scholarly journals Comparative Study on Physicochemical Parameters Study of Oil Polluted Sites and Hydrocarbon Degradation Potentials of Heterotrophic Bacteria in Southern Nigeria

Author(s):  
R. N. Akwukwaegbu ◽  
P. O. Okerentugba ◽  
G. C. Okpokwasili ◽  
H. O. Stanley ◽  
C. J. Ugboma

In this study, hydrocarbon degradation potentials of heterotrophic bacteria isolated from oil-polluted soil were examined; Samples were collected from Sakpenwa, an oil producing community in Tai LGA of Rivers State. The amounts of hydrocarbon in the soil samples were determined using Gas Chromatography-Flame Ionization Detector, GC- FID. The gravimetric analysis showed that the bacteria were capable of utilizing 96.9-99.7% the oil sample. Analysis of variance (ANOVA) carried out at 95% level of confidence showed that the degree of hydrocarbon degradation varied amongst isolates. Pseudomonas aeruginosa and Alcaligenes sp. showed highest degrading activities while Bacillus subtilis showed least activity. This study revealed that indigenous bacterial species possess the requisite gene necessary for hydrocarbon biodegradation. Biodegradation is most often the primary mechanism for contaminant destruction in the environment including petroleum contaminants.

Author(s):  
R. N. Akwukwaegbu ◽  
P. O. Okerentugba ◽  
G. C. Okpokwasili ◽  
H. O. Stanley ◽  
C. J. Ugboma

In this study, hydrocarbon degradation potentials of heterotrophic bacteria isolated from oil-polluted soil were examined. Samples were collected from Sakpenwa, an oil producing community in Tai LGA of Rivers State, Nigeria and analyzed for physicochemical and microbiological properties using standard techniques. Hydrocarbon utilizing bacteria (HUB) were isolated by vapour phase transfer method using mineral salt medium. The biodegradation study was carried out on a standard laboratory shaker for 30 days in Bushnell -Haas agar supplemented with 5% of crude oil. Fifteen (15) bacterial isolates were screened for hydrocarbon degradation potentials of which five isolates exhibited high hydrocarbon degradability.  The following parameters were monitored using each of the five isolates and a consortium during the biodegradation study: Colour change, Optical density (OD), pH, Total Petroleum Hydrocarbon (TPH), Total Hydrocarbon Contents (THC) and Total Cuturable Heterotrophic Bacterial Counts (TCHBC). The mean TCHBC ranged from 1.65×107 to 2.27×108cfu/ml while the mean Total Culturable Hydrocarbon Utilizing Bacterial Counts ranged from 1.09×104 to 3.9×105. The optical density varied from 0.09±0.02 - 2.57±0.00 and pH ranged from 2.98±0.09 - 6.98±0.09. The optical density varied to .09±0.02 - 2.57±0.00 and pH ranged from 2.98±0.09 -0.98±0.09. The gravimetric analysis showed that Bacillus sp., Pseudomonas sp. Alcaligenes sp. and Acinetobacter sp. were able to degrade 96.90%, 99.60%, 99.20% and 99.70% of the hydrocarbons respectively. This study demonstrated that indigenous bacterial species were highly efficient in the biodegradation of petroleum hydrocarbons.


Fine Focus ◽  
2016 ◽  
Vol 2 (1) ◽  
pp. 7-14
Author(s):  
Chioma Blaise Chikere ◽  
Chinyere Augusta Ajuzieogu ◽  
Michael Chukwugoziem Miller

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.


1998 ◽  
Vol 37 (4-5) ◽  
pp. 259-262 ◽  
Author(s):  
Bjarne R. Horntvedt ◽  
Morten Rambekk ◽  
Rune Bakke

This paper presents a strategy in which mixed biological cultures are exposed to oscillating concentration levels, to improve the potential for coexistence of desired bacterial species. A mechanistic mathematical model is constructed to investigate and illustrate this strategy. This paper is focused on competition between nitrifying, denitrifying and aerobic heterotrophic bacteria in a CSTR with sludge recycle. For nitrifying and aerobic heterotrophic cultures, the effect of sinusoidal oscillations in DO levels with an amplitude of 1.0 mg/l is a 16% specific growth rate reduction compared to that at a constant DO level. The denitrifiers growth rate is increased by an average of 59%, compared to the constant DO level situation. A similar strategy has been tested in a pilot plant. It is concluded that the influence on specific growth rates is a function of the amplitude of the oscillations. The effects are greatest when concentrations fluctuate around the half saturation concentration of the rate limiting component(s).


Author(s):  
Iheonye Chinonye ◽  
Osuji Leo ◽  
Onyema Mark

Forensic chemical analyses was used to characterize, determine the source and correlate  aliphatic hydrocarbons (AHCs) in water samples collected from Bonny L.G.A, Rivers State. AHCs were extracted from the water samples with n-hexane in a separatory funnel, clean-up achieved by column chromatography using n-hexane and analysis by Gas Chromatography Flame Ionization Detector (GC-FID). The GC chromatogram showed well resolved AHC peaks which distributed from nC9 –nC40. The GC chromatograms of AHCs, with a wide range of low molecular weight hydrocarbons, indicate minimal biodegradation of the oil hydrocarbons in the samples. CPI values from 0.68 to 0.78 for BY-A1, BY-A3, BY-A4 and 0.97 for BY-A2 suggest two sources of oil hydrocarbons. Calculated Pr/Ph ratios showed BY-A1 (2.08), BY-A3 (2.00) and BY-A4 (2.20) were derived from mixed marine and terrestrial source deposited in suboxic environment, while BY-A2 (3.70) was mainly terrigenous source in an oxic environment. A cross-plot of Pr/n-C17 and Ph/n-C18 ratios also showed a tight cluster for samples BY-A1, BY-A3 and BY-A4 which were degraded with sample BY-A2 separate and slightly degraded. Results from this study revealed that the spilled oil was derived from mixed organic sources deposited in an oxic environment with different oil input from external sources showing more terrestrial contribution.


2001 ◽  
Vol 28 (1) ◽  
pp. 158-174 ◽  
Author(s):  
M Gamache ◽  
J F Blais ◽  
R D Tyagi ◽  
N Meunier

Until now, some microbiological studies have made it possible to highlight the role and identification of certain chimiolithotroph microorganisms directly involved in the simultaneous sewage sludge digestion and metal leaching (SSDML process). Moreover, some other studies have established the performance of the SSDML process for the destruction of pathogens. However, until now no study has been carried out to define the equilibrium of the heterotrophic microbial populations during the sludge acidification occurring during the operation of the SSDML process. Hence, the SSDML process was studied in batch and continuous mode employing different types of sludges (Communauté Urbaine de Québec (CUQ)-East primary sludge, Beauceville secondary sludge, and mixture of primary and secondary Valcartier sludge). The equilibrium of heterotrophic microbial populations was investigated along with sludge acidification and solids degradation. The results obtained during the SSDML process on different sludges showed a decrease followed by the destruction of a majority of heterotrophic bacterial species found in fresh sludges. The isolation and characterization of different microbial species showed that only two types of microorganisms persisted: the yeast Blastoschizomyces capitatus and an unidentified fungus.Key words: sewage sludge, simultanous bioleaching and digestion, heterotrophic bacteria, Blastoschizomyces capitatus, fungi.


2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Boutheina Gargouri ◽  
Najla Mhiri ◽  
Fatma Karray ◽  
Fathi Aloui ◽  
Sami Sayadi

Two yeast strains are enriched and isolated from industrial refinery wastewater. These strains were observed for their ability to utilize several classes of petroleum hydrocarbons substrates, such asn-alkanes and aromatic hydrocarbons as a sole carbon source. Phylogenetic analysis based on the D1/D2 variable domain and the ITS-region sequences indicated that strains HC1 and HC4 were members of the generaCandidaandTrichosporon, respectively. The mechanism of hydrocarbon uptaking by yeast,Candida,andTrichosporonhas been studied by means of the kinetic analysis of hydrocarbons-degrading yeasts growth and substrate assimilation. Biodegradation capacity and biomass quantity were daily measured during twelve days by gravimetric analysis and gas chromatography coupled with mass spectrometry techniques. Removal ofn-alkanes indicated a strong ability of hydrocarbon biodegradation by the isolated yeast strains. These two strains grew on long-chainn-alkane, diesel oil, and crude oil but failed to grow on short-chainn-alkane and aromatic hydrocarbons. Growth measurement attributes of the isolates, usingn-hexadecane, diesel oil, and crude oil as substrates, showed that strain HC1 had better degradation for hydrocarbon substrates than strain HC4. In conclusion, these yeast strains can be useful for the bioremediation process and decreasing petroleum pollution in wastewater contaminated with petroleum hydrocarbons.


Microbiome ◽  
2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Olga M. Pérez-Carrascal ◽  
Nicolas Tromas ◽  
Yves Terrat ◽  
Elisa Moreno ◽  
Alessandra Giani ◽  
...  

Abstract Background Cyanobacteria from the genus Microcystis can form large mucilaginous colonies with attached heterotrophic bacteria—their microbiome. However, the nature of the relationship between Microcystis and its microbiome remains unclear. Is it a long-term, evolutionarily stable association? Which partners benefit? Here we report the genomic diversity of 109 individual Microcystis colonies—including cyanobacteria and associated bacterial genomes—isolated in situ and without culture from Lake Champlain, Canada and Pampulha Reservoir, Brazil. Results We identified 14 distinct Microcystis genotypes from Canada, of which only two have been previously reported, and four genotypes specific to Brazil. Microcystis genetic diversity was much greater between than within colonies, consistent with colony growth by clonal expansion rather than aggregation of Microcystis cells. We also identified 72 bacterial species in the microbiome. Each Microcystis genotype had a distinct microbiome composition, and more closely related genotypes had more similar microbiomes. This pattern of phylosymbiosis could be explained by co-phylogeny in only two out of the nine most prevalent associated bacterial genera, Roseomonas and Rhodobacter. These phylogenetically associated genera could enrich the metabolic repertoire of Microcystis, for example by encoding the biosynthesis of complementary carotenoid molecules. In contrast, other colony-associated bacteria showed weaker signals of co-phylogeny, but stronger evidence of horizontal gene transfer with Microcystis. These observations suggest that acquired genes are more likely to be retained in both partners (Microcystis and members of its microbiome) when they are loosely associated, whereas one gene copy is sufficient when the association is physically tight and evolutionarily long-lasting. Conclusions We have introduced a method for culture-free isolation of single colonies from nature followed by metagenomic sequencing, which could be applied to other types of microbes. Together, our results expand the known genetic diversity of both Microcystis and its microbiome in natural settings, and support their long-term, specific, and potentially beneficial associations.


Author(s):  
D. N. Ogbonna ◽  
S. A. Ngah ◽  
R. N. Okparanma ◽  
O. Ule ◽  
R. R. Nrior

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.


Author(s):  
Peters Dikioye Emmanuel ◽  
Blessing Minaopunye Onyegeme- Okerenta ◽  
Kojo, Sarah

Background: Differentiation in oil quality and the volatile component of essential oils (EOs) is associated with climatic conditions, the geographical location of collection sites and other ecological and genetic factors defining its chemotypes. Objective: Hence this study was aimed at characterizing volatile constituents of Aframomum danielli seed collected in Choba, Port Harcourt in Rivers State, South-South region of Nigeria. Methods: Essential oils (EOs) were analyzed using gas chromatography–flame ionization detector (GC-FID). Results: A total of forty-two EO (99.96%) constituents were identified, monoterpenes were 32 (99.93%) and sesquiterpenes: 10 (0.03%) No oxygenated sesquiterpenes were detected. Oxygenated monoterpene was higher consisting of 18 EO compounds; 66.94% while monoterpene hydrocarbons comprised of 14 EO compounds; 32.99%. Chemical constituents in the EO include: 1,8- cineole (50.95%), β-pinene (11.79%) –terpineol (9.15%), γ –terpinene (7.45%), Sabinene (6.03%), - pinene (3.41%), α –terpinenly acetate (3.38%), terpinene-4-of(2.44%) and α-thujene (2.11%). Conclusion: Aframomum danielli from this geographical location could serve as a rich source of 1,8- cineole.


2020 ◽  
Vol 2 (2) ◽  
pp. 12-16
Author(s):  
Obhioze Augustine Akpoka

The capability of indigenous bacteria and microalgae in crude oil effluents to grow in and utilize crude oil as their sole source of carbon and energy provides an environmentally friendly and economical process for dealing with crude oil pollution and its inherent hazards. In view of the toxicity of crude oil spillages to indwellers of the affected ecosystems and the entire affected environment, the isolation of pure bacterial and microalgae cultures from crude effluents is a step in the right direction, particularly for bio-augmentation or bioremediation purposes. The total heterotrophic bacteria count and hydrocarbon utilizing bacteria count, as well as the microalgae count, were determined with the pour plate technique. The physicochemical properties of the effluent samples were also analyzed. Identification of the hydrocarbon utilizing bacteria was performed with phenotypic techniques. The result shows a mean total heterotrophic bacterium count of 5.91 log CFU/ml and a mean microalga count of 4.77 log cells/ml. When crude oil and polycyclic aromatic hydrocarbon (PAH) were used as sole carbon sources, total hydrocarbon utilizing bacteria counts were respectively estimated at 3.89 and 2.89 log CFU/ml. Phenotypic identification of hydrocarbon utilizing bacteria in the crude oil effluents revealed the presence of two main bacterial genera: Streptococcus and Pseudomonas. Data obtained from this study confirmed the biodegradative abilities of indigenous bacterial species, thus, ultimately resulting in the amelioration of the toxicity associated with the crude oil effluents.


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