The diversity of fungi in fifteen public hand-pump borehole water in Onueke, Ezza Local Government Area of Ebonyi State, Nigeria was studied during the dry and wet seasons using standard analytical procedures. The total moulds and yeasts counts were 2-8cfu/ml and 1-5cfu/ml respectively during the dry season and 3-12cfu/ml and 1-4cfu/ml respectively during the wet season. More moulds were isolated from the samples during the wet than the dry season while more yeasts were isolated during the dry than the wet season. The fungi were characterized and identified on the basis of their colonial, microscopic, biochemical and molecular characteristics as Candida albicans, Microsporum canis, Aspergillus fumigatus, Geotrichum candidum, Basidiobolus ranarum, Microsporum audouinii, Fonsecaea pedrosoi and Trichosporon cutaneum. More of the boreholes contained Candida albicans than the other isolates during both seasons. Candida albicans occurred most frequently in the water samples during both seasons while Fonsecaea pedrosoi had the lowest frequency of occurrence in the water samples during both seasons. All the isolates were resistant to Griseofulvin while they exhibited varying degree of resistance and sensitivity to the other antifungal agents used. This study indicated that the borehole water samples examined did not comply with the standard established by regulatory bodies for potable water and therefore must be adequately treated before drinking and use for domestic purposes as these fungi have been reported to cause diseases of humans and animals. Boiling, chlorination, sand filtration and exposure to ultraviolet radiation are recommended.

The biodeterioration potentials of microorganisms isolated from pig manure was studied using standard methods. The heterotrophic microorganisms isolated from the manure were Escherichia coli, Micrococcus luteus, Enterococcus faecalis, Staphylococcus aureus, Proteus vulgaris, Shigella flexneri, Serratia marcescens, Pseudomonas aeruginosa, Aspergillus niger, Cladosporium resinae, Penicillium expansum, Trichoderma herbarum and Candida tropicalis while all the organisms except Escherichia coli and Staphylococcus aureus were the hydrocarbon-utilizing isolates. The most active degraders were Pseudomonas aeruginosa, Micrococcus luteus, Aspergillus niger, Cladosporium resinae and the bacterial and fungal consortia that produced the highest turbidity and clarity indicating hydrocarbon utilization. The growth profile of Micrococcus luteus, Pseudomonas aeruginosa, Aspergillus niger and Cladosporium resinae as well as the fungal and bacterial consortia during 35 days of growth in mineral salts-oil medium showed that there was a decrease in the pH and an increase in the viable count of the medium. The highest percentage degradation of the crude oil was by the bacterial consortium (62.0%). This work showed that Pig manure which is generally regarded as a waste product harbours diverse bacteria and fungi which will be useful in remediating oil-polluted environments when applied singly and as a consortia.

The primary function of aviation fuel is to provide propulsive energy to the aircraft. Microorganisms may contribute to aging instability in the fuel, induce corrosion of the storage tanks and pipeworks, form mats which can block filters and pipelines and increase wear in fuel pumps eventually leading to engine failure, therefore, in this study, the microbial contaminants in the commercial aviation fuel obtained from Benin City Airport, Nigeria were isolated, characterized, identified and their hydrocarbon-utilizing potentials determined using standard methods. The microbial contaminants were Micrococcus luteus, Serratia marcescens, Pseudomonas aeruginosa, Bacillus subtilis, Citrobacter freundii, Klebsiella aerogenes, Acinetobacter calcoaceticus, Fusarium oxysporum, Penicillium italicum, Rhizopus stolonifer, Aspergillus fumigatus and Candida tropicalis. Serratia marcescens had the highest percentage distribution (16%) in the fuel. Serratia marcescens, Pseudomonas aeruginosa, Acinetobacter calcoaceticus, Rhizopus stolonifer and Aspergillus fumigatus were the best utilizers of the fuel among the organisms isolated. There was a drop in the initial pH of the mineral salts oil medium inoculated with the isolates indicating hydrocarbon utilization. The result of this work showed that the fuel examined was contaminated with bacteria and fungi, therefore the incorporation of effective biocides, frequent inspection and drainage of water from fuel tanks and pipeworks are recommended.

Bacteriological quality assessment of some hand-dug shallow water wells in Awka metropolis was carried out during the dry and wet seasons to determine their potability. The total bacterial, total coliform, faecal coliform and Vibrio chloreae counts were determined using standard laboratory methods. The total bacterial counts during the dry season ranged from 100 to 300 cfu/100ml; total coliform counts, 42-126 cfu/100ml; faecal coliform counts, 10-26 cfu/100ml and Vibrio cholerae counts, 2-10cfu/100ml. During the wet season, the total bacterial counts ranged from 148 to 450 cfu/100ml; total coliform counts, 77-240 cfu/100ml; faecal coliform counts, 12-30 cfu/100ml and Vibrio cholerae counts, 6-13 cfu/100ml. The bacteria isolated during the dry season were Salmonella typhi (7.44%), Proteus vulgaris (18.08%), Pseudomonas aeruginosa (27.55%), Enterobacter aerogenes (35.71%), Vibrio cholerae (2.85%) and Escherichia coli (8.37%). During the wet season, the bacterial isolates were Salmonella typhi (6.14%), Proteus vulgaris (14.56%), Pseudomonas aeruginosa (21.69%), Enterobacter aerogenes (29.70%), Vibrio cholerae (3.66%), Escherichia coli (8.23%) and Klebsiella pneumoniae (16.03%). All the water wells studied were of poor bacteriological quality. Appropriate water purification methods should therefore be developed for such wells to avert a public health hazard.

Ogbaru Communities are usually submerged by intense flood during the rainy season, but such flood recedes during the dry season. This natural occurrence makes the quality of the borehole water in the area questionable. The total bacterial, total coliform, faecal coliform and Vibrio cholerae counts of samples from fifteen boreholes in the communities were determined during both seasons using standard analytical methods. The values were 100-270 cfu/100ml;10-42cfu/100ml;0-28 cfu/100ml and 0-13cfu/100ml for total bacterial, total coliform, faecal coliform and Vibrio cholerae counts respectively during the dry season and 130-450 cfu/100ml; 25-86 cfu/100ml; 0-75 cfu/100ml and 0-18 cfu/100ml for the total bacterial, total coliform, faecal coliform and Vibrio cholerae counts respectively during the rainy season. Salmonella typhi (53.3%), Enterobacter aerogenes (53.3%), Pseudomonas aeruginosa (46.7%), Proteus vulgaris (46.7%), klebsiella variicola (26.7%), Escherichia coli (26.7%), Staphylococcus aureus (13.3%) and Vibrio cholerae (33.3%) were isolated during the dry season while S. typhi (60.0%), E. aerogenes (60.0%), P. aeruginosa (53.3%), P. vulgaris (46.7%). K. variicola (33.3%), E. coli (26.7%), S. aureus (13.3%), V. cholerae (46.7%) and Providencia sneebia (6.7%) were recovered during the rainy season. S. typhi occurred most frequently during both seasons. Total bacterial, total coliform and Vibrio cholerae counts were significant at 5% significance level using t-distribution. The boreholes analysed were polluted by bacteria and need adequate treatment such as sand filtration, chlorination and boiling before drinking to avert a public health hazard.