Carotenoid, Tocopherol, Phenolic Acid, and Antioxidant Properties of Maryland-Grown Soft Wheat

Abstract

Consumers' desires to either reduce the risk of or manage a specific health condition through improved diet have stimulated the research of agricultural products for their potential health beneficial components such as tocopherols and natural antioxidants. Soft wheat is one of the major crops in Maryland, with little information available about its potentially beneficial components. This study examined eight selected Maryland-grown soft wheat varieties or experimental lines for their potential beneficial components including tocopherols, carotenoids, total phenolics and phenolic acids and their antioxidant properties, including Fe(2+) chelating capacity and free radical scavenging activities against 2,2-diphenyl-1-picrylhydrazyl radical (DPPH(*) ), radical cation ABTS(*)(+), and oxygen radical (ORAC). The results showed that all tested soft wheat grain samples contained alpha-tocopherol, with a range of 3.4-10.1 microg/g. Lutein was the primary carotenoid present in the grain samples at a level of 0.82-1.14 microg/g, along with significant amounts of zeaxanthin and beta-carotene. Vanillic, syringic, p-coumaric, and ferulic acids were found in soluble free, soluble conjugated, and insoluble bound forms in the grain extracts, with ferulic acid as the predominant phenolic acid. The eight soft wheat varieties differed in their antioxidant properties. The tested wheat grain samples exhibited ED(50) values against DPPH(*) of 23-27 mg of grain equiv/mL, ORAC of 32.9-48 micromol of Trolox equiv (TE)/g, and ABTS(*)(+) scavenging capacity of 14.3-17.6 micromol of TE/g. These data suggest the possibility of producing soft wheat varieties rich in selected health beneficial factors for optimum human nutrition though breeding programs.

Distribution of Phenolic Acids and Antioxidant Activities of Different Bran Fractions from Three Pigmented Wheat Varieties

“…It can detect numerous samples in a short period and is sensitive enough to measure active constituents at low contents [32]. The DPPH radical scavenging property of each wheat bran sample was reported as the percent of DPPH radical scavenging, with a lower value of percent of DPPH scavenging associated with a stronger DPPH scavenging ability [33]. Figure 1 showed the percentage of DPPH radical scavenging of the free and bound phenolics in the bran fractions.…”

Hulless Barley – A Rediscovered Source for Functional Foods Phytochemical Profile and Soluble Dietary Fibre Content in Naked Barley Varieties and Their Antioxidant Properties

“…The TEAC assay was analysed following a modified method of Pellegrini et al (2003) and Moore et al (2005). A stable stock solution of ABTS radical cation was produced by reacting a 7 mmol L -1 aqueous solution of ABTS with 2.45 mmol L -1 potassium persulfate (final concentration) and allowing the mixture to stand in the dark at room temperature for 12 -16 h before use.…”

Whole Grain Consumption and Health of the Lower Gastrointestinal Tract: A Focus on Insoluble-Bound Phenolic Compounds

“…The total phenolic content and phenolic acid composition of eight Maryland-grown varieties of soft wheat was determined using an RP-HPLC-DAD method (Moore et al, 2005 Table 2. The total phenolic content and phenolic acid content of the insoluble-bound fraction of whole grains.…”

“…The antioxidant activity of eight Maryland-grown varieties of soft wheat was assessed using the ORAC and TEAC assay (Moore et al, 2005). When using the TEAC assay, antioxidant activities ranged from 14.3 to 17.6 μmol of Trolox equivalents/g of soft wheat grains.…”