ir.bowen.edu.ng:8181/jspui/handle/123456789/343 These are articles published in journals by academics staff Fri, 03 Apr 2026 00:03:14 GMT 2026-04-03T00:03:14Z ir.bowen.edu.ng:8181/jspui/handle/123456789/2848 Title: Adsorption kinetics of cadmium and lead by chitosan Authors: Bamgbose, J. T.; Adewuyi, S.; Bamgbose, O.; Adetoye, A. A. Abstract: An evaluation of the kinetics and capacity of chitosan to trap lead and cadmium ions in aqueous solution was carried out at 25°C using concentration and contact time as parameters. The experiments were done as batch process. Our results show that the adsorption process is concentration-driven with high capacity of chitosan for the adsorption of these metal ions. The infrared spectroscopic study on the chitosan and the metal-chitosan complexes reveals a metal coordination based on the observed characteristic band changes. At initial lead concentrations of 1000, 500, 400, 250 and 100 mg/L, the adsorbed lead ion concentrations are 557, 265, 218, 132 and 65 mg/L, respectively. However, for the cadmium, the adsorbed concentrations are 263, 165, 152, 78 and 45 mg/L, respectively at the same initial concentrations. The lead and cadmium adsorption kinetic behavior could not be described using the Langmuir isotherm over the whole concentration range but Freundlich isotherm conforms to the experimental data. Fri, 01 Jan 2010 00:00:00 GMT ir.bowen.edu.ng:8181/jspui/handle/123456789/2848 2010-01-01T00:00:00Z ir.bowen.edu.ng:8181/jspui/handle/123456789/2845 Title: Studies on enhanced African black soap from Theobroma cacao (cocoa) and Elaeis guineensis (palm kernel oil) Authors: Ikotun, A. A.; Faboro, E. O.; Kolade, A. S.; Owoseni, A. A. Abstract: The indigenous African organic soap is formed by saponification. Using the local and ancient method, with slight modifications, palm kernel oil (Elaeis guineensis) and the filtrate of burnt cocoa pod ash (Theobroma cacao) were used to prepare African black soap (C11H23COO-K+). The prepared black soap was thereafter divided into five parts. Part A was the control without additives, while parts B, C and D were enhanced with aloe vera, camwood and lime respectively. Part E was enhanced with both shea butter and camwood. These samples were analyzed chemically by pH determinations, infrared spectroscopic analyses and phytochemical screenings. They were also screened for in-vitro antibacterial activities against two Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis) and two Gram-negative bacteria (Pseudomonas aeruginosa and Escherichia coli). The pH determinations showed that all the samples were alkaline in nature with values between 8.7 and 9.1. Infrared spectra analyses of the unenhanced black soap revealed a medium and a strong band due to υ (C=O) frequency of the keto group at 1740 and 1562 cm-1 respectively and a medium band at 1119 cm-1 due to υ (C-O) frequency of the ester oxygen. These bands appeared almost unchanged in the Infrared spectra of the enhanced samples, signifying no complexation through the oxygen donor atoms. Thus, the structure of the black soap (A) was intact and it was not denatured by the various additives. Phytochemical screenings revealed that A and D contained saponins, flavonoids and terpenoids; C contained both flavonoids and terpenoids; B and E contained only terpenoids; while tannins and steroids were absent in all the samples. Antimicrobial studies showed that the enhanced black soap were either active against one or both gram-negative bacteria. In addition B, C and D were also active against either one or both gram-positive bacteria. E was inactive against the gram-positive bacteria, while the unenhanced black soap remained inactive against all tested organisms. Mon, 01 Jan 2018 00:00:00 GMT ir.bowen.edu.ng:8181/jspui/handle/123456789/2845 2018-01-01T00:00:00Z ir.bowen.edu.ng:8181/jspui/handle/123456789/2844 Title: Synthesis, physicochemical and antimicrobial properties of rhenium (I) tricarbonyl complexes of isatin Schiff bases Authors: Ikotun, A. A.; Owoseni, A. A.; Egharevba, G. O. Abstract: The Schiff base of isatin and sulphanilamide (L1; C14H11N3O3S) was prepared and reacted with Re(CO)5X (X = Cl and Br) in toluene to give [Re(C14H10N2O)(CO)3X] (X = Cl, 1 and X = Br, 2). The prepared Schiff base of isatin and 4-methoxyaniline (L2; C15H12N2O2) was reacted with Re(CO)5X in toluene to give [Re(C14H10N2O)(CO)3X], where X = Cl, 3 and X = Br, 4. L2 and Re(CO)5Br were refluxed in dry toluene under nitrogen and recrystallized to give [Re(C15H12N2O2)(CO)3Br].½C2H5OH (5). Spectroscopic characterization of compounds was done using FTIR, UV-Visible, NMR and Mass spectra analyses. Magnetic susceptibility measurements and melting points were also determined. Elemental analysis of 5 revealed it was a solvate molecule of 4. The in-vitro antimicrobial activities of compounds were evaluated against Staphylococcus aureus, Bacillus subtilis, Haemolytic Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Klebsiella sp., Aspergillus niger, Trichoderma viride and Penicillium citrinum. Spectroscopic analyses revealed new terminal carbonyl bands formed between 1900 and 2030 cm-1, as L1 and L2 coordinated through their azomethine nitrogen and keto oxygen donor atoms towards Re(I). Results of the antimicrobial studies revealed immerse improved activities upon coordination against tested microorganisms especially gram-negative bacteria, therefore, they are recommended for further studies in cell imaging. Fri, 01 Jan 2021 00:00:00 GMT ir.bowen.edu.ng:8181/jspui/handle/123456789/2844 2021-01-01T00:00:00Z ir.bowen.edu.ng:8181/jspui/handle/123456789/2841 Title: Synthesis and antibacterial activity of metal complexes of barbituric acid Authors: Ikotun, A. A.; Ojo, Y.; Obafemi, C. A.; Egharevba, G. O. Abstract: Cobalt (II), copper (II), iron (III), manganese (II) and nickel (II) complexes of barbituric acid were synthesized and characterized by infrared and ultraviolet spectroscopy. The ligand and the complexes have been screened for in vitro antibacterial activity against a range of Gram-positive and Gram-negative bacteria (Bacillus authracis, Bacillus cereus, Bacillus stearothermophilus, Bacillus subtilis, Escherichia coli, Klebsiella pneumonia, Pseudomonas aeruginosa, Pseudomonas fluorescens, Staphylococcus aureus, Streptococcus faecalis). Cobalt (II) complex displayed a better antibacterial activity than the ligand, showing a broad-spectrum activity against all six Gram-positive and four Gram-negative bacterial strains, while the other complexes showed only selective activity against the organisms in a manner similar to the starting ligand. Sat, 01 Jan 2011 00:00:00 GMT ir.bowen.edu.ng:8181/jspui/handle/123456789/2841 2011-01-01T00:00:00Z