Isolation, identification, and crude oil degradation characteristics of a high-temperature, hydrocarbon-degrading strain
Introduction
With the increasing demand for oil, and oil products, in various fields, petroleum hydrocarbon pollution (PHP) is becoming more serious. Such pollution damages both marine, and terrestrial ecosystems, it has attracted much attention (Bao et al., 2012, Oren, 1990). PHP results from the exploitation and transport of oil, and the processing of oil products. In the exploitation and processing of oil, large volumes of waste water and residues containing oil are produced, and crude oil spillages happen frequently in the transporting of oil (Deng et al., 2014). Oil spills often result in both immediate and long-term environmental damage (Ricardo et al., 2013, Suneel et al., 1996). Statistics shows that about 1.3 million tonnes (Bao et al., 2012) of oil have been spilled in the oceans: PHP not only significantly damages the ecosystem in ocean waters and coastal soils, but also influences economic development and the lives of residents.
Microbial biodegradation technology has gained increasing acceptance in the remediation of oil pollution. Compared with traditional physico-chemical treatments, biodegradation is more environmentally friendly, cost-effective, and efficient (Das and Mukherjee, 2007, Zhang et al., 2012). Numerous studies have proved that microbial biodegradation technology serves potentially significant applications (Wentzel et al., 2007). In the remediation of xenobiotic pollutants (such as oil), natural microbial populations are considered the most basic and reliable bioremediation mechanism (Cappello et al., 2007). Many microorganisms can degrade short-chain petroleum hydrocarbons. However, microorganisms which can degrade long-chain petroleum hydrocarbons and complex polycyclic aromatic hydrocarbons (PAHs) are key to the remediation of oil pollution (Kenzo et al., 2008).
The effectiveness of microbial biodegradation is often limited by the low bioavailability of hydrocarbons to microorganisms (Nitschke and Pastore, 2006, Van et al., 2003). Biosurfactants are surface active molecules produced by certain strains, which either adhere to the cell surface or are excreted extracellularly in the growth culture medium (Suneel et al., 1996). During the culturing process, certain microorganisms secrete biosurfactants into the medium which can increase the surface area of hydrophobic substrates by reducing surface tension of the culture, and further increase their bioavailability (Chandankere et al., 2014, Ramos et al., 1991, Rufino et al., 2008). So attention, to date, is focused on hydrocarbon degrading microorganisms with biosurfactant-producing capabilities, and several species have been provided, such as Bacillus, Alcaligenes, Pseudomonas, and Corynebacterium to this end (Calvo et al., 2004, Rengathavasi et al., 2011, Toledo and Gonzalez, 2008, Zhang et al., 2010).
Dagang Oilfield in Tianjin, China is next to the Bohai Sea and the soil close to the mined oil fields suffers from heavy oil pollution and salinisation. Therefore, there are high requirements impinging upon the microbial consortium responsible for remediating oil pollution in the area. Here, a Bacillus licheniformis Y-1 was isolated from a soil with heavy oil-contamination in the Dagang Oilfield. As the bacterial strain shows high degradation capacity for oil, salt, a high alkali bearing capacity, and high temperature resistance, it has research and application significance. The gene of the strain was identified, the growth and its oil degradation behaviour were optimised, and the degradation characteristics of the strain for petroleum hydrocarbons were analysed.
Section snippets
Crude oil
The crude oil used was collected from the oil pipeline of Dagang Oilfield (latitude: 38° 49′ N; longitude: 117° 31′ E). After standing for 48 h, the oil was separated from water and the supernatant crude oil was collected and reserved. 0# diesel was obtained from the Sinopec gas station in Huayuan, Tianjin, China.
Media
T-medium was used as the nutrient medium. The original inorganic salt medium contained: 10 g of NaCl, 1 g of NH4NO3, 0.5 g of KH2PO4, 1 g of K2HPO4, 0.5 g of MgSO4, 0.2 g of CaCl2, 1 mL of
Emulsifying effect and hydrocarbon-degradation rate
By streaking and isolating, four strains, named Y-1, Y-2, Y-3, and Y-4, were obtained. In the degradation experiments conducted with crude oil as the single carbon unit, it was observed that the crude oil in the conical flask inoculated with Y-1 was dispersed extensively in the medium. The solubility of crude oil in water was improved and thereby microorganisms and oil came into contact more effectively, which accelerated the degradation. Furthermore, the degradation rate of Y-1 for oil reached
Discussion
A hydrocarbon-degrading strain (Y-1) which applied oil as the single carbon unit in its growth was isolated from heavily polluted soil around the production region of the Dagang Oilfield in Tianjin, China. Results showed that the strain had the closet relative with B. licheniformis and the typical biochemical and physiological characteristics of strain Y-1 also meet the standards of B. licheniformis in Bergey's Manual of Determinative for Bacteriology. Based on this, the strain was judged to
Conclusion
A high-efficiency hydrocarbon-degrading strain (Y-1) was isolated from heavily oil-contaminated soil from around the Dagang Oilfield, Tianjin, China. It was identified as a type of B. licheniformis. The strain showed strong tolerance to high salinity, alkalinity, and temperature. It produced emplastic at high temperatures which could be applied as a surfactant to intensify the emulsifying effect. The strain could not only utilise short-chain alkanes, but also degrade long-chain alkanes with
References (32)
- et al.
Biodegradation of crude oil using an efficient microbial consortium in a simulated marine environment
Mar. Pollut. Bull.
(2012) - et al.
Surfactant activity of a naphthalene degrading Bacillus pumilus strain isolated from oil sludge
J. Biotechnol.
(2004) - et al.
Properties and characterization of biosurfactant in crude oil biodegradation by bacterium Bacillus methylotrophicus USTBa
Fuel
(2014) - et al.
Crude petroleum-oil biodegradation efficiency of Bacillus subtilis and Pseudomonas aeruginosa strains isolated from a petroleum-oil contaminated soil from North-East India
Bioresour. Technol.
(2007) - et al.
Isolation and characterization of a novel hydrocarbon-degrading bacterium Achromobacter sp. HZ01 from the crude oil-contaminated seawater at the Daya Bay, southern China
Mar. Pollut. Bull.
(2014) - et al.
Isolation and characterization of two crude oil-degrading yeast strains, Yarrowia lipolytica PG-20 and PG-32, from the Persian Gulf
Mar. Pollut. Bull.
(2012) - et al.
Isolation and characterization of crude oil degrading bacteria from the Persian Gulf (Khorramshahr provenance)
Mar. Pollut. Bull.
(2014) - et al.
Production and properties of a surfactant obtained from Bacillus subtilis grown on cassava wastewater
Bioresour. Technol.
(2006) Estimation of the contribution of halobacterial to the bacterial biomass and activity in solar salterns by the use of bile salts
FEMS Microbiol. Lett.
(1990)- et al.
Production of bioemulsifier by Bacillus subtilis, Alcaligenes faecalis and Enterobacter species in liquid culture
Bioresour. Technol.
(2008)
Comparison of oil composition changes due to biodegradation and physical weathering in different oils
J. Chromatogr. A
Isolation and identification of biosurfactant producing and crude oil degrading Pseudomonas aeruginosa strains
Chem. Eng. J.
Characterization and biotechnological potential of petroleum-degrading bacteria isolated from oil-contaminated soils
Bioresour. Technol.
Lipopeptide biosurfactant production bacteria Acinetobacter sp. D3-2 and its biodegradation of crude oil
Environ. Sci.: Processes Impacts
Microbial community dynamics during assays of harbour oil spill bioremediation: a microscale simulation study
J. Appl. Microbiol.
Isolation, identification, and characterization of a novel, oil-degrading bacterium, Pseudomonas aeruginosa T1
Curr. Microbiol.
Cited by (54)
The role of microorganisms in petroleum degradation: Current development and prospects
2023, Science of the Total EnvironmentBiodegradation of mixed hydrocarbon and eicosane by novel Enterococcus mundtii SS1 isolated from automobile service station soil
2023, Sustainable Energy Technologies and AssessmentsBiodegradation of chlortetracycline by Bacillus cereus LZ01: Performance, degradative pathway and possible genes involved
2022, Journal of Hazardous MaterialsCitation Excerpt :Strain LZ01 was identified using conventional physiological and biochemical methods and 16S rRNA gene sequencing (Leng et al., 2016). Genomic DNA was extracted using a genomic DNA Extraction Kit (Omega Bio-Tek Inc., USA) and the 16S rRNA gene was amplified by PCR using primers 27F(5′-AGAGTTTGATCCTGGCTCAG-3′) and 1492R(5′-GGTTACCTTGTTACGACTT-3′) (Liu et al., 2016). PCR products were detected and purified by 1% agarose gel electrophoresis and PCR Clean Up Kit (Shanghai, China).
Experimental study on wax removal and viscosity reduction of waxy crude oil by Ochrobactrum intermedium
2022, Journal of Petroleum Science and EngineeringCitation Excerpt :The isolated strain's entire DNA was extracted using a bacterial DNA extraction kit. To amplify and pulse 16 S rDNA fragments, universal primers 27 F and 1492 R were utilized (Liu et al., 2016; Gao et al., 2017). The sequence of forward primer 27 F is 5′-AGAGTTTGATCMTGGCTCAG-3′, and the sequence of reverse primer 1492 R is 5′-TACGGYTACCTTGTTACGACTT-3'.