Chemical profiling and cytotoxic activity of aqueous extract of Veronica peduncularis M.Bieb.: A chemotaxonomical approach

Background and Aims: Genus Veronica (Plantaginaceae) is represented by 79 species in Turkish flora, 26 of which are endemic. Veronica species have a variety of uses including diuretic, anticancer, and rheumatic pains, wounds, and respiratory problems. According to phytochemical studies, Veronica species contain predominantly iridoid glucosides with some phenylethanoid and flavonoid glycosides. Methods: The aqueous extract of Veronica peduncularis M.Bieb. was tested for its cytotoxic activity on human rhabdomyosarcoma (RD) and human epidermoid carcinoma (HEp-2) cell lines using the MTT method. Chemical profile of the extract was determined by HPLC-DAD, and isolation studies were conducted. Results: The extract was found to show concentration-dependent cytotoxicity against tested cell lines. In addition, a comparison of the iridoid fraction of Veronica peduncularis with previously isolated iridoid glucosides on the HPLC-DAD system, showed the presence of aucubin, amphicoside, veratroyl catalpol, and veronicoside in this fraction. On the other hand, isolation and structure elucidation of plantamajoside and 4'-O-methylisoscutellarein-7-O-2''-O-(6'''-O-acetyl-[beta]-D-allopyranosyl)-[beta]-D-glucopyranoside from the phenolic fractions were performed by serial chromatographic and spectroscopic methods. Conclusion: To the best of our knowledge, this is the first cytotoxic activity and phytochemical study on the titled plant. The presence of iridoid glucosides and 8-hydroxyflavone glycosides is important for the chemotaxonomy of the genus Veronica. Keywords: 4'-O-methylisoscutellarein-7-O-2''-O-(6'''-O-acetyl-[beta]-D-allopyranosyl)-[beta]-D-glucopyranoside, HPLC, iridoid glucosides, phenolics, plantamajoside, Veronica