**5. Conclusions**

The yellowish color after alcohol extraction of teff flour can be an evidence for the presence of phenolic compounds and flavonoids, and some of the main compounds that give brown teff seed its color are alkaline soluble and are probably insoluble condensed tannins. Regarding nutritional qualities, Teff has superior essential amino acid content and balance compared to wheat, rice, barely and maize, with the brown seed having higher amino acid content than the brown. The addition of reducing agents to extraction solvents enhances prolamin yield during teff protein fractionation. Tert-butanol is more efficient than ethanol for extraction of teff prolamins. Glutelin is a major protein in teff seeds. The extracted glutelin content of white teff is significantly higher than that of brown teff. SDS-PAGE analysis can reveal genetic variability storage proteins among white and brown teff.

**Author Contributions:** Y.A.G. performed most of experiments and played a major role in preparing the manuscript; J.H.-I. ran instruments for sample preparation and helped data analysis in this study; K.Y.-S., K.M.-K. and K.K.-P. provided their expertise in designing the experiments, analyzing the data and preparing the manuscript.

**Acknowledgments:** In The first author gratefully acknowledges the support from National Institute for International Education Development (NIIED) for funding his study under the Korean Government Scholarship Program (KGSP) scheme.

**Conflicts of Interest:** The authors declare no conflict of interest.

#### **References**


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