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Introduction: Aflatoxins are among the most carcinogenic natural compounds known, and have been frequently detected in numerous agricultural commodities, nut fruits being among the most contaminated ones. These toxins are a result of the secondary metabolism of fungi belonging to the genus Aspergillus Section Flavi, namelly Aspergillus flavus, A. parasiticusand A. nomius. The early detection of aflatoxigenic fungal contamination and the preventive control of aflatoxin production seems to be the only viable way to respond to the rigorous limits imposed by EU legislation. In Portugal, knowledge on mycoflora and mycotoxigenic profiles of almonds is scarce. Our objective was to characterise portuguese almonds in respect to mycoflora, with strong emphasis on aflatoxigenic fungi, from production to ...

Aflatoxins are among the most carcinogenic natural compounds known, and have been frequently detected in numerous agricultural commodities, nut fruits being among the most contaminated ones. These toxins are a result of the secondary metabolism of fungi belonging to the genus Aspergillus Section Flavi, namelly Aspergillus flavus, A. parasiticus and A. nomius. The early detection of aflatoxigenic fungal contamination and the preventive control of aflatoxin production seems to be the only viable way to respond to the rigorous limits imposed by EU legislation. In Portugal, knowledge on mycoflora and mycotoxigenic profiles of almonds is scarce. Our objective was to characterise portuguese almonds in respect to mycoflora, with strong emphasis on aflatoxigenic fungi, from production to commercialization. Various samples of almonds were collected from the field, as well as during storage and processing. Environmental data have also been recorded. Samples were plated directly on MEA+10% NaCl and all fungi belonging to the genus Aspergillus isolated and identified to the group or species level. All Aspergillus belonging to Section Flavi were further characterised based on their mycotoxigenic profile, with the aim of identifying aflatoxigenic and non-aflatoxigenic strains. Fungal diversity and relative frequencies of Aspergillus spp. were determined for the various samples and correlated with environmental conditions. We have observed a progressive reduction on fungal diversity of almonds from the field to the end of processing, as well as an increase of the frequency of more xerophilic fungi, including Aspergillus Section Flavi. Concerning the latter, we report that Aspergillus parasiticus are predominantly aflatoxigenic and Aspergillus flavus are predominantly non-aflatoxigenic. Other less common species have also been identified.

Aflatoxins are among the most carcinogenic natural compounds known, and have been frequently detected in numerous agricultural commodities, nut fruits being among the most contaminated ones. These toxins are a result of the secondary metabolism of fungi belonging to the genus Aspergillus Section Flavi, namelly Aspergillus flavus, A. parasiticus and A. nomius. The early detection of aflatoxigenic fungal contamination and the preventive control of aflatoxin production seems to be the only viable way to respond to the rigorous limits imposed by EU legislation. In Portugal, knowledge on mycoflora and mycotoxigenic profiles of almonds is scarce. Our objective was to characterise portuguese almonds in respect to mycoflora, with strong emphasis on aflatoxigenic fungi, from production to commercialization. Various samples of almonds were collected from the field, as well as during storage and processing. Environmental data have also been recorded. Samples were plated directly on MEA+10% NaCl and all fungi belonging to the genus Aspergillus isolated and identified to the group or species level. All Aspergillus belonging to Section Flavi were further characterised based on their mycotoxigenic profile, with the aim of identifying aflatoxigenic and non-aflatoxigenic strains. Fungal diversity and relative frequencies of Aspergillus spp. were determined for the various samples and correlated with environmental conditions. We have observed a progressive reduction on fungal diversity of almonds from the field to the end of processing, as well as an increase of the frequency of more xerophilic fungi, including Aspergillus Section Flavi. Concerning the latter, we report that Aspergillus parasiticus are predominantly aflatoxigenic and Aspergillus flavus are predominantly non-aflatoxigenic. Other less common species have also been identified.

The taxonomy of the penicillia is unstable particularly in the important antibiotic-and mycotoxin-producing subgenus Penicillium. There are difficulties relating identifications to mycotoxin production. Also, the validity of dual nomenclature for pleomorphic fungi is under discussion increasingly. Patulin is an important mycotoxin produced by various fungi and has strict limits in the European Union. The mycotoxin and/or the isoepoxydon dehydrogenase (IDH) gene of the metabolic pathway have been assessed in 318 strains predominately of subgenus Penicillium. These data were used to classify the isolates. Subgenus Penicillium contained most of the IDH and patulin positives. The species and varieties in subgenus Penicillium which were associated with patulin detection can be reduced to one name, viz. Penicillium Pen p+ (p=patulin). This as been extended to other mycotoxin producing penicillia to indicate the scope of the scheme. The classification will lead to the number of taxa being reduced, while avoiding species names and hence dual nomenclature. Culture independent analysis of environmental samples is mentioned. The scheme could be used with advantage for other fungi. ; Fundação para a Ciência e a Tecnologia ...

Interactions between fungi occur when they grow on the same host plant. This is the case of Botrytis cinerea and Penicillium expansum on grape. P. expansum is also responsible for production of the mycotoxin patulin. In this study, the influence of the interaction between both fungi on fungal growth parameters was studied as well as the effect on the accumulation of patulin by P. expansum. For that purpose, spores of B. cinerea and P. expansum were inoculated together (mixed inoculum), and the parameters growth rate, time for growth and patulin accumulation were assessed. The presence of P. expansum conidia shortened the time for growth of mixed inoculum colonies which, at the end of incubation, were B. cinerea-like. Although some P. expansum growth was observed in mixed inoculum colonies, very low levels of patulin were observed. In assays carried out in patulin-spiked medium, B. cinerea was capable to metabolize the mycotoxin. The capabilities of B. cinerea to shorten time for growth and prevent patulin accumulation are competing abilities that facilitate grape colonization. Significance and Impact of the Study: To our knowledge, this is the first study on the influence of fungal interactions between Botrytis cinerea and Penicillium expansum on growth parameters and patulin accumulation. The incidence of P. expansum in some wine regions is high, but the attack of this fungus to vineyards is rare, being B. cinerea the most common disease. In this assay, it was observed that, in vitro, the presence of P. expansum spores enhanced B. cinerea growth, while the latter avoided patulin accumulation. ; H. Morales is grateful to the Portuguese Government. (Ministerio da Ciencia, Tecnologia e Ensino Superior; FCT Fundacao para a Ciencia e a Tecnologia. Grant ref. ...

The phase diagrams of Ucon 50-HB5100/sodium citrate aqueous two-phase systems were determined at 5, 20 and 40 ◦C. Two medium pHs 5.20 and 8.20 were assayed. The binodal curves were satisfactorily described using a four-parameter sigmoidal equation. The two-phase area was expanded by increasing both pH and temperature. The reliability of the measured tie line compositions was ascertained by correlation equations given by Othmer–Tobias and Bancroft. ; VALNATURA ; CONICET ; ALFA II-0440-FA-Exchange programme between Universities of the European Union and Latin ...

Two phase olive mill waste (TPOMW) is presently the major waste produced by the olive mill industry. This waste has potential to be used as substrate for solid state fermentation (SSF) despite of its high concentration of phenolic compounds and low nitrogen content. In this work, it is demonstrated that mixtures of TPOMW with winery wastes support the production of lipase by Aspergillus spp. By agar plate screening, Aspergillus niger MUM 03.58, Aspergillus ibericus MUM 03.49 and Aspergillus uvarum MUM 08.01 were chosen for lipase production by SSF. Plackett-Burman experimental design was employed to evaluate the effect of substrate composition and time on lipase production. The highest amounts of lipase were produced by A. ibericus on a mixture of TPOMW, urea and exhausted grape mark (EGM). Urea was found to be the most influent factor for the lipase production. Further optimization of lipase production by A. ibericus using a full factorial design (32) conducted to optimal conditions of substrate composition (0.073 g urea/g and 25% of EGM) achieving 18.67 U/g of lipolytic activity. ; Jose Manuel Salgado is grateful for Postdoctoral fellowship (EX-2010-0402) of Education Ministry of Spanish Government. Luis Abrunhosa was supported by the grant SFRH/BPD/43922/2008 from Fundacao para a Ciencia e Tecnologia-FCT, Portugal. Authors thank Fundacao para a Ciencia e a Tecnologia (FCT) for financial support through the project FCT ...

Wastes from olive oil and wine industries (as exhausted grape marc, vineshoot trimmings, two-phase olive mill waste, vinasses, and olive mill wastewater) were evaluated for lignocellulolytic enzyme production (as endocellulases, endoxylanases, and feruloyl esterases) by solid-state fermentation (SSF) with Aspergillus niger, Aspergillus ibericus, and Aspergillus uvarum. To study the effect of different solid medium composition and time in enzyme production, a PlackettBurman experimental design was used. Variables that had a higher positive effect in lignocellulolytic enzyme production were urea, time, and exhausted grape marc. The maximum values of enzymatic activity per unit of substrate dry mass were found with A. niger for feruloyl esterase. Enzymatic extracts from SSF with A. niger achieved maximum feruloyl esterase activity (89.53 U/g) and endoxylanase activity (3.06 U/g) and with A. uvarum for endocellulase activity (6.77 U/g). The enzyme cocktails obtained in the SSF extracts may have applications in biorefinery industries. ; Jose Manuel Salgado is grateful for the postdoctoral fellowship (EX-2010-0402) of the Education Ministry of Spanish Government. Luis Abrunhosa was supported by the grant SFRH/BPD/43922/2008 from Fundacao para a Ciencia e Tecnologia-FCT, ...

Maize is the principal staple food/feed crop exposed to mycotoxins, and the co-occurrence of multiple mycotoxins and their metabolites has been well documented. This review presents the infection cycle, ecology, and plant-pathogen interactions of Aspergillus and Fusarium species in maize, and current knowledge on maize chain management to mitigate the occurrence of aflatoxins and fumonisins. Preventive actions include at pre-harvest, as part of cropping systems, at harvest, and at postharvest, through storage, processing, and detoxification to minimize consumer exposure. Preventive actions in the field have been recognized as efficient for reducing the entrance of mycotoxins into production chains. Biological control of Aspergillus flavus has been recognized to minimize contamination with aflatoxins. Post-harvest maize grain management is also crucial to complete preventive actions, and has been made mandatory in government food and feed legislation. ; This review was prepared as part of MYCHIF EFSA project (GP/EFSA/AFSCO/2016/01). Roberta Palumbo carried out this work within the PhD school Agrisystem of Università Cattolica del Sacro Cuore, Italy. This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684) 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. This paper was critically reviewed in collaboration with MycoKey project (Horizon 2020, Grant Agreement No. 678781). ...

Maize is the principal staple food/feed crop exposed to mycotoxins, and the co-occurrence of multiple mycotoxins and their metabolites has been well docu- mented. This review presents the infection cycle, ecology, and plant-pathogen interac- tions of Aspergillus and Fusarium species in maize, and current knowledge on maize chain management to mitigate the occurrence of aflatoxins and fumonisins. Preven- tive actions include at pre-harvest, as part of cropping systems, at harvest, and at post- harvest, through storage, processing, and detoxification to minimize consumer expo- sure. Preventive actions in the field have been recognized as efficient for reducing the entrance of mycotoxins into production chains. Biological control of Aspergillus flavus has been recognized to minimize contamination with aflatoxins. Post-harvest maize grain management is also crucial to complete preventive actions, and has been made mandatory in government food and feed legislation.