Aim: This study aimed to evaluate the ability of Fish waste and Goat manure to bio-stimulate the degradation process during bioremediation of crude oil-contaminated soil. Study Design: Research was designed to evaluate and compare the strength of the organic nutrients (Goat manure and fish waste)   to stimulate the biodegradation of crude oil contaminated soil within 56 days. Place and Duration of Study: Study was carried out in Rivers State University Farm, Rivers state, Nigeria for 56 days from July to September 2018.  Analyses were carried out weekly (per 7 days interval). Methodology:  Eight (8) experimental set-up were employed, each having 5kg farm soil, all were left fallow for 6 days before contamination with crude oil on the 7th day in the respective percentages. Four of the set-ups were contaminated with 5% Crude oil while the other four were contaminated with 10% Crude oil. The contaminated plots were further allowed for 21 days for proper contamination and exposure to natural environmental factors to mimic a crude oil spill site before the application of bio stimulating agents (fish waste and goat manure). The set-ups of 5% Crude Oil Contaminated Soil (5% COCS) and 10% Crude Oil Contaminated Soil (10% COCS) were then stimulated with nutrient organics; Goat Manure (GM) and Fish Waste (FW) except two setups (one 5% COCS and the other 10% COCS) which were used as controls. The treatments (setups) were as follows: 5% COCS    (control 1), 5% COCS + GM, 5% COCS + FW, 5% COCS + GM + FW and 10% COCS (Control 2), 10% COCS +GM, 10% COCS + FW, 10% COCS + GM + FW. Physiochemical and microbiological status of the soil before and after contamination was evaluated while parameters including Nitrate, Sulphate, Phosphate and Total Petroleum Hydrocarbon (TPH), as well as Microbial analyses, were monitored throughout the experimental period. Bioremediation efficiency was estimated from percentage (%) reduction of Total Petroleum Hydrocarbon (TPH) from day 1 to the residual concentration at day 56 of bio-stimulation setups with the control. The bio-stimulating potentials of goat manure and fish waste were compared using statistical tools. Results: The results revealed decrease in TPH with increasing time. The Amount (mg/kg) and Percentage (%) of Total  Petroleum  Hydrocarbon (TPH) remediated within the period of this study for 5% Crude Oil Contaminated Soil were as follows: 5% COCS-Ctrl 1 (563.52 mg/kg; 8.60%) < 5% COCS + GM (3608.84 mg/kg; 55.11%) < 5% COCS + FW (4156.49 mg/kg; 63.47%)  < 5% COCS + GM + FW (4350.69 mg/kg; 66.44%) while 10% crude oil contaminated soil were: 10% COCS-Ctrl 2 (125.71 mg/kg; 1.21%) < 10% COCS + GM (4422.75 mg/kg; 42.82%) < 10%COCS + FW (5542.16 mg/kg; 53.66%) < 10% COCS + GM + FW (6168.66 mg/kg; 59.72%). This result shows that combination treatment with goat manure and fish wasteis more effective and has more bio-stimulating potentials than the single treatments. With respect to individual bio-stimulating agent, fish waste proves more effective and had a higher bioremediation efficiency than goat manure. The results of colonial counts obtained revealed that the total heterotrophic bacterial and total fungal counts generally increased during the study across the trend. The counts obtained from day 7 to 56 in the respective experimental set ups were as follows: Total Heterotrophic Bacteria  counts increased from 6.32 to 8.20 Log10CFU/g (Control) < 6.32 to 9.05 Log10CFU/g  (COCS+FW) < 6.41 to 9.13 Log10CFU/g (COCS+GM) < 6.32 to 9.58 Log10CFU/g (COCS+FW+GM). Similar progression was observed for total fungi, hydrocarbon utilizing bacteria and hydrocarbon utilizing fungi in all the experimental set ups although irregular differences were observed in the control set ups. Conclusion: The combination of organic nutrient such as goat manure and fish waste as bio-stimulating agents have shown to have higher percentage (%) bioremediation efficiency than when applied singly. It was also observed that the microbial biomass increased with time; moreover the nutrient monitoring analysis revealed a continuous gradual increase of the soil nutrient as bioremediation increases with time. The nutrient inherent in the bio-stimulating agents’ fish waste and goat manure resulted in increased soil nutrient (from day 7 to 56) as bioremediation period increase thereby enhancing soil nutrients at end of experiment. It is therefore recommended that bio-stimulating agents such as fish waste and goat manure should be employed in bioremediation of crude oil-contaminated soil especially due to its soil nutrient enhancement after bioremediation exercise. It’s a very good nutrient amendment option.

Many substances known to have toxic properties are regularly introduced into the environment through human activity. These substances which include hydrocarbons range in degree of toxicity and danger to human health. Frequent oil spills incidents have become a problem to ecological protection efforts. Conventional methods to remove, reduce or mitigate toxic substances introduced into soil via anthropogenic activities suffer setbacks due to the level of risk involved but bioremediation offers an alternative method to detoxify contaminants especially if the soil conditions are amended with organic nutrients or growth enhancing co-substrates. This study was therefore aimed characterizing hydrocarbon utilizing microorganisms associated with crude oil contaminated soils. Soils were obtained from the Rivers State University Agricultural farm contaminated deliberately with crude oil and allowed for 21 days to mimic the natural polluted soil. Sample collection and analyses were carried out according to standard microbiological procedures while characterization of the isolates was done using genomic studies. The results of microbial counts obtained from the soil samples for total heterotrophic bacteria ranged from 2.10 x108 to 2.58 x108 cfu/g, Total heterotrophic fungi had 1.6 x105 to 2.0 x105 cfu/g while the hydrocarbon utilizing bacteria ranged from 8.0 x103 to 5.0 x104 cfu/g and total hydrocarbon utilizing fungi ranged from 9.0 x103 to 7.0 x104 cfu/g in the contaminated soil. Five hydrocarbon utilizing bacterial species were identified as Staphylococcus saprophyticus, Bacillus amyloliquefaciens, Pseudomonas aeruginosa, Comamonas testosteroni and Chryseobacterium cucumeris while five hydrocarbon utilizing fungal species were identified as Penicillium citrinum, Penicillium brocae, Fusarium solani, Kodamaea ohmeri and Lentinus squarrosulus. Bacillus and Penicillium species were predominantly isolated from the soil. This may be due to the ability of the organisms to produce spores, which may shield them from the toxic effects of the hydrocarbons. Since these organisms are able to utilize crude oil as their sole carbon source. Hence, can be used for bioremediation of crude oil polluted environment.

Comparative evaluation of crude oil degradability efficiency of Bacillus amyloliquefaciens and Comamonas testosteroni with nutrient amendment were investigated in Crude oil Contaminated Soil. The bacteria species used in this study were isolated from the soil collected from Rivers state university research farm using standard microbiological methods. Evaluation and monitoring of bioremediation were done for a period of 56 days while analyses were carried at a constant interval of seven (7) days. Seven (7) experimental set-ups were employed using black polythene bag, The bags were perforated to enhance aeration,  each containing 5 kg of agricultural soil and left to fallow for 6 days, on the seventh day each of the experimental set-ups (5kg of soil) except the control (CTRL) were contaminated with crude oil (COCS) giving initial Total Petroleum Hydrocarbon (TPH) value of 10328.03 mg/kg; after which it was allowed for 21 days to ensure even distribution and soil-oil bonding to mimic crude oil spill site before application of augmenting bacteria; Bacillus amyloliquefaciens (BC) and Comamonas testosteroni (CM) and the stimulant; Goat manure (GM). Soil profile before and after contamination were analyzed while parameters like Sulphate, pH, Nitrate and Total Petroleum Hydrocarbon (TPH), as well as microbial analyses such as Total Heterotrophic Bacteria (THB), Total Heterotrophic Fungi (THF), Hydrocarbon Utilizing Bacteria (HUB) and Hydrocarbon Utilizing Fungi (HUF) were monitored and evaluated throughout the experimental period. Bioremediation efficiency was estimated from percentage (%) reduction of Total Petroleum Hydrocarbon (TPH) from day 1 to the residual hydrocarbon at day 56 of bioaugmented/biostimulation set-ups with the control. The microbiological result of the soil before and after contamination revealed that Bacillus sp had the highest percentage for bacterial isolates while Mucor sp. had the highest percentage for fungal isolates in both uncontaminated and contaminated soil. Colonial count of uncontaminated soil ranged from 5 x104 (HUB) <7 x 104 (HUF) <1.6 x 105 (THF) to 2.58 x 108 (THB) while contaminated soil colonial count ranged from 8 x 104 (HUB) < 9 x 104 (HUF) <2.0 x105 (THF) to 2.10x108 (THB). Microbial evaluation of the bioremediation set-ups showed increased colonial values with increase in time but slightly decreased on the last day. Results of total petroleum hydrocarbon revealed the actual amount of hydrocarbon reduction after the experiment and its percentage hydrocarbon remediated from the initial concentration in the various treatment setups  in the following  decreasing order;(CTRL) 125.71 mg/kg; 1.21% < (COCS + BC) 1855.74 mg/kg; 17.96% < (COCS + CM) 2261.01 mg/kg; 21.89% < (COCS + CM+ BC) 3321.23 mg/kg; 32.15% < (COCS + GM + BC) 4983.81 mg/kg; 48.25 < (COCS + GM + CM) 7313.47 mg/kg; 70.81%. Conclusively, the results obtained indicate that Comamonas testosteroni with nutrient amendment had the more degradability efficiency compared to Bacillus amyloliquefaciens. It is therefore recommended that bioremediation crude oil polluted soil using bioaugmentation technique should be amended with organic nutrient to enhance efficiency.

Phenol in industrial effluent is a major under-reported pollutant of concern to the aquatic ecosystem. In the current study, the effluent was obtained from Eleme Petrochemical Limited, Rivers State Nigeria. Baseline analyses were conducted to ascertain physico-chemical and microbiological parameters. Exogenous bacterial species were isolated from crude oil polluted in Ogoniland. The inoculum was standardized using the MacFarland approach. About 1% inoculum was seeded into the 100 mL effluent for the Pseudomonas aeruginosa, Micrococcus sp, Bacillus tequilensis and consortia. The setup was monitored using Gas Chromatography-Mass spectrophotometry while the acute toxicity was calculated using the Probit method. The acute toxicity of the set-up seeded with Pseudomonas aeruginosa was 718.8 mg/L while the consortia had 941.2 mg/L. The phenol residues were reduced by 100% while the 2-nitrophenol was reduced from 5.13 µg/L to 0.82 µg/L on the 10th day of the study. The remarkable reduction of the phenol residues with the use of microbial cultures goes to show the efficiency of locally sourced feedstock as tools for the degradation of pollutants. There is an urgent need for academia to develop robust microbial bio-mining and culture collection centers for futuristic and commercial use.

Aim: This study reports the production of cellulase by Bacillus licheniformis VVA21 isolated from hydrocarbon contaminated Kegbara-Dere mangrove in Ogoniland, Nigeria. Methodology: Baseline physicochemical characteristics of the hydrocarbon contaminated soil were established. Twenty-two bacterial isolates were screened for cellulolytic activity on carboxymethyl cellulose (CMC) agar using the spread plate technique. The isolate with the highest zone of clearance was selected and assayed further. Crude cellulase was extracted and partial purification achieved by ammonium sulphate precipitation, followed by dialysis, and final purification Original Research Article