Phenolic composition and antioxidant potential in Turkish einkorn, emmer, durum, and bread wheat grain and grass

•IZA (einkorn) wheatgrass had the highest amount of p-coumaric acid.•Kıraç-66 (bread wheat) grain had the highest amount of trans-ferulic acid.•The highest amount of p-coumaric and trans-ferulic acid was in IZA (einkorn) among the tested whatgrasses.•The amount of p-coumaric acid was higher in the wheatgrasses of the tested wheats than in their grains.•The amount of trans-ferulic acid was higher in the wheat grains than their wheatgrasses.•Emmer grain and einkorn wheatgrass had the strongest antioxidant activity. Wheat has been a primary food source in human and animal nutrition in many parts of the world since ancient times. The objective of the present study was to evaluate phenolic acid composition (p-coumaric acid, caffeic acid, trans-ferulic acid, and sinapic acid) and antioxidant potentials (total phenol and flavonoid contents, and free radical scavenging activity) in both grain and grass of einkorn (Triticum monococcum spp. monococcum; Cv. IZA), emmer (T. dicoccum ssp. dicoccum Schrank.) population, durum (T. durum Desf.; Cv. Kunduru-1149), and bread wheat (T. aestivum L.; Cv. Kıraç-66). The amount of phenolic acids in grain and two weeks old grass obtained from 4 different wheat species was detected by LC-ESI-MS/MS analysis. The p-coumaric acid was the most abundant compouns in all tested grasses, while trans-ferulic acid were the most abundant compounds in all tested grains. It was determined that einkorn (IZA) had the highest amount of p-coumaric acid (1.360 µg/g dw) and trans-ferulic acid (0.490 µg/g dw) among the grasses, while the highest p-coumaric acid (0.770 µg/g dw) and trans-ferulic acid (3.400 µg/g dw) were found in bread wheat (Kıraç-66) among the grains. The highest total phenolic content was obtained from grain (90.12 mg/g dw) and grass (99.24 mg/g dw) of durum wheat (Kunduru -1149). The the highest total flavonoid content was found in both grain (141.58 mg/g dw) and grass (179.50 mg/g dw) of einkorn (IZA). Grains of emmer (2.68 µg/mL) and grasses of einkorn wheat (2.98 µg/mL) had the strongest antioxidant activity with the lowest IC50 (concentration inhibiting 50% of DPPH) values. Einkorn, an ancestral wheat species with 14 chromosomes, has higher phenolic molecules, total flavonoid content and antioxidant potential than modern wheat species such as durum wheat with 28 chromosomes and bread wheat with 42 chromosomes. Wheatgrass of IZA (einkorn) is thought to have the potential as a functional food/beverage in the future with its high