Abstract

Aim/Background: Boraginaceae is famous for the production of PAs and some of these PAs are carcinogenic, and also cause liver failure. So the aim of present study was to identify the presence or absence of hepatotoxic pyrrolizidine alkaloids in the tribe Lithospermea (Boraginaceae). If any are found, it may indicate excluding members of this tribe from herbal formulation or from use on patients with liver problems.
Materials and Methods: Plant samples of Onosma hispida Wall. ex G. Don, Onosma paniculatum Bureau & Franch., Onosma hookeri var. longiflorum (Duthie) A.V. Duthie ex Stapf, and Maharanga emodi (Wall.) A. DC. from Boraginaceae—Tribe Lithospermeae were collected from various regions of Pan Himalaya and brought to Beijing Normal University for further experimentation. We used acetonitrile—water gradient with 0.1% formic acid as the mobile phase and Zorbax SB-Aq column, to analyze samples. Furthermore, we also searched the literature to find ethnomedicinal importance of these plants.
Results: The results showed that these plants are used orally for the treatment of various human ailments and so we further investigated these plants for toxic pyrrolizidine alkaloids (PAs). HPLC results showed that leaves of these plants were PA positive, and out of four PA standards, three: Heliotrine (2), Lycopsamine (3), and Echimidine (4) were detected.
Conclusions: In this study, we present a new report about the presence of toxic PAs in the leaves of Onosma hispida, O. paniculatum, Onosma hookeri var. longiflorum, and Maharanga emodi from the Pan-Himalaya region. These plants are used in traditional medicine mostly in Pakistan, Nepal, and China, and the presence of hepatotoxic PAs limit the use for medicinal purposes

Key words: Ethnomedicine; Lithospermeae; Toxicity; Pyrrolizidine alkaloids; Pan-Himalaya; HPLC