scholarly journals Bioremediation Potential of Pseudomonas aeruginosa KX828570 on Crude Oil Spill Polluted Marshland and Terrestrial Soil Treated with Oil Spill Dispersant

2019 ◽  
pp. 1-15
Author(s):  
Renner Renner Nrior ◽  
Augusta Ogechi Inweregbu
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Moisture Content ◽  
Crude Oil ◽  
Oil Spill ◽  
Heterotrophic Bacteria ◽  
Soil Samples ◽  
Total Hydrocarbon ◽  
Hydrocarbon Content ◽  
Rivers State ◽  
Total Hydrocarbon Content

Aim: To investigate bioremediation potentiality of Pseudomonas aeruginosa KX828570 on crude oil Polluted Marshland and Terrestrial Soil treated with oil spill dispersant Study Design: The study employs experimental design, statistical analysis of data and interpretation. Place and Duration of the Study: Soil samples were collected from K-Dere, Gokana L.G.A, and were transported to the Microbiology Laboratory of Rivers State University, Port Harcourt, Nigeria for analyses while Oil spill dispersant (OSD/LT and OSD/Seacare) were from Barker and Hughes Nig Ltd (formally mil park Nigeria limited), all in Rivers state, Nigeria. This investigation study lasted for 28 days and sampling was done every 7day period. Methodology: Eight experimental set up were carried out using Pseudomonas aeruginosa KX828570 as the bio-augmenting organism in terrestrial and marshland soil contaminated with two Oil spill dispersant (OSD/LT and OSD/Seacare) separately. Controls for the two soil types were made without organism and treatment. Its bioremediation potential on the pollutants and two types of soil were monitored for 28 days. The setup was tilled twice a week to provide moisture and more oxygen for the organisms to thrive. Analysis of pH, Temperature, Moisture content, Total Hydrocarbon Content, Total Heterotrophic Bacteria, Dispersant Utilizing Bacteria was carried out at weekly intervals. Results: The pH of both soils ranged from 5.75 to 7.37; temperature from 270C to 340C; moisture content 03 to 0.6 across the soil samples. Total Hydrocarbon Content (THC) showed a steady decline from day 1 – 28. The percentage (%) bioremediation rates of polluted soils were as follows: Terrestrial soil+OSD/Seacare+Pseudomonas aeruginosa KX828570 69.4% > Terrestrial soil+OSD/LT+ Pseudomonas aeruginosa KX828570 65.9% > Marshland soil+OSD/Seacare+ Pseudomonas aeruginosa KX828570 52.6% > Marshland soil+OSD/Seacare+ Pseudomonas aeruginosa KX828570 47.6%. Dispersant utilizing bacterial count in marshland and terrestrial soil ranged from 6.013 to 7.338 log10Cfu/g and 6.045 to 7.301 log10Cfu/g respectively from Day 1 to 28. Conclusion:  From the investigation, it revealed that Oil spill dispersants are more degradable in terrestrial soil than marshland soil. OSD/Seacare is more biodegradable than OSD/LT in both terrestrial and marshland soil augmented with Pseudomonas aeruginosa KX828570. Thus, Pseudomonas aeruginosa KX828570 have been found to be a potential bioremediation agent in oil spill dispersant polluted marshland and terrestrial soil.

scholarly journals Impacts of Artisanal Crude Oil Refining Activities on Soil Microorganisms

2019 ◽  
pp. 1-9
Author(s):  
Douglas, Salome Ibietela ◽  
Cornelius, Blessing Tamunonegiyeofori
Keyword(s):  
Crude Oil ◽  
Soil Microorganisms ◽  
Microbial Population ◽  
Soil Samples ◽  
Oil Refining ◽  
Bacterial Counts ◽  
Total Hydrocarbon ◽  
Hydrocarbon Content ◽  
Microbiological Methods ◽  
Total Hydrocarbon Content

Aim: To evaluate the effect of illegal crude oil refining activities on soil microorganisms using standard microbiological methods. Study Design: This study employs laboratory experimental design, statistical analysis of the data and interpretation. Place and Duration of Study:  Soil samples were taken once a month for three months (May- July, 2018) from Ke in Degema Local Government Area of Rivers State, Nigeria, where illegal crude oil refining activities are ongoing. Methodology: Using standard microbiological methods, total culturable heterotrophic bacterial counts, total fungal counts, Hydrocarbon utilizing bacterial and fungal counts were analysed to evaluate the effect of the activities. Total hydrocarbon content of the soil samples was also analysed. Results: The populations of the total heterotrophic bacterial, fungal and hydrocarbon utilizing bacterial (HUB) and fungal (HUF) counts of the contaminated soil were enumerated. The mean total heterotrophic bacterial counts in Station 1 around the pot ranged from 2.5 x 105 to 1.8 x 106cfu/g, fungal counts ranged from 2.1 x 103 to 4.4 x 104cfu/g, HUB (HUB) counts ranged from 4.2 x 104 to 6.4 x 105cfu/g and hydrocarbon utilizing fungal (HUF) counts ranged from 1.5 x 103 to 4.0 x 103cfu/g. The results of soil samples taken 20m away from the Pot location ranged from 7.0 x 105 to 8.2 x 106cfu/g for total heterotrophic bacterial counts, fungal counts ranged from 2.3 x 103 to 1.5 x 104cfu/g, HUB ranged from 4.7 x 104 to 5.7 x 105cfu/g and HUF ranged from 2.0 x 103 to 3.5 x 103cfu/g. Also, the results of total heterotrophic bacterial counts for Station 2 ranged from; 4.3 x 105 to 3.3 x 106cfu/g, fungi 2.0 x 103 to 3.3 x 104cfu/g, HUB ranged from 3.8 X 104 to 5.4 x 104cfu/g  and HUF 1.6 x 103 to 3.5 x 103cfu/g, while 20m away from the Pot total heterotrophic bacteria ranged from 1.3 x 107 to 6.5 x 107cfu/g, fungi 5.8 x 103 to 1.4 x 105cfu/g, HUB 5.4 x 104 to 1.1x 105cfu/g and HUF 3.1 x 103 to 4.7 x 104cfu/g. While the control samples taken from inside the community where no such activity is on, ranged from 2.6 x 107 to 7.9 x 107cfu/g for total heterotrophic bacterial counts, total heterotrophic fungal counts ranged from 2.8 x 104 to 5.3 x 104cfu/g, HUB 2.0 x 102 to 3.1 x 102cfu/g and HUF 2.0 x 101 to 2.3 x 101cfu/g. twelve bacterial genera were identified and eight fungal genera: Bacillus, Alcaligenes, Flavobacterium, Acinetobacter, Pseudomonas, Micrococcus, Proteus, Serratia, Enterobacter, Streptococcus, Escherichia, Staphylococcus, Penicillum, Aspergillus, Fusarium, Mucor, Rhizopus, Geotrichum, Candida, and Cladosporium. Total hydrocarbon content ranged from 106 to 281mg/kg across the locations.  When compared with the control, it was observed that the microbial population and diversity were adversely affected. These variations observed in the microbial population are indicative of the effect of the illegal refinery on the soil microorganisms. Conclusion: The results of this study indicates that the continuous contamination of the soil environment by the activities of illegal crude oil refining, lead to a decrease in microbial population and diversity. This may result in devastating ecological damage, adversely affecting the ecological balance which may affect food chain and in turn animals and humans.

Baseline Studies and Risk Analyses in the Baltic Sea

1991 ◽  
Vol 1991 (1) ◽  
pp. 81-86
Author(s):  
Klavs Bender ◽  
Preben Østfeldt ◽  
Hanne Bach
Keyword(s):  
Baltic Sea ◽  
Oil Spill ◽  
Oil And Gas ◽  
Source Rocks ◽  
The Baltic Sea ◽  
Oil Companies ◽  
Total Hydrocarbon ◽  
Hydrocarbon Content ◽  
The Baltic ◽  
Total Hydrocarbon Content

ABSTRACT In 1986 an oil and gas concession in the Baltic Sea was granted by the Danish Ministry of Energy to a group of oil companies, with Norsk Hydro as operator. A paper describing the goals achieved midway through the program was presented at the 1989 Oil Spill Conference in San Antonio, Texas. This paper presents the final results of the program. The chemical baseline study has shown that the only parameter that exhibits a marked variation is the total hydrocarbon content, where values are seven to eight times higher in the 1989 samples than in the 1987 and 1988 samples. It is suspected that the reason is seasonal variation, since the 1989 samples were collected in June, while the 1987 and 1988 samples were collected in September. Even though the total hydrocarbon content varies significantly between some of the sample suites, only biomarkers related to recent organic material or immature petroleum source rocks are present in the samples. Petrogenic hydrocarbons related to spilled crude oil or exploration activities were not found in the area. The spreading and weathering calculations revealed the zones along the coast where an oil spill was most likely to occur. The transport time for an oil spill to reach the coast was also calculated by the model. In combination with mapping of sensitive resources, the results from the model test runs were used in risk assessments. The information gained in this study was used in the oil spill contingency plan.

scholarly journals Elephant Grass (Pennisetum Purpureum) Mediated Phytoremediation of Crude Oil-Contaminated Soil

2019 ◽  
Vol 3 (1) ◽  
pp. 105-111 ◽  
Author(s):  
L. O. Bobor ◽  
B. E. Omosefe
Keyword(s):  
Crude Oil ◽  
Contaminated Soils ◽  
Control Sample ◽  
Bacterial Count ◽  
Pennisetum Purpureum ◽  
Elephant Grass ◽  
Total Hydrocarbon ◽  
Hydrocarbon Content ◽  
And Control ◽  
Total Hydrocarbon Content

Phytoremediation is an economic and environmentally friendly method for the remediation of hazardous crude oil contaminated soils. In this study, phytoremediation of crude oil contaminated soils by elephant grass (pennisetum purpureum) was investigated over a 40-day period. Grass clumps were harvested and transplanted into plastic buckets filled with 1kg of soil contaminated with 30 ml and 40 ml of crude oil and an uncontaminated control sample. An additional control sample was contaminated with 30 ml of crude oil with no elephant grass. The samples were analyzed periodically for changes in pH, total hydrocarbon content, total viable bacterial count, and total fungal count. The pH of the soil samples generally ranged from 5.26 to 7.85. After 40 days of treatment, the total hydrocarbon content decreased from 320 mg/kg to 38 mg/kg and from 590 mg/kg to 46 mg/kg in samples contaminated with 30 ml and 40 ml of crude oil respectively. Plant growth was uninhibited in contaminated and control samples as the heights increased by 34.5-42.8 cm. The results of the study further demonstrate the phytoremediation capabilities and tolerance of elephant grass in crude-oil contaminated microcosms.

scholarly journals Microbial studies of biosurfactant producing bacteria from crude oil contaminated soil

2021 ◽  
Vol 25 (9) ◽  
pp. 1729-1735
Author(s):  
K.I. Ogru ◽  
P.G. Olannye
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Bacillus Subtilis ◽  
Crude Oil ◽  
Contaminated Soil ◽  
Heterotrophic Bacteria ◽  
Metal Removal ◽  
Soil Samples ◽  
Optimum Growth ◽  
The Mean ◽  
Hydrocarbon Utilizing Bacteria

Soils contaminated with crude oil collected from three sites in Delta State were analyzed using serial dilution and pour plate methods. The physicochemical characteristics of the soil were determined using standard methods. The mean heterotrophic bacteria count and the mean hydrocarbon utilizing bacteria count were also determined. Blood haemolysis, foaming activity, oil spreading techniques and emulsification assay was used to screen the microorganisms for biosurfactant production. The biosurfactant producing bacteria were selected and their effect on metal removal and growth kinetics was also determined. The pH of the contaminated soil samples ranged 4.82 to 5.62. The mineral elements such as potassium (k+) and sodium (Na+) ranged from 0.20 to 0.80 Meq/100g and 0.07 to 0.81 Meq/100g respectively. The heavy metal content such as zinc (Zn2+) and lead (Pb2+) ranged from 10.13 to 19.24 mg/kg and 19.24 to 49.63 mg/kg respectively. Organic carbon and THC ranged from 5.44 to 6.87 % and 2720.00 to 3110.00 mg/kg respectively. The mean heterotrophic bacteria and hydrocarbon utilizing bacteria ranges from 1.4 ± 0.4 x 106 to 1.6 ± 0.7 x 106 and 1.0 ± 0.2 x 106 to 1.2 ± 0.4 × 106 respectively in the soil samples. Bacteria isolated and identified from the three sites include Corynebacterium spp., Bacillus subtilis., Pseudomonas aeruginosa, Micrococcus varians, Streptococcus spp., Klebsiella spp. and Enterobacter spp. with Bacillus subtilis and Pseudomonas aeruginosa having the highest prevalence and among these isolates only Corynebacterium spp., Bacillus subtilis., Pseudomonas aeruginosa and Micrococcus varians showed positive result for the production of biosurfactant. Bacillus subtilis had the highest metal removal capacity of 29.44% of 100 ppm of lead. Corynebacterium spp. and Bacillus subtilis had an optimum growth at pH 8 and 7 respectively while Pseudomonas aeruginosa and Micrococcus varians has an optimum growth at pH.

scholarly journals Physico-chemical Alterations and Hydrocarbon Characteristics of Kom-Kom Oil Spill Soils

2019 ◽  
pp. 1-8
Author(s):  
I. M. Onyejekwe ◽  
L. C. Osuji ◽  
E. O. Nwaichi
Keyword(s):  
Heavy Metals ◽  
Crude Oil ◽  
Oil Spill ◽  
Chemical Properties ◽  
Well Being ◽  
Good Health ◽  
Control Area ◽  
Hydrocarbon Content ◽  
Physico Chemical ◽  
Rivers State

Aims: The aim of this study is to find the alterations that occurred in the physico-chemical properties and the hydrocarbon content on the crude oil impacted soil in Kom-Kom, Oyigbo, Rivers State Niger Delta, Nigeria. Study Design: The objectives included to evaluate the physico-chemical parameters of the spilled soil, determine the hydrocarbon content and that of some selected heavy metals. This will help create a baseline data on the environmental status of the area. Place and Duration of Study: This study was carried out after an oil spill occurred in Feburary, 2018 at Kom-Kom, Oyigbo, Rivers State, Nigeria. Methodology: The soil samples were obtained randomly at 30cm depth using soil auger from three plots: PA and PB being the plots around the oil spill impacted area and PC being the control area which is about 200m away. Laboratory analyses were carried out on the Physicochemical Parameters (pH, Electric Conductivity, Potassium (K), Phosphate (P), Nitrate (N)); Organics (Total Hydrocarbon Content (THC), Total Petroleum Hydrocarbon (TPH), Polycyclic Aromatic Hydrocarbon (PAH) and Total Organic Carbon (TOC)) and Heavy Metals (Iron (PB), Zinc (Zn), Lead (Pb), Chromium (Cr), Vanadium (V)). The data were analysed using descriptive statistics and One-Way ANOVA. Results: pH, K and P values were all significantly different from their respective control values (p ≤0.05). All organic parameters were also significantly different from the control values (p ≤0.05). For heavy metals, only Cr and V values were significantly different in all study sites (p ≤0.05). This study shows that crude oil spill alters the physicochemical attributes of the soil and could significantly affect soil fertility as the people of Kom-Kom are mostly farmers and traders. Conclusion: With these levels of alteration, this study will serve as a resourceful data source for soil studies in Kom Kom. In order to achieve the third sustainable development goal (SDG) which is to have good health and well-being of people, we recommend immediate and proper clean up using bioremediation approaches as a cheap, eco-friendly and an environmentally sustainable process.

scholarly journals Characterization of Indigenous Bacterial Communities in Crude-Oil Impacted Sites at Obagi Town, Onelga, Rivers State, Nigeria

Fine Focus ◽  
2016 ◽  
Vol 2 (1) ◽  
pp. 7-14
Author(s):  
Chioma Blaise Chikere ◽  
Chinyere Augusta Ajuzieogu ◽  
Michael Chukwugoziem Miller
Keyword(s):  
Crude Oil ◽  
Heterotrophic Bacteria ◽  
Bacterial Species ◽  
Polluted Soil ◽  
Soil Samples ◽  
Isolation And Characterization ◽  
Significant Difference ◽  
Rivers State ◽  
Hydrocarbon Utilizing Bacteria

Hydrocarbon utilizers are expected to be indigenous in crude-oil polluted environments. The isolation and characterization of hydrocarbon utilizers is often a key strategy in bioremediation of hydrocarbon-polluted environments. In this study, crude-oil polluted soil samples from Obagi town, Onelga, Rivers state were enumerated and characterized for putative hydrocarbon utilizing bacterial populations. Biochemical characterization identified five bacterial species representative of five genera: Bacillus, Pseudomonas, Acinetobacter, Micrococcus and Staphylococcus. Amongst the genera of bacteria isolated, Bacillus had the highest frequency of occurrence (40%). The mean count of total heterotrophic bacteria was 1.7 X 107 cfu/g, while hydrocarbon utilizing bacteria (HUB) count mean density was 1.0 X 107 cfu/g for the three soil samples. Statistical analyses revealed no significant difference at p>0.05 between Total Heterotrophic Bacterial (THB) and Hydrocarbon Utilizing Bacterial (HUB) counts, suggesting that most of the bacteria present in the sampled sites were hydrocarbon utilizers. Findings from this study suggest the presence of indigenous putative hydrocarbon utilizing bacteria in the crude-oil polluted soil of Obagi town. Hence, a promising potential exists for future bioremediation studies on the site.

scholarly journals Enhancement of the soil quality of an oil-polluted ultisol using livestock wastes

2020 ◽  
Vol 12 (2) ◽  
pp. 387-398
Author(s):  
Sylvia O. OGOANAH ◽  
Uzoamaka N. NGWOKE ◽  
Edokpolor O. OHANMU ◽  
Pascal C. OKOYE ◽  
Beckley IKHAJIAGBE
Keyword(s):  
Soil Quality ◽  
Polluted Soil ◽  
Lubricating Oil ◽  
Panicum Maximum ◽  
Potential Candidate ◽  
Bacterial Colony ◽  
Total Hydrocarbon ◽  
Hydrocarbon Content ◽  
Total Hydrocarbon Content

The study investigated the enhancement of soil quality of an oil-polluted ultisol using livestock wastes. Top soil (0 - 10 cm) was obtained as a pooled sample and polluted with spent lubricating oil at 10% w/w. The soil was subsequently amended with sun-dried goat (GT), rabbit (RB), and poultry (PG) dung at 10% w/w on dry weight basis both in singles, double-mixed, and triple-mixed combinations. Twelve weeks after treatment application, results showed that there was a 93.9% decrease (p<0.05) in bacterial colony count in the oil-polluted soil compared to the control. Penicillium notatum and Aspergillus niger as well as Bacillus sp. and Proteus sp. were the prominent fungal and bacterial species identified respectively. The most abundant plant in the soil seed bank was Panicum maximum with 10.4% abundance and this showed possible involvement of the plant in remediation of oil-pollution. The total hydrocarbon content of the oil-polluted soil was 9984.0 mg/kg, compared to 3170.6 mg/kg when amended with RB+GT, implying 76.77% remediation efficiency. Among several trials employed in this study, the combination of rabbit and goat wastes proved to be more effective in reducing the total hydrocarbon content of oil-polluted soil and therefore, is recommended as a potential candidate for application in the bioremediation of such soil.

scholarly journals Empirical Characterization of Heavy Metals in Crude Oil Spill Sites in Emohua, Rivers State, Nigeria

2021 ◽  
Vol 2 (5) ◽  
pp. 24-28
Author(s):  
Nnamdi Michael Ahiamadu ◽  
Ify L. Nwaogazie ◽  
Yusuf O. L. Momoh
Keyword(s):  
Heavy Metals ◽  
Surface Water ◽  
Oil Spill ◽  
Environmental Protection Agency ◽  
Surface Soil ◽  
Soil Samples ◽  
Petroleum Resource ◽  
Significant Difference ◽  
Rivers State ◽  
Pb Concentration

The study assessed the concentration of heavy metals in three oil spill sites in Emohua local government area in Rivers State, Nigeria. Soil samples were collected at depth 0-30cm for surface soil samples and up to 10m for sub-surface soil samples depending on the depth of borehole. Groundwater samples were collected from drilled boreholes while the surface water samples were collected from fishponds or water bodies (rivers) close to the oil spill sites. The samples taken from the oil spill sites were analysed to determine the level of concentration of 10 Department of Petroleum Resource (DPR) specified heavy metals (Cd, Zn, Cu, Pb, Cr, Ba, Ni, Hg, As, and Co). BUCK Scientific Atomic Absorption Spectrophotometer (AAS) was used in detecting the concentration of the heavy metals. For the surface soil, Pb concentration in site A and B were significantly higher than what was obtained at site C, with a mean concentration of 219.70, 130.01 and 3.41mg/kg respectively for the three sites. The mean lead (Pb) concentration obtained in the surface soil was within DPR and United State Environmental Protection Agency (USEPA) acceptable limits. Barium also has significant concentration in both the surface soil and sub-surface soil. Kruskal Wallis test indicated significant difference in the Pb, Cd, Zn, Cu, Cr and Ba concentration in surface/topsoil among the three sites and also indicated significant difference in the concentrations of Pb, Cd, Cr, Ni, Ba and As in sub-surface soil among the sites. Little heavy metal concentration was found in both the groundwater and surface water. The study showed that even if some heavy metals were detected at the oil spill sites, they do not pose any serious health risk, as all the heavy metals in the four environmental media at the three sampling sites were below the national limit stipulated by the Department of Petroleum Resource (DPR), Nigeria.

scholarly journals Total hydrocarbon content (THC) testing in liquid oxygen (LOX) systems

2015 ◽  
Vol 101 ◽  
pp. 012083
Author(s):  
B J Meneghelli ◽  
R E Obregon ◽  
H R Ross ◽  
B J Hebert ◽  
J P Sass ◽  
...  
Keyword(s):  
Liquid Oxygen ◽  
Total Hydrocarbon ◽  
Hydrocarbon Content ◽  
Total Hydrocarbon Content

scholarly journals Percentage Bioremediation Assessment of Spent Mushroom Substrate (SMS) and Mucor racemosus in Hydrocarbon Contaminated Soil

2020 ◽  
pp. 1-21
Author(s):  
D. N. Ogbonna ◽  
S. A. Ngah ◽  
R. N. Okparanma ◽  
O. Ule ◽  
R. R. Nrior
Keyword(s):  
Crude Oil ◽  
Contaminated Soil ◽  
Petroleum Hydrocarbon ◽  
Heterotrophic Bacteria ◽  
Polluted Soil ◽  
Total Petroleum Hydrocarbon ◽  
Spent Mushroom Substrate ◽  
Mucor Racemosus ◽  
Rivers State ◽  
Hydrocarbon Utilizing Bacteria

Aim: The aim of the study was to assess Percentage Bioremediation of Spent Mushroom Substrate (SMS) and Mucor racemosus in hydrocarbon contaminated soil Place and Duration of Study: A portion of Rivers State University demonstration farmland in Nkpolu-Oroworukwo, Mile 3 Diobu area of Port Harcourt, Rivers State was used for this study. The piece of land is situated at Longitude 4°48’18.50’’N and Latitude 6o58’39.12’’E measuring 5.4864 m x 5.1816 m with a total area of 28.4283 m2. Bioremediation monitoring lasted for 56 days, analysis carried out weekly (per 7 days’ interval). Methodology: Five (5) experimental plots employing the Randomized Block Design were used each having dimensions of 100 x 50 x 30 cm (Length x Breadth x Height) = 150,000cm3. Baseline study of the uncontaminated and the deliberately contaminated agricultural soil was investigated for its microbiota and physico-chemical properties. Two of these plots were designated as pristine (Unpolluted soil) (CTRL 1) and crude oil contaminated soil without nutrient organics and bioaugmenting microbes (CTRL 2); these two serve as controls. Each of the experimental plots, except the control (CTRL 1), was contaminated with 2500 cm3 (2122.25 g) of crude oil giving initial Total Petroleum Hydrocarbon (TPH) value of 8729.00 mg/kg. The crude oil polluted soil in Plot 3 was further treated with 750 ml of Mucor racemosus broth (CS+Muc), Plot 4 was treated with 3000 g of Spent Mushroom Substrate (CS+SMS) while plot 5 was treated with the combination of both (CS+Muc+SMS). The plots were left for 7 days to ensure even distribution and soil-oil bonding. Sampling was done at seven-day interval (Day 1, 7, 14, 21, 28, 35, 42, 49, 56).  Physicochemical parameters monitored were pH, Temperature, Nitrogen, Phosphorus, Potassium, and Total Petroleum Hydrocarbon (TPH) throughout the experimental period. Microbial parameters monitored were Total Heterotrophic Bacteria (THB), Total Heterotrophic Fungi (THF), Hydrocarbon Utilizing Bacteria (HUB) and Hydrocarbon Utilizing Fungi (HUF). Percentage (%) Bioremediation was estimated from percentage (%) reduction of Total Petroleum Hydrocarbon (TPH) from day 1 to day 56 in relation to control plots.  Net % Bioremediation were also assessed to ascertain the actual potential of treatment agents singly or combined. Results: Total Heterotrophic Bacteria (THB) (CFU/g) recorded on day 7 and day 56 of the bioremediation were; day 7; CTRL 1 – US (1.07 x109), CTRL- CS (5.4 x108), CS+Muc (3.0 x108), CS+SMS (4.6 x108) and CS+Muc+SMS (5.0 x108). On day 56, data obtained were CTRL 1 –US (9.4 x108), CTRL 2 –CS (7.2 x109), CS+Muc (3.7 x108), CS+SMS (8.1x108) and CS+Muc+SMS (6.8 x108). The increase in number in the treated plots is a depiction of an increase in activity of the organism and the stimulating effect of bio-organics SMS while the untreated plot CTRL 1-US showed decrease in population at day 56. Similar trend showed for Total Heterotrophic Fungi. Generally, it was observed that the highest growth/ count was recorded at the 7th and 8th week (day 42 or day 49), at the 9th week there was an observable decrease; probably due to depletion of nutrients and other factors such as rainfall and seepage. The Net Percentage Hydrocarbon Utilizing Bacteria and Fungi (Net %HUB and Net %HUF) were highest in Crude Oil contaminated plot treated with Spent Mushroom Substrate (SMS) singly; that is (CS+SMS) (11.02% and 12.07%) and lowest in the uncontaminated soil – Control (CTRL 1 –US) (5.41% and 9.26%) respectively. The trend in decreasing order of Net % Hydrocarbon Utilizing Bacteria were as follows: CS+SMS (11.02%) > CS+Muc+SMS (10.14%) > CS+Muc (9.43%) > CTRL 2 –CS (8.1%) > CTRL 1 –US (5.41%) while Net % Hydrocarbon Utilizing Fungi followed similar trend and were: CS+SMS (12.07%) > CS+Muc+SMS (11.76%) = CS+Muc (11.76%) > CTRL 2 –CS (11.05%) > CTRL 1 –US (9.26%). Evaluation of Amount of Crude Oil or Hydrocarbon remediated and Net %Bioremediation revealed Crude Oil contaminated plot augmented with Mucor racemosus broth singly (CS+Muc) as having the highest bioremediation potential while the least is the untreated soil. The trend is as follows:  CS+Muc (8599.19 mg/kg; 33.93%) > CS+Muc+SMS (8298.95 mg/kg; 32.74%) > CS+SMS (8197.03 mg/kg; 32.34%) > CTRL 2 –CS (166.54 mg/kg; 0.66%) > CTRL 1 –US (85.48 mg/kg; 0.34%) Conclusion: This shows that a single nutrient substrate or augmenting microorganism applied appropriately may have a more positive result, that is; higher bioremediation potential than combined or multiple mixed treatments. It was further observed that microbial counts decreased with time in treatments with augmenting organisms alone but increased considerably in treatments supplement with organics having its peak on the 49th day.   It is therefore recommended that bioremediation of crude oil-polluted soil using bio-augmenting microorganism should be applied appropriately noting the volume: area ratio and be supplemented with efficient nutrient organics after every 49-day interval.

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