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This study was aimed at determining the effect of varying concentration of crude oil pollution on the macronutrients in the soil. Various macro-nutrients (such as soil ammonium concentration, soil nitrate concentration, and available phosphorus), oxidizable organic carbon, and total petroleum hydrocarbon were determined. The result revealed that as the time increases, the oxidizable carbon, which is also a function of the organic matter decreases, which is as a result of the conversion of carbon to carbon (IV) oxide during cellular metabolism. This decrease showed that there was an increase in the activity of that leads to the breakdown of the carbon components in the soil. The soil phosphate concentration determination did not show any pattern in their increase or decrease, which shows that increase in crude oil concentration, did not significantly affect the phosphate concentration in the soil. The soil ammonium concentration increased from 24 th hour to 168 th hour but decreased before the end of the experiment. This increase could be attributed to ability of the Azotobacter vinelandii to fixed nitrogen as an innate responsibility, while Pseudomonas sp. which is known to contain nitrogen fixing genes. The result also showed that there is a constant increase in soil nitrate concentration which is affected as the concentration of the pollutant (crude oil) increases. This study has shown that the consortium of these organisms can be used as a bio-fertilizer as well as in bioremediation.

This investigation was carried out in four different locations mapped out along the river bank. Twelve water samples were collected and six different fresh fish species that are frequently consumed were caught. They include: African red snapper (Lutjanus agennes), Yellow tail (Seriola lalandi), Barracuda (Sphyraena barracuda), Atlantic Croker (Micropogonias undulates), Catfish (Clarias gariepinus) and Tilapia (Oreochromis niloticus). Samples were subjected to screening using gas chromatography and flame ionization detector instrument. Results revealed presence of total petroleum hydrocarbon (TPH) contaminant in all the fish samples and varies with species significantly at p >0.05.The bioaccumulation factor varies in fish species, where the Yellow tail have higher bioaccumulation factor 969,369061, followed by Barracuda 695,067209, Tilapia 667,101072, Catfish 466,368366, African red Sniper 439,616275 and Crocker fish 104,2956024 respectively. This investigation reveal considerably the extent of bioaccumulation of TPH contaminants in aquatic animal models and making unsafe for consumption as some fishes bio-accumulate nonane beyond permissible limit.

Various concentrations of lead (II) tetraoxosulphate (VI) were prepared by dissolving 1 g, 1.5 g, 2 g and 3 g of the salt in deionized water and making up to volume to100ml. Soil samples were prepared and allowed to equilibrate with the different concentrations of the salt samples. After equilibration, earthworm species which had been acclimatized to the in-situ environment were introduced the equilibrated soil samples. The earthworms were allowed to stay between 3-5 days in the soil samples. They were harvested and the lead (II) tetraoxosulphate (VI) content of the earthworm samples. The result showed that the earthworms possessed the ability to bioaccumulate the salt samples and the statistical analysis showed increase in bioaccumulation with increase in the salt content.

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A high potential iron-Sulphur protein (HiPIP) Iron Oxidase (E.C 1.9.3.1) was isolated from Acidithiobacillus species obtained from Ironstones of Agbaja Mines of Kogi State, Nigeria. The aim was to study the biochemical characteristics of the enzyme so as to find out its catalytic contribution to the rate of bioleaching of the studied organism. A simple partial purification profile consisting of cell homogenization, ammonium sulphate precipitation, Ion-exchange using Carboxyl methyl cellulose, and sephadex G-200 chromatography were used. The biochemical and kinetic properties of the enzyme were thereafter studied. The Iron oxidase had its highest specific activity of 14.70 μmole/ml/mg of protein and yield of 89% with a purification fold of 1.43 after size exclusion chromatography. Optimum temperature and pH were found to be 50°C and 6.0 with Km and Vmax of 0.03mM and 12 mMole/min respectively. Inhibition studies conducted shows that tween 20 and SDS had the maximum rates. Other characteristics of the enzyme show that it might be a novel member of HiPIP coming from the isolated Acidithiobacillus of Agbaja Iron ore Mines.

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