Anatomical Characterization of Stems of Some Medicinal Plants of the Family Euphorbiaceae in Nigeria

Background and Objective: Detailed knowledge of plant anatomical characters and their variation among closely related species is paramount to understanding their evolution and function. Plants belonging to the Euphorbiaceae family are widely used in Nigeria since it has important secondary metabolites like tannins, alkaloids, flavonoids, phenols, triterpenes, polysterols, etc. Euphorbiaceae is an important family which contains numerous medicinal plants. Based on their medicinal importance, seven species were selected for study from four genera which include: Genus Acalypha-A. hispida and A. wilkesiana, genus Euphorbia-E. heterophylla and E. hirta, genus Jatropha-J. curcas and J. gossypifolia and the genus Manihot-M. esculenta. Materials and Methods: This study characterizes and compares the anatomical characteristics of the stem of these seven species of Euphorbiaceae occurring in some parts of the Niger Delta Region of Nigeria, as a means of providing information for quality assessment of the herbal industry. Three individuals of each species were collected, fixed, stored and prepared following usual anatomy techniques, for subsequent observation using light microscopy techniques. Results: The observations made of the transverse sections of the stem revealed structural arrangements and variations of the epidermis, hypodermis, cortex, vascular tissues and pith. The cell wall contours have been described in detail. The occurrence of cell inclusions was also noted in different tissues of the stem-axes. Conclusion: The observable characters in the seven species studied are diagnostic and taxonomically significant enough to separate and distinguish them. These features are helpful when conducting a quality control process.