Phenolic Acid Profiles and Antioxidant Activity of Major Cereal Crops
Department—Agrochemical Laboratory, Agricultural Institute Osijek, Južno predgrađe 17, 31000 Osijek, Croatia
Department of Plant Breeding and Small Cereal Crop Genetics, Agricultural Institute Osijek, Južno predgrađe 17, 31000 Osijek, Croatia
Department of Maize Breeding and Genetics, Agricultural Institute Osijek, Južno predgrađe 17, 31000 Osijek, Croatia
Department of Forage Plant Breeding and Genetics, Agricultural Institute Osijek, Južno predgrađe 17, 31000 Osijek, Croatia
Department of Seed Production and Processing, Agricultural Institute Osijek, Južno predgrađe 17, 31000 Osijek, Croatia
Author to whom correspondence should be addressed.
Antioxidants 2020, 9(6), 527; https://doi.org/10.3390/antiox9060527
Received: 26 May 2020 / Revised: 10 June 2020 / Accepted: 14 June 2020 / Published: 16 June 2020
(This article belongs to the Special Issue Phenolics as Antioxidant Agents)
Phenolic acids (PAs) are a dominant group of phenolic compounds in cereals, existing mostly bound to compounds of cell wall. In this study, a total of 25 cereal grain samples, including wheat, winter and spring barley, corn, and popcorn, were evaluated for bound PAs and antioxidant activity in a two-year field trial. The PA contents, determined by HPLC, were significantly affected by cereal type. The mean total PA content was highest in popcorn and corn (3298 and 2213 μg/gdm, respectively), followed by winter and spring barley (991 and 908 μg/gdm, respectively) and wheat (604 μg/gdm). Ferulic acid was the most abundant, accounting from 62% to 83% of total PAs (in popcorn and winter and spring barley, respectively). Across cereals, p-coumaric (35–259 μg/gdm) and p-hidroxybenzoic (45–79 μg/gdm) were also dominant, while in corn and popcorn o-coumaric (71 and 89 μg/gdm, respectively) also occurred in higher content. The mean total phenol content ranged from 853 μg GAE/gdm (wheat) to 1403 μg GAE/gdm (winter barley) with DPPH scavenging activity from 14% to 67%, respectively. A significant influence of crop years on the ferulic acid and total PA content was found, while the variability of other PAs was dependent on the cereal type. The results indicated a high health benefit potential of selected cereals.