Abstract

• The Smallanthus sonchifolius (yacon) tubers were dried at the ambient temperature, chopped into bits and percolated with70% ethanol. Qualitative phytochemical screening was determined by the standard procedure suggested the presence of alkaloids, flavonoids, steroids, polyphenols, terpenoids,-amino acids, glycosides, phenolic compounds, carbohydrate, saponins, tannins, protein, and reducing sugars. Starch and cyanogenic glycosides were not detected in yacon tubers. The profile of the chemical constituents present was established by thin layer chromatography. Six pure organic constituents namely, stigmasteryl acetate (0.003%), β-sitosteryl acetate (0.005%), hexadecanoic acid (0.009%), β-sitosterol (0.02%), chlorogenic acid (0.12%) and β-sitosterol β-D-glucoside (0.8%) based on ethyl acetate extract were isolated from the ethyl acetate soluble fraction of the 70% ethanol extract of the yacon tuber on a silica gel column by gradient elution with petroleum and ethyl acetate (PE-EA, 99:1 to EA only). The isolated compounds were characterized by UV and FTIR.