Anthelmintic activity-guided fractionation and GC-MS analysis of extracts from Embelia schimperi fruits

摘要

Summary. Embelia schimperi Vatke (Myrsinaceae) is one of the common Ethiopian medicinal plants that has been traditionally used as anthelmintic remedy. Locally the plant is known as Enkoko. So far the activity was attributed to embelin (1). However, evidences suggesting the potential anthelmintic activity of other constituents of E. schimperi have not been provided yet. This study, therefore, aimed at the in vitro anthelmintic activity-guided isolation and determination of further bioactive metabolites from E. schimperi. Fruits of E. schimperi were extracted with 80% aqueous MeOH and the aqueous residue was successively partitioned with n-hexane and ethyl acetate. The n-hexane extract was purified with sephadex LH-20 column chromatography followed by silica gel column chromatography. The anthelmintic activity of extracts and fractions against Caenorhabditis elegans was determined by microscopic enumeration of living and dead worms. The fractions with high anthelmintic activity were analyzed by GC-MS. The n-hexane extract exhibited significant anthelmintic activity against the model organism C. elegans. The subsequent fractionation procedure resulted in two active fractions. The GC-MS structural characterization of these nonpolar active fractions revealed the presence of fatty acids 2-10 (do-, tri-, tetra-, hexadecanoic acid, palmitoleic, oleic, linoleic, linolenic acid) and 5-alkyl substituted resorcinol derivatives with C9 to C13 side chains (11-14). In addition to embelin (1), the identified nonpolar constituents of E. schimperi might contribute to the anthelmintic activity of this plant species.Industrial relevance. Helminthic diseases constitute a worldwide threat and most of the developing nations that are affected by helminth infections rely on anthelmintic medicinal plants including E. schimperi. This study reports the anthelmintic properties and chemical constituents of the n-hexane extract of E. schimperi and the fractions obtained therefrom, which might be used as phytodrugs after further studies.