Comparison of Petroleum Hydrocarbons Degradation by Klebsiella pneumoniae and Pseudomonas aeruginosa

Abstract

: The aim of this work was to develop bacterial communities to effectively degrade petroleum hydrocarbons (PHs). We investigated the biotic and abiotic contributors to differences in PHs degradation efficacy between two bacterial strains, Klebsiella pneumoniae (Kp) and Pseudomonas aeruginosa (Pa), screened out from the activated sludge of a petroleum refinery. We characterized the temporal variations in degradation efficacy for diesel and its five major constituents as a sole carbon source and identified more constituents they degraded. The growth characteristics, surface tension, hydrophobicity and emulsifiability of these two strains were measured. We further estimated the relationships between their degradation efficacy and all the biotic and abiotic factors. Results showed that the Pa strain had higher diesel degradation efficacy (58% on Day 14) and utilized more diesel constituents (86%) compared to Kp. Additionally, the growth of the Pa strain in diesel medium was faster than that of the Kp strain. The Pa strain had a lower surface tension and higher hydrophobicity and emulsifiability than Kp, while the surfactant produced by Pa was identified as rhamnolipids. Degradation of PHs was positively related to bacterial growth, hydrophobicity and emulsification but negatively related to surface tension. Overall, differences in degrading capacity for diesel constituents, relative growth rate, and biosurfactant production contributed to the variation in the PHs degradation efficacy of these two bacterial strains.

Comparison of petroleum biodegradation efficiencies of three different bacterial consortia determined in petroleum-contaminated waste mud pit

“…ANOVA test was performed to determine the significant differences in petroleum degradation efficiencies of three different consortia (p ≤ 0.05). SPSS ver.18 software (Chicago, IL, USA) was used to carry out the statistical analysis [28]. The tests of normality were assessed using Kolmogorov-Smirnov and Shapiro-Wilk analyses.…”

“…In a previous study, it was shown that K. pneumoniae had an effect on short-, medium-and longchain n-alkanes via enzyme systems and can be used in bioremediation studies [24]. However, You et al [28] clearly showed that K. pneumoniae only biodegraded hydrocarbons in the range of C 10 -C 14 in diesel. Zhou et al [30] reported that Pannonibacter phragmitetus was resistant to extreme environmental conditions such as hot springs, high alkaline conditions and high salt concentration and plays a role in the detoxification of PAHs and heavy metal chrome reduction in these environmental conditions.…”

Modeling the effects of light wavelength on the growth of Nostoc ellipsosporum

“…Santiesteban-López & López-Malo, 2008;Belda-Galbis et al, 2011;Gupta et al, 2012;Tevatia et al, 2012; Mytilinaios et al, 2014;Pla et al, 2015; Ahmad et al, 2015;Ibrahim et al, 2018;Silva et al, 2018;You et al, 2018;Charlebois & Balázsi, 2019).…”

Microbial Surfactants: Classifications, Properties, Recovery, and Applications

“…The ratio of hydrophilic and hydrophobic moieties in the structure of biosurfactants will determine the degree of polarity and solubility of the biosurfactants in different solvent solutions. Glycolipids such as rhamnolipid and sophorolipid are typically extracted from aqueous solutions by standardised solvent extraction using ethyl acetate [46,48]. For instance, the crude sophorolipid from S. bambicola grown on glucose and refined, bleached, and deodorised (RBD) palm olein substrate has been successfully recovered by ethyl acetate with a total yield of 53.3 g/L [49].…”

“…strain BS29, are effective in removing crude oil and PAHs from soil [60]. The rhamnolipid produced by P. aeruginosa Pa can reduce diesel by 58% in 14 days and degrade a higher carbon number of diesel constituents (C15 to C24) [48]. In another study, P.aeruginosa can degrade hydrocarbon components from C12 to C30, while Acinetobacter Iwoffii was more effective in degrading C11 to C17 hydrocarbon fractions than P.aeruginosa after 48 hours of incubation [61].…”