FACULTY OF LIFE SCIENCES

Carrot (Daucus carota) is one of the most important economical root vegetable crops worldwide and the largest source of provitamin A and carotenoids in the human diet. Storage is a prerequisite for a year-round supply of Carrot, but longer duration can affect its quality. Essential oils also has diverse and relevant biological activities. This study was aimed towards isolating the bacteria associated with rotted carrot, characterizing and isolating three bacteria isolate and determining the antibacterial properties of selected essential oils against the isolates using Agar well diffusion method. Suspected bacteria pathogens were isolated from a diseased carrot tuber, the isolates were identified using biochemical and cultural characterization. Essential oils were used in the antimicrobial sensitivity treatment using agar well diffusion method against the isolated bacteria to determine the antibacterial property of the essential oils. The results showed that Enterobacter sp., Pseudomonas sp. and Agrobacterium tumenfacienwere the isolated pathogenic bacteria from the carrot tubers. The essential oils which are (Neem oil, Tea tree oil and Bergamot oil), showed no antibacterial activity on the isolated bacteria pathogens. Further investigations can be done using essential oils against bacterial isolates but it should be extracted from the plant source to avoid destroying its potential antimicrobial properties.

This study focused on isolating and identifying fungal species associated with agricultural farmland soil in UNIBEN. Soil samples were collected in sterile plastic ziplock bags from selected agricultural farmlands in Benin City, Edo State, and were subsequently transported to the laboratory for fungal identification. The identification of fungal isolates was conducted using cultural and morphological methods. The results indicated that total fungal counts of soil samples collected from the selected farmlands ranged from 5.70±0.42 to 12.50±1.56. The highest fungal counts were observed in Farm 2 (12.50±1.56), followed by Farm 5 (8.70±0.71), while Farm 4 exhibited the lowest count at 5.70±0.42. The identified fungal isolates included Aspergillus niger, Trichoderma sp., Penicillium sp., Rhizopus arrhizus, and Mucor mucedo. The percentages of occurrence for these fungal isolates varied from 7.14% to 28.57%. Aspergillus niger had the highest occurrence rate at 28.57%, followed by Trichoderma sp. and Penicillium sp., each at 21.43%, while Rhizopus arrhizus had the lowest occurrence at 7.14%. This study emphasizes the importance of understanding the dynamics of fungal populations within these agricultural soils to inform management strategies aimed at enhancing soil health. By monitoring these microbial communities, farmers at these sites can adopt more effective agronomic practices that capitalize on beneficial fungi while minimizing the impact of pathogenic species.

Antimicrobial resistance (AMR) poses a significant public health threat, enabling bacterial strains to withstand common antimicrobial therapies. This study aimed to determine the prevalence and antibiotic resistance patterns of hospital-acquired Escherichia coli infections among children admitted to a tertiary hospital in Benin City, Nigeria. This was a cross-sectional study conducted from August to October 2025. A total of 80 swab samples were processed using standard culture-based methods. Bacterial isolates were identified via cultural characteristics, Gram staining, and standard biochemical tests (Catalase, Oxidase, Citrate, Indole, VogesProskauer, Hydrogen Sulphide, Methyl red, Urease and Sugar Fermentation). Antimicrobial susceptibility testing (AST) was performed using the Kirby-Bauer disc diffusion method. The antibiotics tested included ceftriaxone, ceftazidime, ciprofloxacin, gentamicin, amoxicillin-clavulanic acid and meropenem. The Patient demographics showed a clear difference, with the highest number recorded among male in-hospital patients (44) and the lowest among female community patients (4). Organism distribution varied by sample site, where Escherichia coli was the dominant isolate in rectal samples (17 isolates). Testing against a panel of 19 antibiotics revealed that most E. coli isolates remained susceptible. The highest resistance was observed against sulfamethoxazole-trimethoprim (7 isolates). Multidrug resistance patterns were diverse, with the combination of ciprofloxacin, piperacillin, and sulfamethoxazole (CIP, PIP, SUL) being the most frequently observed MDR profile (in 2 isolates). These findings align with previous reports from Nigerian hospitals, emphasizing the need for improved antimicrobial stewardship, routine resistance monitoring, and strict infection prevention measures to reduce hospital-acquired infections and ensure effective patient care.

Heavy metals are ubiquitous contaminants in the aquatic ecosystems, posing significant threats to fishes and other aquatic fauna which tend to bioaccumulate this toxicant in their muscle. This study was therefore carried out to investigate the bioconcentration of heavy metals in the muscles tissues of fish fauna within Ikpoba River, Benin city. A total number of 26 (13 Clarias garipienus and Tilapia zilli) fishes were collected from Ikpoba River between June to August 2023. Heavy metals (Cd, Ni, Pb, Cr and Co) in the muscles of the fish were estimated using atomic absorption spectrometer (AAS), while the ratio of heavy metals in the muscles of the fish
relative to water, was estimated using the bioconcentration index. The result showed that Nickel in the muscles of the benthic fish had the highest concentration in the month of June (21.21mg/kg) and lowest in the month of July (14.92mg/kg), while Nickel in the pelagic fish had the highest concentration in August (21.82mg/kg) and lowest in July (12.89mg/kg). Lead and Cadmium were found to be below detectible limit in benthic and pelagic fish muscle tissue across the sampling period. Chromium in the muscle tissue of the benthic fish has the highest in June (10.89mg/kg) and lowest in July (4.85mg/kg), while in pelagic fish, it was found to be highest in August (12.91mg/kg) and lowest in June (6.11mg/kg). The concentration of cobalt in benthic and pelagic fish was found to be highest in the month of August (3.44mg/kg and 12.91mg/kg) and lowest in the month of June (1.93mg/kg and 6.11mg/kg) respectively. These variations therefore signify the level of heavy metal accumulation in their tissues which have impacts on the aquatic ecosystem and human health.

Bacterial and fungal contaminations of borehole water in school hostels is a prevalent issue, particularly in regions where boreholes serve as primary water sources and hygiene practices may be challenging to maintain. This study was aimed at assessing the microbial contamination of water in student’s residential halls in University of Benin, Benin City. The bacterial isolates were characterized and identified using morphological and biochemical methods. The percentage distribution and frequency of the isolates were evaluated using statistical method. From the result obtained in this study, the total heterotrophic bacterial counts ranged from 4.46 log10 cfu/ml to 4.86 log10 cfu/ml, Coliform count ranged from 2.84 to 3.13 log10 cfu/ml and fungal counts ranged from 4.40 to 4.85 log10 cfu/ml. Using the cultural, morphological and biochemical test, the isolates obtained in this study include, Escherichia coli, Klebsiella sp, Staphylococcus sp, Bacillus sp, Citrobacter, Enterobacter sp, Bjerkandera sp, Aureobasidium sp, Scedosporium sp, and Mucor
sp. The contamination of borehole water in school hostels by various bacterial and fungal pathogens, such as Escherichia coli, Klebsiella, Staphylococcus, Bacillus, Citrobacter, Enterobacter, Bjerkandera sp, Aureobasidium sp, Scedosporium sp, and Mucor sp, presents serious public health risks. These microorganisms, arising from fecal contamination, soil infiltration, and environmental factors, can cause a range of infections, from gastrointestinal illnesses to skin, respiratory, and systemic diseases.

Plants are the most abundant natural primary source of drugs utilized to treat ailment,s and several plants rich in phytochemicals used as medicine have Nigerian origin. Locally, extracts of plants such as roots, stems, flowers, and fruits are used in the treatment of diseases. This study evaluates the antimicrobial potency of leaves of culinary relevant local Nigerian plants; Gongronema latifolium (Utazi) and Gnetum africanum (Okazi) against selected clinically relevant bacterial and fungal species- Staphylococcus aureus, Escherichia coli, Klebsiella sp, Candida sp and Trichophyton sp. It also served to assess the phytochemical constituents that contribute to their effectiveness as antimicrobial agents. The leaves were obtained, identified, pulverized, and then the leaves extracts were prepared with cold water and methanol. The phytochemical composition of the leaves were determined using standard procedures. The antimicrobial potency was evaluated at concentrations of 2000mg/ml, 1000mg/ml, 500mg/ml and 250mg/ml. Ethanolic extracts proved to be more potent demonstrating broader zones of inhibition and bactericidal activity. Gongronema latifolium (Utazi) aqueous extracts demonstrated higher antimicrobial activity compared to their ethanol counterparts against Gram-negative Klebsiella sp (20.00mm) and fungal Trichophyton sp (15.00mm), while Gnetum africanum (Okazi) aqueous extract was more active against Candida sp (15.00mm). The leaf extracts demonstrated only static activity against Escherichia coli and Staphylococcus aureus. This study further reinforces the basis of the use of traditional plants in the treatment of microbial infections. However, future investigation on the mechanism of action, toxicity level is essential to fully optimize the potential of G. latifolium (Utazi) and G. africanum (Okazi) as therapeutic agents in the treatment of infections caused by microorganisms.

Plants are the most abundant natural primary source of drugs utilized to treat ailment,s and several plants rich in phytochemicals used as medicine have Nigerian origin. Locally, extracts of plants such as roots, stems, flowers, and fruits are used in the treatment of diseases. This study evaluates the antimicrobial potency of leaves of culinary relevant local Nigerian plants; Gongronema latifolium (Utazi) and Gnetum africanum (Okazi) against selected clinically relevant bacterial and fungal species- Staphylococcus aureus, Escherichia coli, Klebsiella sp, Candida sp and Trichophyton sp. It also served to assess the phytochemical constituents that contribute to their effectiveness as antimicrobial agents. The leaves were obtained, identified, pulverized, and then the leaves extracts were prepared with cold water and methanol. The phytochemical composition of the leaves were determined using standard procedures. The antimicrobial potency was evaluated at concentrations of 2000mg/ml, 1000mg/ml, 500mg/ml and 250mg/ml. Ethanolic extracts proved to be more potent demonstrating broader zones of inhibition and bactericidal activity. Gongronema latifolium (Utazi) aqueous extracts demonstrated higher antimicrobial activity compared to their ethanol counterparts against Gram-negative Klebsiella sp (20.00mm) and fungal Trichophyton sp (15.00mm), while Gnetum africanum (Okazi) aqueous extract was more active against Candida sp (15.00mm). The leaf extracts demonstrated only static activity against Escherichia coli and Staphylococcus aureus. This study further reinforces the basis of the use of traditional plants in the treatment of microbial infections. However, future investigation on the mechanism of action, toxicity level is essential to fully optimize the potential of G. latifolium (Utazi) and G. africanum (Okazi) as therapeutic agents in the treatment of infections caused by microorganisms.

Ferruginous soils present challenges for plant growth due to their elevated iron levels, which can cause iron toxicity and negatively impact crop productivity. Copper nanoparticles demonstrate potential in mitigating iron toxicity in plants. This research studied maize plants polluted with different copper nanoparticle concentrations in ferruginous soils with elevated iron. The aim was to ascertain maize tolerance to various iron stress levels and its resultant yield. The results indicated improved maize growth with copper nanoparticles, significantly at 35% and 100% concentration in the early and late development phases. This infers a dose- dependent relationship between nanoparticle concentration and maize growth, with higher concentrations conveying increased maize sensitivity to excessive iron levels. The dynamic response of maize to nanoparticles over time emphasizes the need for exposure duration. In week 2, plants polluted with a 35% Cu nanoparticle concentration in soils alleviated at 4 ESV portrayed smaller leaf areas in contrast to those in 2.5 ESV soils. This infers that higher contamination may hamper the nanoparticles' positive leaf area effects. The complex impact of copper nanoparticles on maize morphology was influenced by a combination of factors including concentration, soil contamination, and specific parameters. Plant height, leaf length, leaf width, leaf area, and sheath length were modified by treatment, while blocks substantially affected plant height, leaf length, and sheath length. Copper nanoparticles demonstrate the potential to improve maize resilience in ferruginous soils, presenting a viable sustainable agriculture solutions in iron-rich environments.

ir pollution, particularly fine particulate matter (PM2.5), is a growing environmental and public health concern in urban areas. This study aimed to compare outdoor PM2.5 concentrations during the daytime and nighttime in Benin City, Nigeria. PM2.5 data were collected from three distinct locations (Ugbowo, Sapele Road, and Etete) between October to December 2024 using PurpleAir sensors, with measurements taken six times daily at intervals of 5 hours. Statistical analysis, including paired T-test and ANOVA, was conducted to assess variations between day and night as well as across location and time. Results revealed significantly higher PM2.5 levels during the daytime, with concentrations peaking in December (170.83 µg/m³). The lowest concentration during the day was recorded in the month of October (93.67µg/m³,) while the highest concentration was in the month of December (183.33 µg/m³) at Etete. At night, the least concentration was at Sapele road in the month of October (80.09 µg/m³) with the highest in December (158.32) at Etete. A significant difference (p =1.346e-15) was recorded between the concentrations of daytime and night time PM2.5. A statistical significant difference was tested across locations (p = 0.0088) and months (p = 2e-16). The recorded concentrations far exceed WHO guidelines for PM2.5 concentrations, suggesting a possible health risk for the inhabitants of those locations. Immediate interventions are recommended, including stricter emission regulations, better urban planning, and public awareness campaigns, to mitigate the effects of air pollution and improve public health.

The impact of dietary fats on cardiovascular health is of growing concern, particularly in regions where red palm oil is a staple cooking fat. This study investigates the effect of frying an egg with red palm oil on egg cholesterol levels and its influence on the lipid profile and heart histology of Wistar rats. Sixteen female Wistar rats were divided into four dietary groups fried egg with red oil, raw cholesterol, positive control, and negative control. After 42 days, lipid profile analysis on some lipid (total cholesterol and triglyceride) revealed that the fried egg with red oil group had a total cholesterol level of (251.90 ± 2.64 mg/dL), which was significantly lower than the raw cholesterol group (307.63 ± 7.74 mg/dL). Triglyceride levels also varied, with the fried egg group showing (554.19 ± 9.16 mg/dL), compared to (577.09 ± 9.53 mg/dL) in the raw cholesterol group. Histological analysis of the heart tissues showed vascular stenosis and
perivascular infiltration in the fried egg with red oil group, while the raw cholesterol group exhibited mild perivascular fibroblast mobilization. These results indicate that frying eggs in red
palm oil alters lipid metabolism and affects cardiovascular health, potentially modifying cholesterol bioavailability. The study highlights the significance of cooking methods in influencing dietary cholesterol impact and underscores the need for further research on the longterm effects of palm oil consumption on heart health.