JOURNAL OF SCIENCE RESEARCH

Determination of the pKa values of some selected aromatic amines and naturally occurring compounds in polar and non-polar solvents at 25oC

Eugene-Osoikhia — 2021-07-15

Ionisation constant is a measure of the strength of acids and bases and is expressed in terms of the pKa of conjugate acids
and bases. The pKa of naturally occurring khivorin, 7-keto-khivorin and some aromatic amines were measured in chloroform,
toluene, 50% ethanol-methanol, 50% ethanol-water and 75% ethanol-methanol mixture at 25oC by potentiometric titration.
The pKa values obtained are 3.23 for khivorin in toluene and 1.20 for 7-ketokhivorin in chloroform which demonstrate their
acidic nature. The aromatic amines: indole and 4-dimethylaminopyridine have a higher pKa values in 50% ethanol-water
solvent compared to their values in ethanol-methanol solvents. 3-methylindole and para-toluidine have a higher pKa
values in 50% and 75% ethanol-methanol solvents than in ethanol-water solvent. The higher pKa values of indole and 4-
diemthylaminopyridine in 50% ethanol-water signifies the best medium at which the strength of these amines could be
determined; whereas p-toluidine is best determined in 50% ethanol-methanol and 3-methylindole in 75% ethanol-methanol
mixture.

Bioremediation of spent diesel oil contaminated-soil by Pleurotus ostreatus (Jacq. Fr) P. Kumm

Onakpharkpote E. E. — 2021-07-15

Soil contamination with petroleum products has gained much attention globally in the last decade owing to their toxic
effects on the ecosystem. Remediation of such contaminated-soil before crop cultivation becomes imperative. In this
study, the potential of Pleurotus ostreatus to biodegrade spent diesel oil contaminated-soil for a period of two months
was investigated. Four kilogram of top soil was contaminated with varying compositions (5, 10 and 15% w/v) of spent
diesel oil was inoculated with 50 g of P. ostreatus, incubated at 28 ? 2oC in triplicates and analyzed for some physico-
chemical parameters before and after incubation. The overall effect of the fungus on spent diesel oil contaminated-soil and
straw levels showed that the highest nutrient content was at 15% contamination level with 10.8%, 17.59%, 1.12%, 1.14
cmol/kg, 8.88 cmol/kg and 1.78 cmol/kg respectively for organic carbon, organic matter, total nitrogen, potassium, calcium
and magnesium contents except for phosphorus with the highest value of 18.12 mg/kg observed at 5% contamination
level. Also, 15% spent diesel oil contaminated-soil had the highest overall heavy metal reduction with 8.45, 7.43, 5.79,
42.81, 5.78 and 3.18 mg/kg respectively for Cd, Cr, Ni, Pb, Cu and Zn. At each incubation period, the pH of each contaminated-
soil ranged from 7 to 8. This improvement of soil nutrient content as well as reduction in the heavy metal contents of the
soil could be an indication of degradation of organic and inorganic contaminants by P. ostreatus.

Air and heavy metal pollution around a steel foundry in Ogijo, Ogun State, Nigeria

Olayinka O. O. — 2021-07-15

A whole range of bye-products from industries such as steel plants and metal processing facilities create serious pollution
to the environment, with negative health implications. In this study, we examined environmental pollution around African
Steel Foundry in Ogun State, Nigeria. Air sampling was carried out using Land Duo Multi gas monitor to determine air
pollutants such as Total Suspended Particulate Matter (TSP), Carbon monoxide (CO), Carbon dioxide (CO2), Nitrous oxide
(NO), Nitrous oxide and Nitrogen dioxide (NOx), Hydrogen sulphide (H2S) and Sulphur dioxide (SO2). Thirty soil and plant
samples were collected from Steel Foundry. Concentrations of selected heavy metals (Fe, Cu, Cd, Ni and Pb) were
determined in both soil and plant (cassava, pawpaw and maize leaves) samples using an Atomic Absorption Spectroscopy
(AAS). The results show that total suspended particulate matter (TSP) ranged from 123.46 ?gm–3-353.74 ?gm–3, while CO,
CO2, NO, NOx, H2S, and SO2 ranged from 3.20-13.33 ppm, 3.55-5.04 ppm, 1.36-5.69 ppm, 2.02- 8.50 ppm, 0.96-1.93 ppm and
1.63-3.96 ppm respectively. Some of these values exceeded the USEPA guideline limit of clean air. Mean concentrations of
Fe, Cu, Cd, Pb and Ni found in the plants and soils were below WHO guideline limit of heavy metals. The results revealed
the high concentration TSP, NO, and SO2 which may lead to health risk after long time of exposure and also accumulation
of these metals overtime may lead to contamination of the agricultural soils which eventually pose threat to organisms that
feed on the plants.

Facies model building of integrated multiscale data in Dn-Field, Onshore, Niger Delta, Nigeria

Nton M. E. — 2021-07-15

This study employs 3D Post-Stack Time-Migrated seismic data from the DN-Field, within the Coastal Swamp depobelt of
the Niger Delta in predicting lithofacies and fluvial facies of OVK-1 sand bodies in the Agbada Formation, as a tool to
identify new drillable prospects. A lithofacies model for OVK-1 reservoir sand body was generated after upscaling using
Most Of, as the averaging method. Calibrated by fluvio-facies at the well locations, channel sands were identified in OVK-
1 reservoir interval using Stochastic Sequential Indication Simulation (SSIS) algorithm. Based on lithofacies, fluvial facies
and biofacies analyses, a terrigenous and shallow fluvio-deltaic fill within a lowstand system tract was evident. Petrophysical
properties including porosity, volume of shale and effective porosity were upscaled, guided by facies model and then
Stochastic Gaussian Simulation (SGS) algorithm was used to produce the model. Porosity model predicted sand layers
having maximum porosity of 27.5% which implied very good reservoir potential. However, the volume of shale model with
values from 0.45 to 0.50 incorporates silt and clay and indicates marginal reservoir potential. The study identifies four
potential reservoir intervals with thickness ranging from 9.1 to 38.5 m. The effective porosity in OVK-1 ranges from 0.10 to
0.30 and identified fluvial facies such as floodplain, channel sand, levee and crevasse splay sand. Facies model show a
good sand distribution with minor shale localized in the western part of the Field. The central part of the model has good
reservoir qualities, evident by low volume of shale values and high porosities. This study helps to identify a potential
unexplored drillable prospect on OVK-1 sand body south-west of DN-2 well. Successful drilling of the identified prospect
could increase the reserve of the Field.

Depositional environment and reservoir quality appraisal of offshore 'K-Field', Niger Delta, Nigeria

Boboye O.A. — 2021-07-15

This study attempts to evaluate the hydrocarbon reservoir and depositional trend of ‘K- Field’ via suites of wireline logs.
This is to identify, correlate the sand bodies and evaluate their petrophysical attributes with a view of understanding their
variation as itaffects the reservoir, hydrocarbon prospect and productivity in the field, and to determine the
palaeoenvironment of the lithofacies. Six sand bodies were identified and correlated across three wells. Zones of sand
level with water saturation < 0.50 were the hydrocarbon bearing. The various hydrocarbon reservoirs determined are six
(W-7), four (W-2) and three (W-11) respectively. The average petrophysical properties of the reservoirs range from 19% to
25%, 54.84 md to 1159.90 md, 20% to 42% and 58% to 80% for porosity, permeability, water saturation and hydrocarbon
saturation respectively. The porosity and permeability range from good to excellent. The identified reservoirs show high
movable oil saturation (MOS), low residual oil saturation (ROS) and favourable values of movable hydrocarbon index (Sw/
Sxo< 0.7). The field has both oil and gas hydrocarbon with the Gas Oil Contact (GOC), Oil-Water-Contact (OWC), Oil-
Down-To (ODT) and Gas-Down-To (GDT) contact types. The cross plot of water saturation and porosity revealed that the
grain sizes of the sand bodies range from coarse to very fine. Bulk Volume Water (BVW) cross plot indicated that most of
the reservoirs are heterogeneous and not at irreducible water saturation. The log facies recognized suggest a palaeo-
depositional environment of basin plain, crevasse splay, prograding and transgressive marine shelves.

Effect of inositol hexakisphosphate on sulphydryl reactivities of low (cat) and high (human) oxygen affinity haemoglobins

Okonjo, K. O. — 2021-07-15

The effect of organic phosphate binding on the reactivities of low-affinity cat haemoglobin in comparison to high-affinity
human haemoglobin was determined. Kinetics of the reaction of the CysF9[93]? sulphydryl groups in both haemoglobins
with 5,5?-dithiobis(2-nitrobenzoate) – DTNB – which has been linked to oxygen binding, was used to probe this effect.
Plots of the pseudo-first order rate constant, kobs, as a function of the DTNB concentration were linear and had positive
intercepts. This is indicative of the fact that the organic phosphate used, inositol hexakisphosphate (inositol-P6), does not
abolish reversibility in both haemoglobins. Cat haemoglobins gave simple pH-dependence profiles for the apparent
second order forward rate constants, kF. The presence of inositol-P6 increased kF, hence reactivity, by two-fold throughout
the experimental pH range for cat oxyhaemoglobin. In contrast, inositol-P6 decreased kF for human oxyhaemoglobin.
Around the physiological pH, kF decreased from a maximum value of 31.9 ? 0.6 mol-1dm3s-1 to 26.7 ? 0.3 mol-1dm3s-1 for
human haemoglobin, while it increased from a minimum of 17.2 ? 0.4 mol-1dm3s-1 to 20.6 ? 0.6 mol-1dm3s-1 for cat minor
oxyhaemoglobin.

Biosorption of cadmium (II), copper (II) and lead (II) ions by citric acid modified and unmodified cocoa pod shell: Equilibrium, kinetics and thermodynamics

Ayedogbon, A. S. — 2021-07-15

Chemical modification of biosorbent is a common practice in wastewater treatment when using adsorption technology.
Thioglycollic acid has been used for the modification of cocoa pod without any significant improvement in its adsorption
capacity for lead, cadmium and copper. This study is aimed at improving the sorption of these metal ions from aqueous
solution using citric acid as the modifying agent for cocoa pod shell. The dried cocoa pod shell was ground and reacted
with citric acid according to the method in the literature. Batch adsorption studies were conducted to examine the
influence of pH, temperature, initial metal ion concentration; sorbent dose and contact time on the biosorption of Pb2+,
Cu2+and Cd2+ions by modified and unmodified cocoa pod shell. Langmuir, Freundlich, Temkin and Dubinin-Radushkevich
models were used for fitting the equilibrium data. The amount of metal ion sorbed was determined using flame atomic
absorption spectrophotometer (FAAS). The result for the adsorption of the metal ions under varying pH showed that
sorption was pH dependent. The trend in biosorption was in the order of Cd2+> Cu2+> Pb2+ on unmodified cocoa pod shell
(UCPS); while the trend in biosorption of the ions onto modified cocoa pod shell (MCPS) was in the order of
Pb2+ > Cu2+> Cd2+. The amount of Pb2+ adsorbed increased from 4.62-33.56 mg/g after modification as shown by values
obtained using the Langmuir equation to fit the biosorption data. Langmuir isotherm gave R2 values which shows that it
satisfactorily describe the biosorption process for Pb2+, Cu2+and Cd2+ ions on UCPS and MCPS. The kinetics of the
sorption process was best described by the pseudo-second order kinetic model (R2>0.9922). Thermodynamic parameters
showed that biosorption process was feasible and spontaneous for Pb2+, Cu2+and Cd2+ions onto UCPS and MCPS. The
process is exothermic for Cu2+ and Cd2+ ions; but endothermic for Pb2+. This study has shown that citric acid modified
cocoa pod shell is a good biosorbent especially for Pb2+ ions

Bioremediation of spent diesel oil contaminated-soil by Pleurotus ostreatus (Jacq. Fr) P. Kumm

Oyetunji, O. J. — 2021-07-15

Subsistence of four bacteria isolated from Nigerian aquaculture farms on oxytetracycline

Adekanmbi, A. O. — 2021-07-15

The ability of 147 oxytetracycline (OTC)-resistant bacteria isolated from aquaculture ponds in Ibadan, Nigeria, to subsist
on OTC as a source of nutrient for growth was investigated in this study. Four bacteria identified by 16S rDNA sequencing
as Bacillus pumilus Aa8, Bacillus pumilus Ab11, Stenotrophomonas maltophilia Ng7 and Klebsiella pneumoniae Nf6
utilised 4.8, 13.1, 16.5 and 19.0 % of the OTC supplied in the growth medium in 72 hours with degradation rates of 8.0, 21.8,
27.5 and 31.7 ?g/day respectively. The results showed that bacteria capable of subsisting on tetracycline (TET) antibiotics
are present in the environment. However, the risk of possible transfer of resistance determinants to other environmental
bacteria by these strains is a disincentive to their use in the clean-up of antibiotic contaminated ecosystems.

Physical and biochemical characterisation of bacteriocins produced by three Lactobacillus species

Odeniyi O. A. — 2021-07-15

The bacteriocins produced by Lactic acid bacteria (LAB) species (L. plantarum L2, L. paraplantarum L5 and L. pentosus
L11) were characterized with respect to their sensitivity to heat, pH, cations, surfactants, inhibitors and papain. The
activity of bacteriocin produced by L. plantarum L2 and L. pentosus L11 was stable at 100?C for 20 minutes while 87.5%
of the activity of L. paraplantarum L5 bacteriocin was retained. The bacteriocin activity of L. pentosus L11 and
L. plantarum L2 was unaltered after 15 minutes autoclaving while there was a reduction in that of L. paraplantarum L5
(6.25%). The bacteriocin activity of the LAB strains at pH 3 to pH 5 was higher than the values of the control and pH 3
supported the highest activity in all the isolates. Tween 80 boosted all bacteriocin activity while 5 mM-10 mM of benzoic
acid augmented bacteriocin activity of L. plantarum L2. The activity of L. pentosus L11 bacteriocin was unaffected at all
concentrations of ammonium ion (NH4
+) used. At 5 mM concentrations of Ca2+, the activity of the three Lactobacillus
bacteriocins were slightly increased (10%). Crude papain and three fold aqueous dilutions of crude papain completely
inhibited bacteriocin activity. The properties exhibited by these bacteriocins are an indication that they and their producing
strains may find applications in industrial processes.

A comparative analysis of the binding site of Plasmodium falciparum histone deacetylase-1 and human histone deacetylase-8

Odozi N. W. — 2021-07-15

Histone deacetylases (HDACs) are a family of enzymes involved in the modulation of mammalian cell chromatin structure,
regulation of gene expression, DNA repair, and stress response. The histone deacetylase enzymes Plasmodium falciparum
histone deacetylase-1 (PfHDAC-1) and human histone deacetylase-8(hHDAC 8) have been identified as novel targets for
development of antimalarial and antitumor drugs respectively. Homology models of PfHDAC-1 and hHDAC 8 were
generated from the crystal structures of HDAC8 and HDLP and IT64 respectively using a restraint guided optimization
procedure involving a combination of the Optimized Potentials for Liquid Simulations and the Generalized Born Surface
Area (OPLS/GBSA) potential setup. The models were validated using protein structure validation tools. Comparative
analysis of their binding sites was also carried out to identify their topology and residue interaction that could be utilized
in developing PfHDAC-1 specific inhibitors.

Depositional environment and reservoir quality appraisal of offshore ‘K-Field’, Niger Delta, Nigeria

Akinsebikan, O. A. — 2021-07-15

Palyno-environmental study of the Araromi-1 Well, eastern Dahomey Basin, south-west Nigeria

Amodu O. I — 2021-07-15

The exploration of many inland basins in Nigeria for their hydrocarbon potential is important to maintain her position in
the global world oil market. A total of 23 core samples extracted from Araromi-1 Well, Eastern Dahomey Basin, south-west
Nigeria, were carefully studied through lithostratigraphy and palynology with a view to determining the lithological
sequence, relative age, palynological zone and paleo-environments of deposition. The lithological characterisation revealed
a wholly shale unit with thin layer of clay towards the top of the well. A total of 58 palynomorphs were recovered and this
indicates well preserved samples with abundant and highly diverse pollen, spores and dinoflagellate cysts. The microfloral
assemblages include abundant zonocostites ramonae, monoporites annulatus, retitricolporites irregularis, monocolpites
marginatus, acrostichum aureum, cyathidites minor, cyathidites sp, laevigatosporites sp and proxapertites cursus.
Abundant quantities of dinoflagellate cysts particularly palaeocystodinium australinium, cerodinium diebeli,
leiosphaeridia sp, palaeocystodinium sp, seleiropemphix homotryblium oceaniclum, odontochitina operculata,
achromorphaera ramulifera and spiniferites sp. were recovered. Common deep water indicator, microforaminiferal wall
linings was also recorded. The well falls within just a zone, P100 to P200, characterized by the occurrence of paleocystodium
australinium, cerodinium diebeli and odontochitina operculata dated Late Maastrichtian to Late Paleocene.
Paleoenvironmental deductions were based on the relative abundance of freshwater swamps pollen and spores, diagnostic
dinoflagellate cysts and deep marine indicator inferring brackish to deep marine setting.

Structural equation modelling of academic performance in statistics degree programme: A case study of University of Ibadan

Adejumo, N. A. — 2021-07-15

This paper is concerned with the structural equation modelling of the academic performance in Statistics degree programme.
Structural equation modelling is a class of methodologies that represent hypotheses about variances and covariances of
observed data in terms of structural parameters defined by a theoretical model. It takes a confirmatory approach to the
multivariate analysis of structural theory which specified the causal relations among the multiple observed variables. The
causal pattern of intervariable relations within the theory was specified a priori. Structural equation modelling evaluated
two models – the measurement model and the structural model. The measurement model related observed responses or
indicators to latent variables (confirmatory factor analysis), while the structural model specified relations among latent
variables (path analysis). The direct and indirect effects of personal factor, psychological factor, institutional/environmental
factor, family characteristics, social and religious factor on the academic performance of students were studied. The
academic performance of students remains a top priority for students, parents, educators, researchers, administrators
(management) and government. The extent to which the theoretical model is supported by sample data collected from
undergraduate students of the Department of Statistics, University of Ibadan, was determined. There were 37 observed
variables and 7 latent variables. The result indicated that the attitude of students towards learning had positive direct
impact on academic performance, while psychological factor had negative influence on academic performance. Also, the
structural equation model analysis with four basic fit indices suggested a reasonable model-data fit.

Effect of inositol hexakisphosphate on sulphydryl reactivities of low (cat) and high (human) oxygen affinity haemoglobins

Olatunde A. M. — 2021-07-15

Biosorption of cadmium (II), copper (II) and lead (II) ions by citric acid modified and unmodified cocoa pod shell: Equilibrium, kinetics and thermodynamics

Alabi A. H. — 2021-07-15

Physical and biochemical characterisation of bacteriocins produced by three Lactobacillus species

Olabode, T. P. — 2021-07-15

Determination of the pKa values of some selected aromatic amines and naturally occurring compounds in polar and non-polar solvents at 25oC

Eugene-Osoikhia T. T. — 2021-07-15

Facies model building of integrated multiscale data in Dn-Field, Onshore, Niger Delta, Nigeria

Arigbe, O. D. — 2021-07-15

A comparative analysis of the binding site of Plasmodium falciparum histone deacetylase-1 and human histone deacetylase-8

Odozi, N, W. — 2021-07-15

Effects of crude oil contaminated-soil on the germination and growth of cowpea Vigna unguiculata (L.) Walp

Odiwe, A. I. — 2021-07-15

A greenhouse experiment was conducted to investigate the germination and growth response of cowpea (Vigna unguiculata
(L.) Walp) to soils contaminated at different concentrations of crude oil. This was done with a view to access the impact
of crude oil pollution on growth and nutrient content after harvest. The contaminated crude oil polluted soils were
prepared at different concentrations of 0.0, 10.0, 20.0, 30.0, 40.0 and 50.0 (w/v) on 5 kg each of air-dried soil collected from
the Obafemi Awolowo University Biological Garden rich in organic matter. Each treatment was replicated three times and
arranged in complete randomized design. The following parameters, leaf length, breadth and leaf number, N and protein
were determined. Results showed that leaf length, breadth and leaf number were significantly higher (p<0.05) recorded in
the control pots. The least % N and protein were recorded in the pots with highest crude oil concentration (50.0 ml). The
results also showed that increasing crude oil concentration, posed higher risk of edibility of the test-plant and no
detectable amount of petroleum hydrocarbon was found in the soils at the end of the experiment. The study concluded
that although cowpea germinated and grew well in crude oil-contaminated soils, its nutrient content was impaired and
edibility not guaranteed.

Air and heavy metal pollution around a steel foundry in Ogijo, Ogun State, Nigeria

Olayinka*, O. O. — 2021-07-15

Effects of crude oil contaminated-soil on the germination and growth of cowpea Vigna unguiculata (L.) Walp

Enajeria G. — 2021-07-15

Structural equation modelling of academic performance in statistics degree programme: A case study of University of Ibadan

Olubusoye O. E. — 2021-07-15

Computational studies of the corrosion inhibition potentials of some derivatives of 1H-Imidazo [4, 5-F] [1, 10] phenanthroline

Obi-Egbedi, N. O. — 2021-07-15

Computational simulations of the corrosion inhibition potentials of four imidazophenanthroline derivatives were carried
out using Density Functional Theory (DFT) with B3LYP/6-31G* method. It was shown that the predictive corrosion
inhibition potentials increase in the order 2-methyl-1H-imidazo[4,5-f][1,10]phenanthroline (MIP) < 3-(1H-imidazo [4, 5-f][1,
10] phenanthrolin-2-yl) phenol (IPP) <2-(2-methoxyphenyl)-1H-imidazo [4, 5-f] [1, 10] phenanthroline (MPIP) < 4-methoxy-
2-(3H-phenanthro [9, 10-d] imidazol-2-yl) phenol (MPP). The anticorrosion potentials were predicted using the quantum
chemical parameters like energy gap (?E), energy of highest occupied molecular orbital (EHOMO), energy of lowest unoccupied
molecular orbital (ELUMO), ionization potential (I), electron affinity (A), polarizability (?), global hardness (?), global softness
(), electronegativity (x) and polar surface area (PSA). Corrosion inhibition potentials increase with increasing EHOMO,
polarizability, global softness and polar surface area (PSA), and decreasing energy gap (?E), ELUMO and global hardness.
Also, the sites of likely electrophilic attack were located on nitrogen and oxygen atoms as shown by high negative
Mulliken charges of these atoms. This implied that the metal surface atoms could be bonded to these inhibitors through
nitrogen and oxygen atoms. From the results, 4-methoxy-2-(3H-phenanthro [9, 10-d] imidazol-2-yl) phenol (MPP) showed
the highest EHOMO, polarizability, PSA, and the lowest ?E, ELUMO, hence the greatest potential of inhibiting corrosion of
metals in aqueous solutions.

Subsistence of four bacteria isolated from Nigerian aquaculture farms on oxytetracyclineor

Adelowo O. O. — 2021-07-15

Isolation and identification of thermophilic cellulolytic yeast from cassava waste dump

Onilude A. A. — 2021-07-15

Cellulase is an enzyme complex which breaks down cellulose to glucose. The need for economical, complete and fast
industrial processes necessitates the use of very active starters able to operate at high temperature of production to
degrade cheap nutrients most of which are cellulolytic; hence the search for thermophilic cellulolytic yeasts from the
environment. Isolation and identification of thermophilic yeasts were made from the soil samples using standard procedures
and obtained isolates were screened for cellulolytic enzymes production. The enzymes were characterised using different
parameters such as temperature, pH, substrate concentrations, enzyme concentrations and metal ion concentrations. A
total of seven thermophilic yeasts were isolated from cassava waste dump sites and identified as Torulopis sphaerica,
Kloeckera apiculata, Pichia canadensis, Pichia species, Candida krusei, Candida utilis and Rodotorula rubra. They
all had optimum growth at temperature and pH of 55ºC and 6.0 respectively. The optimum temperature and pH for
cellulolytic activities ranged from 45-55ºC and 5-6 respectively. Cellulolytic activities increased with increase in the
concentration of substrate, enzymes and metal ions.