Introduction and objective: The aim of the study was to determine the presence, concentration and generic composition of filamentous fungi. Selected mycotoxins were also determined: total aflatoxins and deoxynivalenol. Material and methods: In 2017–2018, 40 samples of strawberry fruits...

Introduction and objective: The aim of the study was to determine the presence, concentration and generic composition of filamentous fungi. Considering the significant role of mycotoxins in the pathogenicity of fungal contaminants of vegetables, the scope of the study was extended by...

Substances of organic origin are seeing increasing use in agriculture as rich sources of nutrients for plants. The aim of this study was to determine the microbiological contamination of sewage sludge and digestate to assess their safe use as fertilizers in Poland. The assessment of microbial soil, sewage sludge and digestate contamination was based on the total number of mesophilic bacteria and Gram-negative bacteria from the Enterobacteriaceae family. The presence of Escherichia coli and Salmonella spp. was identified via culture and the presence of Enterobacteriaceae species was determined via biochemical and molecular methods. In laboratory conditions, the survival of E. coli in soil fertilized with sewage sludge or digestate inoculated with a reference strain was determined. The average concentration of Enterobacteriaceae in soil, sewage sludge and digestate samples was 1.1 × 10⁴ CFU/g, 9.4 × 10⁵ CFU/g and 5.6 × 10⁶ CFU/g, respectively. Escherichia coli was detected in all sample types. From the soil samples, Serratia, Enterobacter, Pantoea, Citrobacter and Pseudomonas genera were identified the most frequently, while in sewage sludge and digestate, E. coli was predominant. Based on the results of our laboratory experiment, it can be concluded that after three weeks, fertilization with organic waste in acceptable doses does not significantly increase soil contamination with Enterobacteriaceae.

Microbiological pollutants of cabin filters may affect the air quality inside vehicles. The main aim of the study was to evaluate cabin filters in terms of their effectiveness in retaining mycological contaminants. The research material consisted of 100 cabin filters obtained during periodic replacement of filters in passenger cars. Mycological contamination of filters was examined using microbiological, biochemical, immunoenzymatic and molecular methods. The average concentration of fungi in cabin filters was 7.2 × 10⁷ CFU/m², and Cladosporium, Alternaria, Penicillium, and Aspergillus genera were most often isolated. For Aspergillus species, the highest concentration reached 3.3 × 10⁷ CFU/m², with dominance of A. fumigatus. Among the Aspergillus strains tested, the presence of the aflO gene related to aflatoxin biosynthesis and the polyketide synthase gene related to ochratoxin A biosynthesis was detected. The presence of total aflatoxin (B₁, B₂, G₁, G₂) and aflatoxin B₁ was detected at levels of 5.37 µg/kg and 1.71 µg/kg for standard filters and 2.43 µg/kg and 0.65 µg/kg for carbon filters. The level of ochratoxin A contamination was 0.96 µg/kg and 0.55 µg/kg for standard and carbon filters, respectively. Aspergillus species showed high enzymatic activity of acid phosphatase, β-glucosidase, naphthol phosphohydrolase and N-acetyl-β-glucosamidase. Based on the test results regarding the concentration of mycotoxins and the effectiveness of capturing fungal conidia, it was found that carbon filters are more effective than standard filters. Recommendations for filter manufacturers and car service policies should include the use of cabin filters with a layer of activated carbon, and their regular replacement after a year of use.

Introduction: Between 2015–2020, the concentrations and diversity of filamentous fungi as well as the levels of mycotoxins in 4 classes of vegetables and fruits were studied in samples from farms located in eastern Poland. The short communication summarizes the results with the use of...

Fresh, minimally processed foods contain many valuable nutrients but are also a source of pathogenic microorganisms. This study aimed to investigate the presence of filamentous fungi and mycotoxin contamination in leafy vegetables. A total of 160 samples of lettuce, spinach, mixed salads, and sprouts from markets and gardens were tested. Fungal strains were cultured on Malt Extract Agar with chloramphenicol (50 mg/L). Fungal identification was performed by macroscopic and microscopic observations, amplification of the small subunit rRNA (SSU rRNA) gene fragment, and sequencing. Total aflatoxins, aflatoxin B1, and zearalenone contents were determined using the ELISA method. The mean concentrations of filamentous fungi in fresh and minimally processed vegetables were 9.4 × 10² CFU/g and 3.4 × 10² CFU/g, respectively. Nineteen fungal genera were identified, in addition to non-sporulating fungi, of which the largest percentage comprised the genera Cladosporium (38%), Alternaria (37%), and Fusarium (30%), and less frequently Penicillium, Mucor, Trichoderma, and Aspergillus (from 8 to 14% of positive samples). The highest percentage of samples contaminated with zearalenone was observed in the spinach group. Ready-to-eat leafy vegetables should be monitored for contamination with filamentous fungi and mycotoxins as they pose a potential risk to consumer health.