Purification, identification, and characterization of two benzophenanthridine alkaloids from Corydalis longicalcarata rhizomes with anti-mitotic and polyploidy-inducing activities

Mitosis has long been a therapeutic target for the treatment of cancer. After conducting a phenotypic screen for anti-mitotic activity in a crude extract library of more than 2000 medicinal plants, we identified the rhizomes of Corydalis longicalcarata. Guided by the bioactivity-based assay, two benzophenanthridine alkaloids were purified and subsequently identified as corynoline and its close analog acetylcorynoline. This study uncovers a previously unknown antimitotic activity for these two phytochemicals, discovers their potential to be developed as anticancer drugs, and highlights their pleiotropic effects on cell division, including prevention of chromosome congression, compromise of spindle checkpoint response, and blockage of cytokinesis.