A phytochemical study of selected medicinal herbs

Abstract

Medicinal plants have played an important part in the establishment of human culture. They have played a crucial role in the development of some drugs currently in the market. This study illustrates the significance of traditional medicines in treating and managing human diseases such as malaria. Nine medicinal plants, Lavandula x intermedia, Artemisia afra, Rosmarinus officinalis, Cymbopogan citratus, Verbascum thapsus, Pelargonium graveolens, Foeniculum vulgare, Lippia citriodora, Catharathus roseus were studied and their petroleum ether, chloroform, ethyl acetate, ethanol and acetone extracts were used for the phytochemical screening to investigate the phytoconstituents in the medicinal herbs. The results disclosed the occupancy of secondary metabolites mostly flavonoids, sterols and saponins. This was coupled with antimalarial tests to evaluate the therapeutic potential of the extracts of the nine selected plant species as potential antimalarial agents. The dichloromethane, ethanol and acetone extracts of the nine species were screened in vitro for antimalarial activity using NFss sensitive strain using pLDH method. From the screening results Artemisia afra and Cymbopogan citratus warrantied further investigation and their IC5o values were 0.71 and 4.59 respectively. Based on the availability, Artemisia afra was investigated further resulting in the isolation of taurin ( 4.24) and marimatin ( 4.25). These two pure compounds were investigated for their antimalarial activity.