Marine bacteria Stutzerimonas balearica WH-1 and its application

Abstract

The present invention discloses marine bacteria Stutzerimonas balearica WH‑1 and its application, belonging to the field of microbial technology. The marine bacterium Stutzerimonas balearica WH‑1 is deposited in the General Microbiological Center of China Microbiological Culture Collection Administration Committee, with a deposit date of April 10, 2024, a deposit number of CGMCC No.30298, and a deposit location in Beijing, China. The marine bacterium Stutzerimonas balearica WH‑1 provided by the present invention is separated and screened from seawater contaminated by promethazine. The strain is adapted to a wide range of salinities and can efficiently degrade triazine herbicides promethazine, sirbazone, amethoxazole and sirbazone, and has an efficient bioremediation effect on marine environments polluted by triazine herbicides promethazine, sirbazone, amethoxazole and sirbazone.

Description

Technical Field

[0001] The present invention relates to a marine bacterium and its application, in particular to a marine bacterium Stutzerimonas balearica WH-1 ​​and its application in degradation of triazine herbicides such as promethazine, simethoate, ametryn and propazine belong to the field of microbial technology. Background Art

[0002] Triazine herbicides are a new type of environmental pollutant found in the marine environment in recent years. In addition to being used in agriculture to control annual grasses and broadleaf weeds, they are also widely used in marine aquaculture to clean ponds and remove large algae. Triazine herbicides are frequently detected in my country's coastal marine environment, such as near the Yellow River estuary, Laizhou Bay, Rushan offshore, the Yellow Sea, Bohai Sea, Hainan Bamen Bay, etc., where promethazine, amethoxam, cypermethrin, and cypermethrin were detected; triazine herbicides have also been detected many times in foreign marine environments. It can be seen that triazine herbicide pollution has expanded to the marine ecological environment.

[0003] The chemical properties of triazine herbicides are relatively stable. The photodegradation half-life of promethazine in seawater is 55d to 70d, and the effective period of cypermethrin in soil is 35d to 45d. Triazine herbicides can exist in the marine environment and marine organisms for a long time, and produce chronic low-dose toxic effects on marine animals. The marine ecological effects caused by triazine herbicides have attracted widespread attention. At present, the pollution remediation of triazine herbicides in the marine environment has been the focus of attention in recent years. Microbial remediation technology is the main biological remediation method for organic pollutant pollution remediation. It has the advantages of economy, high efficiency, greenness, no secondary pollution, and simple operation. Therefore, it is urgent to develop a fast, efficient and safe microbial remediation method for triazine herbicide pollution in the marine environment.

[0004] At present, the microbial degradation strains of triazine herbicides in domestic and foreign literature mainly come from freshwater environments. For example, Chinese patent CN202311106530.X discloses a strain of Exiguobacterium SWFU-DH02 ( Exiguobacterium sp. SWFU-DH02), which was isolated from a sugarcane field where promethazine was used for a long time, can degrade the triazine herbicide promethazine; Chinese patent CN202311387663.9 discloses a strain of Pseudomonas M3511 ( Pseudomonas silesiensis M3511), which was isolated from pesticide-contaminated soil in Xinjiang Uygur Autonomous Region, can degrade multiple pesticides including chloranil, pendimethalin, promethazine, clopyralid and chlorpyrifos; Chinese patent CN200780040279.4 discloses a Nocardia-like strain MTD22 ( Nocardioides sp.Strain MTD22 was isolated from soil and can degrade methylthiotriazines, chlorinated triazines and methoxylated triazines.

[0005] So far, no strains have been found Stutzerimonas balearica It and its similar strains are used to study the biodegradation of triazine herbicides such as promethazine, simetropium, ametryn and propazine. Summary of the invention

[0006] The object of the present invention is to provide a marine bacterium which can simultaneously degrade promethazine, simetryn, ametryn and propazine and has high degradation efficiency and wide adaptability to salinity.

[0007] In order to achieve the above object, the present invention adopts the following technical solution:

[0008] Marine bacteria Stutzerimonas balearica WH-1 ​​is deposited in the General Microbiology Center of China Microorganism Culture Collection Administration, the deposit date is April 10, 2024, the deposit number is CGMCC No.30298, and the deposit unit is Beijing, China.

[0009] The aforementioned marine bacteria Stutzerimonas balearica The application of WH-1 in the degradation of triazine herbicides includes promethazine, simetryn, ametryn and propazine.

[0010] The invention is beneficial in that: the marine bacteria S tutzerimonas balearica WH-1 ​​was isolated and screened from seawater in natural sea areas contaminated by promethazine. The strain is adaptable to a wide range of salinities and can efficiently degrade triazine herbicides promethazine, simetropium, ametryn and propazine. It has a highly efficient bioremediation effect on marine environments (including seawater and marine sediments) contaminated by promethazine, simetropium, ametryn and propazine, and is relatively safe for marine shellfish, marine copepods and marine microalgae. The strain was used to treat samples contaminated by promethazine, simetropium, ametryn and propazine (all at a concentration of 50 mg·L -1 ) after 7 days of exposure to seawater contaminated by prometryne, simetropium, ametryne and propazine, the biodegradation rates were 92.8%, 88.3%, 77.4% and 83.9%, respectively, and the degradation half-lives were 2.99 days, 2.73 days, 3.32 days and 4.01 days, respectively. The strain was used to treat seawater contaminated by prometryne, simetropium, ametryne and propazine (all at a concentration of 50 mg·L -1 ) After 7 days in the polluted marine sediments, the biodegradation rates of promethazine, simenon, ametryn and chlorpyrifos were 88.5%, 83.3%, 80.9% and 79.4%, respectively, and the degradation half-lives were 3.01 days, 3.67 days, 3.97 days and 4.23 days, respectively. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 yes Stutzerimonas balearica Colony morphology of WH-1;

[0012] Figure 2 yes Stutzerimonas balearica The shape of WH-1 bacteria;

[0013] Figure 3 yes Stutzerimonas balearica Phylogenetic tree diagram of WH-1;

[0014] Figure 4 yes Stutzerimonas balearica WH-1 ​​strain growth test results at different temperatures;

[0015] Figure 5 yes Stutzerimonas balearica WH-1 ​​strain growth test results at different salinities;

[0016] Figure 6 yes Stutzerimonas balearica WH-1 ​​strain growth test results at different pH values;

[0017] Figure 7 yes Stutzerimonas balearica Statistical results of the degradation rate of promethazine by WH-1 at different inoculation rates;

[0018] Figure 8 yes Stutzerimonas balearica The statistical results of the degradation rate of promethazine, simetropium, ametryn and propazine by WH-1 at the same inoculation amount (5%);

[0019] Fig. 9 It is a statistical result chart of biodegradation rate of promethazine, simetropium, ametryn and propazine in polluted seawater samples;

[0020] Fig.10 It is a statistical result chart of biodegradation rate of promethazine, simenon, ametryn and propazine in contaminated marine sediment samples. DETAILED DESCRIPTION

[0021] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] 1. Collection of seawater samples.

[0023] In May 2022, surface seawater samples were collected from the aquaculture tailwater discharge channel of the Yellow River Delta nearshore aquaculture area contaminated by prochloraz (N37°37′16.92″, E118°56′35.7″) and filtered with a sterile filter membrane. The filter membrane was placed in a 100mL sterile centrifuge tube, the lid was tightened and sealed with a sealing film, placed in an ice box and transported to the laboratory for use.

[0024] 2. Strain enrichment, screening, separation and purification.

[0025] 1. Preparation of culture medium.

[0026] Enrichment medium: weigh 19.45g sodium chloride, 5.98g magnesium chloride, 3.24g sodium sulfate, 1.80g calcium chloride, 0.55g potassium chloride, 0.16g sodium carbonate, 0.08g potassium bromide, 0.034g strontium chloride, 0.022g boric acid, 0.004g sodium silicate, 0.0024g sodium fluoride, 0.0016g sodium nitrate and 0.008g disodium hydrogen phosphate, heat and dissolve in 1000mL distilled water, and adjust the pH value to 7.6. Take 100mL of enrichment medium and dispense it into 250mL conical flasks, add 20 small glass beads with a diameter of 1mm to each flask, sterilize it by high pressure at 121℃ for 20min, and set aside.

[0027] Drug-free plate culture medium: prepare 1000 mL of enriched culture medium, add 15.0 g of agar, heat to dissolve and dispense into 250 mL conical flasks, sterilize at 121°C for 20 min, pour into plates and set aside.

[0028] Drug-containing plate culture medium: prepare 1000 mL of enrichment culture medium, add 100 mg of promethazine and 15.0 g of agar, heat to dissolve and dispense into 250 mL conical flasks, sterilize at 121°C for 20 min, pour into plates and set aside.

[0029] Improved LB medium: weigh 10 g of tryptone, 5 g of yeast extract and 19.45 g of sodium chloride (the sodium chloride concentration of conventional LB medium is 5 g·L -1 ~10g·L -1 ), dissolved in 1000 mL of distilled water, and the pH value was adjusted to 7.0. Take 100 mL of the modified LB medium and dispense it into a 250 mL conical flask, sterilize it by high pressure at 121°C for 20 min, and set aside.

[0030] 2. Enrichment and screening of strains.

[0031] Add promethazine to the enrichment medium to a concentration of 20 mg·L -1 The filter membrane carrying the microorganisms in the seawater sample was cut into pieces and added to the enrichment medium supplemented with promethazine. The mixture was stirred at 25°C and 150 r / min. -1 Carry out enrichment culture. Take the culture and transfer it to new enrichment medium at a transfer rate of 5% every 7 days. Each time the transfer is carried out, the concentration of promethazine in the enrichment medium is gradually increased to 40 mg·L -1 、60mg·L -1 、80mg·L -1 、100mg·L-1 After each transfer, samples were taken after 24 hours of incubation and sent to Shandong Provincial Aquatic Product Quality Inspection Center to detect the residual amount of prometryn by gas chromatography-mass spectrometry to determine the degree of degradation of prometryn.

[0032] Table 1 Degradation rate of promethazine by microorganisms on the filter membrane

[0033]

[0034] As shown in Table 1, with the increase of acclimatization passage number and promethazine concentration, the degradation amount of promethazine by the culture increased gradually within the same period of time. -1 The degradation rate of promethazine reached 58.9%.

[0035] 3. Isolation and purification of strains.

[0036] After the microorganisms on the filter membrane were continuously domesticated and subcultured for 4 times, 1 mL of the 5th generation culture was taken for gradient dilution. 100 μL of 10 -3 , 10 -4 , 10 -5 , 10 -6 The diluted solutions of different dilution multiples were spread on drug-containing plate culture media (respectively marked as plate 1, plate 2, plate 3, and plate 4), and cultured in a constant temperature incubator at 25°C for 7 days.

[0037] Compared with other plates, plate 2 had more types of colonies and a moderate number. Multiple single colonies with different morphologies and colors were picked from plate 2 and streaked and cultured three times to obtain purified strains. The strain with the best growth was selected and recorded as WH-1.

[0038] Add promethazine to the modified LB medium to a concentration of 100 mg / L -1 The strain WH-1 was inoculated into the modified LB medium supplemented with promethazine and then incubated at 150 r·min -1 The strain was cultured on a shaker at 25°C for 24 h and then preserved in 30% glycerol (stored at -70°C) as a backup strain.

[0039] 3. Colony morphology, bacterial shape, and physiological and biochemical characteristics of strain WH-1.

[0040] 1. Colony morphology.

[0041] Under sterile conditions, strain WH-1 was inoculated into drug-free plate medium using the three-line method. After culturing for 24 h, Figure 1 As shown, the colony morphology was observed to be round, about 1.0 mm in diameter, with a smooth surface with protrusions, opaque, and regular edges.

[0042] 2. Bacterial shape.

[0043] Take two loops of freshly cultured strain WH-1 with an inoculation loop, add to 1 mL of sterile water, and mix. Take two copper holes for electron microscopy, cover with aspirated bacterial suspension for 3 minutes, dry the bacterial solution with filter paper, stain with phosphotungstic acid for 1.5 minutes, and dry the phosphotungstic acid with filter paper. Observe the shape of the bacteria under a Hitachi H-7650 transmission electron microscope, such as Figure 2 As shown, strain WH-1 is short rod-shaped and has flagella.

[0044] 3. Physiological and biochemical characteristics.

[0045] Identification by the API 20E bacterial identification system showed that strain WH-1 could assimilate and utilize sodium citrate, tryptophan, and pyruvate, and could oxidize melibiose and arabinose, but could not assimilate and utilize arginine, o-nitrophenyl-galactoside, sodium thiosulfate, Kohn gelatin, mannitol, inositol, sorbitol, rhamnose, sucrose, glucose, and amygdalin; could not hydrolyze lysine, ornithine, and tryptophan, and could not produce indole.

[0046] 4. Species identification of strain WH-1.

[0047] The genomic DNA was extracted by proteinase K cleavage, and 3 μL was taken for electrophoresis detection. The marker was DL9000, and the bands from top to bottom were 9000bp, 5000bp, 3000bp, 2000bp, 1000bp, and 500bp, respectively. The sample volume was 3 μL, and the bright band was 30 ng·μL -1 , the remaining bands were all 10 ng·μL -1 , P1, P2, and P3 are blank controls of extraction reagents.

[0048] The 16S rDNA fragment of strain WH-1 was amplified using the 16S full-length amplification forward primer 8F (nucleotide sequence: 5'-AGAGTTTGATCCTGGCTCAG-3') and reverse primer 8R (nucleotide sequence: 5'-TACGGYTACCTTGTTAYGACTT-3'). The amplified product was detected by 1% agarose gel electrophoresis and then sent to Feifan Standard Technology Service Co., Ltd. for sequencing.

[0049] The sequencing results were analyzed for homology using the BLAST search system and the 16S rDNA sequences of related species collected in the GenBank nucleic acid database, and the phylogenetic tree of strain WH-1 was constructed using the MEGA 7.0 software and the Neighbour-joining method. The construction results are shown in Figure 3 shown.

[0050] After comparative analysis, strain WH-1 and Stutzerimonas balearicaclustered and formed independent internal branches, therefore, strain WH-1 was named Stutzerimonas balearica WH-1.

[0051] 5. Growth of strain WH-1 under different temperature, salinity and pH environments.

[0052] 1. Detection of the growth of strain WH-1 at different temperatures.

[0053] Take 500 μL of WH-1 culture solution grown to the exponential phase and inoculate it into the modified LB medium. -1 The culture was cultured on a shaker at 10°C, 15°C, 20°C, 25°C, 30°C, 35°C, 40°C, and 45°C for 24 h, and the OD of the culture medium at the beginning of the experiment and at 24 h was measured using an ELISA reader. 600 The growth rate of the strain was measured by the OD value of the culture medium at 24 h. 600 The OD of the culture medium at the beginning of the experiment 600 The difference (△OD 600 ) indicates. A blank control group without inoculation was set up. Each experimental group was set up with 3 parallels.

[0054] The results of strain growth test of strain WH-1 at different temperatures are as follows Figure 4 As shown. Figure 4 It can be seen that strain WH-1 can grow at 10℃~45℃, and the optimal growth temperature is 25℃~30℃.

[0055] 2. Detection of the growth of strain WH-1 under different salinities.

[0056] The amount of sodium chloride added to the modified LB medium was adjusted. Specifically, the amount of sodium chloride added was 0 g, 10 g, 20 g, 30 g, 40 g, 50 g, 60 g, 70 g, 80 g, 90 g, and 100 g (dissolved in 1000 mL of distilled water), respectively, so that the salinity of the culture medium was 0, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, and 10%, respectively. 500 μL of WH-1 bacterial solution cultured to the exponential phase was inoculated into the culture medium with different salinities, and the culture medium was incubated at 150 r·min -1 The mixture was incubated at 25 °C for 24 h on a shaker, and the OD of the culture medium was measured at the beginning of the experiment and at 24 h using an enzyme-labeled instrument. 600 The growth rate of the strain was measured by the OD value of the culture medium at 24h. 600 The OD of the culture medium at the beginning of the experiment 600 The difference (△OD 600 ) indicates. A blank control group without inoculation was set up. Each experimental group was set up with 3 parallels.

[0057] The growth test results of strain WH-1 under different salinities are as follows Figure 5As shown. Figure 5 It can be seen that the salinity range for the growth of strain WH-1 is 0-10%, and the optimal salinity is 3%-4%.

[0058] 3. Detection of the growth of strain WH-1 at different pH values.

[0059] The pH value of the modified LB medium was adjusted to 3, 4, 5, 6, 7, 8, 9, and 10, respectively. 500 μL of WH-1 culture solution cultured to the exponential phase was inoculated into the culture medium with different pH values, and the mixture was incubated at 150 r·min. -1 The mixture was incubated at 25 °C for 24 h on a shaker, and the OD of the culture medium was measured at the beginning of the experiment and at 24 h using an enzyme-labeled instrument. 600 The growth rate of the strain was measured by the OD value of the culture medium at 24h. 600 The OD of the culture medium at the beginning of the experiment 600 The difference (△OD 600 ) indicates. A blank control group without inoculation was set up. Each experimental group was set up with 3 parallels.

[0060] The growth test results of strain WH-1 at different pH values ​​are as follows Figure 6 As shown. Figure 6 It can be seen that the pH range for the growth of strain WH-1 is 3-10, and the optimal pH value for growth is 8.

[0061] In summary, strain WH-1 can grow at 10℃~45℃, pH 3-10, and sodium chloride concentration (w / v) 0-10%. The optimal growth temperature is 25℃~30℃, the optimal growth pH is 8, and the optimal salinity is 3%~4%. It has the characteristics of a wide temperature range, strong salt resistance and acid and alkali resistance, and is suitable for use in different marine environments.

[0062] 6. Study the degradation effect of strain WH-1 on promethazine, simenon, ametryn and cypermethrin.

[0063] The above-mentioned improved LB medium was optimized and adjusted according to the optimal salinity (3% to 4%) of strain WH-1. Specifically, the amount of sodium chloride was further increased from 19.45g to 30g, that is, 10g of tryptone, 5g of yeast extract and 30g of sodium chloride were weighed and dissolved in 1000mL of distilled water, and the pH value was adjusted to 7.0 to obtain a high-salt LB medium. 100mL of high-salt LB medium was dispensed into a 250mL conical flask, autoclaved at 121℃ for 20min, and set aside.

[0064] 1. The degradation rate of promethazine by strain WH-1 at different inoculation doses.

[0065] Add 5 mg of promethazine to the sterilized high-salt LB medium to make the final concentration of promethazine in the medium 50 mg·L-1 The strain WH-1 was inoculated into the high-salt LB medium supplemented with promethazine at an inoculum of 0, 0.5%, 1%, 3%, 5%, 10%, 15%, and 20%, respectively. Each group had three parallels and was incubated at 150 r·min -1 The samples were cultured on a shaker at 25°C for 24 hours, and samples were taken at 24 hours and sent to Shandong Aquatic Products Quality Inspection Center for detection of the residual amount of promethazine by gas chromatography-mass spectrometry to determine the degree of degradation of promethazine.

[0066] The statistical results of the degradation rate of promethazine by strain WH-1 at different inoculation rates are shown in Figure 7 .Depend on Figure 7 It can be seen that with the increase of the inoculation amount of strain WH-1, the degradation rate of promethazine increased significantly, and when the inoculation amount exceeded 5%, the degradation rate of promethazine tended to be balanced. Therefore, the optimal inoculation amount of strain WH-1 is 5% to 10%.

[0067] 2. The degradation rate of strain WH-1 on cypermethrin, simetropium, ametryn and cypermethrin at an inoculation dose of 5%.

[0068] 10 mg of prometryn, 10 mg of simetropium, 10 mg of ametryn and 10 mg of propazine were added to the sterilized high-salt LB medium. The concentrations of prometryn, simetropium, ametryn and propazine in the medium were all 100 mg·L -1 .

[0069] The WH-1 bacterial suspension in the exponential phase was inoculated into the high-salt LB medium supplemented with promethazine, simetropium, ametryn and propazine at a 5% inoculation rate and incubated at 150 r·min. -1 The samples were cultured on a shaker at 25°C for 24 hours. At 24 hours, samples were taken and sent to Shandong Aquatic Products Quality Inspection Center for detection of the residues of promethazine, simetropium, ametryn and propazine by gas chromatography-mass spectrometry to determine the degradation degree of promethazine, simetropium, ametryn and propazine.

[0070] The statistical results of the biodegradation rates of promethazine, simetropium, ametryn and propazine by strain WH-1 are shown in Figure 8 .Depend on Figure 8 It can be seen that strain WH-1 has a good degradation effect on the triazine herbicides promethazine, simetryn, ametryn and cypermethrin, and the 24h degradation rates are 63.3%, 53.7%, 46.9% and 48.6% respectively.

[0071] 7. Test the degradation effect of strain WH-1 on cypermethrin, simenon, ametryn and propazine in the marine environment.

[0072] 1. Cultivation of strain WH-1.

[0073] The strain WH-1 was inoculated into high-salt LB medium at a rate of 5% and then grown at 150 r·min. -1 The culture was carried out on a shaker at 25°C for 24 h to obtain a fermentation broth.

[0074] 2. Preparation of contaminated seawater samples and marine sediment samples.

[0075] Promethazine, simetropium, ametryn and propazine were added to the seawater at the same time and the concentration of each herbicide was 50 mg·L -1 , and obtain contaminated seawater samples.

[0076] Promethazine, simetropium, ametryn and propazine were added to the marine sediment at the same time, and the concentration of each herbicide was 50 mg·L -1 , to obtain contaminated marine sediment samples.

[0077] 3. Treat contaminated seawater and marine sediment samples with strain WH-1.

[0078] The fermentation broth of strain WH-1 was added to contaminated seawater samples and contaminated marine sediment samples, with an inoculation amount of 5% (v / v) and the samples were left to stand at 25°C for 7 days.

[0079] During the static treatment period, samples were taken every 24 hours to detect the concentrations of prometryn, simetropium, ametryn and propazine, and the biodegradation rates and degradation half-lives of prometryn, simetropium, ametryn and propazine were calculated.

[0080] 4. Results.

[0081] The statistical results of biodegradation rates of promethazine, simetropium, ametryn and propazine in contaminated seawater samples are shown in Fig. 9 .Depend on Fig. 9 It can be seen that after the contaminated seawater samples were treated with strain WH-1 for 7 days, the biodegradation rate of promethazine was 92.8%, and the degradation half-life was 2.99 days; the biodegradation rate of simenon was 88.3%, and the degradation half-life was 2.73 days; the biodegradation rate of ametaxycin was 77.4%, and the degradation half-life was 3.32 days; the biodegradation rate of cypermethrin was 83.9%, and the degradation half-life was 4.01 days.

[0082] The statistical results of biodegradation rates of promethazine, simetropium, ametryn and propazine in contaminated marine sediment samples are shown in Fig.10 .Depend on Fig.10It can be seen that after the contaminated marine sediment samples were treated with strain WH-1 for 7 days, the biodegradation rate of promethazine was 88.5%, and the degradation half-life was 3.01 days; the biodegradation rate of simenon was 83.3%, and the degradation half-life was 3.67 days; the biodegradation rate of ametaxycin was 80.9%, and the degradation half-life was 3.97 days; the biodegradation rate of cypermethrin was 79.4%, and the degradation half-life was 4.23 days.

[0083] The above results indicate that strain WH-1 has a highly efficient bioremediation effect on the marine environment (including seawater and marine sediments) contaminated by promethazine, simenon, ametryn and cypermethrin.

[0084] 8. Safety of strain WH-1 to marine animals and marine microalgae.

[0085] The strain WH-1 was inoculated into high-salt LB medium and incubated at 25°C and 150 r·min -1 The culture was shaken to the exponential phase at 5000 r / min. -1 Centrifuge for 5 minutes and collect the bacteria into sterile PBS buffer for later use.

[0086] 1. Safety of strain WH-1 to marine shellfish.

[0087] Four-horned clams (Mactra veneriformis) were from the Yellow River Delta mudflats and were temporarily cultured in natural seawater (water temperature 25±0.5℃) for 7 days. During the period of culture, they were fed with Closterium twice a day and the water was changed twice, with 2 / 3 of the water changed each time. The water was continuously aerated, feces was cleaned in time, and dead and unhealthy individuals were picked out. Feeding was stopped one day before the experiment, and healthy clams of uniform size were selected as experimental subjects. They were divided into experimental and control groups, with 3 parallels in each group and 30 clams in each parallel.

[0088] The strain WH-1 was added to the water of the experimental group to a final concentration of 10 7 CFU·mL -1 The same dose of sterile PBS buffer was added to the control group water. During the experiment, the fish were fed with Nitzschia closterium once every 24 hours and the water was changed once, with 1 / 2 of the water changed each time. The water was continuously aerated and the feces were cleaned in time. The experiment was conducted for 7 consecutive days.

[0089] Observation results: All the shellfish in each group were healthy and vigorous, with no mortality.

[0090] 2. Safety of strain WH-1 to marine copepods.

[0091] Eurytemora pacifica and Microsetellanorvegica Boeck were collected from the coastal waters of Yantai Economic and Technological Development Zone, Shandong Province. Natural seawater was filtered through a 0.45 μm mixed cellulose filter membrane and used. The water temperature was 25 ± 0.5 °C and the light-dark ratio was L: D = 12 h: 12 h. After acclimation and culture for 3 days, 300 healthy and active adults were selected for the experiment. The experimental group and the control group were set up, with 3 parallels in each group and 50 in each parallel, all of which were placed in 250 mL conical bottles.

[0092] The strain WH-1 was added to the water of the experimental group to a final concentration of 10 7 CFU·mL -1 The same dose of sterile PBS buffer was added to the control group water. Marine red yeast was fed once every 24 hours during the experiment, and the water was slightly aerated and observed for 3 consecutive days.

[0093] Observation results: Daphnia in each group survived normally and no death was observed.

[0094] 3. Safety of strain WH-1 to marine microalgae.

[0095] Nitzschia closterium f.minutissima was provided by the Algae Seed Room of Shandong Institute of Marine Resources and Environment. Natural seawater and f / 2 culture medium were sterilized and used for the culture of Nitzschia closterium f.minutissima. The water temperature was 25±0.5℃, the light intensity was 3000lx, and the light-dark ratio was L∶D =12h∶12h. After three generations of pre-culture, the cells were normal under microscopic examination and the experiment was carried out in the logarithmic growth phase. Experimental and control groups were set up, with 3 parallels in each group. 100mL of logarithmic growth phase algae solution was taken from each parallel and placed in a 250mL conical flask.

[0096] The strain WH-1 was added to the water of the experimental group to a final concentration of 10 7 CFU·mL -1 The same dose of sterile PBS buffer was added to the control group water and observed for 3 consecutive days. The number of algal cells was counted under a microscope using a hemocytometer.

[0097] Statistical results: There was no significant difference in the number of algal cells among the groups.

[0098] The above results show that strain WH-1 7 CFU·mL -1 Concentrations at and below are relatively safe for marine shellfish, marine copepods and marine microalgae.

[0099] 9. Preservation of bacterial strains.

[0100] The marine bacterium Stutzerimonas balearica WH-1 has been sent to the General Microbiology Center of China Microorganism Culture Collection Administration (CGMCC) for preservation. The preservation date is April 10, 2024, the preservation number is CGMCCNo.30298, and the preservation unit is Beijing, China.

[0101] It should be noted that the above embodiments are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the embodiments here. Any obvious changes or modifications derived from the technical solution of the present invention are still within the scope of protection of the present invention.

Claims

1. Marine Bacteria Stutzerimonas balearica WH-1 ​​is deposited in the General Microbiology Center of China Microorganism Culture Collection Administration, the deposit date is April 10, 2024, the deposit number is CGMCC No. 30298, and the depository address is Beijing, China.

2. Use of the marine bacterium Stutzerimonas balearica WH-1 according to claim 1 in degrading triazine herbicides, wherein the triazine herbicides include prometryn, simetryn, ametryn and propazine.

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