Three types of solid waste are produced during beer fermentation: spent grain, hot trub, and residual yeast. While the first is used as livestock feed, the seconds has not yet found any real reapplication in the field of circular economy. The aim of this work is to study and characterize these two brewing wastes, i.e., hot trub and residual yeast, to evaluate their potential reuse in the agricultural field. Samples from top-fermented and bottom-fermented beers were chemically investigated. Initially, the safety was assessed via multi-detection analysis of 57 mycotoxins, and all samples were deemed safe. Subsequently, the chemical and elemental composition was examined via ICP-MS and microanalysis, along with phenolic compounds and antioxidant activity via HPLC and spectrophotometric determinations, to achieve a thorough characterization of these waste samples. The C/N ratio of residual yeast from top-fermented beer and hot trub of the bottom-fermented one were near the optimal one (10:1). This research marks an initial step towards repurposing brewery waste materials as fertilizers. The subsequent steps will involve the formulation and field trials.

• Klíčová slova
• agricultural applications, beer, beer by-products, brewer residual yeast, circular economy, hot trub,
• Publikační typ
• časopisecké články MeSH

Fusarium fungi are widespread pathogens of food crops, primarily associated with the formation of mycotoxins. Therefore, effective mitigation strategies for these toxicogenic microorganisms are required. In this study, the potential of pulsed electric field (PEF) as an advanced technology of increasing use in the food processing industry was investigated to minimize the viability of Fusarium pathogens and to characterize the PEF-induced changes at the metabolomic level. Spores of four Fusarium species (Fusarium culmorum, Fusarium graminearum, Fusarium poae, and Fusarium sporotrichioides) were treated with PEF and cultured on potato dextrose agar (PDA) plates. The viability of the Fusarium species was assessed by counting the colony-forming units, and changes in the mycotoxin content and metabolomic fingerprints were evaluated by using UHPLC-HRMS/MS instrumental analysis. For metabolomic data processing and compound identification, the MS-DIAL (v. 4.80)-MS-CleanR-MS-Finder (v. 3.52) software platform was used. As we found out, both fungal viability and the ability to produce mycotoxins significantly decreased after the PEF treatment for all of the species tested. The metabolomes of the treated and untreated fungi showed statistically significant differences, and PEF-associated biomarkers from the classes oxidized fatty acid derivatives, cyclic hexapeptides, macrolides, pyranocoumarins, carbazoles, and guanidines were identified.

• Klíčová slova
• Fusarium, UHPLC-HRMS/MS, biomarkers, food pathogens, metabolomic fingerprinting, mycotoxins, pulsed electric field, spore viability,
• MeSH
• elektřina * MeSH
• Fusarium * metabolismus   růst a vývoj   MeSH
• metabolom * MeSH
• metabolomika MeSH
• mikrobiální viabilita MeSH
• mykotoxiny * metabolismus   MeSH
• spory hub metabolismus   růst a vývoj   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• mykotoxiny * MeSH

The increasing contamination of cereals by micromycetes and mycotoxins during malting still poses an unresolved food safety problem. This study characterises the potential of the novel, rapidly developing food production technology of Pulsed Electric Field (PEF) to reduce the viability of Fusarium fungi and the production of mycotoxins during malting. Barley, artificially inoculated with four Fusarium species, was treated by PEF with two different intensities and then malted using a standard Pilsner-type technology. Concentrations of fungi were quantified by RT-PCR, expression of fungal growth-related genes was assessed using mRNA sequencing, and mycotoxin levels were analysed by U-HPLC-HRMS/MS. Despite the different trends for micromycetes and mycotoxins after application of variously intense PEF conditions, significant reductions were generally observed. The greatest decrease was for F. sporotrichioides and F. poae, where up to six fold lower levels were achieved for malts produced from the PEF-treated barley when compared to the control. For F. culmorum and F. graminearum, up to a two-fold reduction in the PEF-generated malts was observed. These reductions mostly correlated with a decrease in relevant mycotoxins, specifically type A trichothecenes.

• Klíčová slova
• Fusarium micromycetes, RT-PCR, U-HPLC-HRMS/MS, malting, mycotoxins, pulsed electric field,
• MeSH
• elektřina MeSH
• Fusarium * metabolismus   genetika   růst a vývoj   MeSH
• ječmen (rod) * mikrobiologie   MeSH
• jedlá semena * mikrobiologie   MeSH
• kontaminace potravin prevence a kontrola   MeSH
• manipulace s potravinami metody   MeSH
• mykotoxiny * biosyntéza   metabolismus   MeSH
• potravinářská mikrobiologie MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• mykotoxiny * MeSH

An eleven-year-old Pit Bull Terrier was presented to the veterinary practice with an acute onset of whole-body seizures. The clinical signs developed in a garden where the dog was kept that morning. There was a suspicion of tremorgenic mycotoxin poisoning by compost as the dog had vomited parts of compost right before the onset of the seizures and there was a pile of compost located in the garden. The dog underwent immediate decontamination following supportive treatment and recovered fully within 24 h of intensive care. The samples of the vomit and parts of the compost were cultivated. In the sample of the vomit, Penicillium sp. was found. Subsequently, tremorgenic mycotoxins paxilline, penitrem A and roquefortine C were determined chromatographically at significant concentrations in the vomit and a growth medium with cultivated Penicillium sp. The aim of this work is to describe the complex therapeutic and diagnostic approach to the patient with a suspected tremorgenic mycotoxin poisoning where a combination of mycological and chromatographic analyses was used to confirm the diagnosis. To the best of our knowledge, this is the first confirmed case of canine tremorgenic mycotoxicosis in the Czech Republic and the first reported case of paxilline poisoning in a dog.

• Klíčová slova
• Penicillium sp., chromatography, paxilline, penitrem A, roquefortine C,
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH

Cereals represent a widely consumed food commodity that might be contaminated by mycotoxins, resulting not only in potential consumer health risks upon dietary exposure but also significant financial losses due to contaminated batch disposal. Thus, continuous improvement of the performance characteristics of methods to enable an effective monitoring of such contaminants in food supply is highly needed. In this study, an ultra-high-performance liquid chromatography coupled to a hybrid quadrupole orbitrap mass analyzer (UHPLC-q-Orbitrap MS) method was optimized and validated in wheat, maize and rye flour matrices. Nineteen analytes were monitored, including both regulated mycotoxins, e.g., ochratoxin A (OTA) or deoxynivalenol (DON), and non-regulated mycotoxins, such as ergot alkaloids (EAs), which are analytes that are expected to be regulated soon in the EU. Low limits of quantification (LOQ) at the part per trillion level were achieved as well as wide linear ranges (four orders of magnitude) and recovery rates within the 68-104% range. Overall, the developed method attained fit-for-purpose results and it highlights the applicability of high-resolution mass spectrometry (HRMS) detection in mycotoxin food analysis.

• Klíčová slova
• cereal, ergot alkaloids, high-resolution mass spectrometry, mycotoxins, ultra-high-performance liquid chromatography,
• MeSH
• hmotnostní spektrometrie přístrojové vybavení   metody   MeSH
• jedlá semena chemie   MeSH
• kukuřice setá chemie   MeSH
• mouka analýza   MeSH
• mykotoxiny analýza   MeSH
• pšenice chemie   MeSH
• vysokoúčinná kapalinová chromatografie přístrojové vybavení   metody   MeSH
• žito chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• validační studie MeSH
• Názvy látek
• mykotoxiny MeSH