CSF; HIV+ 40.0% vs HIV− 4.0%; P = .04) and less likely to complete at least 5 cycles of cisplatin (P = .02). All patients received adequate dose of pelvic RT, regardless of HIV status. HIV+ patients have a significantly increased risk of neutropenia during CRT treatment for CC and are less likely to complete chemotherapy with cisplatin.info:eu-repo/semantics/publishedVersio

    Callous-unemotional traits moderate anticipated guilt and wrongness judgments to everyday moral transgressions in adolescents

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    The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fpsyt.2021.625328/full#supplementary-materialCallous-unemotional (CU) traits observed during childhood and adolescence are thought to be precursors of psychopathic traits in adulthood. Adults with high levels of psychopathic traits typically present antisocial behavior. Such behavior can be indicative of atypical moral processing. Evidence suggests that moral dysfunction in these individuals may stem from a disruption of affective components of moral processing rather than from an inability to compute moral judgments per se. No study to date has tested if the dissociation between affective and cognitive dimensions of moral processing linked to psychopathic traits in adulthood is also linked to CU traits during development. Here, 47 typically developing adolescents with varying levels of CU traits completed a novel, animated cartoon task depicting everyday moral transgressions and indicated how they would feel in such situations and how morally wrong the situations were. Adolescents with higher CU traits reported reduced anticipated guilt and wrongness appraisals of the transgressions. However, our key finding was a significant interaction between CU traits and anticipated guilt in predicting wrongness judgments. The strength of the association between anticipated guilt and wrongness judgement was significantly weaker for those with higher levels of CU traits. This evidence extends our knowledge on the cognitive-affective processing deficits that may underlie moral dysfunction in youth who are at heightened risk for antisocial behavior and psychopathy in adulthood. Future longitudinal research is required to elucidate whether there is an increased dissociation between different components of moral processing from adolescence to adulthood for those with high psychopathic traits.This study was supported by the Portuguese Foundation for Science and Technology (FCT) research grant awarded to AS-C (PTDC/MHC-PCN/2296/2014), co-financed by FEDER through COMPETE2020 under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-016747). The study was conducted at the Psychology Research Center (PSI/01662), School of Psychology, University of Minho, supported by FCT through the Portuguese State Budget (Ref.: UIDB/PSI/01662/2020)

    The effect of culture preservation techniques on patulin and citrinin production by Penicillium expansum Link

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    Aims: To study the influence of culture preservation methods and culture conditions on the production of the mycotoxins patulin and citrinin by Penicillium expansum. Methods and results: Ten strains of Penicillium expansum were preserved using subculture and maintenance at 4 ºC, mineral oil, drying on silica gel and freeze-drying. Patulin and citrinin production was assessed on yeast extract sucrose agar (YES) and grape juice agar (GJ), using TLC before and after 0.5, 2–3, 6 and 12 months preservation. Citrinin was detected in all cultures for all preservation techniques on YES. The patulin profiles obtained differed with strain and culture media used. Conclusions: Citrinin production seems to be a stable character for the tested strains. There is a tendency for patulin detection with time apparently more consistent for silica gel storage and freeze-drying, especially when the strains are grown on GJ. Significance and Impact of the Study: Variability in the profiles of the mycotoxins tested seems to be more strain-specific than dependent on the preservation technique used
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