The phytochemical constituents and the antimicrobial activity of the methanolic and acetone extracts of Vitex doniana (Sweet) fruit were investigated to ascertain its biological potentials. The study revealed that the fruit contained alkaloids, flavonoids, saponins, phenols, tannins, steroids and cardiac glycoside. The percentage proximate composition of the fruit of the plant were as follows: moisture 10.00%, ash 18.00%, crude fibre 4.50%, crude protein 0.60%, carbohydrate 43.20% and crude lipids 23.70%. The elemental analysis confirmed the presence of calcium, magnesium, potassium and sodium. The methanolic and acetone extracts of the fruit of the plant were tested against Escherichia coli, Staphylococcus aureues, Pseudomonas areuginosa and Klebsiella pnuemoniae by the agar (Mullen-Hinton) diffusion method. The zone of inhibition for the methanol extract ranged between 10.50 to 21.00 (mm) for all concentrations (1000, 500 and 250 mg/ml). While the acetone extract only inhibited the growth of Escherichia coli to 7.50mm at a concentration of 1000mg/ml. The results obtained indicate that the fruit extracts have antimicrobial importance and can be utilized in the treatment of some ailments and malnutrition.

Chalcones were synthesized via Claisen-Schmidt condensation between various substituted acetophenone and benzaldehyde using 20% cold alcoholic KOH as catalyst. Two Schiff bases were synthesized through the condensation reaction of the synthesized chalcones with 2,4-dinitrophenylhydrazine using concentrated H2SO4 as catalyst. The antimicrobial properties of the Schiff bases were determined using the standard disc diffusion method of anti-microbial sensitivity according to CLSI. The results of anti-microbial analysis were compared to ciprofloxacin and ampicillin as reference standards. The first Schiff base was N-(2,4-Dinitro-phenyl)-N'-(1,3-diphenyl-allylidene)-hydrazine (SB1), a hydrazone of 1,3-diphenylprop-2-en-1-one and the second was N-[3-(4-chloro-phenyl)-1-phenyl-allylidene]-N'-(2,4-dinitro-phenyl)-hydrazine (SB2), a hydrazone of 1-phenyl-3-(4-chlorophenyl)-prop-2-en-1-one. SB1 had a percentage yield of 97.57% and a decomposition temperature of 231-2340C while SB2 gave 98.74% as percentage yield and a melting point of 216-2180C. SB1 showed anti-microbial properties while SB2 showed no anti-microbial properties when both were tested against Staphylococcus aureus and Pseudomonas aeruginosa at a concentration of 10 mg/mL. SB1 had a diameter zone of inhibition of 4-6 mm for P. aeruginosa and 7-9 mm for S. aureus. SB1 was more effective against g positive than g negative bacteria at a concentration of 10 mg/L. The presence of the major absorption band in the range of 350-375 nm, attributable to the n-π* transition of aromatic ketones in the UV spectra of the synthesized chalcones gave credence to their proposed aromatic structure. The presence of strong bands at 1604 cm-1 for SB1 and 1601cm-1 for SB2 and the absence of carbonyl oxygen absorption band in their IR spectra gave credence to the formation of Schiff bases.

The phytochemical constituents and the antiulcerogenic activity of methanolic extract from Ipomoea asarifolia leaf were investigated to ascertain its medicinal potentials. The study revealed that the leaf contained saponins, tannins, alkaloids, terpenoids and eugenols. The methanolic extract was used as a protective agent against gastric ulcer in Wistar rats, using the experimental model of gastric ulcer (lesion) induced by ethanol. The ulcer count for the methanol extract ranged from 0.00 to 2.00, while the ulcer index ranged between 0.33 to 2.00 for all concentrations (100, 200 and 400mg/kg). Percentage inhibition at 100, 200 and 400mg/kg were respectively 25.09%, 12.73% and 87.64%. The extract prevented acute gastric mucosal injury induced by absolute ethanol in a non dose-dependent manner. This is because the protective action was observed at the lowest and highest doses, but not an intermediate dose of the extract. The results obtained indicate that the leaf extract has antiulcerogenic importance and may be utilized for the treatment of gastric ulcers.

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