Phytochemical Analysis of Phenolics, Sterols, and Terpenes in Colored Wheat Grains by Liquid Chromatography with Tandem Mass Spectrometry

Abstract

The colored grain of wheat (Triticum aestivum L.) contains a large number of polyphenolic compounds that are biologically active ingredients. The purpose of this work was a comparative metabolomic study of extracts from anthocyaninless (control), blue, and deep purple (referred to here as black) grains of seven genetically related wheat lines developed for the grain anthocyanin pigmentation trait. To identify target analytes in ethanol extracts, high-performance liquid chromatography was used in combination with Bruker Daltonics ion trap mass spectrometry. The results showed the presence of 125 biologically active compounds of a phenolic (85) and nonphenolic (40) nature in the grains of T. aestivum (seven lines). Among them, a number of phenolic compounds affiliated with anthocyanins, coumarins, dihydrochalcones, flavan-3-ols, flavanone, flavones, flavonols, hydroxybenzoic acids, hydroxycinnamic acids, isoflavone, lignans, other phenolic acids, stilbenes, and nonphenolic compounds affiliated with alkaloids, carboxylic acids, carotenoids, diterpenoids, essential amino acids, triterpenoids, sterols, nonessential amino acids, phytohormones, purines, and thromboxane receptor antagonists were found in T. aestivum grains for the first time. A comparative analysis of the diversity of the compounds revealed that the lines do not differ from each other in the proportion of phenolic (53.3% to 70.3% of the total number of identified compounds) and nonphenolic compounds (46.7% to 29.7%), but diversity of the compounds was significantly lower in grains of the control line. Even though the lines are genetically closely related and possess similar chemical profiles, some line-specific individual compounds were identified that constitute unique chemical fingerprints and allow to distinguish each line from the six others. Finally, the influence of the genotype on the chemical profiles of the wheat grains is discussed.

Grain color formation and analysis of correlated genes by metabolome and transcriptome in different wheat lines at maturity

“…This may be due to the transferred chromosomal segments of Thinopyrum ponticum in blue-grained wheats having a different length and position, resulting in great genetic diversity among individual blue grain genomes ( 8 ). The various studies above confirm previous findings or find contradictory results, which may be due in part to different genotypes and growing sites resulting in unique chemical characteristics and specific compounds for each anthocyanin-rich strain ( 38 ).…”

Quality, Nutritional Properties, and Glycemic Index of Colored Whole Wheat Breads

“…Bread wheat genotypes obtained from Omsk State Agrarian University (Russian) were used in the study. For the first time under conditions of Western Siberia, the variety EF 22 and line Element 22-PurplePF (8) with a purple grain color, as well as the bluegrained wheat line Element_22-Blue4Th (10) (Figure 1), were obtained by crossing variety Element 22 with an anthocyanin biosynthesis gene donor. Variety EF 22 and line Element 22-PurplePF (8) are sister lines that were obtained by individual selections from the hybrid combination Element 22 *2/i:S29PF.…”

“…The content of phytochemicals is generally limited in white- or red-grained wheat varieties while they occur more consistently in the so-called pigmented/colored varieties [ 7 ]. The colored wheat provides nutritional products with higher flavonoids (e.g., anthocyanin), phenolic acids, carotenoids, and other compounds with antioxidant activities that are primarily located in the pericarp and aleurone layers [ 8 , 9 , 10 ]. Owing to the presence of these compounds and dietary fibers, colored wheats exhibit antioxidant properties that basically help in protecting against degenerative diseases [ 11 ].…”

Advances of metabolomic in exploring phenolic compounds diversity in cereal and their health implications

“…Comparative metabolomic studies have shown that coloured‐grain wheat lines have significantly higher levels of various substances, including those in the carboxylic acid, sterol, anthocyanin, and flavone families, compared to unpigmented‐grain controls (Razgonova et al ., 2021). They stated 3–6 times increase in the level of constituents belonging to carboxylic acid family, 2–3 times from sterol family, 2–4 times from anthocyanin family, and 1.5–2.7 times from flavone family in comparison to the unpigmented‐grain.…”