Ergosterol (ERG) is a major sterol constituent of most fungi. Its concentration is negligible in higher plants, but can be used as a chemical marker of the presence of fungal contaminations. In this study, ERG concentration was assessed in randomly collected samples of naturally contaminated grain (wheat, barley and oat) and in samples of grain (wheat, barley, triticale and oat) harvested after inoculation of heads with conidia of different Fusarium species. Wheat samples were analysed at three stages of grain development. The lowest ERG concentration was found in non-inoculated samples at the first stage of grain development. This concentration was increasing with grain ripening. In naturally contaminated samples collected after harvest, ERG concentration was lower in wheat than in barley and oat. ERG concentrations in inoculated samples varied significantly, but were always significantly higher than in naturally contaminated samples. In the above cereal samples it was much lower than the levels assayed in laboratory cultures inoculated with fungi from genus Fusarium. The content of ERG was also analyzed in milling products of small-grained cereals and other foodstuffs, where a considerable variation was observed. The lowest ERG amounts were assayed in flours with a high degree of purification, while the highest ones in case of flours and products with a low purification rate. The results indicate the potential application of HPLC combined with microwave-assisted extraction both when assaying samples with low ERG concentrations (naturally contaminated) and those characterized with high contents of fungal biomass (strongly infected, artificially inoculated). It also facilitates analyses of fungal biomass in technological processes, where results may be expected to vary considerably.

To date, studies on volatile metabolites in cereal grain have focused mainly on a single species. In this paper, results are presented of the analysis of volatile compounds in five cereal grain species (spring wheat, durum wheat, triticale, rye, oats and barley) based on representative sampling of at least 15 cultivars of individual species. Profiles of volatile compounds were determined using solid phase microextraction (SPME) and GC-TOF (time of flight mass spectrometry). Many of the volatile compounds were only present in single samples; however, several dozen were found in over 50% of samples and 46 volatiles were found in all samples. Among them there were six alcohols, 10 aldehydes and ketones, six terpenes, seven hydrocarbons and 11 benzene derivatives. The highest concentrations of these compounds were found in durum wheat, while the lowest were observed in triticale and rye.

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In natural conditions cereals can be infested by pathogenic fungi. These can reduce the grain yield and quality by contamination with mycotoxins which are harmful for plants, animals, and humans. To date, performed studies of the compounds profile have allowed for the distinction of individual species of fungi. The aim of this study was to determine the profile of volatile compounds and trichothecenes of group B, ergosterol, adenosine triphosphate content carried out on a representative sample of 16 genotypes of related cereals: triticale, bread wheat, and durum wheat. Based on an analysis of volatile compounds by means of gas chromatography mass spectrometry and with the use of an electronic nose, volatile profiles for cereals were determined. Differentiation is presented at four levels through discriminant analysis, heatmaps, principal component analysis (PCA), and electronic nose maps. The statistical model was built by subsequent incorporation of chemical groups such as trichothecenes (GC/MS), fungal biomass indicators ergosterol (HPLC) and ATP (luminometric) and volatiles. The results of the discriminatory analyses showed that the volatile metabolites most markedly differentiated grain samples, among which were mainly: lilial, trichodiene, p-xylene. Electronic nose analysis made it possible to completely separate all the analyzed cereals based only on 100 ions from the 50–150 m/z range. The research carried out using chemometric analysis indicated significant differences in the volatile metabolites present in the grain of bread wheat, durum wheat and triticale. The end result of the performed analyses was a complete discrimination of the examined cereals based on the metabolites present in their grain.

Ergosterol (ERG) content, being an indicator of fungal biomass, was analyzed in samples of eggshell, egg white, and egg yolk from eggs from farms with intensive management systems of layer hens (i.e., cage and litter housing). Moreover, analogous samples were analyzed from eggs from farms in the western central part of Poland, where layer hens were kept in the organic system. In all samples, the highest ERG concentration was found in shells and the lowest in egg white, whereas ERG was not found in egg yolk. When comparing investigated housing systems, a higher concentration of the analyzed metabolite was detected in eggs from litter housing than in eggs from cage housing. Concentrations of ERG in samples of eggs from organic husbandry were highly varied, ranging from 2.44 to 42.67 mg/kg in shells and from 0.28 to 16.11 mg/kg in egg white.