Authors studied the effect of sterigmatocystin from infected corn (STC), purified sterigmatocystin (PSTC), and aflatoxin B1 from infected corn (AFB₁) on lipid peroxidation and glutathione redox parameters, including the expression of their encoding genes in a sub-chronic (14 days) trial. A total of 144 three-week-old cockerels was divided into four experimental groups (n = 36 in each). Control feed was contaminated with STC or PSTC (1590 µg STC/kg or 1570.5 µg STC/kg feed), or with AFB₁ (149.1 µg AFB₁/kg feed). Six birds from each group were sampled at day 1, 2, 3, 7 and 14 of mycotoxin exposure. As parameters of lipid peroxidation, conjugated dienes (CD) and trienes (CT) were measured in the liver, while malondialdehyde (MDA) concentration was determined in blood plasma, red blood cell hemolysate and liver. Reduced glutathione (GSH) concentration and glutathione peroxidase (GPx) activity were determined in the same samples, and expression of glutathione peroxidase 4 (GPX4), glutathione synthetase (GSS) and glutathione reductase (GSR) genes was measured by RT-PCR in the liver. STC, PSTC or AFB₁ caused a slight, but not significant, increase in CD and CT levels; however, in the case of MDA, no increase was found in the liver. Glutathione redox system was activated in the liver by AFB₁, but less markedly by STC/PSTC. PSTC and AFB₁ resulted in a higher expression of GPX4, while GSS expression was down-regulated by AFB₁ on day 1, but up-regulated by STC on day 2 and by both mycotoxins on day 7. However, on day 14, GSS expression was down-regulated by PSTC. Expression of GSR was low on day 1 in AFB₁ and PSTC groups, but later it was up-regulated by AFB₁. The observed changes regarding gene expression strengthen the hypothesis that the mild oxidative stress, caused by the applied STC doses, activates the glutathione redox system of broiler chickens.

The usage of bottled water dispensers (BWDs) has spread worldwide. Despite their popularity, few studies have dealt with their microbial contaminants, and little attention is given to their fungal contamination. To our knowledge this is the first mycological study of BWDs in Europe. 36 devices have been examined in Budapest, Hungary. Despite of the strictly regulated water hygiene system in Hungary, molds and yeasts were detected in 86.8% of the samples, 56.76% were highly contaminated. Elevated heterotrophic plate counts were also observed in all samples compared to that of Hungarian drinking water. As all physical and chemical water quality characteristics have met the relevant national and European parametric values and neither totally explained the results of microbial counts, the effect of usage and maintenance habits of the devices were examined. Fungal concentrations were affected by the time elapsed since disinfection, days remaining until expiration of bottles, month of sampling and exposure to sunlight during storage. Microbes are able to proliferate in the bottled water and disperse inside the BWDs. Many of the detected fungal species (Sarocladium kiliense, Acremonium sclerotigenum/egyptiacum, Exophiala jeanselmei var. lecanii-corni, Exophiala equina, Meyerozyma guilliermondii, Cystobasidium slooffiae, Aspergillus jensenii, Bisifusarium biseptatum) are opportunistic pathogens for subpopulations of sensitive age groups and patients with immunodeficient conditions, including cystic fibrosis. Thus BWDs may pose a health risk to visitors of healthcare institutions, especially to patients with oral lesions in dental surgeries. The study draws attention to the need to investigate microbial contamination of these devices in other countries as well.

Vineyard floor management has been widely discussed for many decades, but it is still unclear how its intensity levels change the fungal community structure of grape rhizosphere. Our objective was to examine the density and rate of the habitats of fungi in three vineyards that differ only in the methods of tillage procedure applied, namely intensive, extensive and none (abandoned). The hypothesis was that in the cases of lower intensity or no soil tillage, there would be a higher level of fungal diversity with a lower ratio of pathogen strains in grape rhizosphere. In the course of this research, it has been determined that the level of fungal colonization of roots is the highest in the extensively managed vineyard, unrelated to season (spring and summer). Four of the five fungal genera detectable in all of the three sampled vineyards are registered as opportunist grape pathogens, however the fifth one, Trichoderma, is commonly used in biological plant protection. The diversity of fungal communities in grape rhizosphere, in accordance with the expectations, was the lowest in the intensively cultivated and highest in the abandoned vineyard, and it was not affected by seasons. The proportion of opportunist plant pathogen groups was higher in the intensive variant than in the other two (less-intensive variants); therefore, it is possible to conclude that soil under similar conditions but disturbed by intensive tillage methods tends to exhibit lower suppressivity.

A 160-day-long preliminary laboratory scale MBR treatment study and the performance test of a new 480 m³/day capacity full scale plant for quality improvement of effluent from a bitumen plant off-gas scrubbing followed by dissolved air flotation were conducted. Two testing periods were distinguished during the laboratory study, specifically the first with 100 days SRT and the second with 50 days SRT. To evaluate the possibility of the organic matter removal enhancement at the end of each testing period powdered activated carbon (PAC) treatment was carried out. The COD and oil & grease removal efficiency of the well acclimated MBR sludge was greater than 90% and 98%, respectively. The COD content of the treated wastewater during the full scale performance test period was reduced below 100 mg·L⁻¹. To ensure an optimal treatment process, the organic loading rate should be kept in 1.5 – 3 kg COD m⁻³ d⁻¹ range. and optimal biomass concentration of 10-15 g·L⁻¹ should be ensured to reduce the cleaning frequency of the membrane ultrafilters. To avoid exceedance of compliance with respect to the discharge criteria, further treatment step(s) should be considered prior to any treated wastewater reuse.

Mycotoxin production by aflatoxin B1 (AFB1) -producing Aspergillus flavus Zt41 and sterigmatocystin (ST) -hyperproducer Aspergillus creber 2663 mold strains on corn and rice starch, both of high purity and nearly identical amylose-amylopectin composition, as the only source of carbon, was studied. Scanning electron microscopy revealed average starch particle sizes of 4.54 ± 0.635 µm and 10.9 ± 2.78 µm, corresponding to surface area to volume ratios of 127 1/µm for rice starch and 0.49 1/µm for corn starch. Thus, a 2.5-fold difference in particle size correlated to a larger, 259-fold difference in surface area. To allow starch, a water-absorbing powder, to be used as a sole food source for Aspergillus strains, a special glass bead system was applied. AFB1 production of A. flavus Zt41 was determined to be 437.6 ± 128.4 ng/g and 90.0 ± 44.8 ng/g on rice and corn starch, respectively, while corresponding ST production levels by A. creber 2663 were 72.8 ± 10.0 µg/g and 26.8 ± 11.6 µg/g, indicating 3–fivefold higher mycotoxin levels on rice starch than on corn starch as sole carbon and energy sources. Key points: • A glass bead system ensuring the flow of air when studying powders was developed. • AFB1 and ST production of A. flavus and A. creber on rice and corn starches were studied. • 3–fivefold higher mycotoxin levels on rice starch than on corn starch were detected.