Anatomical studies and nutritional analysis of the leaf extract of Plukenetia conophora

Abstract

Background and aim: Plukenetia conophora Mull. Arg. (African walnut) belongs to the Euphorbiaceae family. The
significance of wood anatomy in relation to taxonomy is by no means new or recent. Aim: The work evaluates the
anatomy of the leaf, stem, root and the nutritional values of the leaves of Plukenetia conophora. Methodology: Leaf
epidermal strips were made by Impression technique and all sectionings (TS, TLS and RLS) were made with Reichert
sliding microtome. Standard stains were used to differentiate the tissues. The proximate and mineral analyses were
carried out using standard methods. Results: Anatomical studies showed hypostomatic leaves with anomocytic
stomata and no trichomes. Concentric vascular bundles were observed in the transverse sections of the leaf and
petiole. The various sections of the stem anatomy revealed diffuse-in-aggregate vessels with scanty axial parenchyma
in the transverse section, both uniseriate and biseriate rays in the transverse longitudinal section, and procumbent rays
in the radial longitudinal section. Nutritional analysis showed presence of all the tested proximate and minerals. The
leaves contained proximate: carbohydrates (25.57 ± 0.05), protein (18.02 ± 0.02), ash (29.36 ± 0.33), moisture (18.06
± 0.03), crude fibre (9.83 ± 0.17) and fat (7.41 ± 0.11) and minerals: calcium (19.18 ± 0.00), potassium (14.01 ± 0.00)
and sodium (7.97 ± 0.03), Zinc (0.70 ± 0.01), magnesium (1.91 ± 0.01), iron (4.93 ± 0.04) and manganese (0.91 ±
0.00). Conclusion: The anatomical results are quite useful in the delimitation of this species and nutritional results
suggest the use of the leaves as a healthy food.