Triterpenoid saponins from the cytotoxic root extract of Sideroxylon foetidissimum, an endemic Yucatecan medicinal plant

A. Sánchez-Medina; P. C. Stevenson; S. Habtemariam; L. M. Peña-Rodríguez; O. Corcoran; T. A. Mallet; N. C. Veitch

doi:10.1055/s-0028-1083893

Planta Medica, Table of Contents

Triterpenoid saponins from the cytotoxic root extract of Sideroxylon foetidissimum, an endemic Yucatecan medicinal plant

A Sánchez-Medina ¹^,³, PC Stevenson ², S Habtemariam ³, LM Peña-Rodríguez ⁴, O Corcoran ¹, TA Mallet ³, NC Veitch ²

¹Medicines Research Group, School of Health and Bioscience, University of East London, University House, Romford Road, London, UK, E15 4LZ
²Jodrell Laboratory, Royal Botanic Gardens, Kew, Surrey, UK, TW9 3DS
³Medway School of Science, the University of Greenwich, Central Avenue, Chatham Maritime, Kent, UK ME4 4TB
⁴Grupo de Química Orgánica, Unidad de Biotecnología, Centro de Investigación Científica de Yucatán, A.C., Calle 43 No. 130 Col. Chuburná de Hidalgo. CP 97200, Mérida, Yucatán, México

Abstract

The flora of the Yucatan peninsula (Mexico) includes approximately 3000 plant species. Sideroxylon foetidissimum Jacq. subsp. gaumeri (Sapotaceae) is an endemic plant to the Yucatan peninsula; its fruit is edible and local people use the plant for medicinal purposes, although no details on its preparation or application are available [1,2]. A preliminary cytotoxic evaluation of the ethanolic root extract of S. foetidissimum revealed a potent activity against murine macrophage like cell line RAW 264.7 (IC₅₀=39.54±4.11µg/mL). The systematic bioassay-guided fractionation of the extract resulted in the identification of the active saponin-containing fraction (IC₅₀=33.69±6.19µg/mL). Four new triterpenoid saponins and a 1:1 mixture of two saponins were isolated from the active saponin- containing fraction. The evaluation of their cytotoxic activity revealed no activity for the tested pure saponins; however, the 1:1 mixture of saponins showed a potent activity (IC₅₀=11.91±1.49µg/mL). The isolation of the saponins was carried out using semi-preparative HPLC. The structural assignments of the pure saponins were based on 1D (¹H and ¹³C and DEPT-135) and 2D (COSY, HMBC, HSQC and TOCSY) NMR and mass spectrometry analyses. In this presentation, the isolation, identification and cytotoxic activity of the isolated compounds is discussed in more detail.

Acknowledgements: Centro de Investigacion Cientifica de Yucatan, Mr. Filogonio May Pat for his assistance in the collection, identification and preparation of the voucher specimens of the collected plant species.

References: 1. Espadas-Manrique, C. et al. (2003) Diversity and Distributions 9:313–330. 2. Durán, H. et al. (2000). Harvard Papers in Botany 3:263–314.