Journal of Biological and Allied Sciences
The journal is an official publication of the Faculty of Life Sciences, University of Ilorin and publishes original research and review articles in the fields of Biological and Allied Sciences. It is an open access, peer-reviewed journal and online. The aim is to provide an international forum to inform the academic and research world of new ideas, innovations and developments in the fields. The journal publishes original articles in all areas of Biological and Allied Sciences. These include Agricultural Science, Anatomy, Biochemistry, Bioengineering/Biomedical Engineering Bioinformatics, Biophysics, Biotechnology, Biostatistics/Biometry, Cell Biology and Genetics, Ecology, Environmental Science, Epidemiology and Public Health, Immunology, Marine Biology/Oceanography, Microbiology, Molecular Biology, Neuroscience, Nursing, Optometry and Vision Sciences, Palentology, Pharmacology, Pharmaceutical Sciences, Physiology, Phytomedicine, Plant Biology/Botany, Taxonomy and Systematics, Toxicology, Veterinary Medicine and Zoology/Animal Biology
Impact of crude oil-polluted soil on germination and development of Abelmoschus caillei (A. Chev.) Stevels seedlings
Crude oil pollution poses a major problem in many countries of the world, especially in oil-rich nations where it negatively impacts agricultural production. Abelmoschus caillei (A. Chev.) Stevels (West African okra), a vital vegetable prized for its high fibre and mineral contents, is widely cultivated in oil-producing regions of Nigeria, yet its response to crude oil-contaminated soil remains poorly understood. The present study examines the effects of crude oil-polluted soil on the germination and seedling development in West African okra, Abelmoschus caillei (A. Chev.) Stevels. Five crude oil-contaminated soil treatments denoted as T1, T2, T3, T4 and T5 (with 0.1%, 0.5%, 1.0%, 2.5% and 5% v/w crude oil to dried sandy-loam soil) and uncontaminated (control) soil were set up, with each replicated three times. Ten viable seeds of A. caillei were planted into the treatment pots in a screen house and observed for germination, growth, chlorophyll content, and biomass of the seedlings. The results showed that seedling emergences started at 6 days after sowing in the crude oil treatments and the control, but the % germination decreased in T2 to T5 (with <0.5% crude oil) by 3.3-13.7%. Plant height was markedly reduced under high contamination, with T5 having the least at 2 WAS (4.00 cm) and 4 WAS (6.76 cm) compared with the control (12.08 cm). Leaf production declined from 3.42 in T1 to 2.16 in T5. Chlorophyll a decreased significantly in T5 (6.85 mg g⁻¹) from T1 (10.87 mg g⁻¹). Fresh weight was significantly highest in T1 (7.39 g) and lowest in T5 (3.01 g). Overall, crude oil contamination adversely affected the germination, growth and pigment development of A. caillei, although mild contamination elicited a transient stimulatory response.
Prevalence of myopia among teenagers attending University of Ilorin Secondary School, Ilorin, Kwara State, Nigeria
Myopia is a significant and growing public health concern, with its prevalence increasing disproportionately among younger age groups. This study aimed to determine the prevalence of myopia among teenagers attending the University of Ilorin Secondary School, Ilorin, Kwara State, Nigeria. A cross-sectional, school-based study was conducted among 218 teenagers aged 13 to 17 years (mean age: 14.59 ± 0.9 years). Ocular examinations included visual acuity assessment, ophthalmoscopy, and objective refraction by retinoscopy. Myopia was defined as a spherical equivalent refraction (SER) of ≥ −0.50 DS and was further classified as low (< −3.00 D), moderate (−3.00 D to −6.00 D), or high (> −6.00 D). Data were analysed using IBM-SPSS version 23.0. Results were expressed as frequencies and percentages, and the Chi-square test was used to assess associations at a significance level of p < 0.05. The overall prevalence of myopia was 18.81% (n = 41). Females exhibited a significantly higher prevalence of myopia (68.29%) compared to males (31.71%), and this difference was statistically significant (χ² = 4.343, p = 0.037). Low-degree myopia was the most common form, accounting for 95.12% of myopic participants. The prevalence of myopia was highest among 14 years old participants (27.91%). Approximately one in five teenagers in this study population had myopia, with females being the most affected. These findings underscore the need for large scale, population-based surveys to establish the full magnitude of myopia among Nigerian adolescents and to guide targeted public health interventions.
Impact of zinc oxide nanoparticles on the bio-productivity, seed quality and biochemical properties of Arachis hypogaea (L.)
Zinc oxide nanoparticles (ZnO-NPs) offer improved nutrient delivery, although their optimum concentrations and impact on groundnut crops remain unclear. This study investigated the impact of zinc oxide nanoparticle (ZnO-NPs) concentrations on the growth performance, yield, and biochemical properties of Arachis hypogaea L. (groundnut). The concentrations of ZnO-NP investigated were 0.00 (control), 0.25, 0.50, 0.75, 1.00 and 1.25 g/L. The ZnO-NPs synthesized by the direct precipitation method had FTIR that peaks at 455.22 cm-1 and 1384.94 cm-1, corresponding to Zn-O stretching and deformation vibration. The rod-flower shape of ZnO-NP had a particle size of < 0.99 with good purity. The synthesized ZnO-NPs significantly increased (p<0.05) percentage seed germination that ranged from 66.67% at 0.25 g/l to 97.67 at 1.25 g/L when compared with the control (56.65%). All ZnO-NP treatments enhanced morphological growth characters and yield attributes when compared with the control. However, chlorophyll content under ZnO-NPs were at par with the control. Nitrate reductase and carbonic anhydrase enzymes increased with the increase in the concentrations of nanoparticles. Seed quality in terms of mineral and proximate compositions showed inconsistent trends. However, Zn and other mineral elements such as K Mg, P and Na were significantly higher under ZnO-NPs when compared with the control. Similarly, ZnO-NPs limit fat accumulation in seeds but showed marked influence on ash, fibre, protein, carbohydrate and energy values. It can be concluded that groundnut bio-productivity, biochemical attributes and seed quality were generally enhanced by zinc oxide nanoparticles with doses between 0.75 and 1.25 g/L showing the most profound effects.
Molecular identification and phylogenetic analysis of Corchorus olitorius using psbA-trnH plastid DNA region
Corchorus olitorius L. (commonly known as jute mallow) is a widely utilised leafy vegetable valued for its nutritional and medicinal benefits. It exhibits considerable genetic diversity, making it an important crop for breeding programmes and conservation efforts. However, to achieve this, accurate identification is required. Morphological methods of identification are found to be insufficient as it often fails to reveal the intra-specific differences and evolutionary relationships existing between closely related taxa. In contrast, Molecular methods of identification such as DNA barcoding are accurate and reliable for species identification and elucidating evolutionary relationship existing between closely related taxa. This study aimed to utilize DNA barcoding as a molecular technique to identify C. olitorius using the psbA-trnH plastid DNA region. DNA was extracted from leaf tissues, amplified and sequenced. BLAST analysis was conducted on the NCBI Genbank database, followed by multiple sequence alignments. Maximum Likelihood method was employed to infer phylogeny using MEGA11 software. Results revealed the psbA-trnH region produced a DNA barcode of 359 bp sequence. Also, BLAST similarities ranged from 90% to 100% across 21 Genebank accessions. Phylogenetic analysis revealed a strong evolutionary relationship between C. olitorius, C. orinocensis, and C. cunninghamii supported by high bootstrap values. This research provides DNA barcodes for molecular identification of C. olitorius as well as information about its evolutionary relationships with closely related taxa. Such information will aid plant breeding, conservation, and biosystematics endeavours.
Antibacterial activity of extracts of Vitex doniana (black plum) stem bark
Bacteria are a leading cause of diarrhoea in humans and the use of orthodox drugs in its treatment has been found to possess certain side effects as well as economic burden. This study aimed at evaluating the antibacterial activity of aqueous, methanol, ethylacetate and n-hexane extracts of Vitex doniana (black plum) stem bark on some diarrhoeal causing organisms. Fresh samples of Vitex doniana stem bark were collected from Kontagora Local Government Area of Niger State, Nigeria. Preparation, extraction, secondary metabolite screening and antibacterial activities of the different extracts of Vitex doniana stem bark were carried out following standard procedures. The results revealed that all the extracts contained different concentrations of flavonoids, alkaloids, tannins and phenols. Aqueous extract contained a significantly (p < 0.05) lower concentration of flavonoids (20.40 ± 0.04 mg/g) when compared to other extracts. However, there was a significantly (p < 0.05) higher concentration of alkaloids in the aqueous extract (40.67mg/g) when compared to alkaloids concentration in the methanol (30.00 mg/g) extract. A significantly (p < 0.05) higher concentration of tannins was recorded in the methanol extract (0.99 mg/g) when compared to tannins concentration in ethylacetate (0.21 mg/g) extract. A significantly (p < 0.05) higher concentration of phenol was recorded in the aqueous extract (352.70 mg/g) as compared to the n-hexane (16.27 mg/g) extract. The result of the zone of inhibition for different extracts revealed that, at higher concentrations of 100% and 75%, the growth of Escherichia coli, Pseudomonas spp, Staphylococcus aureus and Salmonella spp were significantly (p < 0.05) inhibited, suggesting that the inhibitory activities of the extracts are dose-dependent. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the different extracts showed varying results across different extracts. In conclusion, the study demonstrated that both the aqueous and n-hexane extracts of Vitex doniana stem bark possess bacteriostatic effects whereas methanol and ethylacetate extracts exhibited bacteriocidal effects especially at higher concentrations.
Anti-anaemic activity of aqueous extract of Abrus precatorius (L.) leaves in iron-deficient anaemic Wistar rats
Abrus precatorius leaves have been claimed to be used to manage anaemia without any substantive scientific study. Therefore, this study investigated the effect of aqueous extract of A. precatorius leaves (AEAPL) in iron-deficient diet-induced anaemia in Wistar rats. Fifty Wistar rats (50. 07 ± 3.25 g) were completely randomised into three groups, CF (commercial feed; n = 10), ISD (iron sufficient diet; n = 10) and IDD (iron deficient diet, ID; n = 30). After 8 weeks of feeding on their respective diets, the levels of serum iron (SFe), haemoglobin (Hb), packed cell volume (PCV), red blood cell (RBC), and soluble transferrin receptors (sTfR1) were determined. Thereafter, the animals in group CF and ISD were oral gavaged with 0.5 ml of distilled water, each, for 14 days, while the iron deficient rats in group IDD were re-assigned into IDD100, IDD200 and IDD400 and orally administered AEAPL at 100, 200 and 400 mg/kg body weight (BW) for 14 days. The ISD and IDS were subjected to proximate analysis whilst BW, haematological parameters, gastric pH and sTfR1 levels were determined in the animals. The moisture contents, crude lipids, crude protein, crude fibre, nitrogen free extract of the IDD and ISD were not significantly (p > 0.05) different from each other whereas the ash contents of ISD was significantly (p < 0.05) higher IDD. By the first three weeks, the BW of the ISD, IDD and CF exposed animals were not significantly (p > 0.05) different from each other whereas, afterwards, the BW of the IDD-exposed animals had slow growth when compared with ISD and CF. The 8-weeks exposure of the rats to IDD significantly (p < 0.05) reduced SFe, Hb, PCV and RBC by 130.68%, 33.21%, 36.75%, and 59.18% and increased sTfR1 by 43.43% respectively. The 400 mg/kg BW of AEAPL restored (p<0.05) the anaemic-related BW of the animals. Furthermore, the IDD-related 37.18%, 33.98%, 34.01%, 26.94% and 25.77% significant (p < 0.05) reductions in RBC, Hb, PCV, mean corpuscular volume and platelets were significantly (p < 0.05) and dose-dependently increased by the 100, 200 and 400 mg/kg BW of AEAPL. The IDD-treatment related increases (p < 0.05) in sTfR1 and pH of gastric acid compared well (p > 0.05) with those of AEAPL-, ISD- and CF-treated animals. The study concluded that A. precatorius leaf extract exhibited anti-anaemic activity, with the 400 mg/kg BW exhibiting the most pronounced activity.
Effects of kolanut pod-derived biochar on the growth and nutritional quality of Solanum macrocarpon L. grown on cadmium-polluted soil
Cadmium (Cd) contamination of agricultural soils severely limits crop productivity and poses health risks through the food chain. This study evaluated the effect of kolanut pod-derived biochar on the growth and mineral nutrient content of Solanum macrocarpon L. grown in Cd-polluted soil. A screen house experiment was conducted using a Completely Randomized Design with four treatments: Control (no Cd, no biochar), Cd only (27 mg kg⁻¹), Cd + 17 g biochar, and Cd + 50 g biochar, each replicated thrice. Growth parameters (plant height, number of leaves) were recorded weekly for four weeks, and mineral concentrations (Fe, Mg, Zn, Mn, Ca) in leaves and roots were quantified via Atomic Absorption Spectrophotometry after harvest. Results indicated that Cd stress reduced plant height (Control: 8.50 ± 2.18 cm; Cd: 9.63 ± 2.47 cm at week 4 compared to Cadmium + 50 g Biochar) and number of leaves (Control: 8.00 ± 2.00; Cd: 5.33 ± 1.53) relative to control, though differences were not statistically significant (p > 0.05). Biochar addition, particularly at 50 g, enhanced growth, with week 4 mean heights of 10.33 ± 5.27 cm and 8.07 ± 0.61 cm for 50 g and 17 g treatments, respectively. Biochar also influenced nutrient uptake: in roots, Fe content increased significantly with 17 g biochar (160.67 ± 12.85 mg kg⁻¹) compared to Cd only (104.67 ± 0.29 mg kg⁻¹, p ≤ 0.05), while Mg was highest in Cd-only roots (167.00 ± 19.94 mg kg⁻¹). In leaves, Mg peaked with 17 g biochar (165.33 ± 2.68 mg kg⁻¹), and Fe remained highest in the control (129.83 ± 24.56 mg kg⁻¹). Biochar application increased soil pH (7.35), cation exchange capacity (21.42 mEq 100g⁻¹), and organic matter (8.2%), reducing Cd bioavailability. The results showed that kolanut pod biochar at higher rates alleviated Cd toxicity, improve nutrient composition, and enhance physiological performance of S. macrocarpon. This offers a sustainable, low-cost amendment for Cd remediation and food safety improvement.
Molecular identification and chemical profile of parasitic higher plants in the botanical garden of University of Ilorin, Ilorin, Nigeria
Parasitic higher plants cause plant diseases and may also serve as agents that spread plant viruses. This study was carried out to identify parasitic higher plants in the University of Ilorin Botanical Garden and to investigate the phytochemicals they contain. Survey of parasitic higher plants existing in the Unilorin botanical garden was carried out and documented. Their leaf samples were collected and subjected to molecular identification. The obtained sequences were compared with those available in the NCBI database. Only two parasitic higher plants were identified as Cuscuta europaea (on a moringa tree), and Moquiniella rubra (on a citrus tree). For the phytochemical analysis, the dried leaves were extracted using 70% ethanol and screened using GC – MS. A total of one hundred and three bioactive compounds were identified, with fifty four found in Cuscuta europaea and forty nine present in Moquiniella rubra. Twenty five phytocompounds out of the 103 identifie3 were common in both parasitic higher plants. However, only seven compounds in each species appeared in significant amounts. Some of the major compounds detected, such as phytol, squalene, and hexadecanoic acid, are known to possess antimicrobial, antioxidant and anti-inflammatory activities. The findings suggest that although these parasitic plants pose a biological threat to their hosts, they also have the potential to serve as valuable sources of natural therapeutic products.
Gas chromatographic-mass spectrometry-based chemotaxonomic profiling of Senna, Cassia, and Albizia species of the Fabaceae family
Senna, Cassia and Albizia are diverse genera within the Fabaceae family, characterised by complex taxonomy of morphological plasticity and hybridisation. This study employed Gas Chromatography-Mass Spectrometry (GC-MS) to profile the diethyl ether leaf extracts of nine species: Senna alata, C. fistula, S. podocarpa, S. obtusifolia, S. occidentalis, S. siamea, Albizia lebbeck, A. adianthifolia, and A. zygia. A total of 117 phytocompounds were identified across all the species studied, with 28 to 40 identified per species. Alcohols (34.19%) and carboxylic acids (17.95%) were the most prominent compounds. Four compounds: -3,7,11,15-Tetramethyl-2-hexadecen-1-ol, Phytol, 9-Octadecenamide, and n-Hexadecanoic acid- were present in all the species. Similarity indices ranged from 19.61% (S. siamea and S. podocarpa) to 58.62% (S. alata and S. occidentalis). Multivariate analyses revealed distinct groupings, notably the divergence of Albizia lebbeck, which formed a separate cluster characterized by a high abundance of 1-Monolinoleoylglycerol trimethylsilyl ether, Benzeneacetic acid, and 6,10-Dodecadien-3-ol, among other compounds. Conversely, S. podocarpa showed close affinity with Albizia species, defined by their shared abundance of alcohols (n-Nonadecanol-1 and 2-Pentadecyn-1-ol) and sterols (Lupeol and β-Sitosterol). These chemotaxonomic findings complement existing morphological data and provide refined differentiation among closely related species. The study demonstrates the value of GC-MS phytochemical profiling in resolving systematic relationships within Fabaceae.
Escherichia coli endotoxin modulates haemolymph-mediated immune system of Achatina fulica (Bowdich 1822)
Achatina fulica (Bowdich,1822), is a unique species due to its ability to maintain three different life cycle stages, demonstrating exceptional capability to survive in its environment, despite microbial challenges, for millions of years. The survival of the snail is important for the ecology and should be studied. There is however a dearth of empirical information about the effects of endotoxin on the immune system of Achatina fulica in particular and to what extent the endotoxin can induce the production of immune-related molecules, of diverse significance (when explored) from A. fulica. This research was aimed at investigating the phenoloxidase activity and Escherrichia coli endotoxin-induced hemolymph coagulation in the A. fulica. Fractions of haemolymph from twelve A. fulica snails were exposed to endotoxin while the control was made endotoxin–free (0.002EU/ml). Haemolymph:plasma (2:3v/v) was exposed to different concentrations of endotoxin. The concentration of coagulated protein and activity of phenoloxidase were then determined. In the results, significantly higher endotoxin-induced protein coagulation was observed in the haemolymph fractions (p < 0.05). Maximum protein coagulation in the mixture of HL/plasma 2:3 was recorded. Exposure of the HL/plasma at optimal ratio to varied endotoxin caused linear protein coagulation up to 2.5EU/ml, beyond which it remained unresponsive to further increase in endotoxin doses. The plasma exhibited the highest phenoloxidase activity up till 10 EU/ml. There was endotoxin-induced protein coagulation and phenoloxidase activity which were endotoxin-concentration-dependent. This study has therefore highlighted the roles of coagulation and phenoloxidase reactions in A. fulica immunity and the potential of A. fulica hemolymph as a model for innate immune studies and bioassay development.
Cytotoxic effects of aqueous extract of Ocimum gratissimum using Allium cepa assay
The Allium cepa assay serves as a significant in vivo model for evaluating the cytotoxic and genotoxic potential of various substances. The increasing use of herbal remedies has raised concerns over their potential cytogenotoxic effects. This study evaluated the cytotoxic impacts of aqueous leaf extract of Ocimum gratissimum using the Allium cepa assay. Onion bulbs were exposed to different concentrations (0%, 20%, 40%, 60%, 80%, and 100%) of the extract for 10 days. The 0% treatment (containing distilled water) serves as the control. Chromosome spreads were prepared using standard protocols. Root length, mitotic index (MI), and chromosomal aberrations (CAs) were assessed. Results showed a concentration-dependent reduction in root growth and mitotic activity. The mitotic index significantly decreased with increasing extract concentration, while chromosomal abnormalities, including stickiness, bridges, and laggards, were observed. Although lower concentrations (20-40%) had less effect on the cells, the treatments still showed a significant cytotoxic effect (p < 0.05) compared to the control. The higher the concentration, the greater the clastogenic changes. This study demonstrated that O. gratissimum has potential cytotoxic and genotoxic effects at high concentrations, warranting its cautious use in traditional medicine.
Molecular identification and biosurfactant production by Pseudomonas spp and Alcaligenes spp from selected automobile workshops in Ilorin, Nigeria
This study investigated production of biosurfactants (surface-active agents) produced by microorganisms like Pseudomonas and Alcaligenes isolated from soil samples in automobile repair workshops in Ilorin. Soil samples were collected from twenty-one (21) randomly selected mechanic workshops across the three local government areas in Ilorin. Physicochemical examination of the sampled soil as well as isolation of bacteria from the soil was done using Pseudomonas isolation Agar after which biochemical tests were performed on the isolated bacteria. The organisms were identified using molecular tools. Isolated Pseudomonas species and Alcaligenes species were screened for biosurfactants production using various screening methods, including haemolytic assay (α-, β-, and γ) and emulsification index. The results were statistically analyzed using one-way ANOVA and Duncan’s test (p < 0.05). Obtained results are: soil pH (6.03-7.50), electrical conductivity (2.19-90.71), organic carbon (0.78-1.63), organic matter (1.23-7.11), sand (6.47-84.6), silt (5.77-16.04) clay (5.07-12.24) and moisture content (11.3-14.10). Levels of significant differences (p < 0.05) were observed statistically. Among the seven isolates onlyPseudomonas aeruginosa-PQ6 was γ-haemolytic. For drop collapse assay, Alcaligenefaecalis-CPO6 showed no reaction. Three of the seven bacterial isolates exhibited the highest emulsification activity: Alcaligenes faecalis-CPO1 (67% Petrol, 65% Engine-oil, 64% Kerosene), Pseudomonas aeruginosa-OR9 (60% Petrol, 67% Engine-oil, 63% Kerosene) and Pseudomonas aeruginosa-MH7 (71% Petrol, 65% Engine-oil, 64% Kerosene). They show promise as biosurfactant producing bacteria. The effective isolates can be utilized for biosurfactant production as sustainable alternatives to synthetic surfactants and hence will help to clean up oil polluted environment.
Prevalence of helminthiasis among some primary school pupils in Yenogoa Local Government Area of Bayelsa State, Nigeria
This study investigated the prevalence of helminthiasis among some primary school pupils in Yenagoa Local Government Area of Bayelsa State, Nigeria. Faecal stool samples were collected and analyzed for the prevalence of helminthiasis according to standard techniques. Of the 500 faecal samples analyzed, an overall prevalence of 39% helminthiasis was recorded. The Community Primary Schools in Kpansia, Aguadama-Epie, Edepie, Amarata and Swali had prevalence of 52%, 41%, 38%, 35% and 29% respectively. The prevalence of helminthiasis in male and female pupils were 66% and 27.4%, respectively. Three parasite species namely, Ascaris lumbriciodes (17.6%), Ancylostoma duodenale (13.2%) and Trichuris trichiura (8.2%) were identified. In all the sampled primary school population, pupils that were 5-6 years of age had the highest prevalence of 51.7% while the group aged 15 and above had the lowest of 29.2%. The age difference in relation to occurrence of helminthiasis was not significant (p > 0.05). In all, the prevalence of helminthiasis among the pupils of Yenagoa LGA of Bayelsa State is high with more occurrence in male pupils than their female counterpart. Therefore, proper hygiene, mass deworming, orientation programmes on helminthiasis in primary schools be put in place to curb this menace which could be of economic and health burden for the pupils, their parents and the State at large.
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A comparative study of gelatin and dextran as sedimentation agents for neutrophil isolation during myeloperoxidase purification
Myeloperoxidase (MPO), a haem-containing enzyme abundant in human neutrophils, significantly contributes to host defense and serves as a biomarker in cardiovascular and inflammatory diseases. Conventional purification methods employ dextran sedimentation for neutrophil isolation; however, dextran is costly and often unavailable. This study compared a gelatin-based sedimentation approach with the conventional dextran method to evaluate the suitability of gelatin as a cost-effective alternative for the purification of myeloperoxidase (MPO) from whole venous blood. Gelatin was used instead of dextran for neutrophil sedimentation before Ficoll centrifugation and hypotonic lysis of contaminating erythrocytes. A myeloperoxidase-rich fraction was prepared from whole neutrophil via selective salt precipitation, and the enzyme activity yield and specific activity were determined. The gelatin-based procedure produced MPO with a specific activity of 5.12 U/mg, 4.7-fold purification, and 42% yield, closely comparable to the 5.41 U/mg, 4.8-fold, and 43.2% values obtained using dextran. The Reinheit Zahl (RZ) value also showed parallel progression (0.39 vs. 0.43), confirming comparable purity. These findings demonstrate that gelatin is a viable, efficient, and economical substitute for dextran in neutrophil sedimentation during MPO purification. The method provides a reproducible, cost-effective approach for laboratories in developing economies to obtain high-quality MPO suitable for biochemical and diagnostic applications.