Antioxidant and anti-inflammatory activities of the methanol extract from the bran of the colored wheat, 'Ariheuk'

Abstract

In vitro antioxidant and anti-inflammatory activities were investigated using a 70% acidic methanol extract of the colored wheat bran, 'Ariheuk.' Active metabolites were identified via metabolomic analysis using multivariate statistical comparisons. The 'Ariheuk' bran extract (ABE) contained a higher total anthocyanin content (0.19 mg C3G/g) than the general wheat bran extract (GBE) (0.01 mg C3G/g). ABE exhibited stronger antioxidant and anti-inflammatory activities than GBE. The mechanism underlying the anti-inflammatory effects of ABE was explored by assessing the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2) in RAW 264.7 cells stimulated with lipopolysaccharide (LPS). The crude ABE extract was also partially fractionated into three subfractions (ABE-F1, ABE-F2, and ABE-F3) using preparative liquid chromatography (Prep-LC) to identify the active metabolites. The total anthocyanin content was highest in ABE-F3 (1.91 ± 0.06 mg C3G/g). Among the subfractions, ABE-F2 exhibited the highest antioxidant and anti-inflammatory activities. Several distinct metabolites contributing to the activities of ABE-F2 were identified, including various cyanidin and peonidin derivatives and apigenin derivatives, such as corymboside and schaftoside.