Three hard winter wheat varieties (Akron, Trego, and Platte) were examined and compared for their free radical scavenging properties and total phenolic contents (TPC) Free radical scavenging properties of wheat grain extracts were evaluated by spectrophotometric and electron spin resonance (ESR) spectrometry methods against stable 2,2-diphenyl-1-picryhydrazyl radical (DPPH*) and radical cation ABTS*+ (2,2'-azino-di[3-ethylbenzthiazoline sulfonate]) The results showed that the three wheat extracts differed in their capacities to quench or inhibit DPPH* and ABTS*+ Akron showed the greatest activity to quench DPPH radicals, while Platte had the highest capacity against ABTS*+ The ED50 values of wheat extracts against DPPH radicals were 060 mg/mL for Akron, 71 mg/mL for Trego, and 095 mg/mL for Platte under the experimental conditions The trolox equivalents against ABTS*+ were 131 +/- 044, 108 +/- 005, and 191 +/- 006 micromol/g of grain for Akron, Trego, and Platte wheat, respectively ESR results confirmed that wheat extracts directly reacted with and quenched free radicals The TPC were 4879 +/- 9278 microg gallic acid equivalents/g of grain No correlation was observed between TPC and radical scavenging capacities for DPPH* and ABTS*+ (p = 015 and p > 05, respectively)

Free radical scavenging properties of wheat extracts.

Specialty sorghums, their brans, and baked and extruded products were analyzed for antioxidant activity using three methods:  oxygen radical absorbance capacity (ORAC), 2,2‘-azinobis (3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS), and 2,2-diphenyl-1-picrylhydrazyl (DPPH). All sorghum samples were also analyzed for phenolic contents. Both ABTS and DPPH correlated highly with ORAC (R2 = 0.99 and 0.97, respectively, n = 18). Phenol contents of the sorghums correlated highly with their antioxidant activity measured by the three methods (R2 ≥ 0.96). The ABTS and DPPH methods, which are more cost effective and simpler, were demonstrated to have similar predictive power as ORAC on sorghum antioxidant activity. There is a need to standardize these methods to allow for data comparisons across laboratories. Keywords: Sorghum; antioxidant; phenols; ORAC; ABTS; DPPH

Screening Methods To Measure Antioxidant Activity of Sorghum (Sorghum bicolor) and Sorghum Products

http://users.atw.hu/koles/koles/eload/kiss/Sorghum_and_millet_phenols_and_antioxidants_(2006).pdf

Sorghum and millet phenols and antioxidants

The growing public awareness of nutrition and health care research substantiates the potential of phytochemicals such as polyphenols and dietary fiber on their health beneficial properties. Hence, there is in need to identify newer sources of neutraceuticals and other natural and nutritional materials with the desirable functional characteristics. Finger millet (Eleusine coracana), one of the minor cereals, is known for several health benefits and some of the health benefits are attributed to its polyphenol and dietary fiber contents. It is an important staple food in India for people of low income groups. Nutritionally, its importance is well recognised because of its high content of calcium (0.38%), dietary fiber (18%) and phenolic compounds (0.3–3%). They are also recognized for their health beneficial effects, such as anti-diabetic, anti-tumerogenic, atherosclerogenic effects, antioxidant and antimicrobial properties. This review deals with the nature of polyphenols and dietary fiber of finger millet and their role with respect to the health benefits associated with millet.

/pdf/health-benefits-of-finger-millet-eleusine-coracana-l-1cwx277o1c.pdf

Health benefits of finger millet (Eleusine coracana L.) polyphenols and dietary fiber: a review

Soluble and insoluble-bound phenolic extracts of several varieties of millet (kodo, finger, foxtail, proso, pearl, and little millets) whole grains were evaluated for their phenolic contents and antioxidative efficacy using trolox equivalent antioxidant capacity (TEAC), reducing power (RP), and beta-carotene-linoleate model system as well as ferrous chelating activity. In addition, ferulic and p-coumaric acids were present in soluble and bound phenolic fractions of millets, and their contents were determined using high-performance liquid chromatography (HPLC) and HPLC-mass spectrometry (MS). Kodo millet had the highest total phenolic content, whereas proso millet possessed the least. All millet varieties showed high antioxidant activities, although the order of their efficacy was assay dependent. HPLC analysis of millet phenolic extracts demonstrated that the bound fractions contained more ferulic and p-coumaric acids compared to their soluble counterparts. The results of this study showed that soluble as well as bound fractions of millet grains are rich sources of phenolic compounds with antioxidant, metal chelating, and reducing power. The potential of whole millets as natural sources of antioxidants depends on the variety used. The importance of the insoluble bound fraction of millet as a source of ferulic acid and p-coumaric acid was established, and their contribution to the total phenolic content must be taken into account in the assessment of the antioxidant activity of millets.

V.S. Murty

Papers

ESR spectroscopic studies on free radical quenching action of finger millet (Eleusine coracana)