Crude oil depletion by bacterial strains isolated from a petroleum hydrocarbon impacted solid waste management site in California

Abstract

a b s t r a c tThis research is part of a multidisciplinary research program to develop a bioremediation protocol for a solid waste management (SWM) site in Northern California -a site which is heavily contaminated with petroleum hydrocarbons. In this initial study, 30 bacterial strains were isolated and evaluated for their efficiencies to deplete crude oil. The 3 most efficient bacterial isolates for crude oil depletion were designated as S1BD1, OPKDS2, and OSDS1; they were identified as Serratia proteamaculans, Alcaligenes sp. and Rhodococcus erythropolis, respectively, based on partial 16S rRNA gene sequences. Determination of crude oil depletion efficiency by gas chromatographyemass spectrometry (GC-MS) revealed that Serratia proteamaculans S1BD1 was the most efficient (68.0 ± 1.78%), followed by Alcaligenes sp. OPKDS2 (63.7 ± 3.28%), and Rhodococcus erythropolis OSDS1 (54.9 ± 5.07%). S. proteamaculans S1BD1 was able to deplete a wide spectrum of carbon compounds within the individual components of crude oil. Alcaligenes sp. OPKDS2 was the most efficient at depleting BTEX (91.2 ± 1.90%), and R. erythropolis OSDS1 exhibited a substrate preference of n-alkanes. All three strains exhibited unusually high crude oil depletion efficiencies and tolerated a wide range of salinity and pH levels, which makes them excellent candidates for bioaugmentation of the SWM site.

Growth and Extracellular Enzyme Activity Responses of a Multi-enzymic Strain of Serratia sp. in a Simulated Diesel-contaminated System

“…A range finding test result presented asFig. 3revealed that the bacterium could grow in a medium supplemented with a range of TPH concentration from 0.0042 to 0.0335 µg/mL above which cells started to die as indicated by the two linear positions on the plot.Utilization of petroleum hydrocarbons as sources of carbon and energy by Serratia marcesens and other species had earlier been reported by Rajasekar[22] and Xia et al[23]. The first linear portion correlated significantly, strongly and positively (P=.031<.05; R =.962, R .939, adjusted R 2 =.909; MSE =.409) with WSF-D-TPH concentrations and suggested growth of the bacterium.…”

Enhanced crude oil depletion by constructed bacterial consortium comprising bioemulsifier producer and petroleum hydrocarbon degraders

“…Bacterial isolates used in this study were previously isolated from a solid waste management unit (SWMU) contaminated with petroleum hydrocarbons and heavy metals. Detailed information regarding the strains and the unit can be found in our earlier work (Xia et al, 2017).…”

“…This study was part of a multidisciplinary project to define a strategy for bioremediation of a site called SWMU in California coastal area, which had been exposed to petroleum hydrocarbon and heavy metal contaminants for more than 30 years (Xia et al, 2017). The goal of this study was to study the production of bioemulsifier by Rhodococcus erythropolis OSDS1 previously isolated from the site, and the effect of combining bioemulsifier producer and petroleum hydrocarbon degraders in degrading crude oil contaminants.…”

A high-throughput fluorescence-based assay for rapid identification of petroleum degrading bacteria

“…Bacteria were isolated from native soil taken from Shell Pond in 2016. Isolation methods are described in Xia et al (2017). These strains were kept at 80°C in glycerol stocks.…”