Phytopharmacognostic Evaluation of the Leaves OF Gnetum africanum Welw (Gnetaceae)

Background: Gnetum africanum Welw (Gnetaceae) also called African salad and Afang in Ibibio language is an evergreen, perennial, shade-tolerant vine with woody stems which can climb up to 12m or more from a tuberous root-stock. It has culinary and medicinal importance.

Objective: The aim of this study was to evaluate pharmacognostic parameters of Gnetum africanum.

Methods: The leaves were identified, collected, air-dried, pulverized, weighed and subjected to the evaluation of its microscopy, micromeritics, chemomicroscopy, fluorescence, soluble extractive values, moisture content and ash values using standard procedures.

Results: The results obtained from microscopy revealed that the leaf has brachyparacytic, stomata, 3-5 armed and stellate trichromes on the abaxial surface. The epidermal cell wall pattern was undulate on the abaxial surface and sinuous on the adaxial surface. Stomatal number was found to be 3.1 ± 0.25 on the abaxial surface and Stomatal index was found to be 16.8% on the abaxial surface. The micromeritics analysis of the leaf powder revealed passable flow with the angle of repose of 420. The result of chemomicroscopy of the leaf revealed the presence of mucilage, lignin, calcium oxalate crystals, starch and oil. For water-soluble extractive value, the result was 13.25%w/w, methanol-soluble extractive value 4.25%w/w, ethanol-soluble extractive value 4%w/w, moisture content 10.5%w/w, total ash value was 5%w/w, acid-insoluble ash value 1%w/w, water-soluble ash value 2%w/w and sulfated- ash value 6% w/w.

Conclusion: The results obtained from the pharmacognostic study provides information for the identity, quality and purity of Gnetum africanum.