Nutrition is a source of energy, and building material for the human organism. The quality of food has an effect on the quality of individual life. Minerals and vitamins participate in various catalytic and regulatory functions of the main metabolic processes: absorption, transport, redox and biosynthesis of organic compounds, genetic information transfer, etc. Regular consumption of dietary fibers like β-glucans and oat-specific phenolics, antioxidants, and avenanthramides, stimulate innate and acquired immunity, prevent cancer, obesity, reduce glucose, total cholesterol and triglyceride blood levels and regulate the expression of cholesterol-related genes. Thus, all those compounds are vitally important for the normal functional status of the human body. A deficiency in one or another essential nutrient causes disruptions in human metabolism, thus leading to serious illnesses. Plants are the main source of essential nutrients that are bioavailable for humans. One of the most popular groups of staple crops are the small grains crops (SGC), so these crops are most often used for biofortification purposes. Exploiting the potential of plant resources, biofortification is a long-term strategy, aimed at increasing the number of essential micro- and macronutrients in major food sources and ensuring their bioavailability. The most productive way to implement such strategy is the active use of the possibilities offered by collections of plant genetic resources, including SGC, concentrated in various countries of the world. The collections of plant resources contain both cultivated plants and their wild relatives that possess the required composition of micro- and macronutrients. A complex scientific approach to studying plant germplasm collections, together with agricultural practices (soil enrichment with fertilizers with a required composition), genetic biofortification (traditional breeding, marker-assisted selection or genetic engineering tactics), and their combinations will lead to the development of new biofortified cultivars and improvement of old ones, which can be used to solve the problems of unbalanced nutrition (malnutrition or hidden hunger) in different regions of the world.

Flax is one of the oldest oil crops, but only since the end of the twentieth century nutritional use of its whole seeds and flour has been resumed. This crop has been evaluated for its oil fatty acid composition, content of sterols and tocopherols, carbohydrate composition of mucilage, but a comprehensive study has never been carried out, so the aim of the work was to identify differences in the metabolomic profiles of flax lines contrasting in color and size of seeds. The biochemical composition of seeds from 16 lines of the sixth generation of inbreeding was tested using gas chromatography coupled with mass spectrometry. In total, more than 90 compounds related to sugars (78% of the identified substances), free fatty acids (13%), polyatomic alcohols (5%), heterocyclic compounds, free amino acids, phytosterols and organic acids (no more than 2.5% in total) were identified. Statistical analyses revealed six main factors. The first is a factor of sugar content; the second one affects most of organic acids, as well as some free fatty acids, not related to reserve ones, the third factor is related to compounds that play a certain role in the formation of “storage” substances and resistance to stress, the fourth factor is influencing free polar amino acids, some organic and free fatty acids, the fifth one is a factor of phenolic compounds, the sixth factor combined substances not included in the first five groups. Factor analysis made it possible to differentiate all 16 lines, 10 of which occupied a separate position by one or two factors. Interestingly, the first two factors with the highest loads (20 and 15% of the total variability, respectively) showed a separate position of the gc-432 line, which differed from the others, not only by chemical composition, but also by the phenotype of the seeds, while gc-159 differed from the rest ones by the complex of organic acids and other substances taking about 1% of the extracted substances of the seed. Thus, the analysis of metabolomic profiles is promising for a comprehensive assessment of the VIR flax genetic collection, which has wide biochemical diversity.