Studies on the chemical constituents of the anti-osteoporotic part of Lepidium meyenii Walp. produced in Heqing

This study was designed to investigate the chemical constituents of the anti-osteoporotic part of Lepidium meyenii Walp. (maca) produced in Heqing, Yunnan. Seven compounds were isolated from the n-BuOH extract of maca using combination of column chromatographies on MCI resin, silica gel, C₁₈ bonded silica gel, and Sephadex LH-20, followed by semi-preparative HPLC and recrystallization. The purified compounds were identified on the basis of their physicochemical properties and spectral data as macaolidine (1), tryptophan (2), daucosterol (3), (3S)-1,2,3,4-tetrahydro-β-carboline-3-carboxylicacid (4), chlorogenic acid (5), luteolin (6), and hyperoside (7). Compound 1 is a new phenylacetamide alkaloid, and compounds 4-7 were isolated from Lepidium meyenii for the first time.