In the present study, an agricultural soil artificially amended with different concentrations of palm oil mill effluent was analysed to determine its impact on the soil microflora and other properties such as pH, organic matter, electrical conductivity, and mineral elements. In the polluted soils, the total heterotrophic bacteria, total heterotrophic fungi and total heterotrophic actinomycetes decreased significantly (p≤0.5) with increase in the concentration of the pollutant. The total heterotrophic bacteria and total heterotrophic fungi showed significant reduction (p≤0.5) with increase in the duration of the pollution while total heterotrophic actinomycetes showed no significance difference (p≥0.5) over the duration of pollution. Suspected bacterial isolates from the polluted soils were

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This study was designed to assess the total heterotrophic and hydrocarbon oxidizing microbial diversity, determine the physicochemical parameters of oil contaminated soil and evaluate the potentials of microorganisms isolated to utilize spent oil. Three mechanic workshops within Calabar South axis of Cross River State Nigeria were selected and three soil samples were collected from each site. The total heterotrophic bacteria were enumerated on nutrient agar and the hydrocarbon utilizing bacteria on minimal salt medium using the vapor phase method after employing the ten-fold dilutions from 1:10 to 1:100000. The total heterotrophic mean count ranged from 1.28×10 4 to 3.58×10 4 cfu/g while mean count of hydrocarbon utilizing bacteria varied from 1.94×10 4 to 7.34×10 4 cfu/g. Physicochemical parameters of samples were determined. Such parameters included pH, electrical conductivity and compounds such as nitrate, nitrite, phosphate, calcium, magnesium and potassium. The bacterial isolates evaluated belonged to the genera of Bacillus, Klebsiella, Proteus, Pseudomonas, Enterococcus, Flavobacterium and Micrococcus spp. Klebsiella spp. emerged as the most prevalent heterotrophic bacteria with 29.41% while Bacillus spp, and Enterococcus spp. were Original Research Article JAMB, 4(4): 1-9, 2017; Article no.JAMB.34847 2 the least prevalent with 11.77%. Among the hydrocarbon utilizing bacteria, Pseudomonas flourescens was the most prevalent species with 53.85% while Micrococcus spp. was the least with 15.39%. Amongst the 3 different sites studied, the mechanic workshop at Goldie Street had the highest mean value for both heterotrophic and hydrocarbon utilizing bacteria ranging from 2.52x10 4 to 3.58 x10 4 cfu/g for total heterotrophs and 3.27x10 4 to 7.34x10 4 cfu/g for hydrocarbon utilizers. The findings reveal that there is a high prevalence of certain populations of active indigenous hydrocarbon oxidizing bacteria which can be monitored and enhanced to bring about bioremediation in the study area.

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Tap water samples collected from different halls in Malabor hostel were analyzed for total heterotrophic bacteria count, total and faecal coliform counts using direct plating and membrane filtration methods. Total heterotrophic bacterial counts ranged from 3 to 80 cfu/ml, corresponding to the total heterotrophic bacterial counts obtained from Hall 4 and Hall 9 samples respectively. Total coliform counts ranged from 28 cfu/ml to 126 cfu/ml, corresponding to the total coliform counts obtained from Hall4 and Hall9, respectively. No faecal coliform was detected at 35-37°C in all samples even after 72 hours of incubation. Bacterial isolates identified include: Listeria monocytogenes, Erwinia stewartii, Legionella pneumophilia, Carnobacterium gallinarum, Staphylococcus caseolyticus, Enterobacter dissolves, Pseudomonas mallei, Klebsiella pneumonia, Aeromonas media and Lactobacillus sp. Lactobacillus sp. had the highest percentage of occurrence (23%). The physicochemical and heavy metal quality of samples were compared with WHO and SON standards for drinking-water, and results showed that samples were too acidic and contained an unhealthy amount of Aluminum ion (Al 3+).