FACULTY OF LIFE SCIENCES

Tomato is an economically important fruit in Nigeria. Tomato has a high amount of water which makes them more susceptible to spoilage by the action of various microorganisms. The aim of this study was to achieve the bacteriological quality of tomato fruit puree product preserved and treated with sodium metabisulphite under anaerobic condition. Tomato fruits were purchased at Okoko’s village farm, Ovia North East Local Government Area, Edo state and blended into tomato puree. The tomato puree samples were treated with differing concentrations (0, 0.1, 0.2, 0.3, 0.4 and 0.5g/l) of sodium metabisulphite pasteurized at 65 0C for 15 minutes and then stored for 21 days under anaerobic conditions and analysed at every 7 days interval. The analysis carried out were Total Heterotrophic bacteria, Coliform and Salmonella Shigella count, as well as lycopene content, ascorbic content and changes in pH. From the result, the highest heterotrophic bacteria count was 23±2.8310 4cfu/ml, while the lowest was 1±1.41x10 4cfu/ml from puree sample treated with 0 and 0.5g/l of metabisulphite respectively. The highest lycopene content was 22.01±0.1510 4cfu/ml while the lowest was 7.71±0.15x10 4cfu/ml from puree sample treated with 0 and 0.2g/l of metabisulphite respectively. The identified isolates were: Klebisella pneumoniae, Staphylococcus aureus, Pseudomonas aeruginosa, Enterobacter cloacae, Serratia marcescens, Salmonella typhi, Salmonella paratyphi, Escherichia coli, Pseudomonas putida, Proteus vulgaris, Proteus mirabilis and Citrobacter sp. From this study, both pasteurization and preservation by sodium metabisulphite has shown potential as effective ways of prevention against spoilage in tomatoes.

This research was undertaken in order to investigate the bacteria associated with locally processed juices and screen for their sensitivity to antibiotics and chitosan. Tigernut milk, zobo and ginger lemon juice samples were purchased from three (3) different shopping malls in Benin City and transported to the laboratory for bacteriological analysis using pour plate isolation method. Susceptibility of bacteria to antibiotics was carried out using disc diffusion method. Antimicrobial activity of chitosan against isolated organisms was carried out using agar well diffusion method. Total bacterial count on nutrient agar ranged from 13.5×10 3cfu/ml for zobo drink (ZN) to 114×10 3cfu/ml for tigernut milk (TNMFJ). On eosin methylene blue agar, total bacterial count ranged from 5×10 3cfu/ml for zobo drink (ZN) to 52×10 3cfu/ml for tigernut milk (TNMN). Organisms isolated include Lactobacillus fermentii, Staphylococcus spp and Salmonella spp. While Lactobacillus fermentii was the least prevalent (60%), Salmonella spp was the most prevalent (100%). The pH ranged from 3.56 in zobo drink (ZN) to 4.78 in tigernut milk (TNMFJ). Tigernut milk (TNMF) had the highest value of total dissolved solids (2.27mg/ml) while ginger lemon juice (GLN) had the least (0.10mg/ml). The titratable acidity of juice samples ranged from 0.02mg/L in zobo juice (ZN) and ginger lemon juice (GLN) to 0.48mg/L in tigernut milk (TNMFJ). The bacterial isolates showed various levels of sensitivity and resistance to a variety of ten (10) antibiotics. Antimicrobial effects of chitosan against Staphylococcus spp and Salmonella spp showed that Salmonella spp was more susceptible to chitosan at a concentration of 25mg/ml. The results indicate that locally processed juices were contaminated with bacterial isolates and should be subjected to good manufacturing practice (GMP). The inhibitory effect of chisotan show it as a potential preservative in food.

This study was conducted to investigate the dose relationship between thyroid hormone parameters in exposed juveniles of Clarias gariepinus and Cypermethrin using Thyroid function tests. Measuring the levels of Triiodothyronine (T3), Thyroxine (T4), and Thyroid Stimulating Hormone (TSH) are not only critical for diagnosing thyroid problems, but also in differentiating between a primary and secondary cause of a thyroid condition, for instance, an exposure to cypermethrin leading to hypothyroidism. The experimental fishes were exposed to 0, 15, 30, and 45µg/l of Cypermethrin fo96 hours in an acute toxicity experiment. At the end of the 96 hours, muscle tissue samples were harvested and prepared for biochemical analyses using standard procedures. Findings from this study confirm that cypermethrin is an Endocrine Disrupting Chemical (EDC) in fish and alters the thyroid hormone levels in C. gariepinus by targeting the hypothalamus-pituitary-thyroid axis. Furthermore, it provokes the inhibition of thyroid function in the fish so that the activity levels of T3 and T4 reduced significantly (p < 0.05). The levels of TSH increased in a dose-dependent trend, CYP 3 (0.85±0.05) > CYP 2 (0.81±0.01) > CYP 1 (0.75±0.05). A disruption in the normal thyroid function of the fish could impede the regulation of liver glycogen, protein metabolism, cell respiration, antioxidant system and the excitability of neurons and muscles, ultimately leading to deformities in juvenile fish and eventual death

Honey, a natural sweetener and viscous substance produced by honeybees, has been used in human nutrition and traditional medicine for centuries. However, honey can become c health risks to consumers. This study aimed to assess the bacteriological quality of honey sold in two markets in Benin City, Edo State. Honey samples were collected from both markets using sterile containers and transported under controlled conditions to the laboratory. The microbial quality was analyzed by culturing
the samples on nutrient agar and MacConkey agar, followed by bacterial isolation, identification, and biochemical characterization (e.g., Gram staining, catalase, oxidase, indole, citrate, and other biochemical tests). Results showed heterotrophic bacterial counts ranging from 4.0×10⁴ to 5.0×10³ cfu/ml and coliform counts from 1.0×10³ to 4.0×10³ cfu/ml. The highest bacterial contamination was found in Oba Market, while Uselu had the highest coliform count. Clostridium sp. was the most frequently occurring bacterium (25%).The presence of potentially harmful bacteria suggests contamination during production, handling, or storage, raising concerns about honey safety. The study highlights the need for improved hygiene practices and stricter quality control measures to ensure consumer safety

Curtains give seclusion, lessen the quantity of light that enters a room, and enhance the
interior design of a space. The aim of this research project is to conduct bacteriological
assessments of curtains in school hostels. Before sample collection, students` consent was
sought. Fifty samples (50) of curtains were collected from students in the study. Questionnaires were administered to students whose curtains were sampled for
bacteriological analysis. The data obtained from this research were analyzed using statistical
analysis. Antibiotic susceptibility testing was carried out as well as pathogenicity testing. Heterotrophic bacterial counts (log10 Cfu/cm2) of curtains ranged from 2.59 to 2.74 Cfu/cm2
. Four bacteria isolates were identified in this study; Staphylococcus aureus (29.41%), Serratia
marcescens (17.65%), Pseudomonas aeruginosa (23.53%) and Bacillus subtilis (29.41%). Multiple antibiotic resistance index of bacterial isolates ranged from 0.25 to 0.50, indicating
their potential public health implications as these values were above the permitted limit of 0.2. This study shows that curtains can be contaminated with bacteria. The microbiological
burden on curtains can be greatly reduced by taking easy steps like routine cleaning, good
ventilation, and the use of antimicrobial treatments, which will result in a better atmosphere
for all inhabitants.

This dissertation focused on the effects of zinc oxide nanoparticles (ZnO NPs) on the African
catfish (Clarias gariepinus) embryotoxicity. The total protein levels in the embryos of Clarias
gariepinus were determined following a standard method after exposure to different
concentrations (0.0, 0.5, 1.0, 5.0, and 10.0 µg/L) of ZnO NP for 96 hours. The results showed
that there was a minor increment in the total protein levels at the exposure of Clarias gariepinus
embryos to 0.5 µg/L ZnO NPs and a significant increase in NP concentration at 1 µg/L. The
highest level of the total protein was recorded at the 10.0 µg/L concentration exposure of the
ZnO NP to the embryos. The effect of ZnO NP increases with increasing concentration of the
ZnO NP in a dose-dependent manner. Elevated total protein levels imply that there is a possible
inflammation or infection, and this could lead to adverse developmental challenges for the fish
embryos.

Public toilets are dynamic environments affected by both microbial load and indoor air quality from the occupants’ activities. Management at University of Benin faces a challenge when it comes to maintaining satisfactory air quality in the hostel toilets. Regular monitoring is therefore, necessary to evaluate air control effectiveness and to detect the irregular introduction of airborne microorganisms via occupants. The principal aim of this study is to assess the microbial quality of the air in some selected toilets at hall two female hostel, University of Benin by measuring indoor bacterial loads. Samples were collected from Female Student Toilets in Hall 2 Hostel, University of Benin by setting exposed plates for 15minutes. Bacteria were incubated at 37°C for
24hrs. The identified bacterial isolates were Escherichi contamination in the toilet. These findings underscore the importance of thorough cleaning and disinfection protocols in public toilets to minimize the risk of bacterial contamination and
subsequent infections.

This research was conducted with sole aim of investigating the effect of crude oil on the group, morphology and plant based compound of Eichornia crassipes. Samples of the macrophyte were obtained from Ologbo pond in Edo State and transported to the Department of Plant Biology and Biotechnology, where they were used for the experiment conducted in the screen house. The experimental treatments consisted of 0 (control), 0.2, 0.4, 0.6 and 0.8 % v/v. Using a randomized complete block design (RCBD) and three replicates per treatments, the plants were exposed to the treatments for 8 days. E. crassipes samples grown in crude oil showed significant decrease (p<0.01) in all morphological parameters observed. When compared with the control. Wilting, chlorosis and necrosis were observed in some of the plants treated with 0.8 % v/v and 0.6 % v/v.
The plants showed remarkable increase in the accumulation of heavy metals with concentration being more in the roots than in the shoots. Observations obtained in this study revealed that crude oil impact macrophyte parameters at higher concentration levels. The study has shown that E. crassipes can be employed as a tool for biomonitoring of crude oil in fresh water habitats. The study further suggests the need for more intensive research to fully understand the impacts of crude oil pollution on aquatic plants.

The search for extraterrestrial life has been of major concern to scientists as they try to seek for ways by which humans and other living organisms can survive in outer space and beyond. Therefore, studying the effects the space environment could have on living systems and, most likely, finding solutions to these problems has been of great concern to scientists. Microgravity, or the condition of almost zero-gravity, can have profound effects on living systems, including plants and humans. The study design involves subjecting maize seeds to clinorotation condition within a controlled laboratory setup. The experiment was conducted in several replicates, with conventional conditions serving as the control group. The clinostat stimulated micro gravity condition, facilitated continuous rotation of the maize seed, removing the effect of gravitational
force. The effects of microgravity on plants include changes in growth and morphology, changes in nutrient uptake, changes in response to light and changes in gene expression, while the effects on humans include changes in bone density, muscle atrophy, fluid shifts, cardiovascular changes and immune systems changes. Several plants can be used for space explorations. Maize plant can survive in a microgravity environment and can serve as a food source (providing good protein and sugar content), and provide oxygen which can be used by astronauts for long space exploration. The effect of microgravity can could impair the growth and development of the plant, but the use of stimulators like IAA (indole-3-acetic acid), SNP (sodium nitroprusside) will significantly reduce the effects of microgravity environment on zea mays during long space exploration. Understanding these effects is important for developing effective countermeasures to mitigate their negative effects and ensure the safety and health of astronauts in space.

Male infertility represents a significant global health concern, often linked to reproductive damage caused by medications. This study investigated the possible therapeutic benefits of aqueous Hibiscus sabdariffa extract in mitigating reproductive toxicity triggered by inhibitor (SSRI), was used to establish a model of drug-induced male infertility by disrupting sperm parameters. Following the induction of damage, the subjects received treatment with the aqueous extract to evaluate its restorative effects on sperm count, motility, morphology. The findings revealed that treatment with 250mg/kg b.wt of Aqueous Hibiscus sabdariffa extract significantly reduced the damage caused by paroxetine, demonstrating notable enhancements in all evaluated sperm parameters and supporting the recovery of reproductive tissue architecture. These results imply that the bioactive compounds present in the aqueous extract of Hibiscus sabdariffa may offer meaningful protective and restorative benefits against drug-induced reproductive issues, yielding a more balanced improvement across the assessed parameters, highlighting it as a promising natural therapeutic alternative for male infertility