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Aqueous and ethanolic leaf and stem extracts of Gnetum africanum were investigated for the presence and composition of these phytochemicals (alkaloid, flavonoid, tannin, phenol, saponin, sterol, terpenoid and cyanogenic glycoside) and their antifungal and antibacterial activities at various concentrations against some selected clinical microbes (fungal strains: Candida albicans and Aspergillus niger and bacterial strains: Staphylococcus aureus, Escherichia coli and Salmonella typhi) using standard methods. Analysis of variance (ANOVA) was employed in data analysis. Qualitative and percent quantitative phytochemical results showed that both the aqueous and ethanolic leaf and stem extracts contained these phytochemicals assayed but at varied quantities except cyanogenic glycoside. Antifungal and antibacterial studies indicated that both the aqueous and ethanolic leaf and stem extracts of Gnetum africanum inhibited the growth of the microbes but at varied levels and the inhibition was extracts concentration dependent. However, both the aqueous and ethanolic leaf and stem extracts showed no inhibition against the bacterial strains at 50 mg mLG 1 of the extracts. The extracts showed higher inhibition against the fungal strains than the bacterial strains. Inhibitory effect of the leaf extract was significantly higher than those of the stem extract. The ethanol extract showed significantly higher inhibition than the aqueous extract. Antibiotics had a better activity when compared to the extracts at the same concentration. Gnetum africanum extracts were biostatic in their action, when purified will give a product with higher activity. The data obtained from the study indicated that the plant possessed antifungal and antibacterial potentials especially antifungal and could be used as natural fungicides.

Anatomical studies of transverse, tangential and radial longitudinal sections of roots, stems and leaves of two species of Dracaena present in southeastern Nigeria were investigated, to determine their anatomical features with regards to arrangement of vascular bundles in their roots, stems and leaves and type of secondary growth occurring in them using standard method. T-test was used for the analyses. Result showed that the number of vascular bundles in the leaves and roots of D. arborea are more in number than those of D. mannii but the reverse is the case in the stem. Secondary growth occurs in both D. mannii and D. arborea. The overall analyses showed no significant statistical difference in the anatomy of the two Dracaena species. The implication is that the two species are closely related and this justified their placement under the same genus Dracaena while the slight differences between them suggest the reason for their separation into different species.

Phytochemical evaluation of leaves, stems and roots of Dracaena arborea (Link) and Dracaena mannii (Bak) present in southeastern Nigeria was carried out, to determine their taxonomical data with regards to their phytochemicals contents (flavonoid, saponin, tannin, cyanide, lectin, phytate and calcium oxalate) using standard methods. The results show varying quantities of the phytochemicals in the leaves, stems and roots of the two Dracaena species with some parts lacking some of the phytochemicals. The highest quantity of the phytochemicals was contained in the leaves of both species when compared to other parts respectively. The result also revealed no significant statistical difference in the phytochemistry of the two Dracaena species. The implication is that the two species are closely related and this justified their placement in the same genus Dracaena while the slight differences between them support their separation into different species. The result also indicated that the two species could be used in ethnomedicine for the treatment of diseases. In addition, these parts could be the possible sources of these phytochemicals.