Factors Affecting the Content of Ergosterol and Zearalenone in Selected Grass Species at the End of the Growing Season

The objective of the study was to assess the safety of forage prepared from selected grass species by means of the analysis of ergosterol and zearalenone. Graminaceous plants studied at the end of their growing season were Festulolium, Dactylis glomerata and Arrhenatherum elatius. Other indicators assessed were the content of ergosterol and zearalenone during the autumn and the intensity of grassland use in the summer season as related to the studied contents of metabolites. Grasslands were harvested either in October, November or December. The secondary metabolites were analyzed by means of high performance liquid chromatography. At the end of the growing season, the ergosterol content was the lowest in the Festulolium forage (110.04 mg kg-1), the highest contents were observed in the Dactylis glomerata and Arrhenatherum elatius forages (145.73 mg kg-1 and 139.55 mg kg-1, respectively). The safety of Festulolium was also corroborated by the low zearalenone content (0.357 mg kg-1). On the other hand, the high ergosterol content in Arrhenatherum elatius was combined with a high content of zearalenone (1.554 mg kg-1). Although Dactylis glomerata exhibited an ergosterol content comparable with that of Arrhenatherum elatius forage, its zearalenone content was comparable to the Festulolium forage. Among the three species under study we found a significant difference (P P -1). The higher (P -1) was caused by the Arrhenatherum elatius forage. Moreover, the contents of ergosterol and zearalenone were affected (P < 0.01) also by the number of cuts in summer. The higher ergosterol content indicated a higher forage infestation by fungi and the inherent risk of the occurrence of mycotoxins. However, the high ergosterol content not always correlated with the high content of zearalenone. When cattle is grazing in winter, a higher occurrence of mycotoxins in the feed may be expected and the related damage to animal metabolism may increase the number of diseased animals with consequent impact on animal production, performance and health and animal husbandry economics

Forage as a Primary Source of Mycotoxins in Animal Diets

The issue of moulds and, thus, contamination with mycotoxins is very topical, particularly in connexion with forages from grass stands used at the end of the growing season. Deoxynivalenol (DON), zearalenone (ZEA), fumonisins (FUM) and aflatoxins (AFL) are among the most common mycotoxins. The aim of the paper was to determine concentrations of mycotoxins in selected grasses (Lolium perenne, Festulolium pabulare, Festulolium braunii) and their mixtures with Festuca rubra an/or Poa pratensis during the growing season as a marker of grass safety, which was assessed according to content of the aforementioned mycotoxins. During the growing season grass forage was contaminated with mycotoxins, most of all by DON and ZEA. The contents of AFL and FUM were zero or below the limit of quantification. Moreover, the level of the occurrence of mould was quantified as ergosterol content, which was higher at the specific date of cut. All results were statistically processed and significant changes were discussed

Design, synthesis and in vitro evaluation of benzothiazole-based ureas as potential ABAD/17β-HSD10 modulators for Alzheimer’s disease treatment

This work was supported by the Ministry of Health of the Czech Republic (no. NV15-28967A), Charles University in Prague (no. GAUK B-CH/992214, SVV 260 291) and the Alzheimer’s Society (specifically The Barcopel Foundation). This research is part-funded by the MSD Scottish Life Sciences fund.Amyloid-beta peptide (Aβ) has been recognized to interact with numerous proteins, which may lead to pathological changes in cell metabolism of Alzheimer’s disease (AD) patients. One such known metabolic enzyme is mitochondrial amyloid-binding alcohol dehydrogenase (ABAD), also known as 17β-hydroxysteroid dehydrogenase type 10 (17β-HSD10). Altered enzyme function caused by the Aβ-ABAD interaction, was previously shown to cause mitochondrial distress and a consequent cytotoxic effect, therefore providing a feasible target in AD drug development. Based on previous frentizole derivatives studies, we report two novel series of benzothiazolyl ureas along with novel insights into the structure and activity relationships for inhibition of ABAD. Two compounds ( 37 , 39 ) were identified as potent ABAD inhibitors, where compound 39 exhibited comparable cytotoxicity with the frentizole standard; however, one-fold higher cytotoxicity than the parent riluzole standard. The calculated and experimental physical chemical properties of the most potent compounds showed promising features for blood-brain barrier penetration.PostprintPeer reviewe

Application of near infrared spectroscopy to estimate selected free amino acids and soluble nitrogen during cheese ripening

This paper deals with the estimation of tyrosine, tryptophan and soluble nitrogen in 288 samples of the Edam cheese using the Near Infrared Spectroscopy. For analyses, the apparatus NIR Nicolet Antaris was used working in the regime of reflectance (i.e. using an integrating sphere) in combination with fibre optics (i.e. using a probe). For calibration, reference data from the UV spectrophotometer was used. Calibration models were developed using a PLS algorithm (least square method) and tested by means of cross-validation. Correlation coefficients: R = 0.911, R = 0.929 and R = 0.959 for soluble nitrogen, tryptophan and tyrosine, respectively, were achieved during measuring in the integrating sphere; R = 0.807, R = 0.945, R = 0.928 were achieved for soluble nitrogen, tryptophan and tyrosine, respectively, during measuring by probe. The results of the study show that NIR technology is suitable for fast and approximate determination of the level of cheese ripening. This can be used for the evaluation of the material for the processed cheese production, or cheese sale in optimal level of ripening

Maize ear rot, Fusarium mycotoxins and ergosterol content in maize hybrids

A field experiment with 26 maize hybrids including two genetically modified (Bt-transformation) ones and their non-transgenic counterparts was aimed to observe infection by maize car rot caused by Fusarium species and infestation by European corn borer. After harvest, the content of mycotoxins (deoxynivalenol, zearalenone, fumonisins) and ergosterol was determined. Climatic conditions of the harvest year 2007 were not favourable for the development of maize ear rot and the mycotoxin content was low. The ergosterol content was significantly correlated with disease extent and severity but there was no significant relationship between maize car rot and mycotoxins content. A significant relationship was found between zearalenone and European corn borer infestation. The content of mycotoxins; in Bt-hybrids was always lower than the mean of all hybrids. None of the tested Bt-hybrids was infested by European corn borer

Two Step Synthesis of a Non-symmetric Acetylcholinesterase Reactivator

The newly developed and very promising acetylcholinesterase reactivator (E)-1- (2-hydroxyiminomethylpyridinium)-4-(4-hydroxyiminomethylpyridinium)-but-2-ene dibromide was prepared using two different pathways via a two-step synthesis involving the appropriate (E)-1-(4-bromobut-2-enyl)-2- or 4-hydroxyiminomethyl-pyridinium bromides. Afterwards, purities and yields of the desired product prepared by both routes were compared. Finally, its potency to reactivate several nerve agent-inhibited acetylcholinesterases was tested

Preparation of laser induced periodic surface structures (LIPSS) and their transfer into sensing elements

Semiconducting metal oxides are widely used for solar cells, poto-catalysis, bio-active materials and gas sensors. Besides the material properties of the used semiconductor,the specific surface topology of the sensor determines the device performance. We investigate the preparation and transfer suitable metals onto LIPPS structures on glass for gas sensing applications