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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.

The effectiveness of agricultural wastes as bioremediation materials is gaining research attention as a better option in mitigating the issue of crude oil effects in soil environment. In the present study, the growth performance of Telfairia occidentalis and Arachis hypogaea linn in crude oil polluted soil amended with plantain peels (PP) and cocoa pod husks (CPH) were investigated. Eight kilograms (8 kg) each of dried soil samples were collected and weighed into 60 polythene bags. The polythene bags except the pristine control were polluted with 80 ml of crude oil and allowed for 14 days of soil acclimatization. The treatments comprising of CPH and PP were amended after 14 days, using the following concentrations: 0, 100, 150 and 200 g and allowed to acclimatize for 60 days. T. occidentalis and A. hypogaea linn were cultivated immediately after treatment regimen. The pH of the amended and un-amended soil samples were observed to be at a range recommended for effective bioremediation of hydrocarbon polluted soil. The organic carbon content of the CPH amended soils were significantly reduced as compared to the PP amended soil. The phosphorus, nitrogen, potassium and other essential soil parameters evaluated were significantly high (P<0.05) in CPH amended soil than the PP amended soil. Crops grown in the rehabilitated soils possess a high adaptability in CPH amended soil than the PP amended soil. The amendments most preferably cocoa pod husks which tend to be more effective in the reduction of hydrocarbon content of the soil should be utilized in the enhancement of microbial degradation of crude oil product in soils.

Background One of the main challenges of wound healing is infection with multi-drug resistant (MDR) bacteria such as Staphylococcus aureus. The spectrum of antibiotics used to treat them is declining; thus, there is a need for alternatives. Our study was designed to evaluate the antimicrobial properties of honey, its pharmacokinetics (ADMET) properties and in-silico analysis of its bioactive compounds against dihydropteroate synthase of S. aureus using trimethoprim as control. Methods Standard protocols were employed in collection and preparation of samples, generation of canonical strings, and conduction of microbiological analyses. Bioactive compounds’ ADMET properties were evaluated using the SWISSADME and the MCULE toxicity checker tools. The MCULE one-click docking tool was used in carrying out the dockings. Results The gas chromatography-mass spectrophotometry revealed twenty (20) bioactive compounds and was dominated by sugars (> 60%). We isolated a total of 47 S. aureus isolates from the wound samples. At lower concentrations, resistance to trimethoprim (95.74 to 100.00%) was higher than honey (70.21 to 96.36%). Only seven (7) isolates meet Lipinski’s rule of five and ADMET properties. The docking scores of the bioactive compounds ranged from -3.3 to -4.6 while that of trimethoprim was -6.1, indicating better binding or interaction with the dihydropteroate synthase. The bioactive compounds were not substrates to P450 cytochrome enzymes (CYP1A2, CYP2CI9 and CYP2D6) and p-glycoprotein, indicating better gastrointestinal tract (GIT) absorption. Conclusion The favourable docking properties shown by the bioactive compounds suggest they could be lead compounds for newer antimetabolites for management of MDR S. aureus.

This work was carried out in collaboration between all authors. Author IUB designed the study, wrote the protocol and wrote the first draft of the manuscript. Author LO managed the literature searches, analyses of the study and managed the experimental process while author IEA identified the greenhouse gases encountered in the studied dumpsites. All authors read and approved the final manuscript.