Extraction and Identification of Antioxidants in the Roots of Yacon (Smallanthus sonchifolius)

Abstract
Yacon, Smallanthussonchifolius (Poepp. & Endl.) H. Robinson, Asteraceae, an important economic species grown for its juicy tuberous root, is potentially beneficial in the diet to diabetics. The antioxidative activity of yacon root was studied by 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. Antioxidants were extracted by methanol and isolated and purified by gel permeation chromatography and preparative reverse-phase HPLC. Two of the major antioxidants were identified as chlorogenic acid and tryptophan by NMR and mass spectrometry. Keywords: Yacon; Smallanthussonchifolius; antioxidant; chlorogenic acid; tryptophan; Asteraceae