Shi C.,University of Minnesota |
Geders T.W.,University of Minnesota |
Park S.W.,New York Medical College |
Wilson D.J.,University of Minnesota |
And 7 more authors.
Journal of the American Chemical Society | Year: 2011
BioA catalyzes the second step of biotin biosynthesis, and this enzyme represents a potential target to develop new antitubercular agents. Herein we report the design, synthesis, and biochemical characterization of a mechanism-based inhibitor (1) featuring a 3,6-dihydropyrid-2-one heterocycle that covalently modifies the pyridoxal 5′-phosphate (PLP) cofactor of BioA through aromatization. The structure of the PLP adduct was confirmed by MS/MS and X-ray crystallography at 1.94 Å resolution. Inactivation of BioA by 1 was time- and concentration-dependent and protected by substrate. We used a conditional knock-down mutant of M. tuberculosis to demonstrate the antitubercular activity of 1 correlated with BioA expression, and these results provide support for the designed mechanism of action. © 2011 American Chemical Society.
Anjorin T.S.,University Of Abuja |
Ikokoh P.,Chemistry Advanced Laboratory |
Okolo S.,Chemistry Advanced Laboratory
International Journal of Agriculture and Biology | Year: 2010
The mineral composition of the lamina, petiole, seed pod, seed shell, seed kernel powder and seed kernel oil of Moringa oleifera L. from two regions, Sheda and Kuje, Abuja, Nigeria were investigated. The results indicated that Ca, Mg, Fe and Cu in M. oleifera leaves, pods and seeds from Sheda were relatively higher than that from Kuje. Relatively high contents of Ca and Fe were found in the lamina and seed shell of the plant respectively from both regions. The Mg content (0.185 mg mL-1) in the seed kernel oil of moringa from Sheda was significantly lower (P ≤ 0.05) than that in the other parts of leaf and seed. The Fe content in the seed shell from Sheda was 0.2436 mg g-1 more than those from Kuje. Toxic element such as Pb was absent in the leaves, pods and seeds of moringa from both locations. This study confirmed that there are variations in macro and trace minerals in moringa leaves, pods and seeds from different locations. This finding might be a reference point in the selection and formulation of plant-based mineral supplement in animal and human nutrition. © 2010 Friends Science Publishers.
Okwute Simon K.,University Of Abuja |
Okolo Simon C.,Chemistry Advanced Laboratory |
Okoh-Esene R.,Chemistry Advanced Laboratory |
Olajide Olutayo O.,Chemistry Advanced Laboratory
International Journal of ChemTech Research | Year: 2014
The leaf of Phyllanthus amarus was investigated for its chemical and biological properties. The powdered leaf was extracted with 95% ethanol and the crude extract was partitioned successively with hexane, dichloromethane, ethyl acetate and 70% aqueous methanol. Phytochemical analysis of the crude extract showed that it contained alkaloids, balsams, flavonoids, saponins, steroids, tannins, terpenoids, and anthraquinones. The proximate analysis revealed that Phyllanthus amarus leaf is a good source of carbohydrates, proteins and fibre. The crude extract and fractions were tested against Pseudomonas aeruginosa,Escherichia coli, Staphylococcous aureus, and Candida albicans for their antimicrobial and antifungal activities. Flash column chromatographic separation of the antimicrobial dichloromethane fraction gave a partially pure isolate which on GC-MS analysis revealed the presence of 2- naphthyl-α- D-galactopyranoside and 9-octadecenoic acid in the leaf extract. © 2014-2015, Sphinx Knowledge House. All rights reserved.
Danlami U.,Chemistry Advanced Laboratory |
Rebecca A.,Chemistry Advanced Laboratory |
Machan D.B.,Chemistry Advanced Laboratory |
Asuquo T.S.,Chemistry Advanced Laboratory
Journal of Applied Pharmaceutical Science | Year: 2011
The ethanolic extracts of the leaves of Lemon grass and Polyalthia Longifolia were subjected to antibacterial activity study. The study indicated that the extract of the leaves of Lemon grass was very active against Klebsiella pneumonia and Staphylococcus aureus at 25mg/ml buthas no activity with Bacillus subtilis and Escherichia coli at the same concentration. The extract of Polyalthia Longifolia leaves was very active against Bacillus subtilis and Staphylococcus aureus at 25mg/ml but has no activity with Klebsiella pneumonia and Escherichia coli at the same concentration. The extracts when combined together can act synergistically with one another against Staphylococcus aureus, where one extract can potentiate the activity of another extract against Staphylococcus aureus.The minimum inhibitory concentration (MIC) of the crude extracts were determined for the various organisms which ranged between 0.01 and 2.5mg/ml,whil the minimum bactericidal concentration (MBC) ranged between 0.02 and 2.5mg/ml.