Efficiency and Kinetics of Assam Crude Oil Degradation by Pseudomonas Aeruginosa AKS1 and Bacillus Sp. AKS2

We report kinetics of Assam crude oil degradation by Pseudomonas aeruginosa AKS1 and Bacillus sp. AKS2, both isolated from Assam refinery sediments. The isolates exhibited appreciable degrees of hydrophobicity, emulsification index and biosurfactant production. Crude oil degradation efficiency of isolates was assessed in (1) liquid medium amended with 1% v/v crude oil and (2) microcosm sediments (125 mg crude oil/ 10 g sand). In liquid culture, the biodegradation rate (k) and half-life (t1/2) values were found to be 0.0383 day -1 and 18.09 days for P. aeruginosa AKS1, and 0.0204 day -1 and 33.97 days in case of Bacillus sp. AKS2. In microcosm sand sediments, the estimated biodegradation rate (k) and half-life (t 1/2) values were 0.0138 day -1 and 50 days for P. aeruginosa AKS1, and 0.0113 day -1 and 61.34 days in case of Bacillus sp. AKS2. The level of nutrient treatment in microcosm sand sediment was 125 µg N & 62.5 µg P/g sediment in case of P. aeruginosa AKS1 and 375 µg N & 37.5 µg P/g sediment in case of Bacillus sp. AKS2. In microcosms without inorganic nutrients, biodegradation rate (k) and half-life (t1/2) values were found to be 0.0069 day -1 and 100 days for P. aeruginosa AKS1 and for Bacillus sp. AKS2, the respective values were found to be 0.0046 day -1 and 150.68 days. Our data provides important information for predictive hydrocarbon degradation in liquid medium and contaminated sediments.

BIODEGRADATION EFFECTS OF CRUDE OIL-POLLUTED WATER USING BACTERIA ISOLATES FROM SUNFLOWER HUSK ON FISH GROWTH: PARAMETRIC OPTIMIZATION USING TAGUCHI APPROACH

Bacteria isolates from sunflower husk were applied for bioremediation of crude oil-contaminated water.Fish weight was monitored in bioremediated water by gravimetric method. Taguchi design matrix was employed for process parameters optimization, which include reaction temperature (20-60oC), inoculums concentration (20-100 CFU/mL), crude oil concentration (50-250 mL/L), reaction time (1-5 hrs), NH4Cl concentration (20-100 mg/L) and K3PO4 concentration (10-50 mg/L) for crude oil degradation and fish growth. Bacteria isolates were characterized by biochemical tests. Water samples were characterized using gas chromatograph-mass spectroscopy (GC-MS), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and carbon-hydrogen-nitrogen (CHN) analysis. Results revealed optimum crude oil degradation of 96.59 ± 0.03 % for 50 mL/L of crude oil in water supplemented with 100 CFU/mL inoculums, 10 mg/L K3PO4 and 10 mg/L NH4Cl at 60oC reaction temperature and 4 hrs reaction time. Also, optimum fish growth of 93.14 ± 0.04 % was achieved in 50 mL/L of crude oil in solution supplemented with 80 CFU/mL inoculums, 10 mg/L K3PO4 and 20 mg/L NH4Cl at 60oC reaction temperature and 5 hrs reaction time. Conclusively, characterization revealed degradation of hydrocarbons in crude oil-contaminated water from heavy into light fractions by the bacteria isolates.

Bioremediation potential of a halophilic bacterium Chromohalobacter salexigens EG1QL3: exopolysaccharide production, crude oil degradation, and heavy metal tolerance

Based on biochemical and phylogenetic analyses, isolated from a salt sample from Lake Qarun (Egypt) a halophilic strain EG1QL3 was identified as Chromohalobacter salexigens. The abilities of EG1QL3 to produce an extracellular polysaccharide, degrade oil, and resist to heavy metals were revealed.

Assessment of Crude Oil Degradation by Mixed Culture of Bacillus subtilis and Pseudomonas aeruginosa at Different Concentrations

Petroleum hydrocarbon (PHCs) contamination of soil, freshwater and air is of global concern. The aim of this study was to assess the extent of crude oil degradation by mixed bacterial culture of different crude oil concentrations using gas chromatography-mass spectrometry (GC-MS). Seven oil samples were collected from petroleum-contaminated fields in Kano state, Nigeria, and screened for crude oil utilizing bacteria. A control sample of soil from an ecological garden (control soil) was also analyzed. Crude oil-degrading bacteria were isolated, enumerated and identified using cultural, morphological and biochemical characteristics, and screened for their ability to utilize Bonny Light Oil as a source of carbon and energy. Bacteria with the highest potential to utilize crude oil were selected and subjected to bioremediation studies at three different pollution levels (5%, 10% and 15%) for 56 days. The residual crude oil was assessed using GC-MS. The results revealed that the mixed culture completely degraded eighteen components ranging from C10 to C25 at 5% crude oil concentration while only C8 to C11 and C8 to C9 were degraded at 10 and 15% respectively. The results of this study indicated the potential of B. subtilis and P. aeruginosa in bioremediation of crude oil contaminated soil.

Biodegradable Capability of the Indigenous Micrococcus sp. Oil Degrading Bacteria Isolated from Oil Contaminated Soil, Motor Workshop Area of Bahror, Alwar, Rajasthan, India.

Crude oil contamination is one of the important issue in the current environment pollution. Physical, chemical and biological methods are applied for bioremediation. Use of microorganisms is one of the most popular methods among them. In this experiment, soil samples were collected from the different motor workshop areas to isolate potential microbes capable of crude oil degradation. Isolation of the crude oil degrading bacteria was followed by enriching the microorganisms by providing suitable growth conditions. The microorganisms those were capable of degrading the crude oil were identified as Bacillus spp., Pseudoxanthomonas spp., Phenylobacterium spp. and Micrococcus spp. by morphological and biological methods. Among them, biodegradation capability of Micrococcus sp. was studied at different oil concentrations.