DEPARTMENT OF MICROBIOLOGY

This study was conducted to evaluate the bacteriological and sensory qualities of fresh and packaged mixed fruit salad sold along the Ugbowo axis in Benin City, Edo State. Mixed fruit salad samples were collected from various vendors located near the University of Benin, specifically within the Ekosodin and BDPA areas. Upon collection, the samples were securely placed in sterile zip-lock bags and subsequently transported to the laboratory for bacteriological analysis. The bacteriological assessment was performed using cultural techniques, with the identification of isolates conducted through biochemical methods. Additionally, phenotypic virulence properties of the isolates were evaluated, and antimicrobial sensitivity was assessed using the biodisc diffusion method. The results indicated that the heterotrophic bacterial count of mixed fruit salad samples stored in refrigeration and at room temperature for four hours ranged from 2.50 ± 2.12 x 103 cfu/g to 4.08 ± 1.24 x 105 cfu/g. In contrast, samples kept in refrigeration and at room temperature for 24 hours exhibited a range between 1.51 ± 0.20 x 105 cfu/g to 5.70 ± 0.88 x 104 cfu/g. The Staphylococcus aureus count for samples stored in refrigeration and at room temperature for four hours ranged from 1.57 ± 0.78 x 103 cfu/g to 4.50 ± 0.42 x 102 cfu/g, whereas those kept for 24 hours showed a count ranging from 2.50 ± 0.14 x 103 cfu/g to 8.96 ± 0.23 x 104 cfu/g. The coliform bacteria count in mixed fruit salad samples stored for four hours ranged from 2.34 ± 0.21 x 103 cfu/g to 7.20 ± 0.88 x 102 cfu/g, compared to samples stored for 24 hours which exhibited counts ranging from 2.50 ± 0.14 x 103 cfu/g to 8.96 ± 0.23 x 104 cfu/g. The percentage frequency of occurrence of bacterial isolates was as follows: Staphylococcus aureus (12%), Bacillus megaterium (12%), Lactobacillus spp. (12%), Serratia marcescens (6%), Flavobacterium spp. (10%), Enterobacter cloacae (8%), Micrococcus lactis (2%), Bacillus cereus (10%), Staphylococcus warnei (2%), Enterococcus faecium (8%), Bacillus thuringiensis (8%), Salmonella arizonae (4%), Bacillus licheniformis (2%), Klebsiella pneumoniae (2%), and Bacillus subtilis (2%), respectively. The findings of this study underscore the necessity for further research aimed at developing effective strategies for mo itoring and mitigating microbial hazards in ready-to-eat foods, thereby safeguarding consumer health against potential outbreaks associated with antibiotic-resistant bacteria.

This study accessed the microbial analysis of melon seeds purchased from different vendors in New Benin market, Ogida market, Oba market and Uselu market in Benin City, Edo state, Nigeria. Samples were collected in sterile plastic containers and taken to the laboratory for microbiological assessment following standard procedures. The microbiological assessment was carried out using cultural techniques. Identification of the microbial isolates was done using biochemical methods, phenotypic virulence properties were evaluated for the isolates and antimicrobial sensitivity was carried out using agar well diffusion method. The results showed that the bacterial counts ranged from 1.96±0.67 to 3.45±1.15x105 CFU/g. The total coliform counts ranged from 4.73±0.67 to 9.66±0.67 x103 CFU/g. The fungal counts ranged from 1.00±0.00 to 6.00±0.58x103 CFU/g. The bacterial isolated from the melon seed samples were Bacillus sp, Escherichia coli, Pseudomonas sp and Staphylococcus aureus. The fungal isolates identified were Aspergillus flavus, Aspergillus niger, Rhizopus sp, Penicillium chrysogenum, Fusarium sp and Trichoderma sp respectively. The antibacterial susceptibility testing showed that all isolates were susceptible to ciprofloxacin, erythromycin and levofloxacin but were also resistant to pefloxacin, gentamycin, ampiclox, zinnacef, amoxicillin and rocephin. It was also evident that all isolates were found to have an MAR index greater than 0.2 which means that the isolates were all pathogens of public health importance. The study therefore suggests regular surveillance and checks to monitor local vended foods on sale to ensure effective food safety.

This study accessed the microbial analysis of melon seeds purchased from different vendors in New Benin market, Ogida market, Oba market and Uselu market in Benin City, Edo state, Nigeria. Samples were collected in sterile plastic containers and taken to the laboratory for microbiological assessment following standard procedures. The microbiological assessment was carried out using cultural techniques. Identification of the microbial isolates was done using biochemical methods, phenotypic virulence properties were evaluated for the isolates and antimicrobial sensitivity was carried out using agar well diffusion method. The results showed that the bacterial counts ranged from 1.96±0.67 to 3.45±1.15x105 CFU/g. The total coliform counts ranged from 4.73±0.67 to 9.66±0.67 x103 CFU/g. The fungal counts ranged from 1.00±0.00 to 6.00±0.58x103 CFU/g. The bacterial isolated from the melon seed samples were Bacillus sp, Escherichia coli, Pseudomonas sp and Staphylococcus aureus. The fungal isolates identified were Aspergillus flavus, Aspergillus niger, Rhizopus sp, Penicillium chrysogenum, Fusarium sp and Trichoderma sp respectively. The antibacterial susceptibility testing showed that all isolates were susceptible to ciprofloxacin, erythromycin and leofloxacin but were also resistant to pefloxacin, gentamycin, ampiclox, zinnacef, amoxicillin and rocephin. It was also evident that all isolates were found to have an MAR index greater than 0.2 which means that the isolates were all pathogens of public health importance. The study therefore suggests regular surveillance and checks to monitor local vended foods on sale to ensure effective food safety

This study was aimed at determining fungal contaminants in Fried bean cake sold in four Local Government Area across Benin metropolis. A total of twelve (12) samples were analyzed using standard microbiological procedures. The fungal population was isolated and identified based on its cultural and morphological characteristics. The fungi isolated were Penicillium chrysogenum, Mucor mucedo, Aspergillus flavus, Saccharomyces sp. and Fusarium oxysporium. The mean fungal count ranged from 3.7 ×10 4cfu/g to 1.3 ×10 4 cfu/g and the prevalence of these fungal isolates ranged from 33.33% to 8.33%. Though the sample does not exceed the mean microbial count recommended standard of 10 5 cfu/g for ready-to-eat foods and the total fungal count of 10⁴ cfu/g for food. There might have been hygienic problems either in the processing, handling and distribution of the food. It is therefore encouraged that proper hygienic procedures are followed in the processing and handling of food to prevent the spread of microorganisms and its toxins that are of public health importance

The research was carried out to evaluate the spoilage microorganisms of tomatoes sold in Benin City. Standard bacteriological methods were used to enumerate the total bacterial and fungal count of the tomatoes using pour plate methods after serial dilution. The bacterial isolates were characterized and identified using morphological and biochemical methods and sugar fermentation test. The percentage distribution and frequency of the isolates were evaluated using statistical method. The result obtained in this study showed that the highest bacterial, coliform and fungal population was obtained in Adolor sample with values of 6.07554±1.00, 5.09691±0.5 and 4.767155±0.5 log10 cfu/g respectively while the least bacterial, coliform and fungal count was obtained from Uselu and Ekosodin samples with values of 5.35218±2.00, 3.69897±1.00 and 4.32221±1.00 log10 cfu/g respectively. Using the cultural and morphological characteristics, the fungal isolates obtained in this study were Aspergillus niger, Trichoderma sp, Penicillium sp and Rhizopus arrhizus while the bacterial isolates obtained were Escherichia coli, Bacillus sp, Salmonella sp, Shigella sp, Klebsiella sp and Staphylococcus sp. From the result, isolates were resistance to many of the antibiotics including, collistin, Erytromycin, metronidazole and clindamycin but were susceptible to ciprofloxacin, augmentin and gentamycin. The result in this study has shed light into the gaining of entrance of food borne pathogens as well as some spoilage microorganisms (mostly fungi) during selling, harvesting and cultivation which may result in food poisoning.

This study accessed the microbial analysis of melon seeds purchased from different vendors in New Benin market, Ogida market, Oba market and Uselu market in Benin City, Edo state, Nigeria. Samples were collected in sterile plastic containers and taken to the laboratory for microbiological assessment following standard procedures. The microbiological assessment was carried out using cultural techniques. Identification of the microbial isolates was done using biochemical methods, phenotypic virulence properties were evaluated for the isolates and antimicrobial sensitivity was carried out using agar well diffusion method. The results showed that the bacterial counts ranged from 1.96±0.67 to 3.45±1.15x10 5 CFU/g. The total coliform counts ranged from 4.73±0.67 to 9.66±0.67 x10 3 CFU/g. The fungal counts ranged from 1.00±0.00 to 6.00±0.58x10 3 CFU/g. The bacterial isolated from the melon seed samples were Bacillus sp, Escherichia coli, Pseudomonas sp and Staphylococcus aureus. The fungal isolates identified were Aspergillus flavus, Aspergillus niger, Rhizopus sp, Penicillium chrysogenum, Fusarium sp and Trichoderma sp respectively. The antibacterial susceptibility testing showed that all isolates were susceptible to ciprofloxacin, erythromycin and levofloxacin but were also resistant to pefloxacin, gentamycin, ampiclox, zinnacef, amoxicillin and rocephin. It was also evident that all isolates were found to have an MAR index greater than 0.2 which means that the isolates were all pathogens of public health importance. The study therefore suggests regular surveillance and checks to monitor local vended foods on sale to ensure effective food safety

Shigella flexneri, a leading cause of bacillary dysentery, induces severe gastrointestinal inflammation, disrupting gut homeostasis. This study evaluates the potential of Lactobacillus
casei as probiotics to enhance immune responses in Wistar albino rats against Shigella flexneri infection. Forty healthy Wistar rats were divided into five groups: Control, challenged (Shigella flexneri-infected), Probiotic (Lactobacillus casei-treated), Prophylactic (pre-treated with Lactobacillus casei before infection), and Antibiotic (ciprofloxacin-treated). Stool samples were collected from rats prior to induction with shigella flexneri and Lactobacillus casei, after induction with Shigella flexneri, and antibiotic treatment. Approximately 1g of stool was homogenized in 9 mL of sterile PBS using a vortex mixer to ensure thorough dispersion. A tenfold serial dilution was performed by transferring 1 mL of the stool homogenate into 9 mL of sterile PBS, creating dilutions from 10' to 10-6. From the 1 dilution, 0.1 mL was plated onto Nutrient agar plates and incubated at 37°C for 24hrs

Soil actinomycetes are recognized as promising sources of new antimicrobials. Antimicrobial resistance in pathogens has greatly increased in recent years, and has become a global public health problem. New antimicrobials are continuously required to combat these resistant strains. The aim of this study was to isolate and screen soil actinomycetes and evaluate their secondary metabolites for antimicrobial activities against selected pathogenic bacteria and fungi. Four soil samples were collected, pre-treated with CaCO3, serially diluted and spread plated on actinomycetes isolation agar (AIA) and international streptomyces project media 2 (ISP-2), supplemented with nystatin, neomycin and polymyxin B . Perpendicular streak method was used to check antagonistic activities of the isolated actinomycetes against test microorganisms. Small scale submerged fermentation system was used for the production of antimicrobial metabolites from the isolates. Agar well diffusion was then used to evaluate antimicrobial activities of the crude extracts against the test microorganisms. The average aerobic actinomycetes plate count from the different soil samples ranged from 3.0×10 4 ± 2.4 to 3.6×10 4 ± 1.9 CFU/g. A total of 28 different microorganisms were isolated, characterized by cultural and morphological methods and identified as actinomycetes. Out of the 28 isolates, 10 (36%) showed antimicrobial activities on primary screening; from which isolates BYQ3, CYP1, CYP2, CYP4 and CYQ2 were selected for their wide spectrum of activities. Diameters of inhibition zones produced by these 5 isolates against the test microorganisms on secondary screening, ranged from 0 to 26 mm. Isolates CYP1 and CYP2 had the widest zones with CYP1 producing 26 mm against Candida albicans. The two promising isolates were further characterized by physiological and biochemical tests and identified as genus Streptomyces. Isolate CYP1 was then identified to the specie level by 16S rRNA gene sequence analysis which confirmed that Streptomyces sp. CYP1 was homologous to Streptomyces albus (strain DSM 40313) of the order Actinomycetales and class Actinobacteria. Optimization of production conditions, further purification, structural elucidation and characterization are recommended to know the quality, novelty and commercial value of these antimicrobials key words

Urinary tract infections (UTIs) are among the most frequently encountered bacterial
infections globally, particularly prevalent among young adults such as university students. Risk factors including poor hygiene practices, sexual activity, and limited access to timely healthcare contribute significantly to the occurrence of these infections. This study was designed to investigate the prevalence of Methicillin-resistant Staphylococcus aureus (MRSA) and other uropathogenic bacteria in urine samples of selected students from the University of Benin. A total of 60 midstream urine samples were aseptically collected from consenting students and subjected to comprehensive laboratory analysis. Urinalysis was performed to detect markers such as leukocytes, nitrites, and protein. The identified microorganisms were subjected to antibiotic susceptibility testing using the standard disc diffusion method. The results showed that 24% of urine samples tested positive for leukocytes, 17% for nitrites, and 15% for protein, indicating possible UTIs. Bacterial counts were generally higher in female students, within 21–25 age group showing the highest mean TVC. Six distinct bacterial species were isolated, with Staphylococcus aureus (33%) being the most prevalent, followed by Escherichia coli (21%), Pseudomonas spp. (11%), and MRSA (16.7%). MRSA occurrence was higher in females compared to males and also peaked in the 21–25 age group. Antibiotic susceptibility testing revealed that Staphylococcus aureus showed resistance to cloxacillin and oxacillin, while Proteus sp. and Klebsiella sp. were susceptible to ofloxacin and ceftriaxone. The highest MAR index of 0.44 was observed in Staphylococcus aureus, indicating significant multidrug resistance. The findings indicate the presence of multidrugresistant uropathogens in the student population. This shows a potential reservoir for transmission, necessitating improved sanitation in hostels and public health campaigns to raise awareness about antibiotic resistance. Further research should focus on molecular characterization of resistance genes and explore alternative strategies such as targeted antimicrobial therapies and hygiene interventions.

The popularity of the plant- based milk drinks is on the increase as substitutes to the traditional dairy products due to the growing consumer awareness of the health, sustainability and ethical concerns. Although plant-based milk drinks have nutritional ad vantages, there are major challenges in production, storage and distribution and has been associated with higher chances of food-borne disease. Some studies have indicated bacterial contaminants in plant-based milk drinks including soya milk, kunu and coconut milk. This research paper sought to examine the bacterial and fungal contamination profile of plant-based milk drinks during storage. The milk drinks are the plant-based ones which were bought in three Benin City markets and they consist
of the samples of kunu, soya, tiger nut and coconut milk. The enumeration and isolation of bacteria and fungi were done using the pour plate method. Identification was done using the cultural, morphological and biochemical characteristics of the isolates. The heterotrophic bacterial counts had a mean of 1.90+-0.53x105 (soya milk) -82.40+-6.90 x 105 cfu/mL (coconut milk). The total Salmonella-Shigella count was between 1.10+-0.48 x 105 cfu/mL (tiger nut milk) and too numerous to count (coconut milk). The average fungal counts were between 2.40+-0.25 (soya milk) -44.00+-0.00 x 105 cfu/mL (tiger nut milk). The identified bacterial isolates are Bacillus cereus (16.00%), (25.00%), Pseudomonas sp. (8.33%), Klebsiella pneumoniae (25.00%), Bacillus subtilis (16.60%), Staphylococcus sp. (25.00%) and Salmonella sp. (16.60%). Saccharomyces sp. (16.60%), Mucor sp. (8.33%), Penicillium sp. (16.60%) and
Aspergillus flavus (25.00%) were the most common genera of the fungi.