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Foot rot and crown rot are fungal diseases of wheat caused by a complex of Fusarium species. They have a huge economic impact mainly due to yield reduction. A survey was conducted to identify four Fusarium species, occurring on wheat stem bases, using speciesspecific PCR assays in samples collected during spring of 2012. The dominant species was F. graminearum, which was identified in above 64 % of samples. F. culmorum was detected in 15.71 %, F. poae in 15.71 % and F. sporotrichioides in 5.71 % wheat fields. Most of the wheat fields in the eastern Poland were infected with at least one or two of Fusarium species, while in central Poland no Fusarium species were identified in most of the fields. The presence of F. graminearum tends to favor the presence of F. culmorum and this effect was visible also for F. poae and F. sporotrichioides. The frequency of F. graminearum and F. culmorum detections were highest where wheat crops were preceded by maize and in the samples from late sown fields. The opposite observation was made for F. poae and F. sporotrichioides, where the number of detections of these species was higher in samples from early sown fields. The number of detected Fusarium species was significantly lower in samples collected from fields protected with autumn herbicide in comparison to unprotected fields. The rate of autumn N fertilization did not affect the number of Fusarium detections.

The genus Fusarium is considered to be one of the most pathogenic, phytotoxic and toxin-producing group of microorganisms in the world. Plants infected by these fungi are characterized by a reduced consumer and commercial value, mainly due to the contamination of crops with mycotoxins. Therefore, effective methods of reducing fungi of the genus Fusarium must be implemented already in the field before harvesting, especially with alternative methods to pesticides such as biocontrol. In this study we identified yeasts that inhibit the growth of the pathogenic fungi Fusarium culmorum, F. graminearum and F. poae. Tested yeasts came from different culture collections, or were obtained from organic and conventional cereals. The greater number of yeast isolates from organic cereals showed antagonistic activity against fungi of the genus Fusarium compared to isolates from the conventional cultivation system. Cryptococcus carnescens (E22) isolated from organic wheat was the only isolate that limited the mycelial growth of all three tested fungi and was the best antagonist against F. poae. Selected yeasts showed various mechanisms of action against fungi, including competition for nutrients and space, production of volatile metabolites, reduction of spore germination, production of siderophores or production of extracellular lytic enzymes: chitinase and β-1,3-glucanase. Of all the investigated mechanisms of yeast antagonism against Fusarium, competition for nutrients and the ability to inhibit spore germination prevailed.

Mycotoxins have a proven toxic effect on the health of humans and animals. Nowadays, there is a focus on having a healthy lifestyle and consuming organic foods. High quality grain products, especially spelt products, which are an important element of a well-balanced diet have become more popular. The aim of this study was to determine the mycotoxin content in spelt products available on the Polish market. Spelt products were collected in 2009 and 2010 in eastern Poland. The Enzyme-Linked ImmunoSorbent Assay (ELISA) method was used to identify aflatoxins, ochratoxin A, T-2 toxin, deoxynivalenol, and zearalenone. The study confirmed that all investigated mycotoxins were present in spelt products.

Mycotoxins, toxic secondary metabolites produced by fungi, are important contaminants in food and agricultural industries around the world. These toxins have a multidirectional toxic effect on living organisms, causing damage to the kidneys and liver, and disrupting the functions of the digestive tract and the immune system. In recent years, much attention has been paid to the biological control of pathogens and the mycotoxins they produce. In this study, selected yeasts were used to reduce the occurrence of deoxynivalenol (DON), nivalenol (NIV), and zearalenone (ZEA) produced by Fusarium culmorum, F. graminearum, and F. poae on wheat grain and bread. In a laboratory experiment, an effective reduction in the content of DON, NIV, and ZEA was observed in bread prepared by baking with the addition of an inoculum of the test yeast, ranging from 16.4% to 33.4%, 18.5% to 36.2% and 14.3% to 35.4%, respectively. These results indicate that the selected yeast isolates can be used in practice as efficient mycotoxin decontamination agents in the food industry.

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In this study, an optimised high hydrostatic pressure process (600 MPa, 15 min, 55 and 65 °C) caused elimination of microbial levels in beetroot/carrot juice (80:20 v/v, pH 4.0) after 28 days of storage (4 °C) (psychrotrophic bacteria, yeast and mould counts below the limit of detection = 0 log cfu mL À1 ). Room temperature (20 °C) was insufficient for the complete elimination of psychrotrophic bacteria (0.9-2.0 log cfu mL À1 after 7-28 days of storage). No significant (P < 0.05) changes in the polyphenol content were observed (1.11 AE 0.13 in control vs. 1.13 AE 0.13 mg gallic acid mL À1 in samples treated at 65 °C). No significant (P < 0.05) changes in the antioxidant, antiradical activity and biological properties of the highpressure processing (HPP)-treated juice were observed in the studies involving CCD 841 CoTr and HT29 cell lines. The HPLC-MS analysis confirmed increase in isobetalain, decarboxybetalain and betalain content (by 100%, 14% and 10%) and loss of vulgaxanthin I (by 65%) after HPP at 65 °C. The innovative character of this paper stems from the comprehensive quality assessment (especially experiments involving cell lines) of high-quality, safe beetroot-carrot juice that retains a major part of its bioactive compounds.