Acinetobacter venetianus and application thereof in treatment of wastewater containing meta-cresol

Abstract

The application discloses a strain for degrading m-cresol, which is named Acinetobacter venetianus Acinetobacter venetianus , has a strain number of GXGD-YZ-2600 and a preservation number of GDMCC No: 68638. The strain has the ability of stably growing and efficiently degrading m-cresol in the range of 15-45 DEG C and 0-7% salinity. Under the condition of 30 DEG C, 1% salinity and 100 mg / L initial m-cresol concentration, the removal rate of the strain to m-cresol is up to 83.9%. The method for treating m-cresol-containing wastewater by using the strain has the characteristics of high efficiency, environmental protection and low cost, is suitable for treating m-cresol-containing wastewater in petrochemical and chemical industries and has a wide application prospect, and provides a new microbial resource and technical support for biological treatment of difficult-to-degrade phenolic pollutants.

Description

Technical Field

[0001] This invention belongs to the field of environmental microbiology technology, specifically relating to a strain of Acinetobacter velifolia and its application in treating wastewater containing m-cresol. Background Technology

[0002] In high-salinity organic wastewater discharged from the petrochemical, coal chemical, and fine chemical industries, m-cresol is a typical recalcitrant and toxic component. This type of wastewater is affected by production cycles, seasonal climate, and circulating cooling systems, resulting in drastic temperature fluctuations between 15 and 45°C, and total salinity (as NaCl) often reaching 0.5 wt% to 7 wt%. The synergistic stress of temperature and salinity leads to an imbalance in the microbial community structure of conventional activated sludge systems, often resulting in m-cresol removal rates of less than 40%, making it difficult for effluent to consistently meet standards.

[0003] The meta-methyl group on the benzene ring of m-cresol creates significant steric hindrance, requiring a specific dioxygenase system for microbial ring-opening mineralization. High-salt environments induce osmotic imbalance in cells, altering the conformation of intracellular enzyme active sites and inhibiting the expression of degradative enzymes. Current research largely focuses on m-cresol degradation under single environmental factors (such as salt tolerance or temperature tolerance only), lacking a systematic understanding of the biodegradation process under dual temperature and salt stress, thus limiting the application of functional bacteria in complex practical working conditions.

[0004] Traditional activated sludge processes and conventional biofilm processes suffer from the loss of functional bacteria and the detachment of biofilms when subjected to temperature and salinity shocks, resulting in long system recovery periods. While physicochemical methods (Fenton oxidation, ozone oxidation, and resin adsorption) can serve as emergency measures, they suffer from drawbacks such as high reagent costs, secondary pollution, and difficulty in continuous and stable operation. Therefore, screening a functional bacterium that possesses wide temperature adaptability, a certain degree of salt tolerance, and the ability to efficiently degrade m-cresol from complex environments is a key pathway to solving the problem of treating industrial wastewater containing m-cresol at its source.

[0005] Acinetobacter spp. Acinetobacter Acinetobacter veneriense is a group of Gram-negative bacteria widely distributed in the natural environment, possessing strong environmental adaptability and metabolic diversity. Among them, Acinetobacter veneriense... Acinetobacter venetianus Originally isolated from marine environments, it possesses a unique cell membrane structure and metabolic enzyme system, enabling it to grow within a relatively wide temperature range (20–40°C) and a certain salinity range (0–3.5% NaCl, with some strains tolerating up to 9% for short periods). It exhibits strong tolerance to temperature fluctuations and salinity stress. Previous studies have shown that… A. venetianus It can degrade aromatic compounds such as alkanes and phenols, but no information has been found regarding Acinetobacter veneriense. Acinetobacter venetianusReports on the degradation of m-cresol. m-cresol has a meta-methyl group on its benzene ring, making its biodegradation more difficult than that of phenol, requiring specific metabolic enzyme systems to achieve ring-opening mineralization. Therefore, screening for enzymes that can utilize Acinetobacter venetianis is crucial. Acinetobacter venetianus The discovery of strains that degrade m-cresol is of significant theoretical and practical value for expanding the application of these strains in petrochemical wastewater treatment. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a strain of Acinetobacter venetianus that addresses the shortcomings of the prior art.

[0007] The technical problem to be solved by the present invention is to address the shortcomings of the prior art by providing an application of Acinetobacter venetianus in the degradation of m-cresol.

[0008] Another technical problem to be solved by the present invention is to provide an application of Acinetobacter venetianus in the treatment of wastewater containing m-cresol.

[0009] Another technical problem to be solved by the present invention is to provide a method for treating wastewater containing m-cresol.

[0010] The final technical problem to be solved by this invention is to provide a microbial inoculant.

[0011] To solve the above-mentioned technical problems, the technical solution provided by the present invention is as follows:

[0012] The first aspect of this invention provides a strain of Acinetobacter veneriense, which is classified and named Acinetobacter veneriense. Acinetobacter venetianus The strain number is GXGD-YZ-2600, which was deposited on July 17, 2026 at the Guangdong Provincial Center for Microbial Culture Collection, with accession number GDMCC No: 68638. The deposit address is 5th Floor, Building 59, No. 100 Xianlie Middle Road, Guangzhou, Guangdong Province.

[0013] The Acinetobacter veneris described herein possesses salt and heat resistance, and can grow under conditions of salinity of 0 to 7% and / or temperature of 15 to 45°C.

[0014] Acinetobacter venereum Acinetobacter venetianus The 16S rDNA nucleotide sequence of GXGD-YZ-2600 is shown in SEQ ID NO:1; the Acinetobacter venereum... Acinetobacter venetianus The colonies of GXGD-YZ-2600 are milky white and opaque, with neat edges, round shape, and smooth and moist surface. Under an optical microscope, the individual cells are short rod-shaped and often arranged in pairs.

[0015] Acinetobacter venereum Acinetobacter venetianusThe temperature range of GXGD-YZ-2600 is 15 ~ 45℃, with an optimal growth temperature of 28 ~ 32℃. It has the ability to degrade m-cresol within a wide temperature range of 15 ~ 45℃.

[0016] Acinetobacter venetum Acinetobacter venetianus GXGD-YZ-2600 has a salinity tolerance range of 0 to 7%, with an optimal growth salinity of 0 to 2%, and it has the ability to degrade m-cresol within a salinity range of 0 to 7%.

[0017] A second aspect of the present invention provides the use of the aforementioned Acinetobacter veneris in the degradation of m-cresol.

[0018] A third aspect of the present invention provides the application of the aforementioned Acinetobacter veneris in the treatment of wastewater containing m-cresol.

[0019] Wherein, the total salt content in the m-cresol-containing wastewater is 0-7% by mass, and / or the m-cresol content is 0.4 g / L or less.

[0020] In some embodiments, the total salt content in the m-cresol-containing wastewater is 1 to 7% by mass, and / or the m-cresol content is 0.2 g / L or less.

[0021] In some embodiments, the total salt content in the m-cresol-containing wastewater is 1 to 3% by mass, and / or the m-cresol content is 0.1 g / L or less.

[0022] In some embodiments, the total salt content in the m-cresol-containing wastewater is 2-3% by mass, and / or the m-cresol content is 0.1 g / L or less.

[0023] In some embodiments, the total salt content in the m-cresol-containing wastewater is 0, 1%, 2%, 3%, 4%, 5%, 6%, or 7% by mass, and / or the m-cresol content is 0.06, 0.08, 0.1, 0.15, 0.2, 0.3, or 0.4 g / L.

[0024] A fourth aspect of the present invention provides a method for treating wastewater containing m-cresol, wherein the Acinetobacter veneris is inoculated into the wastewater containing m-cresol to carry out a biological reaction.

[0025] In the wastewater containing m-cresol, the total salt content is 0-7% by mass, and / or the m-cresol content is less than 0.4 g / L.

[0026] In some embodiments, the total salt content in the m-cresol-containing wastewater is 1 to 7% by mass, and / or the m-cresol content is 0.2 g / L or less.

[0027] In some embodiments, the total salt content in the m-cresol-containing wastewater is 1 to 3% by mass, and / or the m-cresol content is 0.1 g / L or less.

[0028] In some embodiments, the total salt content in the m-cresol-containing wastewater is 2-3% by mass, and / or the m-cresol content is 0.1 g / L or less.

[0029] In some embodiments, the total salt content in the m-cresol-containing wastewater is 0, 1%, 2%, 3%, 4%, 5%, 6%, or 7% by mass, and / or the m-cresol content is 0.06, 0.08, 0.1, 0.15, 0.2, 0.3, or 0.4 g / L.

[0030] The inoculation amount of Acinetobacter venereum was 10. 6 ~ 10 8 CFU / mL.

[0031] The biological reaction is carried out under aerobic conditions with a temperature of 15-45℃, a pH of 6-8, and a carbon-to-nitrogen ratio of 10-20:1.

[0032] In some embodiments, the biological reaction is carried out under aerobic conditions at a temperature of 25-45°C, a pH of 6-8, and a carbon-to-nitrogen ratio of 10-20:1.

[0033] In some embodiments, the biological reaction is carried out under aerobic conditions at a temperature of 25-35°C, a pH of 6-8, and a carbon-to-nitrogen ratio of 10-20:1.

[0034] The carbon-nitrogen ratio is the mass ratio of COD or BOD5 to total nitrogen.

[0035] The Acinetobacter veneris exists in either a free or immobilized state.

[0036] A fifth aspect of the present invention provides a microbial inoculant comprising the aforementioned Acinetobacter veneriense.

[0037] The dosage form of the microbial agent includes at least one of liquid, powder, and granules.

[0038] In some embodiments, the microbial agent is calcium alginate gel beads immobilized with Acinetobacter veneris.

[0039] Beneficial effects:

[0040] Acinetobacter venetianum provided by this invention Acinetobacter venetianusGXGD-YZ-2600 exhibited excellent m-cresol degradation performance over a wide temperature and salinity range. Under conditions of 30°C, 1% salinity, and an initial m-cresol concentration of 100 mg / L (COD concentration of 236 mg / L), the strain reduced COD to 38 mg / L within 7 days, achieving a m-cresol removal rate as high as 83.9%. At a salinity of 3%, the removal rate remained at 76.3% after 7 days; at 5% salinity, the removal rate was 61.9% after 7 days; and at 7% salinity, the removal rate was 48.7% after 7 days. Under extreme temperature conditions of 15°C and 45°C, the removal rates after 7 days were 46.6% and 47.9%, respectively. Acinetobacter venetianus GXGD-YZ-2600 not only has a wide temperature and salinity adaptability range, but also can effectively degrade m-cresol under high salinity conditions. It is suitable for the treatment of petrochemical wastewater with large temperature and salinity fluctuations, showing important application potential in the field of biological treatment of complex industrial wastewater. Attached Figure Description

[0041] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, and the advantages of the present invention in the above and / or other aspects will become clearer.

[0042] Figure 1 Acinetobacter venetianis strain obtained by screening in this invention Acinetobacter venetianus Colony photos of GXGD-YZ-2600.

[0043] Figure 2 Acinetobacter veneriense Acinetobacter venetianus Optical microscope image of GXGD-YZ-2600.

[0044] Figure 3 Acinetobacter veneris from Example 2 Acinetobacter venetianus Statistical chart of the removal rate of 100 mg / L m-cresol by GXGD-YZ-2600 at a temperature of 30℃ and a salinity of 1%.

[0045] Figure 4 Acinetobacter venetianis strain from Example 3 Acinetobacter venetianus Statistical chart of the removal rate of m-cresol by GXGD-YZ-2600 at different concentrations under the conditions of 30℃ and 1% salinity.

[0046] Figure 5 Acinetobacter veneris from Example 4 Acinetobacter venetianus Statistical chart of the removal rate of 100 mg / L m-cresol by GXGD-YZ-2600 under different temperature conditions.

[0047] Figure 6 Acinetobacter venetianis strain from Example 5 Acinetobacter venetianusStatistical chart of the removal rate of 100 mg / L m-cresol by GXGD-YZ-2600 under different salinity conditions. Detailed Implementation

[0048] The present invention will be further described below with reference to the following embodiments. It should be understood that the following embodiments are for illustrative purposes only and are not intended to limit the present invention.

[0049] Unless otherwise specified, the experimental methods used in the following examples follow standard experimental procedures in the field of biology; and the reagents and materials used are commercially available unless otherwise specified.

[0050] Acinetobacter venetianum provided by this invention Acinetobacter venetianus GXGD-YZ-2600 is a Gram-negative bacterium isolated from petrochemical wastewater. Its colony morphology on LB solid medium is characterized by being milky white, opaque, with neat, round edges, and a smooth, moist surface. Under an optical microscope, it appears as short rods with blunt, rounded ends, measuring 0.9–1.5 μm in length and 0.5–0.8 μm in width.

[0051] Acinetobacter venetum Acinetobacter venetianus The temperature range for GXGD-YZ-2600 is 15 ~ 45℃, with the optimal growth temperature being 28 ~ 32℃; the salinity range is 0 ~ 7%, with the optimal growth salinity being 0 ~ 2%.

[0052] The MSM (Mineral Salts Medium) formulation used in the following examples is as follows: Na₂HPO₄ 6 mg / L, KH₂PO₄ 1.5 mg / L, MgSO₄·7H₂O 0.2 g / L, CaCl₂·2H₂O 0.02 g / L, FeSO₄·7H₂O 0.01 g / L, m-cresol (added as needed), NH₄Cl (added as needed), NaCl (added as needed), pH adjusted to 7.0, and sterilized at 121°C for 20 minutes. MSM medium uses m-cresol as the sole carbon source and NH₄Cl as the sole nitrogen source. The m-cresol and NH₄Cl content in the MSM medium is adjusted according to the experimentally determined carbon-to-nitrogen ratio. For example, when m-cresol is 100 mg / L, the theoretical COD in the medium is approximately 236 mg / L, so NH₄Cl is added accordingly at 48 mg / L to maintain a carbon-to-nitrogen ratio of 20:1. The carbon-to-nitrogen ratio of the MSM medium used in the following examples is 20:1. The salinity of the MSM medium was adjusted using NaCl.

[0053] In the following examples, COD was determined using the potassium dichromate standard method (Determination of Chemical Oxygen Demand in Water - Dichromate Method GB 11914-89) to ensure the scientific validity and comparability of the data.

[0054] Example 1: Isolation, screening, domestication, and identification of strains

[0055] 10 mL of petrochemical wastewater (from a petrochemical plant in Jieyang, Guangdong, originating from the petroleum refining process) was added to 90 mL of MSM medium containing 60 mg / L m-cresol and 20 mg / L glucose (a small amount of glucose was added initially to better promote bacterial growth). The medium was incubated at 30℃ and 180 r / min with shaking for 5 days to enrich the microbial community capable of degrading m-cresol. After incubation, the medium was serially diluted 10-fold, and samples were taken from each dilution. -5 10 -6 10 -7 0.15 mL of each bacterial suspension was evenly spread onto the surface of MSM solid agar plates containing 80 mg / L m-cresol and incubated at 30°C for 3–7 days. Colony growth was observed. Obvious colonies on the plates were picked and purified again using the dilution-spreading method in multiple rounds until homogeneous pure cultures were obtained. Several strains capable of growing on MSM solid agar plates containing 80 mg / L m-cresol were successfully isolated, providing candidate bacterial sources for subsequent domestication and identification.

[0056] To further improve the tolerance and degradation capacity of the strains to m-cresol, four rounds of gradient acclimatization culture were conducted on several isolated strains. The acclimatization process used MSM basal medium, with m-cresol added to concentrations of 20 mg / L, 40 mg / L, 60 mg / L, and 80 mg / L, simulating the environmental pressure of gradually increasing pollutant concentration. Each round of culture lasted 3 days, with the temperature maintained at 30℃, the shaking speed at 180 r / min, the pH controlled at 7.0, and the salinity adjusted to 1% (NaCl content of 10 g / L). This method induced the strains to adapt to m-cresol and enhanced their m-cresol degradation capacity.

[0057] After four rounds of gradient domestication, a dominant strain exhibiting good growth ability and outstanding m-cresol degradation effect was screened from several strains and named GXGD-YZ-2600. 16S rDNA gene sequencing and physiological and biochemical identification confirmed that GXGD-YZ-2600 is *Acinetobacter venetianus*. Acinetobacter venetianus The strain was mixed with 25% v / v glycerol protective solution and stored in an ultra-low temperature freezer at -80°C for long-term preservation and subsequent research. The colony morphology characteristics of strain GXGD-YZ-2600 are as follows: Figure 1 As shown, its photograph under an optical microscope is as follows: Figure 2 As shown.

[0058] Example 2 Evaluation of the degradation performance of strain GXGD-YZ-2600 on m-cresol

[0059] The Acinetobacter venereum strain obtained in Example 1 was screened. Acinetobacter venetianus GXGD-YZ-2600 was inoculated into an inorganic salt medium (MSM) with m-cresol as the sole carbon source to verify its ability to degrade m-cresol. The specific method was as follows:

[0060] The culture broth of this strain was centrifuged at 4000 rpm and 4℃ for 10 min. After discarding the supernatant, the bacterial cells were collected and inoculated into prepared MSM liquid medium to achieve an initial bacterial concentration of 10. 7 The culture medium contained 100 mg / L m-cresol and had a salinity of 1%. The initial chemical oxygen demand (COD) of the medium was measured to be 236 mg / L, all derived from m-cresol, and was used to simulate a petrochemical high-salt organic pollution environment.

[0061] The experimental culture conditions were set at a constant temperature of 30℃ with shaking at a speed of 180 r / min to ensure that the bacteria were in full contact with the pollutant and in an aerobic degradation environment. The total culture period was 7 days, during which samples were taken daily at regular intervals to measure the COD value of the culture medium. COD, as a measure of the concentration of the organic pollutant m-cresol, was used to assess the strain's ability to degrade m-cresol. To verify the reliability of COD changes, a blank control group without inoculated strains was set up, with the same culture conditions as the experimental group, to eliminate interference from factors such as the self-degradation or volatilization of m-cresol on COD.

[0062] The experimental results are shown in Table 1 and Figure 3 As shown, the COD value in the culture medium decreased day by day with the extension of the culture time. By day 4, the COD value had dropped to 52 mg / L, indicating that most of the pollutants had been degraded, with a degradation rate of 78.0%. By day 7, the COD value had dropped to 38 mg / L, with a degradation rate of 83.9%. The COD of the blank control group fluctuated by about 5% over 7 days, proving that the degradation of m-cresol was almost entirely achieved by the biological metabolism of the strain.

[0063] Table 1 Strains Acinetobacter venetianus Degradation effect of GXGD-YZ-2600 on 100 mg / L m-cresol

[0064]

[0065] To more accurately assess the degradation kinetics, COD removal rate (η) was used for quantification, and the calculation formula is as follows: .

[0066] Wherein, COD0 is the initial COD concentration (236 mg / L), COD tLet be the COD concentration on day t. Taking day 7 data as an example... .

[0067] The above experimental results show that strain GXGD-YZ-2600 has good m-cresol removal ability throughout the entire culture cycle, with a degradation rate of 83.9% after 7 days.

[0068] Example 3: Experiment on Optimization of m-cresol Concentration

[0069] To determine Acinetobacter veneri Acinetobacter venetianus The optimal substrate concentration and upper tolerance limit for GXGD-YZ-2600 were determined by setting m-cresol concentration gradients: 60, 80, 100, 150, 200, 300, and 400 mg / L (corresponding to COD 144~944 mg / L), with a salinity of 1%. Other experimental conditions and methods were the same as in Example 2. The experimental results are shown in Table 2 and... Figure 4 As shown.

[0070] Table 2 Strains Acinetobacter venetianus GXGD-YZ-2600's effect on the degradation of m-cresol at different concentrations

[0071]

[0072] Experimental results showed that under conditions of 1% salinity and 30℃, the strain *Acinetobacter venetianis*... Acinetobacter venetianus The degradation ability of GXGD-YZ-2600 for m-cresol gradually changed with increasing substrate concentration. At m-cresol concentrations of 60–100 mg / L, the strain exhibited good degradation ability, with 7-day removal rates of 83.7%, 83.0%, and 83.9%, respectively, reaching a maximum of 83.9% at 100 mg / L. At 150 mg / L, the 7-day removal rate was 78.0%. When the m-cresol concentration reached 200 mg / L, the 7-day removal rate was 72.0%. At 300 mg / L and 400 mg / L, the degradation rate significantly decreased to 52.0% and 44.9%, respectively. Considering both degradation efficiency and substrate tolerance, the optimal m-cresol concentration for strain GXGD-YZ-2600 was 60–100 mg / L.

[0073] Example 4: Effect of temperature on the degradation of m-cresol by the strain

[0074] To evaluate the strain Acinetobacter venetianis Acinetobacter venetianus The degradation capacity of GXGD-YZ-2600 for m-cresol under different temperature conditions was investigated. Temperature gradients were set at 15℃, 20℃, 25℃, 30℃, 35℃, 40℃, and 45℃. The m-cresol concentration was 100 mg / L, and the salinity was 1%. Other experimental conditions and methods were the same as in Example 2. The experimental results are shown in Table 3 and...Figure 5 As shown.

[0075] Table 3. Strains at different temperatures Acinetobacter venetianus The degradation effect of GXGD-YZ-2600 on m-cresol

[0076]

[0077] Experimental results showed that the strain Acinetobacter veneriense... Acinetobacter venetianus GXGD-YZ-2600 exhibits m-cresol degradation ability within a temperature range of 15–45°C. The optimal degradation effect is observed at 30°C, with a removal rate of 83.9% after 7 days. At 25°C and 35°C, the removal rates after 7 days are 78.0% and 80.1%, respectively, showing good degradation performance. At 20°C and 40°C, the removal rates after 7 days are 68.2% and 66.1%, respectively, maintaining high degradation activity. However, at extreme temperatures of 15°C and 45°C, the removal rates after 7 days are only 46.6% and 47.9%, respectively, showing a significant decrease in degradation rate. This indicates that excessively low or high temperatures significantly inhibit the m-cresol degradation activity of this strain. This characteristic makes this strain particularly suitable for petrochemical wastewater treatment systems with significant seasonal temperature fluctuations, but it requires the use of temperature control measures under extreme low or high temperature conditions.

[0078] Example 5: Effect of salinity on the degradation of m-cresol by the strain

[0079] To evaluate the strain Acinetobacter venetianis Acinetobacter venetianus The degradation capacity of GXGD-YZ-2600 for m-cresol under different salinity conditions was investigated. Salinity gradients were set at 0%, 1%, 2%, 3%, 4%, 5%, 6%, and 7%, with a m-cresol concentration of 100 mg / L and a reaction temperature of 30℃. Other experimental conditions and methods were the same as in Example 2. The experimental results are shown in Table 4 and... Figure 6 As shown.

[0080] Table 4. Strains under different salinity conditions Acinetobacter venetianus The degradation effect of GXGD-YZ-2600 on m-cresol

[0081]

[0082] Experimental results showed that the strain Acinetobacter veneriense... Acinetobacter venetianusGXGD-YZ-2600 exhibits m-cresol degradation capabilities within a salinity range of 0–7%. The degradation effect is optimal at a salinity of 1%, achieving a removal rate of 83.9% after 7 days. At salinities of 0% and 2%, the removal rates after 7 days are 82.2% and 80.9%, respectively, demonstrating good degradation performance. At a salinity of 3%, the removal rate remains at 76.3% after 7 days. At 4%, the removal rate is 68.6% after 7 days. At 5%, the removal rate is 61.9% after 7 days. At 6%, the removal rate is 48.7% after 7 days. However, under high salinity conditions of 7%, the removal rate drops significantly to only 38.1% after 7 days, indicating a marked decrease in degradation rate. This suggests that excessively high salinity significantly inhibits the m-cresol degradation activity of the strain. This characteristic makes this strain particularly suitable for petrochemical wastewater treatment systems with large salinity fluctuations; however, dilution or pretreatment measures are necessary when the salinity exceeds 6%.

[0083] Example 6: Immobilized Cell Preparation and Reuse Experiment

[0084] Acinetobacter venereum strain Acinetobacter venetianus Collect bacterial cells by centrifugation of GXGD-YZ-2600 culture medium, wash twice with sterile physiological saline, and adjust the bacterial concentration to 10. 9 CFU / mL was used to obtain a bacterial suspension. The bacterial suspension was mixed with 30 g / L sodium alginate solution at a volume ratio of 1:3, and then dripped into 20 g / L calcium chloride solution using a syringe. Cross-linking and solidification were carried out for 2 h to prepare immobilized cells with a diameter of approximately 3 mm. Acinetobacter venetianus GXGD-YZ-2600 sodium alginate gel beads. The sodium alginate gel beads were placed in MSM medium containing 100 mg / L m-cresol and 1% salinity, and cultured at 30℃ and 180 r / min for 7 days. The COD removal rate was then measured.

[0085] After use, the sodium alginate gel beads were washed with sterile physiological saline and then placed back into fresh MSM medium containing 100 mg / L m-cresol and 1% salinity for the next round of degradation experiments. A total of 5 cycles were performed. The experimental results are shown in Table 5.

[0086] Table 5 Results of experiments on the reuse of immobilized cells

[0087]

[0088] Experimental results showed that the removal rate of immobilized cells was 86.4% in the first cycle (7 days), slightly higher than that of free cells (83.9%). This may be because the immobilized carrier provided some protection for the bacteria, reducing the direct toxic impact of m-cresol on the cells. After 5 cycles, the removal rate remained at 80.9%, indicating that immobilized cells have good operational stability and reusability, making them suitable for continuous wastewater treatment processes.

[0089] This invention provides a salt-resistant, heat-resistant Acinetobacter veneris var. m-cresol-degrading strain and its application, along with related ideas and methods. Many methods and approaches exist for implementing this technical solution; the above description is merely a preferred embodiment of the invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this invention, and these improvements and modifications should also be considered within the scope of protection of this invention. All components not explicitly stated in this embodiment can be implemented using existing technologies.

Claims

1. A strain of Acinetobacter veneriense, classified as Acinetobacter veneriense. Acinetobacter venetianus The strain number is GXGD-YZ-2600, and the preservation number is GDMCC No: 68638.

2. The Acinetobacter veneris according to claim 1, characterized in that, The Acinetobacter veneris is salt- and heat-resistant, and can grow under conditions of salinity of 0 to 7% and / or temperature of 15 to 45°C.

3. The use of Acinetobacter veneris as described in claim 1 or 2 in the degradation of m-cresol.

4. The use of Acinetobacter veneris as described in claim 1 or 2 in the treatment of wastewater containing m-cresol.

5. The application according to claim 4, characterized in that, The total salt content in the m-cresol-containing wastewater is 0-7% by mass, and / or the m-cresol content is 0.4 g / L or less.

6. A method for treating wastewater containing m-cresol, characterized in that, The Acinetobacter veneris as described in claim 1 or 2 is inoculated into wastewater containing m-cresol to carry out a biological reaction.

7. The method according to claim 6, characterized in that, The total salt content in the m-cresol-containing wastewater is 0-7% by mass, and / or the m-cresol content is less than 0.4 g / L.

8. The method according to claim 6, characterized in that, The inoculation amount of Acinetobacter venetum was 10. 6 ~ 10 8 CFU / mL; the biological reaction was carried out under aerobic conditions at a temperature of 15-45℃, a pH of 6-8, and a carbon-to-nitrogen ratio of 10-20:1; the Acinetobacter veneris existed in a free or immobilized form.

9. A microbial inoculant, characterized in that, It includes Acinetobacter veneris as described in claim 1.

10. The microbial agent according to claim 9, characterized in that, The dosage form of the microbial agent includes at least one of liquid, powder, and granules.

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