FACULTY OF LIFE SCIENCES

Cadmium is a toxic heavy metal pollutant that causes significant reproductive dysfunction in males through oxidative stress and testicular damage. Watermelon (Citrullus lanatus) rind contains bioactive phytochemicals with potential antioxidant properties that may offer protection against heavy metal-induced toxicity. This study investigated the testicular protective effect of hydroethanolic watermelon rind extract against cadmium-induced reproductive toxicity in Wistar rats. Twenty-five male Wistar rats were randomly assigned into five groups of five animals each. Group one served as the control and received distilled water only. Group two received 1 mg/kg
body weight of cadmium chloride in distilled water . Group three was co-administered 1 mg/kg of cadmium chloride and 100 mg/kg of vitamin C as positive control. Groups four and five received
1 mg/kg of cadmium chloride alongside 250 mg/kg and 500 mg/kg of aqueous extract of Citrullus lanatus phytowaste (AECLP), respectively . All treatments were administered orally for sixty consecutive days. On day sixty-one, the animals were fasted overnight, humanely sacrificed, and samples collected. Semen was obtained from the epididymis for sperm analysis including sperm count, motility parameters. Results demonstrated that AECLP at both doses caused severe reproductive toxicity rather than protection, with complete elimination of progressive sperm motility, total loss of sperm viability, and undetectable sperm counts compared to control and
cadmium-only groups. The extract paradoxically enhanced testicular cadmium bioaccumulation, particularly at the higher dose. These findings suggest that watermelon rind extract at the tested
doses exhibits dose-dependent reproductive toxicity, warranting comprehensive safety reevaluation before therapeutic applications in reproductive health

This study was carried out in the southwestern part of Nigeria in Ondo State, which lies within Latitude 7° 09’ 50.1” and 7° 12’ 20.6”N, and the longitude 5° 13’ 30.5”E and 5° 14’ 30.1”, with the aim of assessing the physical, microbial and chemical parameters of the groundwater. Random sampling technique was employed in obtaining water samples from both the surface and groundwater in the study area. A sterilized one liter plastic bottle was used to collect water samples and were immediately transported to the laboratory for physico-chemical and microbial
analysis. A total of ten (10) water samples were collected; seven (7) groundwater samples and three (3) river samples. The physicochemical parameters determined and values obtained are as follows: Electrical conductivity ranged 300 and 960us/cm, Temperature 25.00 to 25.01℃, pHof6.6-9.2 with a mean value of 6.9, TDS shows a mean valve of 25.69mg/l, CODfrom5-18.4mg/liter with mean value of 10.65mg/liter, Turbidity ranged 1.5 to 6.0 NTU with mean valveof1.03NTU, Cl- 106.50 to 426.00mg/l, SO4 2- 0.41 to 2.87 mg/l, TSS shows a mean valueof0.411mg/l, TS 1.33 to 4.33 mg/l, NO3 - 23.73 to 41.48mg/l, Mg ranged from 0.42 to 0.67mg/liter which is within the WHO limit with mean valve of 0.41mg/l, Ca 0.10 to 0.41 mg/l, HCO3- 7.00to 22.00mg/l, Na ranged from 2.8 to 3.9 mg/liter with mean value of 1.47mg/litre, K0.41to1.20mg/l, Mn 0.01 to 0.11 mg/l, Fe 0.01 to 0.02 mg/l, Zn 0.01 to 0.65 mg/l, PO4 - 0.07 mg/l for all locations. Pb showed a mean value of 0. 011mg/litre. Result of analysis revealed that the ground and surface water in the study area appears to be generally potable, due to concentration of heavy metals being mostly under/within the WHO standard regulation. The pH, salinity and electrical conductivity in the study area was moderate. The colour for some samples were brownish–colourless. The presence of microbial organisms in water is from sewages, septic tanks, and animal faeces. The surface water found within the study area is the Ofuso River. The water quality in the study area is generally potabl

Actinomycetes are gram-positive bacteria with high guanine + cytosine content of over 55% in their DNA. They belong to the order Actinomycetales and form an important segment of the microflora of most natural environments. Soils, manures and composts, freshwater bodies such as lakes and river bottoms contain an abundance of these organisms. Actinomycetes are aerobic, spore forming organisms with a distinctive feature of possessing filamentous hyphae that do not normally undergo fragmentation. Due to their phenotypic similarities to fungi, actinomycetes are also known as ray fungi (Chaudhary et al., 2013). Actinomycetes provide an excellent resource for the isolation and identification of therapeutically important secondary metabolites such as, antibiotic, antifungal, antiviral, anticancer, enzyme, immunosuppressant and other industrially useful compounds (Dhawane and Zodpe, 2017). These microbial compounds have been a source of life saving environment for many bacterial and fungal infections. Some effective antibiotics manufactured from actinomycetes includes: penicillin, streptomycin, tetracycline, erythromycin, amphotericin and vancomycin. These microbial natural products are notable not only for their potent therapeutic activities but also for the fact that they frequently pose desirable pharmacokinetic properties required for clinical development (Khasabuli and Kibera, 2014). Antibiotics of actinomycetes origin have a wide variety of chemical structure, including aminoglycosides, β-lactams, antracyclines, tetracycline, nucleosides, peptides, polyenes and actinomycins. Secondary metabolites isolated from soil actinomycetes have also been proven to be potent inhibitors of numerous plant pathogens (Agadagba, 2014). 1 A large number of actinomycetes have been isolated and screened from soil in the past several decades, accounting for 70 80% of relevant secondary metabolites available commercially. It has been estimated that approximately one-third of the thousands of naturally occurring antibiotics have been obtained from actinomycetes (Chaudhary et al., 2013). More than 70% of these antibiotics are attributed to two genera viz., Streptomyces and Micromonospora (Rai et al., 2018). The richness and diversity of actinomycetes present in any specific soil, is greatly influenced by the soil type, geographical location, cultivation and organic matter amongst other factors (Agadagba, 2014). According to the World Health Organization, over-prescription and the improper use of antibiotics has led to the generation of antibiotic resistance in many bacterial pathogens (Kumar et al., 2010). Serious infections caused by microorganisms that have acquired resistance to commonly used antibiotics have become a major global healthcare problem in the 21st century (Jarallah and Rahaman, 2014). Some antibiotics like penicillin, erythromycin, and methicillin which used to be very effective treatment against infectious diseases are now less effective because pathogens are now more resistant to such antibiotics. Antibiotic resistant pathogens such as methicillin and vancomycin resistant strains of Staphylococcus aureus and others cause an enormous threat to the treatment of serious infections. These drug resistant strains emerge more quickly than the rate of discovery of new drugs and antibiotics (Kumar et al., 2010). Also, increase in fungal infection happens because the available antifungal drugs are not very effective in treating fungal diseases. Fungal diseases are often difficult to diagnose and treat because antifungal drugs are often not very effective in the setting of impaired immunity (Casadevall et al., 2002). Candida albicans can develop resistance to antimycotic drugs such as fluconazole which is often used to treat candidiasis. The frequency of multiazole-resistant 2 3 strains belonging to Candida species other than Candida albicans is increasing (Hitchcock et al., 1993)

This study evaluated the effect of different lignocellulosic substrates on the mycelial growth performance of Pleurotus tuberregium and Psathyrella atroumbonata, two indigenous edible mushrooms of nutritional and economic significance in Nigeria. Five agro-residues including oil palm fiber corn straw, corn husk, plantain leaves, and sawdust were prepared as substrates following pasteurization procedures. Pure cultures of Pleurotus tuberregium and Psathyrella atroumbonata were inoculated into the substrates and incubated at 35°C under controlled humidity (75-80%). Mycelial growth parameters, including radial extension, growth rate, and morphological density, were measured at three-day intervals. The results revealed that substrate composition significantly influenced mycelial colonization and growth rate. For Pleurotus tuberregium, plantain leaves supported the highest mycelial extension after three days, followed by oil palm fiber, while corn husk exhibited the least growth. In contrast, Psathyrella atroumbonata recorded its best performance on oil palm fiber and sawdust, with the least growth again on corn husk. Mycelial density and morphology varied across substrates, with dense and woolly growth observed on oil palm fiber and plantain leaves, indicating vigorous metabolic activity, while sparse or thin mycelium was associated with corn husk, reflecting nutrient limitation and structural rigidity. The comparative growth rate analysis showed that Psathyrella atroumbonata (27.06 mm day') grew faster than Pleurotus tuberregium (22.39 mm day'), suggesting species-specific enzymatic adaptation and differential substrate utilization. The study establishes that substrate selection is a critical determinant of mycelial performance in mushroom cultivation. Plantain leaves and oil palm fiber emerged as the most efficient substrates for Pleurotus tuberregium and Psathyrella atroumbonata, respectively, due to their favorable carbon-nitrogen balance, moisture retention, and porosity. The findings highlights the potential of agricultural residues as contributing to both waste reduction and enhanced food.

Environmental pollution from heavy metals in mechanic workshop soils poses serious threat to soil fertility, microbial health and groundwater quality. This study evaluated the bioremediation potential of phosphate solubilizing bacteria (Pseudomonas sp.) and hydroxyapatite in reducing heavy metal concentrations in contaminated soil. The study was carried out in a mechanic workshop in Osasogie, Ugbowo, Benin city, Edo state, Nigeria with four treatments: soil only (O1), soil + phosphate solubilizing bacteria (O2), soil + hydroxyapatite (O3) and soil + phosphate solubilizing bacteria + hydroxyapatite (O4). Microbial count and heavy metal concentrations (iron, copper and arsenic) were tested after 14 days. According to results hydroxyapatite was most effective in increasing the growth of Pseudomonas sp. and in the remediation of soil contaminated with copper and iron while phosphate solubilizing bacteria was the least effective due to the short period of remediation. In conclusion, Pseudomonas sp. and hydroxyapatite showed great promise in cleaning up heavy metal contaminated soil from a mechanic workshop.

Celosia argentea, commonly known as Lagos spinach or “soko yokoto,” is widely used in traditional medicine for the treatment of various ailments such as infections, inflammation, and gastrointestinal disorders. The study investigated the phytochemical constituents and antimicrobial properties of Celosia argentea leaves, a medicinal plant widely used in traditional medicine for treating infections, inflammation and other ailments. Growing concerns over antibiotic resistance have driven research into natural sources of antimicrobial agents, particularly from plants rich in bioactive compounds. The study aimed to qualitatively determine the phytochemical components present in Celosia argentea leaves and to evaluate their antimicrobial activities against selected pathogenic bacteria including Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa. The leaves were collected from Benin City, air-dried, pulverized, and extracted using 50% ethanol. Standard phytochemical tests were performed to identify the presence of secondary metabolites, and antimicrobial sensitivity tests were conducted using the agar disc diffusion method. Results revealed the presence of various phytochemicals such as saponins, terpenoids, flavonoids, alkaloids, glycosides, tannins, and phenols, which are known for their pharmacological significance. However, the aqueous extract of Celosia argentea leaves exhibited weak antimicrobial activity, showing mild inhibition zones (5 mm) only at the highest concentration (1000 mg/ml) against Staphylococcus aureus and Escherichia coli, while no activity was observed against Bacillus subtilis and Pseudomonas aeruginosa. The limited antimicrobial response may be attributed to low solubility orconcentration of active compounds in water. These findings suggest that although Celosia argentea leaves contain significant bioactive components, solvent optimization and concentration adjustments are essential to enhance antimicrobial efficacy. The study concludes that Celosia argentea has promising therapeutic potential and warrants further investigation using organic solvents and advanced analytical techniques for the development of effective plant-based antimicrobial agents.

In Orhionmwon Local Government Area, many residents depend on untreated surface and groundwater sources such as wells, boreholes, and rivers for drinking and domestic use. The quality of these sources had not been scientifically assessed, raising concerns about their suitability for human consumption. The area faces growing contamination from agricultural runoff, poor waste disposal. These factors can introduce harmful substances like nitrates, phosphates, and heavy metals into drinking water sources. Consuming contaminated drinking water can cause diseases such as cholera, typhoid, and diarrhea, and long-term exposure to toxic metals like lead orchromium can result in neurological and kidney damage. Hence, there was a need to determine if water from these sources posed such health risks. This study assessed the physicochemical quality of drinking water from selected sources in Orhionmwon Local Government Area, Edo State, Nigeria. Water samples were collected from five sites comprising two boreholes, two hand-dug wells, and one river. A total of twenty-three physicochemical parameters were analysed, including pH, turbidity, electrical conductivity, total dissolved solids (TDS), total suspended solids (TSS), nitrate, sulphate, phosphate, dissolved oxygen (DO), biochemical oxygen demand (BOD), chemical oxygen demand (COD), total hardness, alkalinity, and several heavy metals (Fe, Cu, Zn, Ni, Pb, Mn, Cr, etc.). Analytical methods were based on APHA standard procedures and results were compared with Nigerian Industrial Standard (NIS 977:2017) and WHO permissible limits. The findings revealed that pH values across all water sources were below the acceptable range (6.5–8.5), indicating acidic water with potential for corrosiveness and metal leaching. River water showed elevated turbidity, BOD (3.8 mg/L), and COD (38.0 mg/L), suggesting organic pollution. Lead and chromium levels in the river exceeded regulatory limits, posing potential health risks. Borehole water generally exhibited the best quality, while the river was the most contaminated source. Most other parameters, including nitrate, sulphate, chloride, and iron, were within permissible limits.These results
indicate that while some water sources are suitable for consumption, others, particularly the river, require urgent intervention and treatment. The study recommends regular monitoring, pH correction, community sensitization, and infrastructure improvement to ensure the provision of safe drinking water in Orhionmwon.

Ocimum gratissimum essential oil comes from the plant, commonly called African basil or Clove basil. It is indigenous to mainly Africa. However, they have been found in other tropical and subtropical parts of the world, like Southern Asia and America (Ezeorba et al., 2024). The African basil is a perennial herb. It is woody at the base with an average height of 1–3 m, many branches, broad leaves and narrow ovate. It is a plant propagated through seed planting and stem cutting and is well-known for its aromatic nature, hence its name, “scent leaf” in Nigeria and some West African countries (Ezeorba et al., 2024). Ocimum gratissimum is known by various names in different parts of the world. In India it is known by its several vernacular names, the most commonly used ones being Vriddhutulsi
(Sanskrit), Ram tulsi (Hindi), Nimma tulasi (Kannada). In the southern part of Nigeria, the plant is called “effinrin-nla” by the Yoruba speaking tribe. It is called “Ahuji” by the Igbos, while in the Northern part of Nigeria, the Hausas call it “Daidoya” (Prabhu et al., 2009).

Pesticide contamination in aquatic organisms poses a growing concern for both food safety and environmental health. This study evaluated the effect of boiling on the residual levels of organochlorine and organophosphate pesticides in the African freshwater prawn (Macrobrachium vollenhovenii) obtained from markets in Benin City, Edo State, Nigeria. Prawn samples were collected from Uselu and Oba markets in August 2025. Pesticide residues were extracted and analysed using Gas Chromatography–Mass Spectrometry (GC–MS). Results showed that twenty (20) organochlorine and fourteen (14) organophosphate pesticide residues were detected in both raw and boiled prawn samples. The total concentration of organochlorines decreased from 28.42 ppb in raw samples to 23.845 ppb after boiling, indicating a slight reduction following heat treatment. Conversely, organophosphate pesticide levels increased from 8.595ppb in raw prawns to11.405ppb in boiled samples. Among organochlorines, α-HCH, β-HCH, PP‘-DDT were eliminated after boiling while Gamma-Chlordane, Alpha chlordane, PP‘-DDD, Methoxy For organophosphates, Chlorpyrifos (2.405 ppb) and Phosalone (1.58 ppb) showed notably higher levels of post-boiling, whereas Isazophos and Pyrazophos were completely degraded. For both pesticide groups, the estimated daily intake (EDI) for local consumers, based on an average prawn consumption rate of 0.33 kg/day and a 60 kg adult body weight for both the raw and boiled samples, were below the acceptable daily intake (ADI), indicating minimal potential health risks. Similarly, the hazard quotient (HQ) and hazard index (HI) values for both pesticide groups were less than one (<1) for both the raw and boiled samples, implying low non￾carcinogenic and carcinogenic risk to consumers. When compared with the FAO/WHO Codex and EU maximum residue limit (0.01 mg/kg for seafood), the total concentrations of organochlorine pesticides (0.028 mg/kg) exceeded the acceptable limit, indicating potential xiii xiv contamination risks. These findings suggest that while boiling can reduce certain persistent organochlorine residues, it may also increase the apparent concentration of some organophosphate pesticides. Continuous monitoring and further investigation into the effects of cooking methods on pesticide dynamics are recommended to safeguard consumer health.

Access to safe drinking water remains a critical public health challenge in rural communities of Nigeria. This study assessed the microbial quality and potential health risks associated with drinking water from multiple sources in Orhionmwon Local Government Area (LGA), Edo State. A total of five water samples were collected, comprising two boreholes, two hand-dug wells, and Ikpe River Samples were analysed using the pour plate method for total heterotrophic bacterial count (THBC), total coliforms, Escherichia coli, and fungi, followed by biochemical identification of isolates. Results revealed bacterial loads ranging from 13 cfu/ml in borehole samples to 5.9 × 10³ cfu/ml in river water, exceeding the World Health Organization (WHO, 2022) limit of 500 cfu/ml for drinking water. E. coli and coliforms were detected in the river and one well sample, indicating fecal contamination, while borehole water remained within permissible standards. Isolated bacterial species included Bacillus spp., Pseudomonas aeruginosa, Proteus spp., Klebsiella spp., Enterobacter spp., and E. coli, while fungal isolates comprised Aspergillus spp., Mucor spp., Penicillium spp., and Rhodotorula spp. The presence of these organisms, particularly fecal indicators and opportunistic pathogens, underscores potential risks of waterborne infections in the area. The study highlights the need for regular microbial surveillance, improved sanitation practices, and promotion of household water treatment methods such as boiling or chlorination to ensure safe drinking water and protect community health.