Microscopic characterization of medicinal plants commonly used in Ethiopia

In Ethiopia the traditional use of medicinal plants has a long history. Numerous ethnopharmaceutical publications document widely used plants in this country. These reports were developed by questioning of community members, healers, traders and collectors. Based on these publications we focus on commonly used medical plants. In pharmacognosy, the exact taxonomic classification should be combined with a microscopic monograph for an unambiguous identification. Here we present the microscopic characterization of five plants collected in different regions of Ethiopia.

Dodonaea viscosa ssp. angustifolia (leaf and fruit, Sapindaceae): The leaves have a bifacial structure. Glandular trichomes are visible on both epidermis sides. The fruits show an epidermis like exocarp with glandular trichomes, a netlike sclerified mesocarp and a sclereid layer as an endocarp. Syzygium guineense (bark, Myrtaceae): The bark shows stone cells and fiber bundles. Young twigs are characterized by oil cavities typical for a Myrtaceae. Ruta chalepensis (leaf, Rutaceae): The leaves are bifacial with a bilayer palisade parenchyma. Anomocytic countersunken stomata are countable in the lower epidermis only. Rutaceae-typical oil cavities are located in the mesophyll. Solanum incanum (root and fruit, Solanaceae): The roots contain the Solanaceae-typical idioblasts with calcium oxalate sand. Embelia schimperi (fruit, Primulaceae): The pericarp shows an epidermis like exocarp. The mesocarp contains sclereids and oil cavities. The endocarp is a bilayer of highly packed stone cells. In the case of Embelia schimperi the microscopic features of fresh plant material were compared to dried material from a traditional marketplace.

Acknowledgement: This presentation on microscopic characterisation of Ethiopian medicinal used plants is part of the project “Welcome to Africa” which is supported by the DAAD.