Unveiling the secrets of forgotten plants: Molecular networking-based phytochemical study of Geissospermum laeve (Vell.) Miers

The approaches for the detection of natural products have evolved into more sophisticated ones thanks to the benefits of the big data era. In that context, a dereplication technique, called molecular networking, has been exploited by our team to undertake the phytochemical study of Geissospermum laeve (Vell.) Miers, a South American plant belonging to the Apocynceae family [1]. Applying this approach we sought the identification and isolation of minor compounds presenting original chemical structures. The molecular networking is based on the acquisition of chromatographic and spectral data by HPLC-ESI-Q/TOF, which then is displayed in the form of molecular networks of MS/MS fragmentation [2]. The application to the ethanolic extract from the stems of the plant allowed the identification and subsequent isolation of three new molecules, with a particularly original novel skeleton within the broad class of monoterpenoid indole alkaloids. Their isolation, structural elucidation, cytotoxicity and antiplasmodial activities are presented in this communication.

Acknowledgements: CONCYTEC is acknowledged for financing Alexander Fox's grant.

Keywords: HPLC-ESI-Q/TOF, molecular networking, monoterpenoid indole alkaloid, Geissospermum laeve.

References:

[1] Mbeunkui F, Grace MH, Lategan C, Smith PJ, Raskin I, Lila MA. In vitro antiplasmodial activity of indole alkaloids from the stem bark of Geissospermum vellosii. J Ethnopharmacol 2012; 139: 471 – 477

[2] Yang JY, Sanchez LM, Rath CM, Liu X, Boudreau PD, Bruns N, Glukhov E, Wodtke A, de Felicio R, Fenner A, Wong WR, Linington RG, Zhang L, Debonsi HM, Gerwick WH, Dorrestein PC. Molecular networking as a dereplication strategy. J Nat Prod 2013; 76: 1686 – 1699