Ife Journal of Science

Response surface optimization of lipase production by Pseudomonas sp. on a low-cost shea-nut cake using solid state fermentation

M.O. Kazeem — 2024-04-25

Shea nut cake (SNC) is the solid residue produced after the shea butter extraction process. The SNC could provide a low-cost substrate for bacterial lipase production. Greater yield are among the benefits Solid State Fermentation (SSF). However, there have been less instances of lipase production by bacteria than fungi in SSF. The current study aimed at improving bacterial lipase production on SNC in SSF using Response Surface Methodology. Lipase-producing bacteria (LPB) were isolated from the shea butter mill effluent pond and screened for lipase production on a tributyrin agar plate. The influence of four independent parameters (temperature, pH, moisture content and biosurfactant) on lipase production was studied using Box Behnken Design (BBD) of RSM. Results showed that isolate AO (Pseudomonas sp.) displayed the highest zone of hydrolysis 2 (53 mm). A quadratic regression with R = 0.931 showed that the model is best fitting, and predicted the optimum conditions of significant (P>0.05) growth parameters, including temperature at 40°C, moisture content at 50%, and biosurfactant at 2 mL, which produced 408.25 U/g of experimental lipase. The findings indicate that the model was useful for predicting optimal growth conditions for incresing lipase production in SSF and the low-cost agro- industrial SNC could be a promising substrate for industrial applications.

Histopathological investigation of some facial cosmetic products mixture exposed to fingerlings of mud catfish (Clarias gariepinus)

F.I. Osuala — 2024-04-25

Cosmetics are one of the major pollutants in the aquatic ecosystem due to the quantum of production to meet the astronomical demand of users that eventually becomes harmful to organisms. Changes in physic-chemical parameters such as potential of hydrogen (pH), Electrical conductivity (EC), Temperature (T ^oC) Dissolved oxygen (DO) were investigated at the beginning and after 96 hours of cosmetic exposure. This study also investigated the effects of four facial cosmetic products (Powder, foundation, concealer, and primer) histopathologically in fingerlings of Clarias gariepinus (gills) exposed to binary, trinary, and quaternary mixtures in o laboratory bioassays for 48 hours and 96 hours. The results of pH, T C, EC and DO ranged from 6.21 - 6.64, o 25.40 - 26.70 ^oC, 0.04 - 0.14 mS/cm, and 10.00 -12.00 mg/l respectively. The joint action toxicity evaluation of the binary, trinary, and quaternary mixtures of the cosmetics prepared based on an equitoxic ratio against the test organism was in concordance with the model of synergism. Results showed the prevalence of severe lamellar necrosis in the gills of C. gariepinus which was observed across all combinations except in the combinations of Powder + Primer as well as Powder + Foundation + Concealer + Primer. Moderate lamellar necrosis and hypertrophied epithelium were observed in fish exposed to a mixture of Powder + Foundation + Concealer. The results obtained in this study suggested that the presence of facial cosmetics in the aquatic ecosystem could be dangerous to fish and subsequently human health via biomagnification. Therefore, there is an urgent need for environmental regulators to enforce safety standards for the emission of these selected cosmetics wastes into the waterways to prevent damage to aquatic organisms and public health issues.

Kinetics of antibacterial activities of cellulose nanocrystals and their silver-zinc oxide nanocomposites: Application as potential disinfectants

F.O. Agunbiade — 2024-04-25

Cellulose nanocrystals (CNCs) were produced from corncob and used as reducing agent in the formation of ZnO/CNCs, Ag/CNCs, and ZnO-Ag/CNCs composites and applied as antibacterial agents for both grampositive and gram-negative bacteria and the kinetics of microbial growth inhibition studied. The CNCs and composites were characterized by UV-visible and Fourier transform-infrared (FTIR) spectroscopy. The characterization results revealed that the functional groups of CNCs were affected by their interactions with Ag⁺ and Zn²⁺ ions. The composites at 100 mg/mL displayed activities against Gram-positive bacteria - Bacillus subtilis, Staphylococcus aureus, Staphylococcus epidermis, Bacillus coagulans and Enterococcus faecalis and Gram-negative bacteria - Escherichia coli, Klebsiella pneumonia, Salmonella typhimurium, Pseudomonas aeruginosa, Enterococcus faecium and Acinetobacter baumanii) bacteria with inhibitory zones ranged between 9-46 mm. The kinetics of inhibition showed that the composites treated water had 4 to 28 times lower rate constants compared to the untreated water. This implied that the composites inhibit growth rates and have the potential of disinfecting for between 4 to 28 h depending on the bacteria. The materials showed better growth inhibition rate on gram-positive bacteria than on gram-negative. These composites may have potential applications as disinfectants in personal care products and serve as more eco-friendly alternative disinfectants to chlorophenols.

Preparation of styrene-based imprinted polymer for the adsorption of hazardous bromocresol green dye: Equilibrium, kinetics and thermodynamics study

K.N. Awokoya — 2024-04-25

In this study, styrene was used as a functional monomer for the production of molecularly imprinted polymer (MIP) via free radical polymerization method, using bromocresol green dye (BCG) as template. A non-imprinted polymer (NIP), that excluded the template, was also synthesized. Both polymers were applied for the removal of BCG from aqueous medium. The synthesized polymers were characterized with Fourier transform infrared spectroscopy, scanning electron microscopy, and X-ray powder diffraction spectroscopic techniques. The effect of operating variables, such as pH, contact time, initial dye concentration and process temperature, on the efficiencies of the polymers in removing the dye were evaluated. Equilibrium time of BCG adsorption onto the MIP was reached within 40 min, with adsorption capacity of 49.68 mg g^-1 . The adsorption process followed the pseudo-second-order kinetic and Freundlich isotherm models, while chemisorption mechanism was predicted. The adsorption process was spontaneous and exothermic in nature, with DH values of -140.03 and -25.01 kJ/mol^-1 recorded for BCG removal by MIP and NIP, respectively. The styrene-based MIP showed good mechanical stability, and retained up to about 99% of its adsorption capacity after six sequential cycles of regeneration. Comparatively, the MIP (99.81mg g^-1 ) performed considerably better than its NIP (59.00 mg g^-1 ) analogue in the removal of BCG from aqueous medium, thus affirming the potentials of the molecular imprinting technique in the production of efficient adsorbents for adsorption of toxic dyes from industrial effluents.

Physical quality and antibiotic susceptibility profile of Escherichia coli isolates from roof-harvested rainwater: A microcosm study

M.A. Titilawo — 2024-04-25

Owing to the inadequate supply of potable water in rural settlements in developing countries, roof-harvested rainwater (RHRW) has been favoured as an alternative source of water supply. The present study investigated the physical characteristics and microbial quality of 10 RHRW samples collected from storage tanks in Ikwo community of Ebonyi State, Nigeria. Triplicate water sampling was performed over a 3-month sampling regime. Onsite determination of odour, colour, pH and temperature, and isolation and enumeration of Escherichia coli were done using standard procedures. The identity of the isolates was confirmed using molecular techniques, and the susceptibility of the isolates to 11 antibiotics was determined following the Kirby-Bauer disc diffusion assay. Multiple antibiotic resistance phenotypes and indices (MARPs and MARI) were equally determined. Our findings revealed that the RHRWs had unobjectionable odour and were colourless. Across the 3-month o sampling, the pH ranged from 6.9 to 7.8 while the temperature was between 24 °C and 29 C. While E. coli was absent in samples E (September), H (August and October) and J (August, September, and October), the highest E. coli count in August, September, and October was 37, 32, and 38 cfu/100 mL, respectively. The antibiotic susceptibility test on 40 E. coli isolates showed high resistance to ampicillin (100%), aztreonam (98%), cefotetan (97%), nitrofurantoin (90%), imipenem (83%), streptomycin (72%), and ertapenem (69%). Interestingly, the ighest MARP, 11 (AK/S/ETP/IMI/OFX/NOR/AMP/CTT/ATM/F/TE) (sample B), and the least, 4 (IMI/AMP/CTT/ATM) were recorded in samples B and D, respectively in September. MARI was from 0.42 to 1.00. The physical parameters conform with WHO standards, on the other hand, detection of E. coli poses risks of water-borne illness(es) and transmission of antimicrobial resistance. Hence stringent measures including proper treatment, sanitation and hygiene are advocated to safeguard the health of dwellers who depend on this water source for daily life activities.

Ethnobotanical study of twenty species in the family Asteraceae in Ile-Ife, Osun State, Nigeria

E.T. Odelade — 2024-04-25

Ethnobotanical study was conducted on 20 plants belonging to 18 genera of the Asteraceae family. The aims of this research were to explore the current ethnobotanical status of the identified plant species, document their indigenous utilization for diverse purposes within the specific research area and assess the extent of Asteraceae plant usage by the local population. Data were collected through semi-structured questionnaires and open-ended interview techniques with different categories of informants in the Ife Central Local Government Area of IleIfe, Osun State, Nigeria. Demographic data of respondents were analyzed using a descriptive statistical method, providing understandings into their characteristics. The ethnobotanical survey results were subjected to quantitative analysis employing several parameters. The Relative Frequency of Citation (RFC) was utilized to determine the prominence of plant species in terms of citations. The Use Value (UV), Fidelity Level (FL), and Informant Consensus Factor (ICF) were employed to assess plant importance, therapeutic efficacy, and consensus among informants, respectively. Ethnobotanical study of the selected Asteraceae plants revealed the traditional uses of these plants for diverse purposes for both humans and livestock. The average ICF value was 0.92, indicating a relatively high consensus among the respondents. Ageratum conyzoides, Tithonia diversifolia, Aspilia africana, Launaea taraxacifolia and Tridax procumbens were the most cited of all the species, hence their high RFC values. Fidelity Level (FL) had the highest value in Aspilia africana, Tithonia diversifolia and Ageratum conyzoides while Acmella radicans had the lowest FL value. According to this study, Ageratum conyzoides (0.10) and Launaea taraxacifolia (0.10) had the highest use value. The study concluded that the Asteraceae species have several edible, ornamental and medicinal uses, which have not been explored extensively in the study area.

Effects of sprouting on the antioxidant potentials of garlic (Allium sativum L.) And onions (Allium cepa L.)

J.O. Ebhomienlen — 2024-04-25

No Abstract

Microfacies and mineralogical analyses of the late cretaceous carbonate rocks from The Central Benue Trough, Nigeria

G.O. Aigbadon — 2024-04-25

The Cretaceous limestone facies from Yandev section in the central Benue Trough, Nigeria constitutes parts of the potential reservoirs and sources rocks for petroleum prospects in the basin. The central Benue Trough is the least studied basin among its contemporaries due to lack of subsurface data. Detailed mineralogical, facies analysis and diagenesis of these carbonate rocks in the basin have not received significant study. The aim of this study was to employed multifaceted methodology such as sedimentological, facies analysis petrographic and geochemical approaches which was lacking in previous research in the trough. The sedimentological analysis was done to evaluate fabrics grain sizes, and lithology types. For petrographic analysis, thin sections were prepared and examined under a petrographic microscope and categorized according to Dunham's classification. Geochemical analysis involved X-ray fluorescence (XRF), X-ray diffraction (XRD), and scanning electron microscope - energy dispersive X-ray spectroscopy (SEM-EDX) techniques to unveil mineralogical, oxide, and elemental compositions. The sedimentological results revealed light to dark grey medium to fine-grained limestone facies with intercalation of dark grey shales and siltstones. The XRD mineralogy data, revealed calcite (60.00 - 64.10%), quartz (14.30 - 51.00%), albite (12.30 - 19.00%), and chlorite (6.30 - 8.10%). Microfacies results revealed distinct sandy bioclastic wackstone and sparitic intraclastic packstone, as well as micritic intraclastic wackestone and sparitic bioclastic packstone. SEM images highlighted the intricate composition, including elongated structures, whites and dark spots suggesting varying conditions of deposition. Elemental analysis through EDX emphasized significant proportions of carbon, oxygen, sodium, potassium, calcium, silicon, aluminum, iron, and magnesium. Based on sedimentological, biofacies, lithofacies and geochemical evidence we infer that the carbonate sediments were mainly deposited in a shallow marine depositional environment (inner to outer neritic).

Structural characterization and evaluation of mycogenic zinc oxide nanoparticles from the cell-free culture-extract of Aspergillus niger

A.K. Ajijolakewu — 2024-04-25

Advances in the biological synthesis of nanoparticles have attracted decisive research attention in recent years. This is due to their eco- friendliness, nontoxicity and large spectra of applications. In this work, the structural characteristics and the purity of biogenic zinc oxide (ZnO) nanoparticles were assessed. Zinc oxide (ZnO) nanoparticles were synthesized extracellularly using the culture filtrate of Aspergillus niger, in the presence of zinc acetate dihydrate, as a precursor. The structural characteristics and purity of the nanoparticles were examined using standard characterization methods viz UV-visible spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier-transmission infrared (FT-IR) spectroscopy and X-ray diffraction (XRD). Results revealed a peak at 311nm and whitish and spherical particles with particulate sizes between 30 and 40 nm for the UV- -1 visible spectroscopy and SEM respectively. On the FT-IR scale, absorption peaked at 548 cm in the spectra region known for the functional groups of ZnO nanoparticles; while the average crystalline size was 21 nm based on XRD analysis. Findings in this study revealed that the ecofriendly biogenic nanoparticles synthesized by common fungi, such as Aspergillus niger, possess desirable qualities comparable to those from non-ecofriendly and costly chemical processes, which are currently employed for an array of applications.

Lithological discrimination and mapping in part of the upper Benue Trough using Landsat 8

O.A. Abodunrin — 2024-04-25

This study focused on evaluating the efficiency and complementarity of image enhancement techniques for lithological discrimination and mapping in the upper parts of Benue Trough using Landsat 8 data. To achieve this, image enhancement techniques such optimum index factor, band ratio, principal component analysis, and minimum noise fraction were applied on Landsat 8 OLI data covering parts of the Upper Benue Trough. False colour composites (FCC) were created from three most informative derivatives of these image enhancements. The FCCs were compared in terms of their capability to differentiate different lithological units in the study area by comparing the FCCs with existing geological map. The results show that the FCC created from band ratios provided the highest amount of information, while those created based on optimum index factor provided the least amount of information with respect to lithological discrimination. Additionally, it was observed that the FCCs created from the derivatives of band ratio, principal component analysis and minimum noise fraction provide complementarity. Thus, the three FCCs from these three enhancement methods were fused into a single image, which further aided lithological discrimination. By combining the outputs from three image enhancement techniques, most of the sedimentary and crystalline rocks in the study area were successfully delineated. The method adopted in this study particularly the fusion of outputs from band ratio, principal component analysis and minimum noise fraction represents a novel approach that is suitable for lithological mapping in remote areas, particularly arid and semi-arid terrains with considerable rock exposure.

Investigating Landsat data for continuous monitoring of ground electrical conductivity: implication for propagation at medium frequency in Ondo West

R.A. Adenodi — 2024-04-25

Ground electrical conductivity (GEC) has many applications, which makes it worthy of continuous research. Apart from the configurations of the radio transmitter and receiver, it is a major determinant of the electric field intensity of radio waves in the Medium Frequency (MF) band. It is usually measured in such a way that both the researcher and the measuring instrument are in direct contact with the ground, and measurements are made at some predetermined constant intervals to ensure good spatial coverage and even spatial distribution. The direct method becomes cumbersome when the field of study is large because the GEC over the licensed coverage area must be known such that electric field intensity can be predicted. At the planning stage, this ensures all parts of the licensed region are reached by useful signals that can suppress interference at all times and seasons. The study is motivated by the possibility of using Landsat to estimate GEC. This study utilizes Landsat images to first estimate the normalized difference salinity index and then, with the aid of map algebra, generate another raster 2 whose pixels' values are the GEC. The study covers a landmass of 967 km in the Ondo West Local Government Area (OWLGA). During analysis, the GEC was divided into five classes. The results reveal that the ranges of very low, low, moderate, high, and very high GEC are 0.124 to 0.437, 0.438 to 0.937, 0.938 to 1.635, 1.636 to 2.524, and 2.525 to 3.600 mS/m, which have mean values of 0.346 ± 0.109, 0.754 ± 0.103, 1.071 ± 0.089, 1.351 ± 2 0.067, and 1.564 ± 0.106 mS/m, and are dispersed over 176.45, 202.24, 214.14, 374.17, and 228.56 km , respectively. The values of GEC, their respective coverage, and spatial distribution recorded in this study are strong enough to sustain the propagation of useful electric field intensity over the entire landmass of Ondo West Local Government if a medium wave is established. The study recommends that the change in GEC with time in this field be studied.

A time series analysis of monthly issuance of plant import permits in Nigeria

O.E. Majebi — 2024-04-25

An import permit is issued by the National Plant Protection Organization of each country, known in Nigeria as the Nigeria Agricultural Quarantine Service (NAQS), to allow the importation of pest-free plants and prevent the introduction of quarantine pests or check the entry of regulated non-quarantine pests of imported plant commodities. Issuance of import permits at the Post-Entry Quarantine, Surveillance and Diagnostic Station (PEQDS), Ibadan is mostly for germplasm materials mainly used for cultivation, which poses a high risk of pest introduction. Thus, this study investigated the statistical components of the issuance of import permits at the PEQDS using the Time Series approach to determine the peak period of collection essential for planning phytosanitary activities to mitigate the introduction of foreign pests. The dataset of the monthly issuance of import permits from January 2012 to July 2022 was analysed. From the preliminary study, we observed that the series exhibit seasonal and stationary components with no definite trend pattern, hence we modelled the series using a Seasonal Autoregressive Moving Average (SARIMA) model. Several models were estimated and the best model (SAR(12)) for forecasting the future import permit collectionwas selected based on the forecast accuracy measures. The forecasted values indicated the highest issuance of import permits in May and September, each year and showed a fluctuating movement over time in the future. To further prevent pest incursion and facilitate trade, NAQS needs to operate round-the-clock surveillance, keep its staff on high alert and adequate facilities operational for more effective activities. Other factors responsible for low and fluctuating issuance of import permits should also be investigated.

in vitro β-hematin inhibitory activity and antioxidant properties of four selected medicinal plants used in the management of malaria in southwestern Nigeria

G.O. Omotosho — 2024-04-25

No Abstract

Production of vinegar from waste fruits using Acetobacter species

S.K Paul — 2024-04-25

Vinegar is an organic substance that contains about 5% acetic acid and is made from the oxidative fermentation of alcohol by acetic acid bacteria. The aim of this study was to produce vinegar from the juices of waste fruits. Proximate and physicochemical analysis was carried out on the juices of orange, sugarcane, tomato, and pineapple using standard techniques. Twenty-one (21) species of acetic acid bacteria were isolated and identified using glucose-yeast-Calciumcarbonate (GYC) agar. The juices were fermented for 7 days using Saccharomyces cerevisiae, and subsequently, for 28 days, four alcohol-tolerant Acetobacterspecies were selected and inoculated into the fermenting media. The produced vinegar was sensory evaluated, following a nine-point hedonic scale. The antibacterial and antifungal effects of the vinegar were tested on fresh cabbage at various contact times (0, 5, and 10 min) and concentrations (5, 10, and 15 % v/v). The physicochemical parameters analyzed in fermentation using S. cerevisiae showed a decrease in pH, specific gravity, and brix, while the percentage of alcohol content increased. As the fermentation using Acetobacter species progressed, pH further decreased, titratable acidity increased in a range of 6.6-7.7%, and specific gravity also decreased while specific gravity increased in Acetic acid fermentation. Sensory evaluation showed a score range of 5.7–6.8 for pungency, 6.8–7.4 for appearance, 6.4–7.9 for aroma, 5.8–7.4 for taste, and 6.9–7.9 for acceptability. The best results for bacterial and fungal loads 5 on cabbage were at a concentration of 15% at 10 min. Drastic reduction of bacterial load was from 2.07×10 to 4 4 3 2.7×10 CFU/g, while fungal load reduced from 4.9×10 to 6.7× 10 CFU/g. To evaluate significance, an ANOVA was performed (p<0.05) and Duncan's test was used for multiple comparisons. Vinegar was successfully tested to be effective as an antimicrobial agent. Future research should look into process optimization, strain improvement, and the adoption of agro-allied wastes for biotechnology.

Advancing supercapacitor performance: a comprehensive review of electrochemical conversion of coconut shells into activated carbon nanofibers

I.I. Ajibade — 2024-04-25

This assessment provides a comprehensive evaluation of the limitations associated with the application of supercapacitors, along with the imperative to enhance their functionality. Following this, the advantages of Electrochemical Double Layer Capacitors (EDLC) are discussed in comparison to other types utilized in supercapacitor contexts. The transformation of coconut shells into carbon nanofibers is extensively investigated through various methodologies, highlighting both their benefits and limitations. It becomes evident that the current utilization of coconut shells has not yet achieved optimal sustainability or viability for energy storage purposes. Nevertheless, coconut shells offer a widely available and sustainable resource that can be converted into Activated Carbon nanofibers for energy storage applications. Diverse techniques have been employed to produce these ACB nanofibers, each targeting specific objectives including improved energy density, adaptable diameter, reduced energy consumption, and faster charging times. Despite these accomplishments, it is evident that numerous significant properties of carbon nanofibers derived from coconut shells remain unexplored, leading to substantial knowledge gaps that must be addressed for each technique. Therefore, further research is warranted to advance the comprehension of key parameters associated with various methods, ultimately facilitating the development of highly desirable carbon nanofibers sourced from coconut shells and catering to the requirements of sustainable energy storage applications.