Q-TOF LC/MS identification and UHPLC-Online ABTS antioxidant activity guided mapping of barley polyphenols. (15th November 2018)

• Record Type: Journal Article
• Authors: Rao, Shiwangni; Santhakumar, Abishek B.; Chinkwo, Kenneth A.; Blanchard, Christopher L.
• Is Part Of: Food chemistry. Volume 266(2018)
• Page Start: 323
• Page End: 328
• Publication Date: 2018-11-15
• Subjects: ABTS 2, 2′-Azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) -- CE 2, 4, 6-catechin equivalents -- DPPH 2, 2-diphenyl-1-picrylhydrazyl -- FRAP ferric reducing ability of plasma assay -- GAE gallic acid equivalents -- ROS reactive oxygen species -- TAC total anthocyanin content -- TE Trolox equivalents -- TPC total phenolic content -- TPAC total proanthocyanidin content -- TPTZ Tris(2-pyridyl)-s-triazine -- Q-TOF LC/MS quad time of flight liquid chromatography mass spectra -- UHPLC ultra-high performance liquid chromatography; Barley -- UHPLC-online ABTS -- Antioxidant -- Cereals -- Q-TOF LC/MS; Caffeic acid (PubChem CID:689043) -- Catechin (PubChem CID:9064) -- Ellagic acid (PubChem CID:5281855) -- Ferulic acid (PubChem CID:445858) -- Gallic acid (PubChem CID:370) -- Isoscoparin-2″-O-glucoside (PubChem CID:72193659) -- P-coumaric acid (PubChem CID:637542) -- Procyanidin B2 (PubChem CID:122738) -- Prodelphinidin B (PubChem CID:5089687) -- Prodelphinidin B3 (PubChem CID:13831063); Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2018.06.011
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: Polyphenol content of eight Australian-grown barley varieties were characterised. Antioxidant activity of polyphenols was identified using UHPLC-online ABTS system. Phenolic composition and antioxidant activity exhibited significant variation. Variety Hindmarsh had higher polyphenolic content and antioxidant activity. Prodelphinidin B3 had the highest abundance and antioxidant activity. Abstract: The polyphenol composition and antioxidant activity of seven Australian-grown barley varieties were characterized in this study. UHPLC with an online ABTS system was used to identify individual polyphenols while simultaneously measuring their antioxidant activity. The Q-TOF LC/MS system was utilized to identify the phenolic compounds that demonstrated substantial antioxidant activity. The variety, Hindmarsh, showed the highest total phenolic content and antioxidant activity. There was no significant difference observed amongst the other varieties in their total phenolic content, however, they did have significant variation in proanthocyanidin content and antioxidant activity (p < 0.05). Prodelphinidin B3 was the most abundant polyphenol with the highest antioxidant activity amongst all the barley varieties tested. Other polyphenols identified with antioxidant activity included procyanidin, glycosides of catechin and flavan-3-ols. Polyphenol characterization of Australian grown barley varieties demonstrated that they have significant antioxidant activity, hence, promoting the value of whole grain barley as a potential functional food ingredient.