Pharmacognostic Characteristics and Mutagenic Studies of Alstonia boonei De Wild

The bark of Alstonia boonei, known as stool wood, is sold in large quantities on the Ghanaian market. It is used for the treatment of numerous ailments including snake bites, worm infestation, malaria and rheumatic pains. For safety reasons, it is necessary to control the raw materials by setting simple but relevant parameters to ensure identity, purity and quality which have been the aim of the present study to authenticate the plant materials.

The macroscopic, microscopic, physico-chemical, phytochemical, UV-visible, fluorescence, HPLC and elemental characteristics were evaluated. Mutagenicity was also investigated with the Ames test.

The leaf characteristics can be employed to preliminary confirm the identity of the plant.The greyish-green outer bark and inner cream bark is rough, short and splintery with a bitter taste.The powdered stem bark showed microscopic prismatic calcium oxalate crystals, scalariform xylem vessels and lignified brachysclereids. Phytochemicals present were alkaloids, saponins, tannins, flavonoids, glycosides and terpenes. The bark fluoresced reddish-brown in 50 %v/v H2SO4 under UV light of λ 254 nm and contained traces of Cd, Fe, Zn and As, which were within recommended limits. HPLC fingerprint showed peaks at 254 nm, and UV analysis in various solvents showed spectral shifts on ionization. A. boonei demonstrated mutagenicity in Ames test.

The characteristic macroscopic, microscopic, physico-chemical and chemical parameters evaluated for the plant sample can be used in rapid identification, authentication and establishment of the quality of raw materials. This will improve the quality and hence efficacy. The mutagenicity suggests the need for further safety evaluation.