Corn cob and corn silk-based ingredients possess bioaccessible and antioxidant phenolic compounds displaying anti-inflammatory effects in vitro†

Abstract

The poor disposal and lack of utilization of corn cob (CC) and corn silk (CS) generate environmental problems. This research aimed to develop CC and CS-based ingredients (1 : 1, 1 : 2, and 2 : 1 mixtures) and evaluate the in vitro gastrointestinal bioaccessibility of selected polyphenols and their anti-inflammatory effect. (+)-Catechin, gallic acid, and p-coumaric acid were detected (HPLC-DAD) at all digestion stages and are the major contributors to the observed antioxidant and anti-inflammatory effects in vitro. Compounds from the digestible fractions of the ingredients contributed to up to 60% of membrane stability in vitro in human red blood cells, compared to Diclofenac® (82%). (+)-Catechin was the compound exhibiting the highest anti-inflammatory effect in silico against anti- and pro-inflammatory PGE2, PPARγ, and COX-2 proteins at two model pH levels of membrane stability (5.7 and 7.0). Results suggested that polyphenols from agricultural residues (CC and CS) manufactured as ingredients are bioaccessible and exhibit potential biological effects, and could be used as potential feasible food ingredients.