Pharmacognostic and proximate evaluations of the leaves, stem bark and roots of Boswellia dalzielii Hutch (Burseraceae)
Pharmacognostic studies helps in the quality control of plant materials through proper identification, authentication and standardization. The aim of this study was to establish the pharmacognostic characters of the leaf, stem bark and root of Boswellia dalzielii towards monograph development. Pharmacognostic studies; organoleptic, microscopic, macroscopic, physicochemical, phytochemical and proximate analysis were conducted using standard procedure. Macroscopic study indicated that the leaf is lanceolate in shape. The apex is acute, and the margin is serrate with parallel venation. The upper surface is green with smooth midrib, while the lower surface is pale green with non-prominent midrib. The stem bark is 1.2 cm (12 mm) thick, the external surface is rough and thin while the internal surface is fibrous and rough. The root is of cylindrical type. The microscopic diagnostic characters of the leaf includes anomocytic stomata, unicelluler non-glandular trichomes and calcium oxalate prism. The distinguishing characters of the stem bark were parenchyma, cork cells, calcium oxalate prism, numerous pitted vessels, medullary rays and sclereids. The microscopical result of the root revealed the following diagnostic characters; cork cells, pitted vessels, fibre, calcium oxalate prism, starch grains and multicellular multiseriate medullary ray. The chemomicroscopic examination of the leaf revealed the presence of lignin, suberin, starch, tannin, mucilage and calcium oxalate prism. Both the stem bark and the root revealed the presence of lignin, oil globule, starch, tannin, protein and calcium oxalate prism. The phytochemical screening of the leaf, stem bark and roots revealed the presence of saponins, tannins, flavonoids, cardiac glycosides and terpenes. The physicochemical analysis resulted in parameters that can be useful in ascertaining the quality and purity of the plant. The proximate analysis revealed proportions of nutrients and their contents present in the plant. This study provides the scientific data for the proper identification and establishment of standards for the use of Boswellia dalzielii.
Keywords: Pharmacognostic, Proximate analysis, Boswellia dalzielii