A pharmacobotanical study of two medicinal species of Fabaceae

To carry out a pharmacobotanical study of Lonchocarpus cyanescens (Schum & Thonn) Benth (L. cyanescens) and Leptoderris micrantha Dunn (L. micrantha) which are two key medicinal plants from the family Fabaceae.

The epidermal peel was obtained by soaking the leaf in concentrated nitric acid (HNO3) in a petri dish. Both surfaces were carefully mounted on clean glass slides and dehydrated by ethyl alcohol, and stained with safaranin O for 2 min. Transverse sections of plant leaf were obtained by free hand sectioning. Phytochemical screening for various constituents was carried out on the powdered leaves. Other parameters such as, moisture content, ash value, acid insoluble ash, water-soluble ash, water and alcohol extractive values were obtained by standard techniques.

THE DISTINCTIVE FEATURES OF THE SPECIES INCLUDE: the presence of stomata on both surfaces of L. cyanescens and the absence in L. micrantha. Presence of larger epidermal cells in both upper and lower surfaces of L. cyanescens [(35.25±1.64)×(31.25±2.36), (43.0±2.63)×(39.5±5.11)] respectively compared to L. micrantha. Glandular multicellular trichomes are present in L. micrantha but absent in L. cyanescens. Numerous trichomes surround the transverse section of the leaf of L. micrantha but absent in L. cyanescens. Preliminary phytochemical screening showed that both species contain secondary metabolites such as alkaloids, anthraquinones, cardiac glycosides, tannins, saponins, steroids and flavonoids.

The microscopic and phytochemical data provided in this study are useful for the standardization of the medicinal plants.