CYTOTOXIC ACTIVITY OF THE CONSTITUENTS OF ANTHOCLEISTA DJALONENSIS AND THEIR DERIVATIVES

Abstract

Crude methanol extracts obtained from the stem, roots and leaves of Anthocleista djalonensis and three natural plant constituents (djalonenol 1, sweroside 3 and djalonensone 9 respectively) isolated from these extracts were evaluated invitro against ST-57 brain tumor transformed fibroblasts. In addition, six semisynthetic derivatives (djalonenol diacetate 2, sweroside tetraacetate 4, dihydrosweroside 5, dihydrosweroside tetraacetate 6, 1-methoxy sweroside 7 and hydrolytic dimmer of sweroside 8 respectively) were also evaluated to assess the effect of derivitization on cytotoxicity of natural plant constituents. The primary culture of fibroblasts was prepared by the method of explantate culture. Comparatively, the three crude extracts as well as compounds 1, 3 and 7 exhibited low cytotoxicity (ED₅₀ 40-70μg ml^-1). Derivitization of the plant constituents only enhanced the cytotoxicity of compound 8 (ED₅₀ 4μg ml^-1). Compounds 2, 4, 5, 6 and 9 were not significantly cytotoxic against the brain tumor transformed fibroblasts. However the extracts and compounds exhibited concentration and time dependent activities. This is consistent with the observed toxic effect of the use in large doses of A. djalonensis in traditional medicine.


Key Words: Anthocleista djalonensis; Loganiaceae; Cytotoxicity; fibroblasts; djalonenol; djalonensone and Sweroside.


Nigerian Journal of Natural Products and Medicine Vol.7 2003: 58-60