Total phenolics and antioxidant capacity of the white and brown teff [Eragrostic tef (Zuccagni) trotter] varieties cultivated in different parts of Ethiopia

Abstract

ABSTRACT. This study was aimed to determine the total phenolics contents and antioxidant capacity of white and brown teff grain samples. The free total polyphenolic content (TPPC), bound TPPC and total flavonoids content ranged from 62.1–129.9, 84.6–189.6 mg GAE/100 g and 84.4–195.1 mg QE/100 g, respectively, in white teff samples, and, 118.6–196.7, 141.1–195.1 mg GAE/100 g and 97.8–202.5 mg QE/100 g, respectively, in brown teff samples. Besides, the free 2,2-diphenyl-1-picrylhydrazyl (DPPH) and bound DPPH ranged from 74.8–98.3, 77.1–99.9 mg AAE/100 g, respectively, for white teff samples, and, 68.7–93.1 and 71.2–99.4 mg AAE/100 g, respectively, for brown teff samples. This study revealed that total phenolics content was higher in brown teff samples than white teff samples and is in agreement with other reports. However, their DPPH scavenging activities were nearly equal, indicating that both varieties of teff are relevant for human nutrition and health. Furthermore, the dendrogram has shown sharp separation of the samples based on their origin and variety related to the total phenolics parameters. Hence, findings of this study can help consumers appreciate the nutritional value of white and brown teff grains; provide them guidance for teff purchase and production.

KEY WORDS: Teff, Phenolics, Gallic acid, Ascorbic acid, Anti-oxidant, DPPH

Bull. Chem. Soc. Ethiop. 2022, 36(4), 749-766.                                                             

DOI: https://dx.doi.org/10.4314/bcse.v36i4.3