Biosurfactant-Producing Bacteria Isolated from Oil Contaminated Soil and its Media Optimization for Enzyme Production

Oil bio-degradation mechanism by microorganisms is requested for an effective microbial remediation of soil contamination by oil spills. The current examination pointed the identification of a biosurfactant producing bacteria for biosurfactant production from oil contaminated sites from Tamil Nadu. The biosurfactant testing screening methods were used to screen the potent strains and sequencing studies were used for Pseudomonas species identification. The bacterial isolate BS17 subjected to be the potent enzyme (Protease, Lipase and Esterase) producer. Among the tested production media, the ground nut oil cake was identified to be the optimum media for protease (0.47069 Unit/ml), lipase (9 Unit/ml) and esterase activity (3.891 Unit/ml) for bacterial isolate BS17. The bacterial isolate BS17 showed greatest lipase (15 Unit/mL) protease (0.8067 Unit/mL) and esterase (4.756 Unit/mL) enzyme activity at pH 9.0. At 35 ℃ bacterial isolate BS17 showed greatest enzyme action in protease (1.2772 Unit/mL), lipase (17 Unit/mL) and esterase (5.2972 Unit/mL) enzyme activity. At 48hrs of incubation period bacterial isolate BS17 showed most extreme enzyme activity in protease (3.361 Unit/mL), lipase (28 Unit/mL) and esterase (8.918 Unit/mL). The sequence of BS17 was deposited in NCBI and Accession number was received [MT337593.1]. Statistical analysis with the minimum significant difference (LSD) test of ANOVA was carried out to determine the oil degradation efficiency. This paper demonstrated the isolated P. aeruginosa (BS17) crude oil biodegradation from oil contaminated land soil sample. Strain BS17 was proved as potent bio-surfactant producer using crude oil by utilizing carbon and energy source in oil degradation mechanism.

The Physics of Interdigitated Dielectrometry Sensors and Application as In-Situ Oil Oxidation Monitoring

<p>Monitoring of hydrocarbon oxidation is of great importance in many industry applications and reliable in-situ measurements are a challenge. In literature, it was shown that new versus degraded hydrocarbons show a change in their dielectric properties. In this thesis, the degradation of the oil was investigated by means of two thermal oil degradation experiments and the Fourier transform infrared spectroscopy. In addition, the impact. on the dielectric properties were determined using a novel type of a dielectric test cell that is temperature compensated. It was found that ketones, acids and moisture were generated through a thermal oil aging process. These products have been found to change in the dielectric properties of the liquid which are reflected through the complex permittivity. Ketones increased largely the real part of the permittivity and organic acids affected predominantly the imaginary part of the complex permittivity in a nonlinear fashion, which could be described using a modified polaron theory model. These measurements served as the base for the development of a novel kind of interdigitated sensor that can measure the dielectric properties such as the relative permittivity and the intrinsic conductivity with high accuracy and precision, without being affected by temperature. This is a crucial step in the development of a suitable in-situ sensor, as it does not need to undergo a complicated temperature curve compensation or calibration using calibration-liquids. The interdigitated sensor, made using cost efficient printed circuit board technology, exhibited an accuracy in measuring the complex permittivity of about 99%. The sensing precision was practically limited by the measurement instrumentation using a developed Faraday shield for the sensor. The sensor was used in an oil degradation experiment. to verify the in-situ capability. These measurements of the relative permittivity and conductivity yielded values such as a degree of oxidation and acidity number. For the first time: it was possible to measure in-situ the complex dielectric properties of liquids at temperatures between 20 °C to 140 °C using interdigitated sensors.</p>

The Physics of Interdigitated Dielectrometry Sensors and Application as In-Situ Oil Oxidation Monitoring

<p>Monitoring of hydrocarbon oxidation is of great importance in many industry applications and reliable in-situ measurements are a challenge. In literature, it was shown that new versus degraded hydrocarbons show a change in their dielectric properties. In this thesis, the degradation of the oil was investigated by means of two thermal oil degradation experiments and the Fourier transform infrared spectroscopy. In addition, the impact. on the dielectric properties were determined using a novel type of a dielectric test cell that is temperature compensated. It was found that ketones, acids and moisture were generated through a thermal oil aging process. These products have been found to change in the dielectric properties of the liquid which are reflected through the complex permittivity. Ketones increased largely the real part of the permittivity and organic acids affected predominantly the imaginary part of the complex permittivity in a nonlinear fashion, which could be described using a modified polaron theory model. These measurements served as the base for the development of a novel kind of interdigitated sensor that can measure the dielectric properties such as the relative permittivity and the intrinsic conductivity with high accuracy and precision, without being affected by temperature. This is a crucial step in the development of a suitable in-situ sensor, as it does not need to undergo a complicated temperature curve compensation or calibration using calibration-liquids. The interdigitated sensor, made using cost efficient printed circuit board technology, exhibited an accuracy in measuring the complex permittivity of about 99%. The sensing precision was practically limited by the measurement instrumentation using a developed Faraday shield for the sensor. The sensor was used in an oil degradation experiment. to verify the in-situ capability. These measurements of the relative permittivity and conductivity yielded values such as a degree of oxidation and acidity number. For the first time: it was possible to measure in-situ the complex dielectric properties of liquids at temperatures between 20 °C to 140 °C using interdigitated sensors.</p>

Response and oil degradation activities of a northeast Atlantic bacterial community to biogenic and synthetic surfactants

Background Biosurfactants are naturally derived products that play a similar role to synthetic dispersants in oil spill response but are easily biodegradable and less toxic. Using a combination of analytical chemistry, 16S rRNA amplicon sequencing and simulation-based approaches, this study investigated the microbial community dynamics, ecological drivers, functional diversity and robustness, and oil biodegradation potential of a northeast Atlantic marine microbial community to crude oil when exposed to rhamnolipid or synthetic dispersant Finasol OSR52. Results Psychrophilic Colwellia and Oleispira dominated the community in both the rhamnolipid and Finasol OSR52 treatments initially but later community structure across treatments diverged significantly: Rhodobacteraceae and Vibrio dominated the Finasol-amended treatment, whereas Colwellia, Oleispira, and later Cycloclasticus and Alcanivorax, dominated the rhamnolipid-amended treatment. Key aromatic hydrocarbon-degrading bacteria, like Cycloclasticus, was not observed in the Finasol treatment but it was abundant in the oil-only and rhamnolipid-amended treatments. Overall, Finasol had a significant negative impact on the community diversity, weakened the taxa-functional robustness of the community, and caused a stronger environmental filtering, more so than oil-only and rhamnolipid-amended oil treatments. Rhamnolipid-amended and oil-only treatments had the highest functional diversity, however, the overall oil biodegradation was greater in the Finasol treatment, but aromatic biodegradation was highest in the rhamnolipid treatment. Conclusion Overall, the natural marine microbial community in the northeast Atlantic responded differently to crude oil dispersed with either synthetic or biogenic surfactants over time, but oil degradation was more enhanced by the synthetic dispersant. Collectively, our results advance the understanding of how rhamnolipid biosurfactants and synthetic dispersant Finasol affect the natural marine microbial community in the FSC, supporting their potential application in oil spills.