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Aliyu B.,Modibbo Adama University of Technology, Yola | Agnew B.,Northumbria University | Douglas S.,University of Nairobi
Biomass and Bioenergy | Year: 2010

This work provides details of an activity undertaken to determine the relevant properties of Croton megalocarpus seeds as a source of vegetable oil and its prospects as a non-food crop source of biodiesel. C. megalocarpus is a tree indigenous to East Africa which grows up to a height of 35-40. m and produces seeds which contain 40-45% oil on a mass basis. The seeds were examined and properties determined that relate to their transport and storage/handling characteristics. Oil was extracted mechanically from the seeds using a hydraulic press and chemically from the pressing residue using petroleum ether. The combustion quality of the extracted crude vegetable oil such as the gross calorific value, carbon, hydrogen and oxygen content and ash content were then determined. This study indicates that the oil from the C. megalocarpus tree has a strong potential as a source of biodiesel. © 2010 Elsevier Ltd. Source

Doughari J.H.,Modibbo Adama University of Technology, Yola
African Journal of Microbiology Research | Year: 2010

Antimicrobial activity of organic (methanol and chloroform) and aqueous stem back extracts of Erytrina senegalensis against some pathogenic microorganisms was investigated using the filter paper disc diffusion method. Phytochemical studies revealed the presence of saponins, tannins, glycosides, phenols and alkaloids. The extracts demonstrated antimicrobial activity against both bacteria (Staphylococcus aureus, Streptococcus pyogenes, Escherichia coli, Salmonella typhi, Pseudomonas aeruginosa) and fungi (Aspergillus flavus, Aspergillus fumigatus, Candida albicans, Penicillium notatum). For the bacteria, the highest activity (14 mm zone diameter of inhibition) was demonstrated against E. coli and the lowest activity (4 mm zone diameter of inhibition) against S. aureus and P. aeruginosa, while for the test fungi, the highest activity of 8 and 6 mm (zone diameter of inhibition) was demonstrated against C. albicans and A. flavus respectively, and the lowest activity of 4 mm against P. notatum. The methanol extracts demonstrated the highest activity while, the aqueous extracts demonstrated the lowest activity against all the test organisms. The activity of the extracts increased with increase in temperature (4 - 100°C) and acidic pH, but decreased as the pH was adjusted toward alkalinity (pH 8 - 10). The MIC (7.5 - 30 mg/ml) and MMC (8.0 - 30.0) for bacteria, and MIC (7.5 - 40) and MMC (8.0 - 30.0) shows that E. senegalensis stem bark, if further purified can be used to source novel antibiotic substances for drug development against infections such as typhoid fever, urinary tract and wound infections, dysentery and mycotic infections. © 2010 Academic Journals. Source

Osemeahon S.A.,Modibbo Adama University of Technology, Yola
Research Journal of Pharmaceutical, Biological and Chemical Sciences | Year: 2014

In this study, the effect of different types of polyol (PL) on some physical properties of monomethylol urea (MMU) resin is reported. Monomethylol Urea/diethylene glycol (MMU/DG), monomethylol urea/glycerol (MMU/G) and monomethylol urea/polyethylene glycol (MMU/PG) resins were prepared. Some physical properties namely refractive index, moisture uptake, melting point, viscosity, density, elongation at break and formaldehyde emission were investigated. Differences were recorded between the pure MMU and the monomethylol Urea/Polyol (MMU/PL) on one hand and among the different MMU/PL resins on the other hand. The values of viscosity, density, elongation at break, moisture uptake (MMU/G) and refractive index were higher than that of pure MMU resin while those of formaldehyde emission, melting and moisture uptake of MMU/PG and MMU/DG decreased with respect to MMU resin. This result present MMU/PG as the resin with the highest level of flexibility (elongation at break = 400% and melting point = 1600C) compared to the pure MMU moiety. This development will help to address the present problem of hardness associated with pure MMU resin and hence a potential binder for the coating industry. Source

Kareem S.A.,Modibbo Adama University of Technology, Yola
Journal of environmental science & engineering | Year: 2012

Recalcitrant organosulfur compounds such as Dibenzothiophene (DBT) and its derivatives in real petroleum fractions such as diesel cannot be removed by convectional hydrodesulfurization (HDS) treatment using metallic catalysts as well as extremes of conditions of high pressure and temperature. Biodesulfurization was identified as one of the possible routes for the removal of sulfur from middle distillate fractions of petroleum. The desulfurizing bacterium Desulfobacterium indolicum was isolated and subsequently identified by the Department of Botany and Microbiology, University of Lagos, Nigeria. The bacterium exhibited very high desulfurizing ability towards diesel at 30 degrees C and normal atmospheric pressure. The biodesulfurization of diesel by Desulfobacterium indolicum resulted in reduction of sulfur from 166.037 ppm to 33.412 ppm over a period of 72 hours. Gas chromatography analysis with a pulsed flame photometric detector revealed that the peaks of benzothiophene and dibenzothiophene significantly decreased after biodesulfurization. Thus, Desulfobacterium indolicum could effectively desulfurize diesel and therefore, may be a promising biocatalyst for practical biodesulfurization of diesel. Source

Doughari J.H.,Modibbo Adama University of Technology, Yola
African Journal of Biotechnology | Year: 2011

Two Penicillium species namely, Penicillium oxalicum and Penicillium citrinum cultivated by solid surface fermentation method using rice bran homogenized with 0.5% (w/v) (NH 4) 2SO 4 solution as nitrogen source and Whatman no. 1 filter paper (WFP1) as substrate for β-glucanase enzyme production medium were found to show a dense growth. Studies on the enzyme, using soluble cellulose (SC) and methyl cellulose (MC) as cellulose-glucan source and Somogyi titrimetric method, revealed optimum temperature for enzyme activity from the Penicillium species, ranging from 50 to 55°C and thermostability of up to 70°C after 15 to 30 min incubation in sodium phosphate buffer. It was found that the metal ions (0.5 to 5.0 M) namely: Zn 2+, Cu 2+ and Hg 2+ did not enhance β-glucanase activity. Cu 2+ ions reduced the enzyme activity slightly, Zn 2+ ions had no effect, while Hg 2+ completely inhibited β-glucanase activity. β-Glucanase can be produced from some fungal species locally using the abundant agricultural wastes (such as rice bran) as substrates. © 2011 Academic Journals. Source

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