A strain of bacteria DY-11 for degrading phenanthrene and benzopyrene in oil-contaminated soil and its application

Abstract

The application discloses a strain of bacteria DY-11 for degrading phenanthrene and benzopyrene in oil-contaminated soil and application thereof. The strain is Achromobacter anxifer DY-11, and the preservation number is GDMCC No: 66005. Experiments prove that the strain DY-11 can utilize phenanthrene and benzopyrene as carbon sources to degrade them, and the degradation rates of the phenanthrene and the benzopyrene can reach more than 65% after the strain is cultured in inorganic salt culture solution with the initial concentration of the phenanthrene or the benzopyrene being 50 mg·L ‑1 and 25 mg·L ‑1 respectively for 7 days. Therefore, the strain DY-11 is a strain capable of degrading phenanthrene and benzopyrene and having strong tolerance to the phenanthrene and the benzopyrene, has strong adaptability to polycyclic aromatic hydrocarbons, and has good application potential in biological remediation.

Description

Technical Field

[0001] This invention relates to the field of microbial technology, specifically to a strain of DY-11 that degrades phenanthrene and benzo[a]pyrene in petroleum-contaminated soil and its applications. Background Technology

[0002] With the rapid development of modern industrial processes, industrial pollution is increasingly damaging soil. Polluted soil contains various persistent organic pollutants (POPs), such as polycyclic aromatic hydrocarbons (PAHs). PAHs are ubiquitous in the environment and continuously accumulate, attracting widespread attention. Due to human activities such as mining and agriculture, as well as high background levels in soil environmental conditions, severe pollution and excessive levels of PAHs have occurred in the environment. Furthermore, PAHs are the primary pollutants in and around chemical industrial parks, oilfields, mining areas, and wastewater irrigation areas. Phenylenol, a tricyclic aromatic hydrocarbon, has a very close relationship with the carcinogenicity of PAHs. Due to its unique chemical structure, phenylenol has become a model compound for PAH research. Benzo[a]pyrene, a planar polycyclic aromatic hydrocarbon composed of five fused benzene rings, is a potent carcinogen that can bind to DNA in human cells, forming adducts and inducing gene mutations. Because these two types of substances possess potential carcinogenic, teratogenic, mutagenic, and bioaccumulative properties, they pose significant threats to the ecological environment and human health.

[0003] The natural degradation of toxic and harmful organic pollutants in the environment mainly relies on the metabolic activity of related microorganisms. Bioremediation technology has advantages such as low cost, high efficiency, and no secondary pollution, making it the most promising remediation method for phenanthrene and benzo[a]pyrene pollution. Currently, there are relatively few reported strains that degrade phenanthrene and benzo[a]pyrene, mainly including *Virgibacillus*, *Chryseobacterium*, and *Bacillus*. Since most microorganisms in the environment are unculturable, many microorganisms, especially those with specific functions, cannot be isolated through pure culture. Therefore, screening for strains that can effectively degrade high concentrations of phenanthrene and benzo[a]pyrene has significant application value and practical implications.

[0004] This study reports the strain *Achromobacter anxifer*, which can be isolated from various terrestrial and aquatic habitats. Currently, there are relatively few reports on the degradation of pollutants by *Achromobacter anxifer*, and no studies on the degradation of phenanthrene and benzo[a]pyrene by *Achromobacter anxifer* have been reported, either domestically or internationally. Summary of the Invention

[0005] The first objective of this invention is to provide an Achromobacter anxifer DY-11 strain, with accession number GDMCCNo:66005.

[0006] This invention domesticated and isolated a strain DY-11 (Achromobacter anxifer DY-11) from petroleum-contaminated soil in Ningbo City, Zhejiang Province, which uses high concentrations of phenanthrene and benzo[a]pyrene as carbon sources. The strain was identified, and its growth characteristics and degradation characteristics of phenanthrene and benzo[a]pyrene were studied, providing a reference for the bioremediation of PAH-contaminated environments.

[0007] A second objective of this invention is to provide the application of the aforementioned Achromobacter anxifer DY-11 in the degradation of polycyclic aromatic hydrocarbons.

[0008] Preferably, the polycyclic aromatic hydrocarbons include phenanthrene and benzo[a]pyrene.

[0009] Preferably, the bacterial suspension of Achromobacter anxifer DY-11 is applied to water bodies or soil contaminated with polycyclic aromatic hydrocarbons.

[0010] A third objective of this invention is to provide the application of the aforementioned Achromobacter anxifer DY-11 in the preparation of polycyclic aromatic hydrocarbon degrading bacterial agents.

[0011] A fourth objective of this invention is to provide a polycyclic aromatic hydrocarbon (PAH) degrading bacterial agent containing the aforementioned Achromobacter anxifer DY-11 or its pure culture as an active ingredient.

[0012] A fifth objective of this invention is to provide the application of the aforementioned Achromobacter anxifer DY-11 or bacterial agent in the bioremediation of polycyclic aromatic hydrocarbon contaminated environments.

[0013] Preferably, the polycyclic aromatic hydrocarbon (PAH) pollution of the environment includes PAH-polluted water bodies and / or soil. The PAHs include phenanthrene and benzo[a]pyrene.

[0014] The sixth object of the present invention is to provide a method for degrading polycyclic aromatic hydrocarbons (PAHs), wherein the Achromobacter anxifer DY-11 or the bacterial agent is applied to an environment contaminated with PAHs to degrade the PAHs.

[0015] This invention describes the domestication and isolation of a degrading strain, DY-11, from petroleum-contaminated soil in Ningbo City, Zhejiang Province, which utilizes phenanthrene and benzo[a]pyrene as carbon sources. Based on morphological analysis, 16S rDNA sequencing, and phylogenetic analysis, the strain was identified as *Achromobacter anxifer* DY-11. The optimal growth conditions for DY-11 were: temperature 28℃, pH 7, and no sodium chloride added. 16S rDNA sequencing analysis showed that the strain most closely related to DY-11 was *Achromobacter anxifer* strain LMG 26857 (99.57%). DY-11 can utilize phenanthrene and benzo[a]pyrene as carbon sources, with initial concentrations of phenanthrene and benzo[a]pyrene of 50 mg·L⁻¹. -1 and 25 mg·L -1 After culturing in inorganic salt broth for 7 days, the degradation rate of these strains reached over 65%. Therefore, this strain has good application potential in the bioremediation of polycyclic aromatic hydrocarbons.

[0016] Achromobacter anxifer DY-11 was deposited on March 12, 2025 at the Guangdong Provincial Microbial Culture Collection Center (GDMCC), located at 5th Floor, Building 59, No. 100 Xianlie Middle Road, Guangzhou, Guangdong Province, 510070, China, with accession number GDMCC No:66005. Attached Figure Description

[0017] Figure 1 The front and back sides of strain DY-11 grown on LB solid medium for 12 hours.

[0018] Figure 2 Phylogenetic information for strain DY-11.

[0019] Figure 3 The growth of strain DY-11 under different conditions.

[0020] Figure 4 The degradation efficiency of strain DY-11 in inorganic salt medium containing high concentrations of phenanthrene and benzo[a]pyrene (initial concentrations of phenanthrene and benzo[a]pyrene were 50 mg·L⁻¹) was calculated. -1 and 25 mg·L -1 ). Detailed Implementation

[0021] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but the embodiments do not limit the present invention in any way. Unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional reagents, methods and equipment in this technical field.

[0022] Example 1: Isolation and identification of Achromobacter anxifer DY-11

[0023] 1. Sample Source

[0024] Soil samples were collected from petroleum-contaminated soil in Ningbo City, Zhejiang Province. The samples were acclimatized for a long period of time using high concentrations of phenanthrene and benzo[a]pyrene as carbon sources. Through multiple screenings and purifications, highly efficient phenanthrene and benzo[a]pyrene degrading bacteria were obtained.

[0025] 2. Culture medium

[0026] 2.1 Inorganic Salt Culture Medium

[0027] Inorganic salt culture medium is used for the enrichment culture of microorganisms in samples and for the degradation experiments of phenanthrene and benzo[a]pyrene under pure bacterial conditions. The formulation of this culture medium is shown in Table 1. It is prepared by adding each component to water, stirring to mix thoroughly, and then sterilizing.

[0028] Table 1. Inorganic Salt Culture Medium Formulation

[0029]

[0030]

[0031] 2.2 Nutrient Culture Medium

[0032] Nutrient media are used for the isolation, purification, preservation, and activation of bacteria and other routine microbial cultures. The types and components of the liquid nutrient media used in this experiment are shown in Table 2. If a solid medium is required, simply add 1.5-2% agar powder to the existing medium formula. Unless otherwise specified, the pH of the medium should be adjusted to 7. The preparation method involves adding all components to water, stirring to mix thoroughly, and then sterilizing.

[0033] Table 2. Composition of Luria-Bertani medium (LB)

[0034]

[0035] 3. Domestication, screening, and isolation of bacterial strains

[0036] The collected contaminated soil was added to an enrichment medium (inorganic salt medium) at a concentration of 50 mg·L⁻¹. -1 The concentration of phenanthrene is 25 mg·L⁻¹ -1 Benzo[a]pyrene was used as the degradation substrate and cultured in a 28°C incubator in the dark with shaking. The strain was acclimatized using an inorganic salt medium with phenanthrene or benzo[a]pyrene as the carbon source, with each acclimatization cycle lasting 7 days. A 10% inoculum was then transferred to a fresh enrichment medium with the same culture system, and the enrichment process was repeated three times.

[0037] The fourth-generation enriched culture samples obtained above were separated by dilution plating using a nutrient medium. The plated samples were incubated at the original culture temperature. After approximately 48 hours, distinct single colonies formed on the surface of the medium. Several single colonies with different characteristics were selected based on their morphology, size, color, and transparency, and then streaked onto nutrient medium plates for purification. If single colonies with different characteristics were still observed on the purified plates, they were streaked again until only single colonies with the same characteristics were observed on the same plate. A strain, DY-11, exhibiting high degradation performance against both phenanthrene and benzo[a]pyrene, was screened in the experiment. The purified single colonies were picked and cultured in the appropriate liquid nutrient medium until the logarithmic growth phase. The bacterial suspension was mixed with sterile glycerol and aliquoted into sterile 2mL cryovials (glycerol concentration 15%), and stored at -80℃ for long-term preservation.

[0038] 4. Strain identification

[0039] 4.1 Morphological characteristics

[0040] DY-11 is a bacterium isolated from petroleum-contaminated soil in Ningbo City, Zhejiang Province. After activation, it can form white, round, smooth, slightly convex, opaque, non-spore-forming, and non-motile colonies with a diameter of 1.5 mm after 12 hours of growth on LB agar plates at 28°C under aerobic conditions. Figure 1 ).

[0041] 4.2 Molecular biological characteristics

[0042] Molecular biological characterization mainly involves sequencing and phylogenetic tree construction. Before sequencing and constructing the phylogenetic tree, bacterial DNA needs to be extracted (the rapid bacterial genomic DNA extraction kit used in the experiment is from Beijing Adley Biotechnology Co., Ltd.). For bacterial taxonomic studies, it is usually necessary to amplify the 16S rRNA gene and construct a phylogenetic tree. The amplified gene is a segment of DNA encoding rRNA in prokaryotes, and due to its high conservation, specificity, and suitable sequence length, it is commonly used for bacterial detection and identification.

[0043] Polymerase chain reaction (PCR) is mainly used to amplify different gene fragments. PCR requires different primers (27F and 1492R; Baker et al., 2003). The PCR amplification reaction system consists of: 10× buffer 2.5 μL, Mg... 2+1.5 μL of 25 mmol / L primer, 0.3 μL of dNTP (25 mmol / L), 0.5 μL of forward primer (10 mmol / L), 0.5 μL of reverse primer (10 mmol / L), 0.25 μL of Taq enzyme, 0.1 μL of DNA template, and 19.35 μL of deionized water. PCR amplification conditions: denaturation at 95℃, annealing at 55℃, and extension at 72℃, repeated 30 times, with a final extension at 72℃ for 10 min. After the PCR reaction, the sample was stored at 4℃. After amplifying the desired gene, a gel block was prepared using 0.75-1% agarose and the nucleic acid staining agent GelRed. The PCR product and DNA markers containing fragments of various lengths were added to the gel block, which was then placed in an electrophoresis apparatus filled with TBE (Tris borate) buffer. The apparatus was run at a specific voltage for 20 minutes, then removed and observed under a 300nm UV lamp to confirm successful PCR amplification. The successfully amplified PCR product was then sent to BGI Genomics Co., Ltd. for sequencing, using the same primers as the amplification primers.

[0044] The bacterial 16S rRNA gene sequence obtained from sequencing was uploaded to EzTaxon-e.

[0045] The website (http: / / eztaxon-e.ezbiocloud.net / ) compares submitted sequences with the 16S rRNA gene sequences of recognized typical strains to obtain sequence similarity information. Based on the sequence alignment results, a corresponding typical strain can be selected as the model strain for this experiment. Simultaneously, the 16S rRNA gene sequence of the model strain can be obtained, and a phylogenetic analysis can be constructed to demonstrate the differences between the model strain and the experimentally isolated strain, thereby identifying the isolated strain. Phylogenetic tree construction is performed using the MEGA 5.05 program, typically employing the neighbor-joining method, minimum evolution method, and maximum parsimony method. The neighbor-joining method is the most commonly used, with the expansion value usually set to 1000 iterations.

[0046] A 1404 bp 16S rRNA gene sequence was obtained by PCR and gene sequencing. Comparison of the 16S rRNA gene revealed a 99.57% genetic similarity between this strain and *Achromobacter anxifer* strain LMG 26857. Based on these results, the bacterium DY-11 isolated in this invention belongs to the species *Achromobacter anxifer*, and *Achromobacter anxifer* strain LMG 26857 has the GenBank accession number NR 117708.1.

[0047] The 16S rRNA gene sequence of strain DY-11 is as follows:

[0048] TTACCTGCAAGTCGAACGGCAGCACGGACTTCGGTCTGGTGGCGAGTGGCGAACGGG

[0049] TGAGTAATGTATCGGAACGTGCCCAGTAGCGGGGGATAACTACGCGAAAGCGTAGCTA

[0050] ATACCGCATACGCCCTACGGGGGAAAGCAGGGGATCGCAAGACCTTGCACTATTGGAG

[0051] CGGCCGATATCGGATTAGCTAGTTGGTGGGGTAACGGCTCACCAAGGCGACGATCCGT

[0052] AGCTGGTTTGAGAGGACGACCAGCCACACTGGGACTGAGACACGGCCCAGACTCCTA

[0053] CGGGAGGCAGCAGTGGGGAATTTTGGACAATGGGGGAAACCCTGATCCAGCCATCCC

[0054] GCGTGTGCGATGAAGGCCTTCGGGTTGTAAAGCACTTTTGGCAGGAAAGAAACGTCG

[0055] CGGGTTAATACCCCGCGAAACTGACGGTACCTGCAGAATAAGCACCGGCTAACTACGT

[0056] GCCAGCAGCCGCGGTAATACGTAGGGTGCAAGCGTTAATCGGAATTACTGGGCGTAAA

[0057] GCGTGCGCAGGCGGTTCGGAAAGAAAGATGTGAAATCCCAGAGCTTAACTTTGGAAC

[0058] TGCATTTTTAACTACCGAGCTAGAGTGTGTCAGAGGGAGGTGGAATTCCGCGTGTAGC

[0059] AGTGAAATGCGTAGATATGCGGAGGAACACCGATGGCGAAGGCAGCCTCCTGGGATA

[0060] ACACTGACGCTCATGCACGAAAGCGTGGGGAGCAAACAGGATTAGATACCCTGGTAG

[0061] TCCACGCCCTAAACGATGTCAACTAGCTGTTGGGGCCTTCGGGCCTTGGTAGCGCAGC

[0062] TAACGCGTGAAGTTGACCGCCTGGGGAGTACGGTCGCAAGATTAAAACTCAAAGGAA

[0063] TTGACGGGGACCCGCACAAGCGGTGGATGATGTGGATTAATTCGATGCAACGCGAAA

[0064] AACCTTACCTACCCTTGACATGTCTGGAATCCTGAAGAGATTTAGGAGTGCTCGCAAG

[0065] AGAACCGGAACACAGGTGCTGCATGGCTGTCGTCAGCTCGTGTCGTGAGATGTTGGG

[0066] TTAAGTCCCGCAACGAGCGCAACCCTTGTCATTAGTTGCTACGAAAGGGCACTCTAAT

[0067] GAGACTGCCGGTGACAAACCGGAGGAAGGTGGGGATGACGTCAAGTCCTCATGGCCC

[0068] TTATGGGTAGGGCTTCACACGTCATACAATGGTCGGGACAGAGGGTCGCCAACCCGCG

[0069] AGGGGGAGCCAATCCCAGAAACCCGATCGTAGTCCGGATCGCAGTCTGCAACTCGAC

[0070] TGCGTGAAGTCGGAATCGCTAGTAATCGCGGATCAGCATGTCGCGGTGAATACGTTCC

[0071] CGGGTCTTGTACACACCGCCCGTCACACCATGGGAGTGGGTTTTACCAGAAGTAGTTA

[0072] GCCTAACCGCAAGGGGGGCGATAC

[0073] A phylogenetic tree was constructed using the 16S rRNA gene sequence of DY-11 and 16S rRNA gene sequences with high similarity to it, thereby obtaining the homology results between the 16S rRNA gene of DY-11 and 16S rRNA genes with high similarity. The phylogenetic tree constructed using the neighbor-joining method is shown below. Figure 2 Currently, there are few reports on the application of this strain in the environmental field. Therefore, obtaining highly efficient phenanthrene and benzo[a]pyrene degrading bacteria is of significant theoretical and practical importance for the treatment and deep remediation of soils contaminated with phenanthrene and benzo[a]pyrene, as well as PAHs pollution.

[0074] The above results indicate that the strain DY-11 isolated in this invention belongs to the species Achromobacter anxifer, and it is named Achromobacter anxifer DY-11. It was deposited on March 12, 2025 at the Guangdong Provincial Microbial Culture Collection Center (GDMCC), located at 5th Floor, Building 59, No. 100 Xianlie Middle Road, Guangzhou, Guangdong Province, 510070, China, with accession number GDMCC No:66005.

[0075] Example 2: Growth conditions of Achromobacter anxifer DY-11

[0076] 1. Determination of growth temperature: Prepare the liquid nutrient medium required for the growth of the strain and sterilize it in an autoclave. Inoculate the activated bacterial strain into the medium (experimental group), and use uninoculated medium as a control (control group). Incubate the medium at different temperatures for 12 hours. There are three replicates for the control group and the experimental group corresponding to each temperature. The growth of bacteria should be observed daily. When the results are difficult to distinguish with the naked eye, the absorbance of the medium at a wavelength of λ = 600 nm is measured using a visible-ultraviolet spectrophotometer. Finally, the growth temperature and optimal growth temperature range of the new bacteria are determined. The test temperatures are as follows: 18℃, 23℃, 28℃, 33℃, and 38℃.

[0077] 2. Determination of Growth pH: Prepare the liquid nutrient medium required for bacterial growth, and adjust the pH of the culture medium using the following buffer systems: pH 4.0-5.0, 0.1 mol / L sodium citrate and 0.1 mol / L citric acid; pH 6.0-8.0, 0.1 mol / L NaOH and 0.1 mol / L KH2PO4; pH 9.0-10.0, 0.1 mol / L NaHCO3 and 0.1 mol / L Na2CO3; pH 11.0, 0.1 mol / L NaOH and 0.05 mol / L Na2HPO4. Inoculate the bacteria into the culture medium, performing three replicates for each pH. Use uninoculated medium as a control. Incubate the medium at the optimal temperature for new bacterial growth for 12 hours, observing the bacterial growth. When results are difficult to distinguish with the naked eye, measure the absorbance of the medium at a wavelength of λ = 600 nm using a visible-ultraviolet spectrophotometer. Finally, determine the pH at which the new bacteria can grow and the optimal pH range for growth. The pH values ​​tested were as follows: 4.0, 5.0, 6.0, 7.0, 8.0, and 9.0.

[0078] 3. Salt Tolerance: Prepare the liquid nutrient medium required for bacterial growth and adjust the salt concentration. Inoculate the activated new bacteria into the sterilized medium, performing triplicate for each salt concentration. Use uninoculated medium as a control. Incubate the medium at the optimal salinity for bacterial growth for 12 hours and observe bacterial growth. When growth is difficult to distinguish visually, use a visible-ultraviolet spectrophotometer to measure the absorbance of the medium at a wavelength of λ = 600 nm to determine the range of salt concentrations the new bacteria can tolerate. The tested salt concentrations are: 0%, 2%, 4%, 6%, 8%, and 10%.

[0079] like Figure 3 As shown, DY-11 can grow in nutrient broth medium at temperatures ranging from 18 to 38°C, with the optimal growth temperature being the enrichment temperature of 28°C. The bacteria can grow at pH values ​​ranging from 4.0 to 9.0, with the optimal growth pH being 7.0. The bacteria have relatively low salt tolerance and can grow at salt concentrations ranging from 0% to 4%, with the best growth observed without the addition of sodium chloride.

[0080] Example 3: Degradation experiment of phenanthrene and benzo[a]pyrene

[0081] Based on the above experimental results, the optimal growth conditions for the strain were determined to be a temperature of 28℃, pH 7.0, and no NaCl added. Growth and degradation experiments of strain DY-11 in high concentrations of phenanthrene and benzo[a]pyrene were conducted under these conditions.

[0082] The DY-11 strain, in its logarithmic growth phase, was inoculated at a concentration of 10% (the absorbance OD of the original bacterial solution was 0.20, and the cell count in the original bacterial solution was 1.1 × 10⁻⁶ cells according to the traditional plate count method). 7 CFU·mL -1 ) were inoculated separately into cells containing an initial phenanthrene concentration of 50 mg·L⁻¹ -1 Or the initial benzo[a]pyrene concentration is 25 mg·L -1 The culture was carried out in an inorganic salt medium (formulation shown in Table 1, pH 7.0) at 28℃ with shaking for 7 days, and the experiment was repeated in triplicate. The treatment without the addition of strain DY-11 served as the control.

[0083] Each treated sample was used for chemical analysis. The specific steps are as follows:

[0084] (1) Sample pretreatment: Extract each cultured sample with dichloromethane, and simultaneously add 5 μL of a 200 mg / L recovery indicator (for phenanthrene and benzo[a]pyrene treated samples, add deuterated polycyclic aromatic hydrocarbons). After thorough shaking, transfer to a separatory funnel and let stand. Collect the organic phase after separation, return the lower liquid to the shake flask, and repeat extraction with an equal volume of dichloromethane. Combine the extracts and transfer them to a flat-bottomed flask containing an appropriate amount of activated copper sheet for rotary evaporation, concentrating to approximately 2 mL. Add a small amount of n-hexane (approximately 5 mL), and rotary evaporate to 2 mL. Repeat the washing process three times to replace the organic solvent with n-hexane. Purify the concentrated solution using a glass packed column (approximately 9 mm in diameter). The column packing from bottom to top consists of 3 cm of 3% deactivated neutral alumina, 3 cm of 3% deactivated silica gel, and 1 cm of anhydrous sodium sulfate. Activate the column with an appropriate amount of n-hexane, elute the packed column with a 15 mL n-hexane / dichloromethane (1:1 volume ratio) mixture, and collect approximately 15 mL of eluent in a brown reagent bottle. Concentrate the eluent to approximately 0.5 mL by nitrogen blowing, and finally transfer it to a 1.5 mL cell culture flask and freeze. Before analysis, add 5 μL of hexamethylbenzene (200 mg / L) as an internal standard.

[0085] (2) Instrumental Analysis: The PAH content in each treated sample was determined using an Agilent 7890 gas chromatograph coupled with a 5975 mass spectrometer. An Agilent DB 5-MS capillary column (30m length, 0.25mm inner diameter, 0.25μm membrane thickness) was used for separation and analysis. The obtained data were processed using an Agilent chromatography workstation. Quantification of phenanthrene and benzo[a]pyrene was performed using a 6-point calibration curve and the internal standard method. Microbial cell concentration was determined using photoelectric turbidimetry, expressed as OD, which is the optical density value of ultraviolet light transmitted through the measured bacterial solution at a wavelength of 600nm.

[0086] GC-MS analysis showed that strain DY-11 could degrade phenanthrene and benzo[a]pyrene. Figure 4 ), and contains 50 mg·L -1 Concentration of phenanthrene and 25 mg·L -1 After culturing in inorganic salt broth containing benzo[a]pyrene at various concentrations for 7 days, the degradation rates reached over 65%, specifically 82.1% (phenanthrene) and 67.8% (benzo[a]pyrene). This indicates that strain DY-11 is a strain capable of degrading both phenanthrene and benzo[a]pyrene, and exhibits strong tolerance to both compounds.

[0087] The above are merely preferred embodiments of the present invention. It should be noted that the above preferred embodiments should not be considered as limitations on the present invention, and the scope of protection of the present invention should be determined by the scope defined in the claims. For those skilled in the art, several improvements and modifications can be made without departing from the spirit and scope of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. Achromobacteria ( Achromobacter anxifer DY-11, characterized in that, The preservation number is: GDMCC No: 66005.

2. The achromobacter of claim 1, Achromobacter anxifer ) Use of DY-11 in degrading polycyclic aromatic hydrocarbons in a polycyclic aromatic hydrocarbon contaminated environment, the polycyclic aromatic hydrocarbons being phenanthrene and benzopyrene.

3. Use according to claim 2, characterized in that it is The colorless bacteria ( Achromobacter anxifer DY-11 bacterial suspensions are applied to water bodies or soil contaminated with polycyclic aromatic hydrocarbons.

4. The achromobacter of claim 1, Achromobacter anxifer ) The use of DY-11 in the preparation of a polycyclic aromatic hydrocarbon degrading agent, the polycyclic aromatic hydrocarbons being phenanthrene and benzopyrene.

5. A polycyclic aromatic hydrocarbon-degrading bacterial agent, characterized by comprising the polycyclic aromatic hydrocarbon-degrading bacteria according to any one of claims 1 to 4. A composition comprising Achromobacter sp. (Achromobacter sp. DY-11) of claim 1 or a pure culture thereof as an active ingredient, wherein the polycyclic aromatic hydrocarbons are phenanthrene and benzopyrene. Achromobacter anxifer ) DY-11 or a pure culture thereof as an active ingredient, wherein the polycyclic aromatic hydrocarbons are phenanthrene and benzopyrene.

6. The use of the Achromobacter sp. (Achromobacter sp. DY-11) of claim 1 or the bacterial agent of claim 5 in the bioremediation of polycyclic aromatic hydrocarbon-contaminated environments, wherein the polycyclic aromatic hydrocarbons are phenanthrene and benzopyrene. Achromobacter anxifer ) DY-11 or the bacterial agent of claim 5 in the bioremediation of polycyclic aromatic hydrocarbon-contaminated environments, wherein the polycyclic aromatic hydrocarbons are phenanthrene and benzopyrene.

7. Use according to claim 6, characterized in that, The polycyclic aromatic hydrocarbon contaminated environment is a polycyclic aromatic hydrocarbon contaminated water body and / or soil.

8. A method of degrading polycyclic aromatic hydrocarbons, characterized by, The non-pigmented bacillus of claim 1 Achromobacter anxifer ) DY-11 or the bacterial agent of claim 5 is applied to a polycyclic aromatic hydrocarbon contaminated environment to degrade polycyclic aromatic hydrocarbons, the polycyclic aromatic hydrocarbons being phenanthrene and benzopyrene.

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