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Penicillium spp. produce a great variety of secondary metabolites, including several mycotoxins, on food substrates. Chestnuts represent a favorable substrate for Penicillium spp. development. In this study, the genomes of ten Penicillium species, virulent on chestnuts, were sequenced and annotated: P. bialowiezense. P. pancosmium, P. manginii, P. discolor, P. crustosum, P. palitans, P. viridicatum, P. glandicola, P. taurinense and P. terrarumae. Assembly size ranges from 27.5 to 36.8 Mb and the number of encoded genes ranges from 9,867 to 12,520. The total number of predicted biosynthetic gene clusters (BGCs) in the ten species is 551. The most represented families of BGCs are non ribosomal peptide synthase (191) and polyketide synthase (175), followed by terpene synthases (87). Genome-wide collections of gene phylogenies (phylomes) were reconstructed for each of the newly sequenced Penicillium species allowing for the prediction of orthologous relationships among our species, as well as other 20 annotated Penicillium species available in the public domain. We investigated in silico the presence of BGCs for 10 secondary metabolites, including 5 mycotoxins, whose production was validated in vivo through chemical analyses. Among the clusters present in this set of species we found andrastin A and its related cluster atlantinone A, mycophenolic acid, patulin, penitrem A and the cluster responsible for the synthesis of roquefortine C/glandicoline A/glandicoline B/meleagrin. We confirmed the presence of these clusters in several of the Penicillium species conforming our dataset and verified their capacity to synthesize them in a chestnut-based medium with chemical analysis. Interestingly, we identified mycotoxin clusters in some species for the first time, such as the andrastin A cluster in P. flavigenum and P. taurinense, and the roquefortine C cluster in P. nalgiovense and P. taurinense. Chestnuts proved to be an optimal substrate for species of Penicillium with different mycotoxigenic potential, opening the door to risks related to the occurrence of multiple mycotoxins in the same food matrix., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Brown and black spots, caused by Stemphylium and Alternaria species, are important fungal diseases affecting European pear ( Pyrus communis ) in orchards. Both fungal genera cause similar symptoms, which could favor misidentification, but Alternaria spp. are increasingly reported due to the changing climatic conditions. In this study, Alternaria spp. were isolated from symptomatic leaves and fruits of European pear, and their pathogenicity was evaluated on pear fruits from cultivar Abate Fétel, and molecular and chemical characterization were performed. Based on maximum likelihood phylogenetic analysis, 15 of 46 isolates were identified as A. arborescens species complex (AASC), 27 as A. alternata , and four as Alternaria sp. Both species were isolated from mature fruits and leaves. In pathogenicity assays on pear fruits, all isolates reproduced the symptoms observed in the field, by both wound inoculation and direct penetration. All but one isolate produced Alternaria toxins on European pears, including tenuazonic acid and alternariol (89.1% of the isolates), alternariol monomethyl ether (89.1%), altertoxin I (80.4%), altenuene (50.0%), and tentoxin (2.2%). These isolates also produced at least two mycotoxins, and 43.5% produced four mycotoxins, with an average total concentration of the Alternaria toxins exceeding 7.58 × 10 6 ng/kg. Our data underline the potential risks for human health related to the high mycotoxin content found on fruits affected by black spot. This study also represents the first report of AASC as an agent of black spot on European pear in Italy.

A collection of 124 isolates of Penicillium spp. was created by monitoring fresh chestnuts, dried chestnuts, chestnut granulates, chestnut flour and indoor chestnut mills. Sequencing of the ITS region, β-tubulin and calmodulin, macro-morphology and secondary metabolite production made it possible to determine 20 species of Penicillium. P. bialowiezense was dominant in the fresh chestnuts, while P. crustosum was more frequent in the other sources. A pathogenicity test on chestnut showed that around 70% of the isolates were virulent. P. corylophilum and P. yezoense were not pathogenic, while the other 18 species had at least one virulent isolate. P. expansum and P. crustosum were the most virulent. The isolates were characterized to establish their ability to produce 14 toxic metabolites in vivo: 59% were able to produce at least one mycotoxin. P. expansum was able to produce patulin, chaetoglobosin A and roquefortine, while P. bialowiezense produced C. Mycophenolic acid. Cyclopenins and viridicatins were produced by most of the P. crustosum, P. polonicum, P. solitum and P. discolour isolates. Some of the P. crustosum isolates were also able to produce roquefortine C or penitrem A. Information about the occurrence of Penicillium spp. and their mycotoxins will help producers to set up management procedures that can help to control the fungal growth and the mycotoxin production of chestnuts., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Pistachio (Pistacia vera) is an important nut for its economic, nutritional and health aspects but it can be contaminated by aflatoxigenic fungi in the field and during storage. Biological control could be considered as an alternative to chemical treatment. In this study, we evaluated the antifungal and anti-mycotoxigenic capability of two Bacillus spp. both in vitro and on pistachio kernels. In in vitro conditions, both strains were able to reduce the mycelial growth and they were able to degrade the four aflatoxins during the first three days after inoculation. AFG 1 and AFG 2 were rapidly degraded within two days of incubation with the bacterial strains. No aflatoxin was found in the bacterial cell walls, permitting exclusion of mycotoxin adsorption and hypothesis of an in vitro biodegradation as a mode of action. The cultivar of pistachio most susceptible to fungal colonization was 'Ahmad-Aghaei', selected among four main Iranian cultivars. A. parasiticus was able to grow and produce aflatoxins on pistachios, but at longer inoculation periods, a natural decrease of aflatoxins was registered. Both strains were able to reduce the fungal incidence and number of spores on pistachio with a stronger effect during the first 5dpi. The effect on aflatoxin content in vivo was less pronounced than in vitro, with a maximum effect at 8dpi. At longer times, there was a contrasting effect due to the lower activity of Bacillus spp. in stationary phase and higher growth of Aspergillus species. This consideration could explain the lack of aflatoxin reduction at 12dpi. Both bacterial strains showed good antifungal activity and aflatoxin reduction in in vitro conditions and on pistachio kernels. Altogether, these results indicate that Bacillus species could be considered as potential biocontrol agents to combat toxigenic fungal growth and subsequent aflatoxin contamination of nuts and agricultural crops in practice., (Copyright © 2017. Published by Elsevier B.V.)

A new method for the detection of alternariol (AOH), alternariol monomethyl ether (AME), altenuene (ALT), tentoxin (TEN), and tenuazonic acid (TeA), five alternaria toxins (ATs) was developed by liquid chromatography-triple quadrupole mass spectrometry equipped with atmospheric pressure chemical ionisation (APCI). A single extraction was used to recover the five ATs by apple juices, beers, tomato sauces, olives and dried basil. Different Solid Phase Extractions (SPE) and clean-up were selected to optimise the purification step for each food matrix. Limits of detection and quantification were, respectively, in the range 0.16-12.31 and 0.54-41.04 ng g(-1). Recovery rates were generally above 70%, except for dried basil and olives. Thirty out of 70 samples analysed (7 apple juices, 14 beers and 9 tomato sauces) resulted positive to at least one alternaria toxin investigated. AOH was the most common AT (14 samples), followed by ALT (10 samples). The highest concentration of ATs was found in commercial apple juices (35.33 ng g(-1))., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Mycotoxins, such as aflatoxins and ochratoxin A, are presently considered as the most important chronic dietary risk factor, more than food additives or pesticide residues. Therefore, the serious health and economic consequences of mycotoxin contamination have created the need for rapid, sensitive, and reliable techniques to detect such dangerous molecules within foodstuffs. We here report on the development of an innovative immunosensing method for mycotoxin detection, based on antibody-immobilized microcantilever resonators, a promising label free biosensing technique. A considerable part of the work is devoted to show the effect on microcantilever resonance frequency of the composition of the incubation buffer, as well as of the washing and drying procedure. We show the feasibility of using microcantilever resonator arrays to effectively identify total aflatoxins and ochratoxin A, at low concentrations (3 ng/mL and less than 6 ng/mL, respectively), with relatively low uncertainty (about 10%) and good reproducibility for the same target concentration. Furthermore, the developed immunosensing method shows a limited cross-reactivity to different mycotoxins, paving the way to a highly specific technique, able to identify different mycotoxins in the sample. To our knowledge, this work represents the first example in literature of successfully immunodetection of low concentrations of multiple mycotoxins by microcantilever resonator arrays., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Aims To identify cultivable filamentous fungi before ensiling, after silage conservation, in farm-silos covered with two different plastic films (polyethylene (PE) vs biodegradable (MB)), as well as after aerobic exposure of whole-crop corn silage. Methods and Results Molecular techniques coupled with traditional microbial counting were utilized to identify the predominant fungal species. The cultivable fungal population changed remarkably from harvesting to silo opening. Anaerobiosis and low pH reduced mould count and the presence of Fusarium species both under PE and MB film. However, in the peripheral areas of the silo, where air penetration could not be completely prevented, the fungal population did not decrease. The predominant fungal species after aerobic exposure of silage was Aspergillus fumigatus, without differences between the two plastic films. Conclusions Maintenance of anaerobiosis and a low pH also in the upper layer of the silo reduce the risk of mould growth during corn silage feed-out. Significance and Impact of the Study Even if the new MB plastic film did not completely maintain the anaerobiosis in the upper layer of silage, the overall silage quality was not compromised and was similar to that observed under PE, indicating that the development and use of MB film to cover silage is promising, but needs some improvement. [ABSTRACT FROM AUTHOR]

Abstract: Italy is one of the countries where ochratoxin A (OTA) contamination in wine poses more risks. Previous surveys on the occurrence of OTA have poorly considered north Italian wines. In this study, 1206 red and white DOC and DOCG wines produced in Piedmont (Northern Italy) from 2000 to 2007 have been analyzed for OTA level (0.116μgl−1) and incidence (68.0%). The monitoring – the widest per number of Italian wine samples considered – analyzed the OTA contamination of wines in tanks just before bottling. OTA level and incidence were significantly higher in red (0.121μgl−1, 69.4%) than in white (0.086μgl−1, 61.3%) wines. Among the white wines, the incidence was significantly lower in the Moscato wines (7.3%), due to the different wine processing. The differences in the mean OTA level in the three main grapevine varieties of red wines could be related to the harvest period. Among the Nebbiolo appellations, a reduction of the OTA level was noticed with increasing the wood aging period. A significant effect of the vintage year was also registered. [Copyright &y& Elsevier]

Pear, peach, apricot, and mixed juices (125 samples) were purchased in Italian supermarkets and organic food shops and analysed for patulin content. An overall incidence of 34.4? was observed in the fruit juices, with a mean contamination level of 3.6 µg kg-1. No one sample exceeded 50 µg kg-1, the maximum permitted limit according to European legislation. However, 19 positive samples contained more than 10 µg kg-1 of patulin, which is the maximum level permitted for baby food. The incidence of patulin contamination was significantly higher in pear juices (64.1?) than in apricot, peach, or mixed juices. Statistical analysis (p = 0.002; Kruskal-Wallis test) showed a significantly higher level of patulin in pear (5.1 µg kg-1) and mixed juices (4.9 µg kg-1) than in the other juices. A slightly higher incidence of positive samples was found in conventional juices (35.7?) compared with the organic ones (29.6?). The magnitude between the mean contamination levels was similar in conventional (3.6 µg kg-1) and organic (3.3 µg kg-1) juices (p = 0.474; Mann-Whitney U-test). Samples were further divided based on the fruit content in fruit juices, fruit nectars, and fruit drinks. In fruit nectars the incidence of positive samples (37.8?) was slightly higher than in fruit drinks (27.2?), but the mean patulin contamination was higher in fruit drinks (5.2 µg kg-1) than in fruit nectars (3.4 µg kg-1). However, the magnitude between the two means was not statistically different (p = 0.734; Mann-Whitney U-test). Italian juices had a higher incidence of patulin (35.3?), with a lower mean content (3.5 µg kg-1), compared with the incidence (22.2?) and level (4.1 µg kg-1) foreign juices commercially available in Italy. The magnitude of the means between Italian and foreign juices was not statistically different, according to the Mann-Whitney U-test (p = 0.616). The estimated intake of patulin ranged from 0.1 to 1.5 ng kg-1 body weight for the whole population and from 0.3 to 5.1 ng kg-1 body weight for the consumers only. The highest patulin intake was estimated for consumers of pear juices, followed by consumers of mixed juices. The daily intake of patulin derived from the consumption of pear juice suggests that also pear juices, though a minor patulin source, could be monitored for their patulin content in order to control the mycotoxin contamination, especially in countries, such as Italy, where pear nectars are preferred as fruit drinks. [ABSTRACT FROM AUTHOR]