To explore the dietary intake risk of deoxicallenol (DON) from barley subjected to different storage conditions or processing methods, barley was stored for different periods (180, 270 and 360 days) at different temperature (5, 15, 25 and 35 ℃) and relative humidities (55%, 65%, 75% and 85%). Another part of samples were processed by boiling, steaming or fermentation. DON content in all samples was detected by enzyme-linked immunosorbent assay (ELISA), and the risk of chronic and acute dietary intake of DON was explored by point and probability assessment. The results showed that the estimated daily intake (EDI) of DON from fresh barley was 0.00030 to 0.00130 mg/kg, and the chronic risk index was 0.30 to 1.31, which increased by up to 0.63 after 360 days of storage. The risk of dietary exposure to DON was 32.7%, the national estimated short-term intake (NESTI) was 0.0026 to 0.0055 mg/kg and the hazard quotient (HQ) for acute riskassessment was 0.33 to 0.69, indicating no acute exposure risk. After processing, the risk of chronic exposure decreased from 0.60–2.60 to 0.17–2.34, and the risk of acute exposure decreased by up to 0.64. After long-term storage, the level of exposure to DON from barley was high, causing a high health risk, which was effectively reduced after processing, and the exposure risk for children was more serious than that in adults, to which much attention should be paid.

This study was conducted in order to explore the effect of lead (Pb) stress on the nutritional value and flavor of barley seedling powder. Fourier transform infrared (FTIR) spectroscopy and targeted metabolomics based on liquid chromatography-mass spectrometry (LC-MS) were used for quantitative and qualitative analysis of protein secondary structure and amino acid contents in barley seedling powders with and without Pb stress during growth. The results showed that Pb stress led to the transformation of protein secondary structure in barley seedlings from disordered (β-turn and random coil) to ordered (α-helix) structure. Through high-throughput targeted metabolomic analysis, a total of 25 amino acids were identified and quantified in barley seedling powder. Pb stress decreased the contents of Arg, Pro and His, but increased the content of Val, which proves that Pb could reduce the nutritional value and sweetness, and increase the bitterness of barley seedling powder. These results provide some basic data for the development of barley-based health foods.

Auricularia auricula was selenized by adding exogenous selenium to the compost. The effect of selenization on the dynamic changes of metabolic pathways and metabolites in A. auricula was investigated using liquid chromatographymass spectrometry (LC-MS)-based metabolomics combined with different multivariate statistical analyses such as principal component analysis (PCA), partial least squares-discriminant analysis (PLS-DA), and hierarchical cluster analysis. Totally 669 metabolites were identified in A. auricula, inorganic selenized A. auricula grown on sodium selenite, and organic selenized A. auricula grown on selenium-rich corn straw. A total of 228 differential metabolites (DEMs) were obtained in A. auricula vs inorganic selenized A. auricula, and 267 DEMs in A. auricula vs organic selenized A. auricula. It was found that selenization had a great effect on the contents of organic acids and their derivatives, lipids and lipid-like molecules in A. auricula, and the effect of organic selenization was more pronounced. Kyoto Encyclopedia of Genes and Genomes (KEGG) metabolic pathway analysis found that selenization had a significant effect on lipid and amino acid metabolism. These results showed that lipid metabolism, amino acid metabolism and the biosynthesis of other secondary metabolites in A. auricula changed significantly after selenization, which had a significant effect on lipids, amino acids and other metabolites in A. auricula. This indicated that selenization affected the nutritional composition and flavor quality of A. auricula.