26 research outputs found

    Analytical techniques for determination of mycotoxins in barley, malt and beer: A review

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    The increasing interest in defining the content of mycotoxins is related to the development of methods for their determination. Several methods of determination have been published. This paper describes analytical procedures such as (a) sample preparation – sampling and homogenization, (b) extraction and purification – solid phase extraction (SPE), a QuEChERS method (acronymic name from quick, easy, cheap, effective, rugged and safe), solid-liquid extraction (SLE) and immuno affinity extraction (IAE). It also provides a review of, (c) instruments, and other analytical methods such as thin layer chromatography (TLC), enzyme linked immune sorbent assay (ELISA) and liquid chromatography (LC), gas chromatography (GC) with different detectors for determination of mycotoxin in barley, malt and beer are discussed

    Beer industry in Brazil: Economic aspects, characteristics of the raw material and concerns

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    Barley is one of the most cultivated grains in the world with numbers rising every year due to market demand. In the past decade, Brazil has shown impressive numbers considering beer production. However, barley cultivation does not reach the necessary amount for the beer industry which raises the need to import barley or to use some alternatives, such as, adjuncts. The most common adjunct used is corn, which is considered a good source of carbohydrates, but also a very contaminated grain. Research and monitoring of all of the steps of the chain is being carried out to improve not only the malt quality but also the competitiveness in world market

    Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition)

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    In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. For example, a key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process versus those that measure fl ux through the autophagy pathway (i.e., the complete process including the amount and rate of cargo sequestered and degraded). In particular, a block in macroautophagy that results in autophagosome accumulation must be differentiated from stimuli that increase autophagic activity, defi ned as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (inmost higher eukaryotes and some protists such as Dictyostelium ) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the fi eld understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. It is worth emphasizing here that lysosomal digestion is a stage of autophagy and evaluating its competence is a crucial part of the evaluation of autophagic flux, or complete autophagy. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. Along these lines, because of the potential for pleiotropic effects due to blocking autophagy through genetic manipulation it is imperative to delete or knock down more than one autophagy-related gene. In addition, some individual Atg proteins, or groups of proteins, are involved in other cellular pathways so not all Atg proteins can be used as a specific marker for an autophagic process. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field

    Mycoflora and deoxynivalenol in whole wheat grains (Triticum aestivum L.) from Southern Brazil.

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    Fungi species Fusarium graminearum is related to deoxynivalenol (DON) formation. The aim of this study was to evaluate mycoflora and DON occurrence in 53 whole wheat grains samples collected in Southern Brazil during the 2012 crop. Wheat grains showed adequate values of water activity ranging from 0.48-0.72, within the required limits of moisture content, ranging from 9.1-13.9%. In addition low counts for fungal colonies, ranging from 10 to 8.2x102 were found. For Fusarium genera there was predominance of F. verticillioides (34%) and F. graminearum (30.2%). For Aspergillus species, 37.7% A. flavus was determined. Regarding the Penicillium species, P. digitatum (49%) was the most found species. DON was detected in 47.2% (25 out of 53) of the samples analyzed, with levels from 243.7 to 2281.3 ?g kg-1 (mean: 641.9 ?g kg-1)

    Pivovarský průmysl v Brazílii: Ekonomické aspekty, charakteristika surovin a rizika

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    Barley is one of the most cultivated grains in the world with numbers rising every year due to market demand. In the past decade, Brazil has shown impressive numbers considering beer production. However, barley cultivation does not reach the necessary amount for the beer industry which raises the need to import barley or to use some alternatives, such as, adjuncts. The most common adjunct used is corn, which is considered a good source of carbohydrates, but also a very contaminated grain. Research and monitoring of all of the steps of the chain is being carried out to improve not only the malt quality but also the competitiveness in world market646284286Ječmen je jednou z nejvíce pěstovaných obilovin na světě, po níž se každoročně zvyšuje poptávka na trhu. V uplynulém desetiletí vykazuje Brazílie působivá data, pokud jde o výrobu piva. Pěstování ječmene však nedosahuje potřebného množství pro výrobu piva, což vyvolává potřebu dovozu ječmene nebo využití některých alternativ, např. surogace. Nejběžnějším přídavkem je kukuřice, která je považována za dobrý zdroj sacharidů, ale je zde riziko kontaminace zrn. Výzkum a sledování všech kroků řetězce probíhá s cílem zlepšit nejen kvalitu sladu, ale také konkurenceschopnost na světovém trh

    Assessment of Toxigenic Fusarium Species and Their Mycotoxins in Brewing Barley Grains

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    Fusarium species threaten yield and quality of cereals worldwide due to their ability to produce mycotoxins and cause plant diseases. Trichothecenes and zearalenone are the most economically significant mycotoxins and are of particular concern in barley, maize and wheat. For this reason, the aim of this study was to characterize the Fusarium isolates from brewing barley and to assess deoxynivalenol and zearalenone contamination in grains. Characterization of the Fusarium strains was carried out by the phylogeny based on two loci (EF-1α and RPB2). Mycotoxin detection and quantification were performed by LC-MS. The results show that Fusarium was the predominant genus. Phylogenetic study demonstrated that the majority of the strains clustered within the Fusarium sambucinum species complex followed by the Fusarium tricinctum species complex. The results revealed high incidence of deoxynivalenol (DON) and zearalenone (ZEA) contamination (90.6% and 87.5%, respectively). It was observed that 86% of the samples contaminated with ZEA were above the limits set by the EU and Brazilian regulations. These results may highlight the importance of controlling Fusarium toxins in barley, mainly because of its use in the brewing industry and the resistance of various mycotoxins to food processing treatments

    NIR spectroscopy and chemometric tools to identify high content of deoxynivalenol in barley

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    Deoxynivalenol (DON) is one of the mycotoxins produced mainly by the Fusarium graminearum species complex in small grain cereals, including barley. This toxin can cause alimentary disorders, immune function depression and gastroenteritis. The negative health effects associated with DON coupled to the increasing concern about green and rapid methods of analysis motivated this study. In this context, near infrared (NIR) spectroscopy data were applied for exploratory analysis to distinguish barley with high and low levels of DON contamination (> or <1250 µg/kg according to the European Union threshold), by Partial Least Squares-Discriminant Analysis (PLS-DA), and to verify the performance of Partial Least Squares-Regression (PLS-R) to predict DON concentration in barley samples. Maximum values of specificity and sensitivity were achieved in the calibration set; 90.9% and 81.9% were observed in the cross-validation set for the PLS-DA classification model. PLS-R quantification of DON in barley presented low values of error (RMSEC = 101.94 µg/kg and RMSEP = 160.76 µg/kg). Thus, we found that NIR in combination with adequate chemometric tools could be applied as a green technique to monitor DON contamination in barley37915421552CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP142414 / 2016-6Sem informação2017/04811-

    Occurrence of deoxynivalenol and zearalenone in brewing barley grains from Brazil

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    Barley (Hordeum vulgare L.) is an important cereal crop for food and represents one of the main ingredients in beer production. Considering the importance of barley and its derived products, the knowledge about the mycotoxin contamination in the barley production is essential in order to assess its safety. In this study, the levels of deoxynivalenol (DON) and zearalenone (ZEN) in brewing barley were determined using a LC-MS/MS method. A survey was conducted in 2015 to estimate the mycotoxin levels in these products (n = 76) from four crop regions in Brazil. The results showed high levels of DON and ZEN in the analyzed samples, with contamination levels of 94 and 73.6%, respectively. The mean levels of DON and ZEN ranged from 1700 to 7500 μg/kg and from 300 to 630 μg/kg, respectively. Barley samples from regions 1 and 2 presented higher levels of ZEN and DON, respectively, and those from region 4 presented lower levels of both. Co-occurrence of DON and ZEN was seen in the majority of the barley grain samples, and the mycotoxin content was above the maximum levels established by the Brazilian and European regulatio34173178FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP2016/01798–

    From T-coalgebras to filter structures and transition systems

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    Abstract. For any set-endofunctor T: Set → Set there exists a largest subcartesian transformation µ to the filter functor F: Set → Set. Thus we can associate with every T-coalgebra A a certain filter-coalgebra AF. Precisely, when T weakly preserves preimages, µ is natural, and when T weakly preserves intersections, µ factors through the covariant powerset functor P, thus providing for every T-coalgebra A a Kripke structure AP. The paper characterizes weak preservation of preimages, of intersections, and preservation of both preimages and intersections by a functor T via the existence of transformations from T to either F or P. Moreover, we define for arbitrary T-coalgebras A a next-time operator ○A with associated modal operators ✷ and ✸ and relate their properties to weak limit preservation properties of T. In particular, for any T-coalgebra A there is a transition system K with ○A = ○K if and only if T weakly preserves intersections. 1

    Characterization of the fusarium sambucinum species complex and detection of multiple mycotoxins in brazilian barley samples

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    This study investigated the fungal diversity in Brazilian barley samples, focusing on the Fusarium sambucinum species complex and the presence of multiple mycotoxins: aflatoxins B1, B2, G1, G2 beauvericin (BEA), enniatins (ENNs) A, A1, B, and B1, deoxynivalenol (DON), fumonisins (FB) B1 and B2, HT-2 and T-2 toxins, nivalenol (NIV) and ochratoxin A (OTA) from two different regions, São Paulo (SP) and Rio Grande do Sul (RS). The majority of the isolates belonged to the Fusarium sambucinum species complex (FSAMSC), with F. graminearum s.s. characterized as the major contaminant. F. meridionale and F. poae were the second most frequent fungi isolated from SP and RS, respectively. All of the F. graminearum s.s. isolates demonstrated 15-ADON genotype, whereas F. poae and F. meridionale were all NIV. The majority of the F. cortaderiae isolates were NIV, with only one 3-ADON genotype. Mycotoxin analysis revealed that none of the samples were contaminated by aflatoxins, OTA, FB2 and type A trichothecenes, however, all of the samples were contaminated with at least one Fusarium toxin. Contamination by DON, ZEA, ENNB and ENNB1 levels were significantly higher in RS. Co-contamination of BEA, DON, ENNs, NIV and ZEA in 18.5% and 24.2% of the analyzed samples was observed, from SP and RS respectively. More than 20% of the samples from RS presented DON and ZEA levels above the regulations established by Europe and Brazil. The results provide further information on the FSAMSC from South America and detected multiple Fusarium toxins in barley samples. This highlights the importance for further studies on the possible interactions of these mycotoxins in order to determine potential risks to animal health136CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP167039/2017-2Sem informação2017/04811-
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