Response of Soil Microorganisms to Oilfield Wastewater

Abstract

Environmental pollution resulting from oil exploitation and exploration has impacted negatively on the biodiversity of the affected areas. Therefore, this study investigated the response of soil microorganisms to oilfield wastewater. The oilfield wastewater and soil samples were collected from an onshore oil producing platform fortnightly for a period of three months and microbiological analyses were performed using standard methods. Soil around pond average counts for THB and HUB (Log10 CFU/g) were 7.32 to 7.35 and 4.16 to 4.22 respectively. Soil 80 m away from pond average range for THB and HUB were 7.38 to 7.40 and 3.32 to 3.34 respectively. For TF and HUF, Soil around the pond mean recorded 4.65 to 4.85 and 4.12 to 4.16 (Log10 CFU/g) respectively. Mean monthly counts for soil 80m away TF and HUF (Log10 CFU/g) were 5.03 to 5.05 and 3.26 to 3.34 respectively. Soil around the pond recorded lower total heterotrophic bacteria count and total fungi count but higher hydrocarbon utilizing bacteria and hydrocarbon utilizing fungi than soil 80 m away. There was significant difference (P<0.05) between the THB and HUB in the various samples. For the fungi count there was no significant difference (P>0.05) between TF and HUF in all the samples except in sample obtained from soil 80 m away from pond. Bacteria species isolated from the study include: Bacillus, Aeromonas, Micrococcus, Staphylococcus, Chryseomonas, Proteus, Pseudomonas, Klebsiella. Apart from Aeromonas and Chryseomonas the rest of the isolate were identified also as hydrocarbon utilizing bacteria. While fungi species isolated includes: Aspergillus fumigates, Aspergillus niger, Aspergillus flavus, Saccharomyces cerevisiae, Geotricum, Trichoderma, Fusarium and Penicillium. Hydrocarbon utilizing fungi that occurred includes: Aspergillus niger, Aspergillus flavus, Fusarium, Penicillium and Saccharomyces cerevisiae. The response of these microorganisms in the oil polluted environment suggests that the isolated bacteria and fungi could utilize the oil as energy and carbon source and could be effective in the cleanup of the polluted sites.

Full text

_____________________________________________________________________________________________________
*Corresponding author: E-mail: omokaro515@yahoo.com;
Journal of Advances in Microbiology
15(4): 1-8, 2019; Article no.JAMB.48135
ISSN:
2456-7116
Response of Soil Microorganisms to Oilfield
Wastewater
Aleruchi Owhonka
1
and Obire, Omokaro
1*
1
Department of Microbiology, Rivers State University, P.M.B. 5080, Port Harcourt, Nigeria.
Authors’ contributions
This work was carried out in collaboration between both authors. Author OA designed the study,
performed the statistical analysis, wrote the protocol and wrote the first draft of the manuscript. Author
OO managed the analyses of the study. Author OO managed the literature searches. Both authors
read and approved the final manuscript.
Article Information
DOI: 10.9734/JAMB/2019/v15i430107
Editor(s):
(1)
Dr. Ashabil Aygan, Professor, Department of Biological Science, Kahramanmaras Sutcu Imam University (KSU), Turkey.
Reviewers:
(1)
Mian Muhammad, University of Malakand, Pakistan.
(2)
Pingping Luo, Chang’an University, China.
(3)
Oshim, Ifeanyi Onyema, Nnamdi Azikiwe University, Nigeria.
Complete Peer review History:
http://www.sdiarticle3.com/review-history/48135
Received 08 January 2019
Accepted 20 March 2019
Published 27 March 2019
ABSTRACT
Environmental pollution resulting from oil exploitation and exploration has impacted negatively on
the biodiversity of the affected areas. Therefore, this study investigated the response of soil
microorganisms to oilfield wastewater. The oilfield wastewater and soil samples were collected
from an onshore oil producing platform fortnightly for a period of three months and microbiological
analyses were performed using standard methods. Soil around pond average counts for THB and
HUB (Log
10
CFU/g) were 7.32 to 7.35 and 4.16 to 4.22 respectively. Soil 80 m away from pond
average range for THB and HUB were 7.38 to 7.40 and 3.32 to 3.34 respectively. For TF and HUF,
Soil around the pond mean recorded 4.65 to 4.85 and 4.12 to 4.16 (Log
10
CFU/g) respectively.
Mean monthly counts for soil 80m away TF and HUF (Log
10
CFU/g) were 5.03 to 5.05 and 3.26 to
3.34 respectively. Soil around the pond recorded lower total heterotrophic bacteria count and total
fungi count but higher hydrocarbon utilizing bacteria and hydrocarbon utilizing fungi than soil 80 m
away.
There was significant difference (P<0.05) between the THB and HUB in the various samples. For
the fungi count there was no significant difference (P>0.05) between TF and HUF in all the samples
except in sample obtained from soil 80 m away from pond.
Original Research Article

Aleruchi and Obire; JAMB, 15(4): 1-8, 2019; Article no.JAMB.48135
2
Bacteria species isolated from the study include: Bacillus, Aeromonas, Micrococcus,
Staphylococcus, Chryseomonas, Proteus, Pseudomonas, Klebsiella. Apart from Aeromonas and
Chryseomonas the rest of the isolate were identified also as hydrocarbon utilizing bacteria. While
fungi species isolated includes: Aspergillus fumigates, Aspergillus niger, Aspergillus flavus,
Saccharomyces cerevisiae, Geotricum, Trichoderma, Fusarium and Penicillium. Hydrocarbon
utilizing fungi that occurred includes: Aspergillus niger, Aspergillus flavus, Fusarium, Penicillium
and Saccharomyces cerevisiae. The response of these microorganisms in the oil polluted
environment suggests that the isolated bacteria and fungi could utilize the oil as energy and carbon
source and could be effective in the cleanup of the polluted sites.
Keywords: Response; oilfield wastewater; pond wastewater; soil, bacteria; fungi.
1. INTRODUCTION
Crude oil exploration and exploitation activities in
Nigeria are major contributors of environmental
pollution in the Niger Delta. Oilfield wastewater is
the associated wastewater of crude oil
production activities. Oilfield wastewater may
contain hydraulic fracturing (HF) fluids, naturally
occurring salts, radioactive materials, heavy
metals, and other compounds from the formation
such as polycyclic aromatic hydrocarbons,
alkenes, alkanes, and other volatile and semi-
volatile organics [1,2].
Increased Petroleum activities, particularly in the
Niger Delta has led to pollution stress on soil and
surface water, due to the discharging of large
quantities of oilfield wastewater without adequate
treatment techniques [3,4]. Oilfield wastewater
containing high organic and inorganic chemicals
poses environmental problems. The main crucial
environmental issues of the oilfield wastewater
are total petroleum hydrocarbon, total solids
(TS), and inorganic chemicals including heavy
metals and polycyclic aromatic hydrocarbons
(PAHs), biochemical and chemical oxygen
demand (BOD and COD), and pathogens [5].
In Nigeria, Oil exploitation companies are known
to discharge oilfield wastewater into Streams or
ponds which are also a threat to the surrounding
soil and groundwater [6]. Accelerated soil quality
change due to oilfield wastewater discharging
with large quantities of nutrients and toxic
substances into the environment has long
become an issue problem in Niger Delta. It is
estimated that over 90% of wastewater from
operations of oil industries in Nigeria is still
discharged to soil, rivers and streams without
adequate treatment. This is largely due to the
fact that most of the oil companies have no
wastewater treatment plants or where they exist
the facilities are inadequate [7,8].
Soil contaminated by industrial effluents has
affected adversely both soil health and crop
productivity. Heavy metals are one of the major
pollutants of interest in the environment because
of its toxicity, persistence and bioaccumulation
problems [9]. Excessive accumulation of
micronutrients and other heavy metals like
cadmium, lead, and nickel in the plants operates
as stress factors causing physiological
constraints leading to decrease vigour and plant
growth [9] and therefore crop yield [10]. The
effects of petroleum activities on the environment
in the Niger Delta are evident through the
pollution of soil and water bodies and human
habitat in the major cities. The oilfield wastewater
contains toxic and hazardous substances that
are detrimental to human health if they enter the
food chain [11].
The objective of this present study therefore was
to investigate the response of soil
microorganisms to oilfield wastewater by
enumerating microorganisms in the oilfield
wastewater, wastewater in pond, soil around the
pond and in soil 80m away from the pond. This
investigation was conducted for a period of three
months (January–March, 2018) regarded as part
of the dry season in the Niger Delta.
2. MATERIALS AND METHODS
2.1 Collection of Oilfield Wastewater and
Soil Samples
Oilfield wastewater was collected from Ogbogu
Flow Station; an onshore oil production platform
located in Ogba Egbema Ndoni local government
Area (ONELGA) of Rivers State, Nigeria. The
Oilfield wastewater samples were collected using
4 Litre capacity plastic bottles and stored in an
ice packed cooler.
On the other hand, the soil samples were
collected from around the pond and 80 meters

Aleruchi and Obire; JAMB, 15(4): 1-8, 2019; Article no.JAMB.48135
3
away from the pond at a depth of 0-15 cm with a
sterile spatula into sterile polythene bags and
stored in an ice packed cooler. The collected and
appropriately labeled oilfield wastewater and soil
samples were immediately transported to the
laboratory for analysis within 24 hours for
processing and analyses. Samples were
collected twice in a month (1
st
and 3
rd
week) for a
period of three months (January, 2018 to March,
2018).
2.2 Media Preparation
Nutrient Agar was used for Total Heterotrophic
bacterial count; Potato dextrose agar was used
for total fungal count while Mineral salt agar
medium prepared according to the modified
minimal salts medium (MSM) composition of
Mills et al. [12] was used for the isolation of total
hydrocarbon utilizing bacteria. Minimal salts
medium (MSM) composition is – [MgSO
4
.7H
2
O
(0.42 g), KCl (0.29 g), KH
2
PO
4
(0.83 g), Na
2
HP0
4
(1.25 g) NaNO
3
(0.42), agar (20 g)] in 1 Litre of
distilled water. The mixture was thoroughly mixed
and autoclaved at 15psi at 121°C for 15mins and
was allowed to cool to 45C. The medium was
prepared by the addition of 1% (v/v) crude oil
sterilized with 0.22µm pore size Millipore filter
paper Moslein France [13] to sterile MSM, which
has been cooled to 45C under aseptic condition.
The MSM and crude oil were then mixed
thoroughly and aseptically dispensed into sterile
Petri dishes to set.
2.3 Microbiological Analysis of the
Oilfield Wastewater and Soil Samples
2.3.1 Determination of total heterotrophic
bacterial (THB) count of oilfield
wastewater and soils
The total heterotrophic bacterial (THB) count was
determined using the nutrient agar and spread
plate technique as described by Prescott et al.
[14]. An aliquot (0.1 ml) of each serially diluted
sample using dilution factors of 10
-5
for Raw
wastewater, 10
-2
for wastewater in the pond, and
10
-4
for all the soil samples was separately
inoculated onto different sterile nutrient agar
plates in triplicates. The plates were incubated at
37°C in an inverted position for 24 hours. After
incubation, colonies that developed on the plates
were counted and only counts of between 30 and
300 were recorded. The average values of
replicate plates was calculated and expressed as
colony forming unit - CFU/ml for oilfield
wastewater and CFU/g for soil samples.
2.3.2 Determination of total fungi count of
samples of oilfield wastewater and soils
The total count of fungi in the samples was also
determined by the spread plate technique. An
aliquot (0.1ml) of serial dilution (10
-2
) of each of
the various samples was plated onto separate
Potato dextrose agar plates to which 0.1 ml of
streptomycin solution was incorporated to
suppress bacterial growth. The plates were
incubated at 28°C for 5-7 days and the discrete
colonies that developed were enumerated as the
viable counts (CFU) of fungi in the oilfield
wastewater and soil samples [6].
2.4 Hydrocarbon Utilizing Bacterial Count
(HUB) of Samples
The population of the hydrocarbon utilizing
bacterial of oilfield wastewater and soil samples
was determined by inoculating 0.1ml aliquot of
the serially diluted (10
-1
and 10
-2
) samples of
oilfield wastewater and 10
-1
of soil samples onto
mineral salt agar media using the spread plate
technique described by Odokuma and Dickson
[15]. The Vapour Phase Transfer method will be
adopted by the use of sterile filter paper discs
that will be soaked in filter sterilized crude oil
which served as the only carbon source in the
mineral salt agar. The sterile crude oil-soaked
filter papers were aseptically transferred to the
inside cover of the inoculated Petri dishes and
incubated for 5 days at room temperature.
Colonies that develop were counted, average of
duplicate colonies calculated colony forming
units per ml of wastewater or per gram soil
calculated.
2.5 Hydrocarbon Utilizing Fungal Count
(HUF) of Samples
Total hydrocarbon utilizing fungal count of oilfield
wastewater and soil samples was determined by
inoculating 0.1 ml of the serially diluted samples -
1 on mineral salt agar. The mineral salt medium
will be supplemented with streptomycin (0.1 ml)
to suppress bacterial growth [6]. The Vapour
Phase Transfer method was adopted by the use
of sterile filter paper discs that were soaked in
filter sterilized crude oil which served as the only
carbon source in the mineral salt agar. The
sterile crude oil-soaked filter papers were
aseptically transferred to the inside cover of the
inoculated Petri dishes and incubated for 5 days
at room temperature. Colonies that develop were
counted, average of duplicate colonies calculated
colony forming units per ml of wastewater or per
gram soil calculated.

Aleruchi and Obire; JAMB, 15(4): 1-8, 2019; Article no.JAMB.48135
4
2.6 Characterization and Identification of
Bacterial and Fungal Isolates from
Samples
The cultural, morphological, microscopic
characteristics of the isolates from the study
were observed and recorded. The morphological
and biochemical tests conducted using the
isolates included Gram staining, motility,
catalase, oxidase, citrate utilization, sugar
fermentation, hydrogen sulphide production,
indole production methyl red and Voges
Proskauer test. Results of the morphological and
biochemical characteristics of the isolates were
compared with those of known Taxa using
Bergey’s manual of determinative bacteriology
[16].
For the presumptive identification of fungal
isolates, pure fungal cultures were observed
while still on plates and after wet mount in lacto-
phenol on slides under the compound
microscope. Observed characteristics such as
vegetative hyphae and reproductive structures
were recorded and compared with the
established identification key of Barnett and
Hunter [17].
2.7 Statistical Analysis
Statistical analysis was also conducted using
Duncan Multiple Range test and Analysis of
variance to determine whether there is significant
difference between the total counts and the
hydrocarbon utilizers.
3. RESULTS
The results of the total heterotrophic bacteria
(THB) and hydrocarbon utilizing bacteria (HUB)
(log
10
CFU/ml) of the oil field wastewaters were:
January 8.26 and 3.15; February 8.30 and 4.11;
March 8.26 and 4.09 respectively. For
wastewaters in pond the THB and HUB were:
January 5.44 and 5.32; February 5.43 and 5.31;
March 5.39 and 5.30 respectively. Soil around
pond mean monthly counts for THB and HUB
(log
10
CFU/g) were: January 7.35 and 4.22;
February 7.33 and 4.16; March 7.32 and 4.16
respectively. Soil 80 m away from pond counts
for THB and HUB were: January7.38 and 3.32;
February 7.40 and 3.34; March 7.40 and 7.32
respectively. Heterotrophic bacteria counts were
higher in the oilfield wastewater in the various
months of study compared to other samples. The
hydrocarbon utilizing bacteria count was higher
in the wastewater pond than other samples. Soil
80 m away from the pond recorded higher total
heterotrophic bacteria count compared to the soil
around the pond. While higher hydrocarbon
utilizing bacteria count were recorded in soil
around the pond.
Mean monthly counts of the total fungi (TF) and
the hydrocarbon utilizing fungi (Log
10
CFU/ml) for
the oilfield wastewaters were: January 4.26 and
3.45; February 4.23 and 3.38; March 4.28 and
3.43 respectively. The mean monthly counts of
the TF and HUF for wastewater in pond were:
January 4.58 and 3.76; February 4.49 and 3.63;
March 4.56 and 3.63 respectively. Soil around
the pond mean monthly counts for TF and HUF
(Log
10
CFU/g) were: January 4.85 and 4.16,
February 4.74 and 4.12; March 4.65 and 4.12
respectively. Mean monthly counts for soil 80m
away TF and HUF were: January 5.05 and 3.26;
February 5.03 and 3.32; March 5.05 and 3.34
respectively. The soil 80m away from the pond
had higher total fungi count than the soil around
pond, while soil around the pond had higher
hydrocarbon utilizing fungi count.
The predominant bacteria and fungi that
were isolated from the various samples are as
shown in Table 2 and Table 3 respectively.
The signs indicates presence (+) and absence (-)
of indicated organisms in the row, for the
various samples in January, February and
March.
Bacillus, Micrococcus, Pseudomonas sp.
occurred in all the samples in the various
months of sampling. Proteus sp was not
isolated in the wastewater samples but only
occurred in the soil samples in all the months of
sampling. Staphylococcus, Chryseomonas and
Klebsiella sp. were not isolated in the soil
samples in the months of sampling but
were isolated in the wastewater samples.
Aeromonas sp only occurred in the soil
around pond in the month of February but was
isolated in the wastewater samples in all the
months.
Aspergillus niger, Aspergillus fumigates and
Penicillium sp. were isolated in the various
samples and in all the months. Fusarium sp. and
Saccharomyces cerevisiae were not isolated in
the soil samples. Geotricum sp was not isolated
in the oilfield wastewater but occurred in all other
samples. Trichoderma sp. was only isolated in
the soil samples.

Fig. 1.
Counts of total heterotrophic bacterial (THB) and hydrocarbon utilizing bacteria (HUB)
Fig. 2.
Counts of total fungi (TF) and hydrocarbon utilizing fungi (HUF)
Microbiology/locations
Oilfield wastewater
Mean
Std. Deviation
Pond water
Mean
Std. Deviation
Soil 80 m away from pond
Mean
Std. Deviation
Soil around pond
Mean
Std. Deviation
0
1
2
3
4
5
6
7
8
9
THB HUB
January
Bacterial count
(Log10 CFU/ml or g)
Month and bacterial group
0
1
2
3
4
5
6
TF
HUF
January
Fungal count
(Log10CFU/ml or g)
Month and Fungal group
Aleruchi and Obire; JAMB, 15(4): 1-8, 2019;
Article no.
5
Counts of total heterotrophic bacterial (THB) and hydrocarbon utilizing bacteria (HUB)
of wastewater and soil
Counts of total fungi (TF) and hydrocarbon utilizing fungi (HUF)
of wastewater and soil
Table 1. Analysis of variable
Report
THB
HUB
THF
Mean
8.2733 3.7833 4.2567
Std. Deviation
0.02309 0.54857 0.02517
Mean
5.4200 5.3100 4.5433
Std. Deviation
0.02646 0.01000 0.04726
Mean
7.3933 3.3267 5.0433
Std. Deviation
0.01155 0.01155 0.01155
Mean
7.3333 4.1800 4.7467
Std. Deviation
0.01528 0.03464 0.10017
THB HUB THB HUB
February
March
Month and bacterial group
Oilfield wastewater
Wastewater in pond
Soil around pond
Soil 80m away from Pond
TF
HUF
TF
HUF
February March
Month and Fungal group
Oilfield wastewater
Wastewater in pond
Soil around pond
Soil 80m away from pond
Article no.
JAMB.48135
Counts of total heterotrophic bacterial (THB) and hydrocarbon utilizing bacteria (HUB)
of wastewater and soil
HUF
3.4200
0.03606
3.6733
0.07506
3.3067
0.04163
4.1333
0.02309
Soil 80m away from Pond
Soil 80m away from pond

Aleruchi and Obire; JAMB, 15(4): 1-8, 2019; Article no.JAMB.48135
6
Table 2. Bacteria isolated from oilfield wastewater and soil samples
Types of bacteria
Oilfield
wastewater
Wastewater in
pond
Soil around
pond
Soil 80 m away
from pond
Bacillus sp + + + + + + + + + + + +
Aeromonas sp + + + + + + -+- - - -
Micrococcus sp + + + + + + + + + + + +
Staphylococcus sp + + + - - + - - - - - -
Chryseomonas sp + + + + - + --- ---
Proteus sp + + + + + - + + + + + +
Klebsiella sp + + + + + + --- ---
Pseudomonas sp + + + + + + + + + + + +
Table 3. Fungi isolated from oilfield wastewater and soil samples
Types of fungi
Oilfield
wastewater
Wastewater in
pond
Soil around
pond
Soil 80m away
from pond
A. niger + + + + + + + + + + + +
A. fumigatus + + + + + + + + + + + +
A. flavus + + - --- + + + + + +
Penicillium sp + + + + + + + + + + + +
Fusarium sp + + + + + + --- ---
Saccharomyces cerevisiae + + + + + + --- ---
Geotricum sp --- + + + -++ + + +
Trichoderma sp --- --- + + + + + +
4. DISCUSSION
Microbial populations play a role in degradation
of hydrocarbon contaminations, Atlas [18] and
Leahy and Colwell [19] reported that the rate of
petroleum hydrocarbon biodegradation in nature
is determined by the populations of indigenous
hydrocarbon degrading microorganisms. Leahy
and Colwell [19] concluded that hydrocarbon
biodegradation depends on the composition of
the microbial community and its adaptive
response to the presence of hydrocarbons.
Heterotrophic bacteria counts were higher in the
oilfield wastewater in the various months of study
compared to other samples. The occurrence of
bacteria in oilfield wastewater despite the
treatment with biocide during the treatment
process could be attributed to organic and
inorganic constituents that serve as nutrients for
bacterial growth. This was also reported by
Wemedo et al. [20] and Marshall and Derinny
[21]. The hydrocarbon utilizing bacteria count
was higher in the wastewater pond than other
samples. This could be as a result of continues
discharge of petroleum products into the
wastewater pond. It has been reported by
several researchers that continuous discharges
of crude oil into the ecosystem may result in
selective increase or decrease in microbial
population [22,23]. There was significant
difference (P<0.05) between the THB and HUB
in the various samples. Soil around the pond
recorded lower total heterotrophic bacteria count
and higher hydrocarbon utilizing bacteria
compared to the soil 80 m away from the pond.
The lower total heterotrophic count could also be
attributed to the toxicity of the oilfield wastewater
on the soil around the pond resulting to the
response of microorganisms that have the ability
to withstand the toxins. Obire and Anyanwu [24]
reported reduction in diversity of species with
increase in concentration of added crude oil was
an index for environmental stresses of oil
hydrocarbons.
The soil 80 m away from the pond had higher
total fungi count than other samples. Higher HUF
counts were observed in the soil around pond
and could be attributed to the presence of
residual crude oil in the polluted soil which
boosts the carbon supply in the soil thereby
favoring the growth of the hydrocarbon utilizing
fungi which were adapted to the quantity of
hydrocarbons in the environment. It was also
observed that total fungi counts were greater
than HUF counts in all the samples in the various
months. There was no significance difference
(P>0.05) between the HF and HUF in all samples
except in soil 80m away from the pond. This
indicates that samples were polluted with
hydrocarbons. The result is in agreement with
that reported by Chikere and Azubuike [25].

Aleruchi and Obire; JAMB, 15(4): 1-8, 2019; Article no.JAMB.48135
7
Bacteria species isolated from the study include:
Bacillus, Aeromonas, Micrococcus,
Staphylococcus, Chryseomonas, Proteus,
Pseudomonas, Klebsiella. Apart from Aeromonas
and Chryseomonas the rest of the isolate were
identified also as hydrocarbon utilizing bacteria.
While fungi species isolated includes: Aspergillus
fumigates, Aspergillus niger, Aspergillus flavus,
Saccharomyces cerevisiae, Geotricum,
Trichoderma, Fusarium and Penicillium.
Hydrocarbon utilizing fungi that occurred
includes: Aspergillus niger, Aspergillus flavus,
Fusarium, Penicillium and Saccharomyces
cerevisiae. The following organisms;
Staphylococcus sp, Fusarium, Chryseomonas
sp, Klebsiella sp, and Saccharomyces cerevisiae
were not isolated in the soil samples while
Trichoderma sp was only isolated in all soil
samples. High numbers of certain oil-degrading
microorganisms from an environment implies that
those organisms are the active degraders of that
oil and may have the ability to produce spores
that may shield them from toxic effects of the
hydrocarbon. The absence of certain species
known to be soil microorganisms in favour of oil
degraders could be detrimental to the
ecosystem. Similar reports were published by
many researchers [3,6,26,27,28].
5. CONCLUSION AND RECOMMENDA-
TIONS
The high population of hydrocarbon utilizers in
the soil around pond suggests that the
hydrocarbon utilizers were adapted to the
quantity of hydrocarbons in the environment and
thereby increased the number of hydrocarbon
utilizers in the polluted area.
The study also revealed that most of the
organisms isolated as total heterotrophic bacteria
and total fungi were part of the utilizers. The
response of these microorganisms in the oil
polluted environment suggests that the isolated
bacteria and fungi could utilize the oil as energy
and carbon source and could be effective in the
cleanup of the polluted sites.
COMPETING INTERESTS
Authors have declared that no competing
interests exist.
REFERENCES
1. Warner NR, Jackson RB, Darrah TH, et al.
Geochemical evidence for possible natural
migration of Marcellus formation brine to
shallow aquifers in Pennsylvania.
Proceedings of the National Academy of
Sciences of the United States of America.
2012;109(30):11961–11966.
2. Kassotis CD, Tillitt DE, Lin CH, McElroy
JA, Nagel SC. Endocrine- disrupting
chemicals and oil and natural gas
operations: potential environmental
contamination and recommendations to
assess complex environmental mixtures.
Environmental Health Perspectives; 2015.
3. Obire O, Amusan FO. The environmental
impact of oilfield formation water on a
freshwater stream in Nigeria. J. Appl. Sci.
Environ. Mgt. 2003;7(1):61-66.
4. Wemedo SA, Obire O. Acute toxicity test of
oilfield wastewater on bacterial community
of soil in Nigeria. Research Journal of
Environmental Toxicology. 2012;6:25-32.
5. Pichtel J. Oil and gas production
wastewater: Soil contamination and
pollution prevention. Applied and Environ-
mental Soil Science. 2016;1-24.
6. Obire O, Wemedo SA. The effect of oil
field wastewater on the microbial
population of soil in Nigeria. Niger Delta
Biologia. 1996;1:77–85.
7. Human Rights Watch interview with Bruce
Powell, zoologist and expert on Niger Delta
ecology, London; 1998.
8. Van Dessel B. The environmental situation
in the Niger Delta, Nigeria, section 5.5.1;
1996.
9. Zouboulis AI, Loukidou MX, Matis KA. Bio-
sorption of toxic metals from aqueous
solutions by bacteria strains isolated from
metal polluted soils. Journal of Process
Biochemistry. 2004;39:90-95.
10. Jaja ET, Obire O. Impact of oilfield waste-
water on soil quality and of soils planted
with various plants. Current Studies in
Comparative Education, Science and
Technology. 2015;2(2):179-196.
11. Rajaram T, Ashutost D. Water pollution by
industrial effluents in India: Discharge
scenario and case for participatory
ecosystem specific local regulation.
Environmental Journal. 2008;40(1): 56-69.
12. Mills AL, Breuil C, Colwell RR.
Enumeration of petroleum-degrading
marine and estuarine microorganisms by
the most probable number method. Can. J.
Microbial.1978;24:552-557.
13. Obire O. Studies on the biodegradation
potentials of some microorganisms
isolated from water systems of two
petroleum producing areas in Nigeria. Nig.
J. Bot. 1988;1:81-90.

Aleruchi and Obire; JAMB, 15(4): 1-8, 2019; Article no.JAMB.48135
8
14. Prescott LM, Harley JP, Klien DA.
Microbiology. 6
th
ed. McGraw Hill London.
2005;135-140.
15. Odokuma LO, Dickson AA. Bioremediation
of a crude oil-polluted tropical rain forest
soil. Glob J Environ Sci. 2003;2:29–40.
16. Bergey DH, John GH. Bergey’s manual of
determinative bacteriology. Baltimore
Williams and Wilkins; 1994.
17. Barnett HL, Hunter BB. Illustrated genera
of fungi imperfecti. 3
rd
Edition, Burgess
Publishing Company, Minneapolis; 1972.
18. Atlas RM. Microbial degradation of
petroleum hydrocarbons: An environmental
perspective. Microbiol. Rev. 1981;45:180–
209.
19. Leahy JG, Colwell RR. Microbial
degradation of hydrocarbons in the
environment. Microbiol. Rev. 1990;54:305–
315.
20. Wemedo SA, Obire O, Akani NP. Bacterial
population of an oilfield wastewater in
Nigeria. Asian J. Biol. Sci. 2012;5:46-51.
21. Marshall TR, Derinny JS. The microbial
ecosystem in petroleum wasteland treat-
ment. Water Sci. Tech. 1988;20:285-291.
22. Okpokwasili GC, Nnubia C. The effects of
drilling fluids on marine bacteria from
Nigerian offshore oilfield. Eviron. Manag.
1995;19:923-929.
23. Okpokwasili GC, Odokuma LO. Effects of
oil spill dispersant and drilling fluids on
substrate specificity on marine bacteria.
Waste Manag. 1996;15:515-520.
24. Obire O, Anyanwu EC. Impact of various
concentrations of crude oil on fungal
populations of soil. Int. J. Environ. Sci.
2009;6:211-218.
25. Chikere CB, Azubuike CC.
Characterization of hydrocarbon utilizing
fungi from hydrocarbon polluted sediments
and water. Nig. J. Biotech. 2014;27:49-
54.
[ISSN:018917131]
26. Okerentugba PO, Ezeronye OU.
Petroleum degrading potentials of single
and mixed microbial cultures isolated from
rivers and refinery effluent in Nigeria. Afr.
J. Biotechnol. 2003;2:288-292.
27. Onifade AK, Abubakar FA.
Characterization of hydrocarbon-degrading
microorganisms isolated from crude oil
contaminated soil and remediation of the
soil by enhanced natural attenuation. Res.
J. Microbiol. 2007;2:149-155.
28. Boboye B, Olukunle OF, Adetuyi FC.
Degradative activity of bacteria isolated
from hydrocarbon-polluted site in Ilaje,
Ondo State, Nigeria. Afr. J. Microbiol. Res.
2010;4:2484-2491.
_________________________________________________________________________________
© 2019 Aleruchi and Obire; This is an Open Access article distributed under the terms of the Creative Commons Attribution
License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any
medium, provided the original work is properly cited.
Peer-review history:
The peer review history for this paper can be accessed here:
http://www.sdiarticle3.com/review-history/48135