Cytotoxic Activity of Alkaloids Isolated from Stephania glandulifera Miers

Abstract From the caudex of Stephania glandulifera Miers, five alkaloids were isolated using a cold percolation method with 90% methanol. The methanol extract was fractionated into three different fractions from where the alkaloids were purified using preparative HPLC. Structure elucidations were performed by modern spectral analysis including Mass and 1D and 2D-NMR spectroscopy. The purified compounds were tested against the LN-229 human brain glioblastoma cell line by performing a Sulforhodamine B assay (SRB). The isolated compounds were confirmed to be tetrahydropalmatine (1), palmatine (2), stepharanine (3), stepholidine (4), and stepharine (5). Compound 5 showed anticancer activity in the LN-229 human brain glioblastoma cell line with an IC50 value of 8.1 μg/mL. In this study, five alkaloids belonging to three classes namely proaporphine, protoberberine, and tetrahydroprotoberberine were isolated for the first time from Stephania glandulifera Miers. Among them, stepharine showed anticancer activity in the LN-229 human brain glioblastoma cell line which can be further developed as a potential anticancer agent. GRAPHICAL ABSTRACT