Research Articles in Physical and Chemical Sciences
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Item Analysis of Decomposing Wood Wastes in the Lagos Lagoon using Terminal-Restriction Fragment Length Polymorphism and Illumina Sequencing Platform(NIGERIAN JOURNAL OF TECHNOLOGICAL DEVELOPMENT, 2022-06) Buraimoh, O. M.; Adewumi, G. A.; Akinyemi, N. M.; Amund, O. O.; Ilori, M. O.; Michel Jr., F. C.Indiscriminate disposal of wood shavings and sawdust into the Lagos lagoon usually constitute environmental hazard and varying degree of threats to marine biotic communities. In this study we applied terminalrestriction fragment length polymorphism (T-RFLP) and illumina sequencing of 16S ribosomal RNA gene, to describe the microbial ecology of decomposing wood wastes in the Lagos lagoon, Nigeria. The terminal restriction fragments (TRFs) generated corresponds to over 100 bacterial genera and numerous uncultured bacterial clones. Phylogenetic analysis of the TRFs of 16S rRNA gene sequences and cultured bacterial sequences established genetic relatedness and divergent relationships. T-RFLP in combination with illumina sequencing platform identified bacterial species (Acinetobacter sp., Clostridium sp., Planctomyces sp., Escherichia coli, Pantoea agglomerans, Dyella japonica, Ochrobactrum sp., Prevotella sp., Runella slithyformis, Enterobacter aerogenes, Gordonia amicalis, Klebsiella sp., Thalassospira sp. and Serratia sp.) not previously accounted for in culture-dependent analysis. Bacterial strains such as Ruminococcus flavefaciens, Fibrobacter succinogenes, Simiduia agarivorans, Microbulbifer sp. and Cellulomonas fimi further identified in illumina sequences were found to be involved in the biodegradation of lignin and lignin derivatives. Hence, understanding of the diverse autochthonous microbiota of decomposing wood wastes in the Lagos lagoon is essential in the development of effective biotechnology programme, to tackling the menace of sawdust pollution.Item Nitrilase gene detection and nitrile metabolism in two bacterial strains associated with waste streams in Lagos, Nigeria(Bulletin of the National Research Centre, 2022-05) Ogunyemi, Adewale Kayode; Buraimoh, Olanike Maria; Ogunyemi, Bukola Caroline; Samuel, Titilola Aderonke; Ilori, Matthew Olusoji; Amund, Olukayode OladipoBackground: The use of nitrile compounds is usually high, particularly in chemical industries, which calls for serious concern because of their relevance to the environment. The essential role of nitrilases in the bioremediation of harmful nitriles from environmental wastes cannot be overemphasized. The study aimed to unveil the biodegradative potentials of bacterial strains associated with the degradation of nitrile pollutants. Methods: Bacterial strains capable of utilizing glutaronitrile as the sole source of carbon and nitrogen were isolated from solid waste leachates by a selective enrichment culture technique. The test organisms were grown in mineral salts medium (MSM), and the metabolic products were determined using gas chromatography-fame ionization detection (GC-FID). The nitrilase gene was amplifed by polymerase chain reaction (PCR) and by using appropriate primers. Results: The growth studies showed that the test organisms grew on the two nitriles. The doubling times of 12.16 d and 9.46 d (specifc growth rate, µ=0.082 d−1 , 0.106 d−1 ) were obtained for each pure culture of Bacillus sp. srain WOD8 and Corynebacterium sp. srain WOIS2 on glutaronitrile (as single substrate), respectively. While the same strains had doubling times of 11.11 d and 10.00 d (µ=0.090 d−1 , 0.100 d−1 ) on benzonitrile (as single substrate). However, the mixed culture (comprising the two strains) had doubling times of 7.40 d and 7.75 d (µ=0.135 d−1 , 0.129 d−1 ) on glutaronitrile (as single and mixed substrates), respectively. While doubling times of 8.09 d and 8.71 d (µ=0.124 d−1 , 0.115 d−1 ) were obtained for the same mixed culture on benzonitrile (as single and mixed substrates). Based on gas chromatographic analysis, the residual glutaronitrile concentrations at day 16 for strains WOD8 and WOIS2 were 35.77 g L−1 (72.2%) and 9.30 g L−1 (92.5%), respectively, whereas the residual benzonitrile concentrations for the same strains were 27.39 g L−1 (78.8%) and 13.79 g L−1 (89.2%), respectively. For the mixed culture, residual glutaronitrile and benzonitrile concentrations at day 16 were 13.40 g L−1 (88.5%) and 10.42 g L−1 (91.5%), respectively, whereas for the mixed substrates (glutaronitrile and benzonitrile), 7.21 g L−1 (91.7%) and 4.80 g L−1 (94.2%) of residual glutaronitrile and benzonitrile concentrations were obtained by the same consortium. The gene for nitrilase involved in nitrile degradation was detected in the genome of the bacterial strains. The amplifed nitrilase gene gave PCR products of sizes 1400 bp and 1000 bp, as expected for strains WOD8 and WOIS2, respectively. 4-Cyanobutyric acid (4CBA), glutaric acid (GA), and benzoic acid (BA) were obtained as metabolites following nitrile degradation in vitro.Conclusion: These results revealed that strains WOD8, WOIS2 and the mixed culture (consisting of the two strains) have proven to have the capacity to metabolize nitriles (glutaronitrile and benzonitrile) as the carbon and nitrogen sources. However, the mixed culture had higher nitrile degradation rate as compared to each pure culture of the two test organisms. These results also provide insight into the evolutionary genetic origin of a nitrilase gene that encodes an enzyme that catalyzes nitrile degradation in these strains. Hence, the bacterial strains that harbor this kind of gene may be used as promising biological agents for the remediation of sites polluted with nitriles, thereby opening new perspectives for encouraging data for a bioremediation bioprocessItem A global metagenomic map of urban microbiomes and antimicrobial resistance(Cell Journal by Elsevier, 2021-05-26) Osuolale, Olayinka O.; Danko, David; Bezdan, Daniela; et alWe present a global atlas of 4,728 metagenomic samples from mass-transit systems in 60 cities over 3 years, representing the first systematic, worldwide catalog of the urban microbial ecosystem. This atlas provides an annotated, geospatial profile of microbial strains, functional characteristics, antimicrobial resistance (AMR) markers, and genetic elements, including 10,928 viruses, 1,302 bacteria, 2 archaea, and 838,532 CRISPR arrays not found in reference databases. We identified 4,246 known species of urban microorganisms and a consistent set of 31 species found in 97% of samples that were distinct from human commensal organisms. Profiles of AMR genes varied widely in type and density across cities. Cities showed distinct microbial taxonomic signatures that were driven by climate and geographic differences. These results constitute a highresolution global metagenomic atlas that enables discovery of organisms and genes, highlights potential public health and forensic applications, and provides a culture-independent view of AMR burden in cities.Item Antioxidant activities and glycemic indices of ice creams enriched with orange (Citrus sinensis) and shaddock (Citrus maxima) peels and effects on rat lipid profiles(Wiley, 2021-05) Ademosun, Ayokunle Olubode; Oboh, Ganiyu; Ajeigbe, Olufunke FlorenceThis study evaluated the effects of ice creams produced from blends of orange (Citrus sinensis) and shaddock (Citrus maxima) peels on the blood lipid profile, glycemic index, and antioxidant indices in the liver and heart of rats. Formulated ice cream was produced at a different proportion of citrus (orange and shaddock) blends and fed to rats for 28 days. The result showed that the formulated ice cream enriched with citrus peels blends caused a significant increase in high-density lipoprotein-cholesterol level in the plasma and antioxidant status in the liver and heart homogenates, decreased the glycemic index, concentration of total cholesterol, triglycerides, and low-density lipoprotein in the plasma as against rats fed on plain and commercial ice creams. To conclude, the use of ice creams from blends of orange and shaddock peels could serve as a functional food for weight reduction, glycemic index, management of lipid-related diseases, and prevention of oxidative stress-related complications in the liver and heart. Practical applications The consumption of ice creams has increased in many parts of the world. However, there have been limited efforts aimed at improving the medicinal properties of frozen dairy products. Hence, these ice creams could be produced on a large scale under regulated condition since they have improved medicinal properties which would be a good option for preventing/combating degenerative conditions and their related complications.Item Laccase nanoparticle: Synthesis, characterization, entrapment in alginate beads and application in the biodegradation of Bisphenol A(Materials Science and Engineering Conference Series, 2021-05) Adedeji, Ademakinwa N.; Ojo, Abidemi; Erasmus, Mariana; Agunbiade, Mayowa, O.Laccase nanoparticles (LNP) were synthesized by desolvation of the enzyme with ethanol and cross-linking with glutaraldehyde. LNP was characterized via scanning electron microscopy (SEM) and then entrapped in alginate beads for the biodegradation of bisphenol A (BPA). The stability of the immobilized LNP (iLNP) to heat inactivation was also investigated. The iLNP retained about 53±4.7% of its initial activity after 7 cycles of catalysis. The iLNP was stable to thermal inactivation at 40-70°C as obtained from its kinetic and thermodynamic parameters. The iLNP removed 80 mg/L BPA from solutions with a biodegradation efficiency (BE) of 92% after 1 h. Repeated use of the iLNP in BPA removal resulted in a BE of 75% after 7 cycles of catalysis. iLNP serves as a novel biocatalyst in the bioremediation of pollutants such as BPA, and its thermostable characteristics make it useful for other biotechnological applicationsItem Antioxidant activities and glycemic indices of ice creams enriched with orange (Citrus sinensis) and shaddock (Citrus maxima) peels and effects on rat lipid profiles(Wiley, 2021-05) Ademosun, Ayokunle Olubode; Oboh, Ganiyu; Ajeigbe, Olufunke FlorenceThis study evaluated the effects of ice creams produced from blends of orange (Citrus sinensis) and shaddock (Citrus maxima) peels on the blood lipid profile, glycemic index, and antioxidant indices in the liver and heart of rats. Formulated ice cream was produced at a different proportion of citrus (orange and shaddock) blends and fed to rats for 28 days. The result showed that the formulated ice cream enriched with citrus peels blends caused a significant increase in high-density lipoprotein-cholesterol level in the plasma and antioxidant status in the liver and heart homogenates, decreased the glycemic index, concentration of total cholesterol, triglycerides, and low-density lipoprotein in the plasma as against rats fed on plain and commercial ice creams. To conclude, the use of ice creams from blends of orange and shaddock peels could serve as a functional food for weight reduction, glycemic index, management of lipid-related diseases, and prevention of oxidative stress-related complications in the liver and heart. Practical applications The consumption of ice creams has increased in many parts of the world. However, there have been limited efforts aimed at improving the medicinal properties of frozen dairy products. Hence, these ice creams could be produced on a large scale under regulated condition since they have improved medicinal properties which would be a good option for preventing/combating degenerative conditions and their related complications.Item The influence of primary radio climatology parameters on radio refractive index over the African region: a 30-year satellite study(Journal of Physics: Conference Series, 2021) Dada, J B; Adedayo, K D; Adediji, A T; Ajewole, M OIn the lower part of the atmospheric boundary layer, structure of the radio refractive index plays a vital role when planning and designing microwave communication link. The effects of primary radio climatic parameters on radio wave propagation at UHF and microwave frequencies are crucial in studying radio refractive index. 1951 to 1980 satellite data has been used to investigate the mean values of both the primary radio climatic variables and surface radio refractive index over the Africa. The mean value of water vapor pressure, temperature and pressure ranges from 3-23 mbar, 284-302 K and 800-1000 mbar respectively across Africa. The high values of water vapor pressure around the Coastal and Rainforest reduce towards the Savanna and Steppe region (semi-arid). The mean variation value of surface refractivity over Africa ranges from 160 - 340 N-units. The refractivity values in larger part of the savanna range between 250 – 280 N-units.Item Ocimum Gratissimum Extract As potentials Eco-Friendly Inhibitor for Aluminum Alloy in Hydrochloric Acid(Chemical Society of Nigeria, 2010) Nkiko, Mojisola O.Item Adoption Kinetics and Thermodynamics of Malachite Green Onto Chitosan / Sodium Citrate Beads(Ife Journal of Science, 2013) Bamgbose, Janet; Bamigbade, A.A.; Nkiko, Mojisola O.Item Role of mixed surfactants on the oxidation of malachite green by nitrite ions(Journal of American Sciences, 2018) Bamgbose, Janet; Ede, Chukunedum; Bamigbade, Akeen; Abdullahi, Ndzi; Nkiko, Mojisola O.Item Effect of Inositol Hexaphosphate on the Azide Binding Reactivity of Mouse Methaemoglobin(International Journal of Science and Technological Research, 2007) Nkiko, Mojisola O.; Demehin, A. A.; Ogunmola, G. B.Methernoglobin (metl—lb) reactswith neutral and negative ligands because of the availability of a net positivecharge to form complexes. This reaction involves the replacement of the water molecules at the sixth Coordinated positionItem Effect of Electrodeposition Mechanism and α-Si3N4/ZrBr2 Doped Composite Particle on the Physicochemical and Structural Properties of Processed NiPZn Coatings on Mild Steel for Advance Application(Key Engineering Materials (Volume 900), 2021-09) Fayomi, Ojo Sunday Issac; Ayodeji, Sode Adedamola; Anyanwu, Benedict Uche; Nkiko, Mojisola O.; Dauda, Khadijah TolulopeNi-P-Zn nanocomposite coatings were plated on mild steel surface from sulphamate rich bath containing (α-Si3N4 and α-ZrBr2) nanoparticle produced via electrodeposition process. The compositions of the particulate were varied from 0 to 10 wt% with time variation between 10 to 25 min after ascertaining other optimum parameters. The crystal evolution and morphological quantification were examined using scanning electron microscope supported with energy dispersive spectroscopy. The corrosion degradation in an acidic and alkaline environment was considered and compared to establish the suitability and extents of the corrosion vulnerability of deposited coatings. The surface flake crystal identified on the microstructural properties show the presence of compositional constituent and disperse particle of α-Si3N4 and α-ZrBr2. Finally, corrosion properties show a resilient crystal surface stability in the presence of chloride and sulphate ion with a remarkable surface film still retained at the bulk interface. This study has confirmed that α-Si3N4 and α-ZrBr2 composite coating can be used for structural development and corrosion improvement in the presence of active ions. Keywords: Nanomaterials, Structure, Corrosion, Prevention, CoatingsItem Effect of ZrB2 Functionalized Nanoparticles Growth on Microstructural and Corrosion Resistance on Mild Steel through Electrodeposition Route(Key Engineering Materials, 2021) Fayomi, Ojo Sunday Issac; Nkiko, Mojisola O.; Dauda, Khadijah Tolulope; Oluwasegun, Kunle MichaelIn other to have a better performance of Ni-P-Zn multifunctional applications, crystallite-like Ni-P-Zn-ZrB2 composite was actively fabricated by electrodeposition principle. The corrosion, structural evolution and surface active phenomena were investigated by various techniques. The influence of ZrB2 particulate on the morphology and corrosion properties was examined. The outcomes show an inclusive flower-like doped ZrB2 phase constituent and is uniformly distributed Ni-P-Zn-ZrB2 improved strengthening effect. The corrosion progression of the developed metal alloy was compared with other coating matrix from 10-25 minutes interval. The integration of ZrB2 on Ni-P-Zn phase especially for 25 min deposits significantly enhances corrosion resistance due to good grain refinement. Keywords: Ni-based composite, electrodeposition, time difference, coating, corrosionItem Review of metal protection techniques and application of drugs as corrosion inhibitors on metals(IOP Conference Series: Materials Science and Engineering, 2021-04) Nduma, R.C .; Fayomi, O.S.I.; Nkiko, Mojisola O.; Inegbenebor, A.O.; Udoye, N.E.; Onyisi, O.; Sanni, O.; Fayomi, J.The inability of metals to resist degradation as a result of corrosion remains a unique global problem that depend on different metals for daily operations. Therefore, knowing the appropriate method to use is a key to ameliorate corrosion effect on metals. Green inhibitors serve as a modern, cheaper and environmentally favorable method to retard the effects of corrosion. Drugs are corrosion inhibitors which can reduce the action of corrosion without being hazardous to the environment as they are synthesized from natural products. The review studies the metal protection techniques and the use of drug as corrosion inhibitors. The importance of copper as a useful metal as good corrosion resistance due to inherent properties alongside its malleability was also discussed.Item Evaluation of the Industrial Potential of Pentachletra Mycrophylla Seed(lntegrated Journal of Science and Engineering, 2000) Taiwo, E. A.; Nkiko, Mojisola O.; Adekoya, T. S.Item Experimental studies and influence of process factor on zinc-nickel based coating on mild steel(Taylor & Francis: Advances in Materials and Processing Technologies, 2021-03) Fayomi, O.S.I.; Sode, A.A.; Anyanwu, B.U.; Ayoola, A.A.; Nkiko, Mojisola O.; Oluwasegun, K.M.; Alkhuele, D.O.; Ighravwe, D.E .Sulphate-rich electrolytic bath containing ZnSO4.7H2O in NiP solution was used to develop coating with Ni-P-Zn matrix under optimised process parameter. The major considerations are to examine the factor variance and the effect of varying time parameter between 10, 15, 20 and 25 min on the developed coating. Wear loss evolution was examined using reciprocating sliding wear tester with a force of 10 N and 20 N. The microhardness behaviour was examined using durascan microhardness tester with diamond indenter. The change in the structural build-up and the corrosion performance trend was observed using a scanning electron microscope enhanced with energy dispersive spectroscopy and potentiodynamic polarisation route. From the result we observe that time-dependant factors impact maximally on the crystal growth which rightly influences the coating hardness performance. For wear performance, the counter with external forces couldn’t penetrate wholly into the lattice of the developed coating due to the resilient formation of stable flakes. The microstructure formation shows stable dispersed crystal build-up and homogeneous growth. An excellent corrosion resistance characteristic was noticed with Ni-P-Zn-25 min matrix.Item Infusing Entrepreneurship Education into Science and Technology Training in Nigeria: Issues and Strategies(Faculty of Basic and Applied Sciences, Elizade University, 2019-06) Nkiko, Mojisolascience and Technology remains unarguably the fulcrum on which advancement progress and improvement in all sectors of any economy revolves while entrepreneurship through learned ingenuity galvanizes and optimizes the opportunities, innovations, skills and competences derivable from the former for product development, commercialization and wealth creation. The growing incidence of youth unemployment and general poverty level in Nigeria calls for a serious rethinking of the capabilities and capacity of the graduates of Science and Technology. It is against this background that the paper examined entrepreneurship, science and Technology as major drivers of the economy and n,1tional development. It reviewed the current system of education and its inherent inadequacies that preclude practical application and foray into entrepreneurship. The paper distilled practices prevalent in emerging economies of Asian countries with a view to extrapolating such lessons as a model of adoption for the crystallization of sustainable entrepreneurship in the Nigerian Science and Technology education. The issues of curriculum, pedagogy, manpower, infrastructure, attitudes, orientation and funding were discussed as critical preconditions for the emergence of effective entrepreneurship in Science and Technology. The paper concluded that the entrenchment of entrepreneurship in Science and Technology education would rekindle the interest of the millennia in the enrolment of the disciplines. It would result in a departure from theoretical knowledge to empowerment for wealth creation and practical solution · to societal problems. Some recommended solutions include establishment of incubation hubs, industry partnership, strengthening of compulsory internship, international exchange programmes, product development and commercialization policies, special legislations and corporate social responsibility initiatives.Item Assessment of groundwater pollution near Aba-Eku municipal solid waste dumpsite(Springer Nature : Environ Monit Assess, 2019-10) Aromolaran, Olukemi; Fagade, Obasola E.; Aromolaran, Olawale K.; Faleye, Emmanuel T.; Faerber, HaraldMunicipal solid waste (MSW) dumpsite constitutes a major anthropogenic point source of leachate contamination to the ambient groundwater and poses a significant threat to the geo-ecosystem. This study investigated the pollution of groundwater by leachate emanating from Aba-Eku MSW dumpsite in Ibadan, Nigeria, using bacteriological, hydrochemical, and geophysical techniques. There is a diversity of bacteria in the leachate and the dominant phyla being proteobacteria (83%) and firmicutes (17%). The mean concentrations (mg/L) of Mn, Fe, Al, Cu, Mo, and Cr in the leachate samples were above the World Health Organization wastewater discharge limits. The hydrochemical parameters of the groundwater samples around the dumpsite were generally within the permissible limits, except for K and Cl−; which invariably indicate major inputs from water-rock interaction and minor contributions from the dumpsite. Three geoelectrical layers were indicated from the vertical electrical sounding data, which are the topsoil, the lateritic clay layer, and the weathered basement. Low resistivity values of 5–33 Ωm and 3–24 Ωm were obtained within 2mand 5.5mdepths for the topsoil and the lateritic layer, respectively; while the 2-D subsurface model reveals leachate plume beyond 5 m. Although the MSW leachate is heterogeneous, the hydrochemical data show that the aquifer around the dumpsite has not been seriously polluted with the leachate, but there is a continuous percolation of leachate into the soil subsurface, based on the geophysical findings. Discontinuing waste dumping and groundwater extraction, which would over time reduce the leachate plume, aremeasures to enhance the groundwater quality in the area.Item Integrating Resistivity Techniques for Optimum Groundwater Exploration and Development within a Hotel Facility in Osogbo, Southwestern Nigeria(J. Appl. Sci. Environ. Manage., 2021-02) OJO, A;; BABAFEMI, E;; FALEYE, E;; SHADO, O.This work is an attempt to combine dipole-dipole profiling and vertical electrical sounding techniques of electrical resistivity methods to investigate the groundwater potential within the premises of a 3-star hotel facility in Osogbo, Nigeria by delineating the geoelectric layers, delineating the low resistivity layers, determining the lithologies and hence, delineating the groundwater bearing zones. The five vertical electrical sounding data were collected along two pre-surveyed dipole-dipole traverses at right angle to each other beside the fences of the premises using the ABEM SAS 300c terrameter. The observed data were interpreted quantitatively using curve matching and computer-assisted iteration method using the WinResist and Dipro software. The results of the inversion show that the lithology comprises of the top soil and an intermittent sequence of sand and lateritic clay having varying resistivity and thickness. The aquiferous layer was observed to be located at a depth of 23 m to 25 m due to the low resistivity and high thickness of the aquiferous layer. The result of the 2-D imaging closely correlates with the result of the vertical electrical sounding. Thus, combining these techniques in groundwater investigation has achieved similar result as the Werner technique and has reduced ambiguity and error in positioning for drilling.Item Fig leaves varieties reduce blood pressure in hypertensive rats through modulation of antioxidant status and activities of arginase and angiotensin-1 converting enzyme(Springer Link : Comparative Clinical Pathology, 2021-05) Ajeigbe, Olufunke F.; Oboh, Ganiyu; Ademosun, Ayokunle Olubode; Oyagbemi, Ademola AdetokunboThe medicinal application of sandpaper leaves in the management of hypertension has been reported with very little knowledge on the variety with better anti-hypertensive properties. Hence, this study seeks to compare phenolic content and the effect of some varieties of sand paper leaves (Ficus spp.), namely, Ficus exasperata (FE), Ficus asperifolia (FA), Ficus mucuso (FM) and Ficus capensis (FC) on the systolic and diastolic bood pressures (SBP and DBP), angiotensin-1-converting enzyme (ACE), and arginase activities and antioxidant status in L-NAME induced hypertensive rats. The animals were divided into eleven groups (n = 6): normotensive control rats, hypertensive rats, hypertensive rats treated with atenolol (10 mg/kg/day), hypertensive rats treated with 2.5% and 5% FE, FA, FM, and FC extract inclusive diet respectively. There was a significant rise (p < 0.05) in the systolic and diastolic blood pressures, ACE and arginase activities, and antioxidant status in the hypertensive rats. However, there were reductions in the SBP, DBP, ACE, and arginase activities and increase in the antioxidant status of the rats fed with the Ficus leaves. FM had the highest phenolic (91.09 mg/100 g) and flavonoid content (43.35 mg/100 g). FA showed the best anti-oxidant property, while FC showed the strongest inhibition of ACE and arginase activities.