63 results about "Vibrio" patented technology

The invention discloses a fermentation method of recombinant bacillus subtilis for expressing vibrio parahaemolyticus outer membrane protein, which comprises the following steps: inoculating a recombinant bacillus subtilis strain into a liquid culture medium for activation and amplification to obtain a seed solution; transferring the seed solution into a fermentation tank according to the inoculum size of 5%-10%, controlling the temperature to be 35-37 DEG C and the pH to be 6.8-7.2, introducing sterile air and stirring, and monitoring the thallus concentration OD600 value in real time; when the OD600 value reaches 35-38, 10% of an inducer is added for pre-induction; when the OD600 value reaches 40-45, the remaining 90% of the inducer is added for main induction, and the real-time dissolved oxygen value is collected; when the real-time dissolved oxygen value is continuously higher than a first preset threshold value, the flow acceleration rate of the inducer is increased, the fermentation temperature is increased at the same time or step by step, and the increase amplitude of the dissolved oxygen value is in positive correlation with the flow acceleration rate and the temperature increase amplitude; when the OD600 value is stabilized in a preset interval, it is judged that fermentation is completed, and the recombinant bacillus subtilis thalli are obtained. The yield and quality of the vibrio parahaemolyticus outer membrane protein can be effectively improved.

The invention discloses saccharomyces boulardii, a culture and a preparation method and application of the saccharomyces boulardii. The preservation number of the strain is CCTCC (China Center for Type Culture Collection) NO: M 20252633. The preparation method comprises the following steps: preparing saccharified liquid by taking white spirit vinasse or brewer's grains as a main raw material and adopting a high-temperature alkali treatment and composite enzymolysis process, inoculating strains for liquid-state high-density fermentation, carrying out solid-liquid separation on fermentation liquor, taking a liquid phase, and carrying out spray drying. According to the method, high-value utilization of the waste vinasse is realized, and the production cost is remarkably reduced. The obtained culture is rich in viable bacteria and active small peptides, and has the characteristics of strong tolerance, wide antibacterial spectrum and the like. As a feed additive, the feed additive can effectively reduce the diarrhea rate of piglets, inhibit clostridium perfringens and prawn vibrios of broilers, and improve the oxidation resistance and production performance of animals.

The invention belongs to the technical field of gene engineering, and particularly relates to ALFPm3 modified antibacterial peptide, a molecular design and construction method and application of the ALFPm3 modified antibacterial peptide, and the amino acid sequence of the ALFPm3 modified antibacterial peptide is selected from any one of SEQ ID NO: 1-SEQ ID NO: 7. Analysis and design are carried out by combining the structure and action site of vibrio parahaemolyticus and the molecular structure and function relationship of the antibacterial peptide ALFPm3 as a basic template, the antibacterial activity of the antibacterial peptide ALFPm3 is improved, and other biological activities such as hemolysis are reduced.

The invention discloses a preparation method of a boiling antigen for vibrio parahaemolyticus serum agglutination. The preparation method comprises the following steps: selecting common serotype vibrio parahaemolyticus in monitoring for resuscitation; scraping a ring of placenta by using 10 mu L of an inoculating loop, dissolving the placenta in 1 mL of normal saline to prepare a bacterial suspension, and preparing 3 tubes of bacterial suspensions from each strain; boiling the bacterial suspension in boiling water for 1 hour, 45 minutes and 30 minutes respectively; and after boiling, centrifuging at 10000 rpm for 10 minutes, discarding the supernate, and reserving the precipitate as a boiling antigen for serum agglutination. The result shows that the agglutination accuracy after boiling for 1 hour is 100%, and the agglutination degree is 2 + or above; and no significant difference exists between 45 minutes of boiling and 1 hour of boiling, and no significant difference exists between 30 minutes of boiling. Compared with a high-pressure method, the method has the advantages that the operation time is shortened by 2-3 hours, special equipment certificates are not needed, and the method is suitable for daily detection and food poisoning traceability.

The invention provides a breeding method suitable for breeding litopenaeus vannamei in saline-alkali soil, and relates to the technical field of aquaculture. According to the breeding method suitable for breeding the litopenaeus vannamei in the saline-alkali soil, the proportion of Ca < 2 + > to Mg < 2 + > to K < + > in a water body is optimized to be 2.8: 1: 0.3 by customizing a compound ion regulation and control solution, SO4 < 2-> / Cl <-> is controlled to be 0.14-0.8, and the pH is stabilized to be 8.2-8.8 in combination with a citric acid-sodium citrate buffer system; a slow-medium-fast segmented domestication strategy is adopted to adapt to different development stages of the fries; ethanol clostridium protein (CAP) is added into the feed to be combined with compound probiotics, so that immune metabolism regulation and control are enhanced. Experiments prove that according to the method, the survival rate of the litopenaeus vannamei seedlings reaches 86.3% + / -2.1%, the culture period is shortened by 12-15 days, the hepatopancreas SOD activity is improved by 42.6%, the vibrio inhibition rate reaches 78.5%, and the method is remarkably superior to the prior art. The method does not need large-scale pond transformation, adapts to different types of saline-alkali soil water bodies, realizes efficient green culture, and has important application value.

The present application belongs to the field of microbial culture, and particularly relates to a culture medium for reducing expression of surface polysaccharide of Vibrio parahaemolyticus. The formula of the polysaccharide low-expression culture medium is selected from specific proportion of nutritional components and specific conditions for inhibiting polysaccharide expression, so that the expression amount of surface lipopolysaccharide and capsule polysaccharide of Vibrio parahaemolyticus after the culture medium is increased is lower than the expression amount of polysaccharide of Vibrio parahaemolyticus after normal culture, the expression of surface lipopolysaccharide and capsule polysaccharide can be inhibited to a certain extent, the surface of the bacterial body can better expose outer membrane protein, and the immunodetection of Vibrio parahaemolyticus is facilitated. The present application provides a technical basis for developing a complete immunodetection method of Vibrio parahaemolyticus.

The invention discloses a vibrio canetinii bacteriophage capable of being split across species and application, the bacteriophage is a vibrio canetinii bacteriophage CP2 which is preserved in the China Center for Type Culture Collection with the preservation number of CCTCCM20251108, and the vibrio canetinii bacteriophage CP2 is preserved in the China Center for Type Culture Collection. The vibrio cantoniensis bacteriophage CP2 is a virulent bacteriophage separated from the nature, is free of genetic modification, has high safety and strong application potential, has an optimal infection complex number of 1: 10000, has a fermentation titer of 3.5 * 10 < pfu > / mL after 12 h, can rapidly split vibrio cantoniensis, has a recognition rate of 96.7% to 180 vibrio cantoniensis strains and a splitting rate of over 96%, and can be used for preparing the vibrio cantoniensis bacteriophage CP2. The genome does not contain toxicity and bad genes, the biological safety is high, the bacteriophage is excellent in environmental adaptability, stable in activity when the pH value is 6-8, high in storage stability at 4-25 DEG C, capable of being stored for 12 months at 4 DEG C, capable of stably surviving at room temperature, tolerant to a common chemical agent povidone-iodine for aquatic products, and suitable for various breeding scenes. Meanwhile, the cracking spectrum is wide, and the cross-species capability is realized.

The application discloses a bocachito Nat10 antibacterial peptide, a coding sequence and use and a preparation method thereof, and relates to a method based on multiomics, a biological big data based on multiomics data of bocachito, screening and identifying an antibacterial peptide precursor gene sequence, and obtaining an amino acid sequence of the bocachito Nat10 antibacterial peptide through translation design, as shown in SEQ ID NO: 3. Through activity simulation prediction and in-vitro experiment verification, the bocachito Nat10 antibacterial peptide shows inhibitory effects on the growth activities of Streptococcus agalactiae, Salmonella enteritidis, Staphylococcus aureus, Vibrio anguillarum and Escherichia coli, especially on Staphylococcus aureus, and shows the best antibacterial effect at a concentration of 2.5 micromoles per liter. The bocachito Nat10 antibacterial peptide can be used for preparing various bactericidal preparations, including bacteriostatic agents, medicines or additives, and has good practical value and social ecological benefits.

The application discloses a colorimetric-SERS dual-mode detection and photothermal sterilization method for specifically detecting Vibrio parahaemolyticus and application thereof, and belongs to the technical field of food safety biology. The application takes Vibrio parahaemolyticus as a target, and prepares a multifunctional magnetic composite nanomaterial through layer-by-layer assembly. Firstly, the superparamagnetic separation performance of the magnetic composite nanomaterial is combined with magnetic chromatography to achieve the effect of rapidly separating bacteria from a complex food matrix. Secondly, the colorimetric and SERS sensing signals of the magnetic composite nanomaterial are used to quantitatively detect bacteria in a short time, high precision and high stability in a dual-mode. Finally, the photothermal performance of the magnetic composite nanomaterial is used to kill the detected bacteria by photothermal sterilization, so that the hazard control at the back end of detection is completed.

This invention relates to the field of aquatic compound feed technology, specifically to a special feed for mullet, silver carp, and golden carp cultured in saline-alkali land in Northwest China. The feed is characterized by being composed of the following raw materials by weight percentage: 10%–14% alfalfa meal, 16%–22% soybean meal, 16%–22% corn meal, 5%–7% molasses, 1%–3% yeast powder, 2%–5% lactic acid bacteria preparation, 2%–5% premixed feed for aquatic life in saline-alkali land in Northwest China, 1%–4% fish oil, and 1%–5% vegetable oil. This invention solves the problems of low survival rate, high feed conversion ratio, easy antagonistic inactivation of probiotics, fish oil oxidation, poor water resistance of pellets, and insufficient regional adaptability of traditional feeds. Compared with commercially available ordinary marine fish feeds, the survival rate of juvenile fish is increased by 15% to 30%, the feed conversion ratio is reduced by 10% to 20%, the Vibrio inhibition rate is ≥80%, the power consumption per ton of feed is reduced by 25% to 35%, and the raw material cost is reduced by 30% to 45%. It is suitable for large-scale aquaculture in saline-alkali land in Northwest China and has important value for improving the quality and efficiency of fisheries, ecological restoration, and rural revitalization.

The invention belongs to the technical field of biology, and discloses a polypeptide derived from a deep sea ecological environment, an application of the polypeptide in preparation of an antibacterial preparation and an antibacterial drug. According to the application of the polypeptide disclosed by the invention in the preparation of the antibacterial preparation, the polypeptide comprises one or more of amino acid fragments with sequences shown as SEQ ID NO: 1-9, the compound has good bacteriostatic or bactericidal activity on one or more of escherichia coli, halomonas aeruginosa, acinetobacter picoteri, staphylococcus aureus, linear preristeria, klebsiella pneumoniae and vibrio parahaemolyticus, and has extremely low toxicity on mammalian cells under an effective concentration. The compound has excellent bacteriostatic activity, bacteriostatic broad-spectrum property and biocompatibility, and has very excellent application prospects in multiple fields such as food preservation, agricultural disease prevention and control, feed additives and the like.

The invention belongs to the technical field of aquaculture, and particularly relates to a greenhouse culture method for soft-shelled turtles, which comprises the following steps: step S1: carrying out steady-state water culture on culture water; and S2, setting the breeding temperature and humidity, and carrying out gradient fry throwing breeding. According to the method, the number of vibrios in the culture water body can be effectively reduced by performing steady-state culture on the culture water body, and then the mortality rate of the young turtles can be effectively reduced by performing gradient-temperature young turtle throwing culture on the turtles.

The invention relates to a primer probe group, a multiplex fluorescent quantitative PCR method and a kit for simultaneously detecting six pathogenic bacteria, and belongs to the technical field of molecular biology, the primer probe group comprises primer sequences and probe sequences shown in SEQ ID No.1-18 in a table 1; the 5'end of each probe sequence is modified with a reporter group, and the 3 'end of each probe sequence is modified with a quenching group; the reporter group is Cy5, FAM and VIC, and the quenching group is Eclipse. The invention provides a method for simultaneously detecting six pathogenic bacteria including vibrio parahaemolyticus, salmonella, staphylococcus aureus, escherichia coli O157: H7, listeria monocytogenes and shigella in the same reaction system by combining a multiple real-time fluorescent quantitative PCR (Polymerase Chain Reaction) technology. The multiplex real-time fluorescent quantitative PCR kit provided by the invention is used for detecting the six pathogenic bacteria, can improve the detection sensitivity and specificity, greatly improves the detection efficiency, and overcomes the defects of complex steps, long detection period and incapability of adapting to large-scale rapid detection in the conventional detection method.

The invention provides application of an antibacterial peptide targeting a vibrio parahaemolyticus outer membrane protein LptD, and belongs to the technical field of antibacterial peptides. The amino acid sequence of the antibacterial peptide targeting the vibrio parahaemolyticus outer membrane protein LptD provided by the invention is as shown in SEQ ID NO. 1. The antibacterial peptide provided by the invention can specifically inhibit vibrio parahaemolyticus, and the integrity of an outer membrane is destroyed by combining a beta-taco structural domain of LptD protein, so that cellular contents are leaked. In a ready-to-eat salmon model, the load of artificially inoculated vibrio parahaemolyticus can be reduced by 1.51 log CFU / mL by soaking 64 micrograms / mL of the antibacterial peptide disclosed by the invention for 4 hours, and meanwhile, the regeneration of a biofilm in a storage period is remarkably inhibited. Safety experiments prove that the antibacterial peptide provided by the invention has the advantage of high safety.

The invention provides application of protocatechuic acid in regulating intestinal flora of procambarus clarkii and flavor amino acid composition in muscle of the procambarus clarkii, and belongs to the technical field of development of aquatic feed additives. It is found that the protocatechuic acid can reduce the abundance of Vibrionaceae in the intestinal tract level of the procambarus clarkii, improve the abundance of Rhodobacteroceae, Lactobacillus and Bacillus, reduce the abundance of Vibrio in the intestinal tract level of the procambarus clarkii, and improve the abundance of Halocynthiibacter and Ruegeria, so that the composition of flavor amino acids in the muscles of the procambarus clarkii is improved. The invention further provides a procambarus clarkii feed and application thereof in procambarus clarkii culture, the content of flavor amino acids in procambarus clarkii can be effectively increased, the muscle quality of procambarus clarkii is improved, the cost is low, and the culture method is simple.

The present application provides a method for improving the tolerance of corals to Vibrio coralliius, which comprises the following steps: first, culturing healthy Echinomorpha crassior and Acropora humilis; then, inoculating Vibrio coralliius to the two corals to screen out the coral, Acropora humilis, which is resistant to Vibrio coralliius and the coral, Echinomorpha crassior, which is susceptible to Vibrio coralliius; taking the screened Acropora humilis as a donor to culture microbial liquid; inoculating the microbial liquid to the screened Echinomorpha crassior, so as to improve the tolerance of the Echinomorpha crassior to Vibrio coralliius. The present application has the advantages of simple operation, safety and reliability, high efficiency of coral mixed liquid extraction and high microbial activity. The coral resistant to Vibrio coralliius is taken as a donor to prepare a mixed liquid, and the coral susceptible to Vibrio coralliius is treated to improve its tolerance. The method has low ecological side effects, can quickly and effectively improve the tolerance of the coral susceptible to Vibrio coralliius, and has a wide application prospect.

The present application provides a composite sonosensitizer and its bacterial target delivery system BPT-ICG@Bd capable of treating pseudomonas aeruginosa biofilm related infection, wherein the composite sonosensitizer (BPT-ICG) is composed of inorganic sonosensitizer (BPT) and organic sonosensitizer (ICG), Bd is natural gram-negative bacteria predator Bdellovibrio, the composite sonosensitizer (BPT-ICG) is modified to the surface of Bdellovibrio (Bd) by polydopamine to form BPT-ICG@Bd. The high-speed movement characteristics of Bdellovibrio predator gram-negative bacteria are used to destroy the biofilm structure, invade bacteria, and at the same time, the composite sonosensitizer is triggered to produce a large amount of active oxygen by applying ultrasound, so as to quickly remove the biofilm and bacteria, and be used for biofilm related lung infection and bone infection.

The application discloses five kinds of high-throughput detection primer groups, kits and application of LAMP method for foodborne pathogenic bacteria, and belongs to the technical field of foodborne pathogenic bacteria detection. The primer groups correspond to five kinds of bacteria, including Salmonella, Vibrio parahaemolyticus, Listeria monocytogenes, Escherichia coli O157:H7 and Staphylococcus aureus, and the nucleotide sequences of the primers are SEQ ID No. 1-30. The complete process detection can be completed at 62 DEG C constant temperature for 45 minutes, the result does not need complex instruments, the positive gray and the negative purple are judged by naked eyes, and the operation is simple. The detection sensitivity reaches 1-75 copies / reaction, the artificially contaminated aquatic product sample does not need to be subjected to bacterial enrichment, is subjected to simple lysis and enrichment, has strong specificity and no cross reaction. The anti-interference ability is outstanding, the complex matrix of aquatic products is adapted, the detection coincidence rate is high, the cost is low, only a conventional constant temperature device is needed, and the application is suitable for multiple scenes, such as detection institutions, food enterprises and on-site law enforcement on-site detection of primary food, agriculture, disease control, customs and the like, and provides an efficient and economical technical means for aquatic product safety control.

The invention discloses a method for improving the expression intensity of a bacillus subtilis self-induced expression system, and belongs to the technical field of genetic engineering and microbial engineering. According to the bacillus subtilis recombinant bacteria disclosed by the invention, pBLSI4310SP35UP3A containing Vibrio fischeri LuxI / R type QS is taken as a carrier, bacillus subtilis WB600 is taken as an expression host, and raw starch alpha-amylase derived from marine bacillus pincare sp.ZY is taken as a target protein. The activity of the bacillus subtilis recombinant extracellular AmyZ1 obtained by transforming a-35 region of a response module promoter RPlug < x > IR6 is 435 U / mL, which is 1.47 times of that of a control group, and the activity of the bacillus subtilis recombinant extracellular AmyZ1 is further improved to 926 U / mL, which is 3.14 times of that of the original control group, by directionally transforming an amino acid sequence of LuxR in the induction module, so that the activity of the bacillus subtilis recombinant extracellular AmyZ1 is improved to 926 U / mL, which is 3.14 times of that of the original control group. The self-induction expression intensity of the Vibrio fischeri LuxI / R type QS in the bacillus subtilis is obviously improved, and the self-induction expression intensity of the Vibrio fischeri LuxI / R type QS in the bacillus subtilis is obviously improved.

The invention discloses a spore surface display vibrio parahaemolyticus VPOmpK-MeL recombinant bacillus subtilis as well as a construction method and application thereof. According to the recombinant bacillus subtilis, on the basis of an integrated plasmid pDG364, a recombinant vector which takes spore capsid protein CotY as anchoring protein and displays a fusion fragment of a VPOmpK antigen and bee venom peptide Melittin on the surface is constructed, recombinant protein is converted into a wild type bacillus subtilis 168 gene, and the obtained recombinant spore expressing OmpK-MeL protein has genetic stability; the bacterium directly displays antigen protein on the surface of a spore, does not need to be broken, and can be directly mixed with materials or drink water to immunize animals, so that the problems of difficult protein purification, tedious injection immunization process and the like are avoided; the spores have good stress resistance, so that the spores are easy to store and transport, and the cost is remarkably reduced; the strain can induce specific immune response, and the fusion expressed MeL plays an excellent role in enhancing immunity, so that a new way is provided for prevention and treatment of VP, and the strain can be applied to development of commercial vaccines.

This invention relates to the field of microbial technology, specifically disclosing a thermoresistant Aeromonas verrucosa phage, its screening method, and its applications. The phage is deposited under CGMCC No. 47009. This phage belongs to the Myocaudidae family and exhibits significant heat resistance, maintaining a titer of 10 even after treatment at 70°C for 60 minutes. ^ 8 This bacteriophage exhibits a PFU / mL concentration above [amount missing] and can withstand the high temperatures of feed pelleting. It displays broad-spectrum lytic activity against *Aeromonas vesiculosus* and can cross-lyze *Aeromonas guinea pig* and *Aeromonas hydrophila*. This invention also provides a rapid screening method for this heat-resistant bacteriophage. Through a cycle of instantaneous heat treatment at 70°C followed by rapid cooling in an ice bath, genetically stable bacteriophages can be obtained within 5 days, solving the problems of long cycles and poor stability associated with traditional acclimatization methods. The bacteriophage and composition of this invention can be used to prepare veterinary drugs and disinfectants for the prevention and treatment of aquatic aeromonas diseases, showing broad application prospects.

Primers and primer sets for amplification of Vibrio parahaemolyticus DNA and methods of detecting Vibrio parahaemolyticus using the primers and primer sets.

The invention relates to a lyase and a coding gene thereof, and application of the lyase in lysing bacteria. The bacteriophage capable of specifically splitting the vibrio parahaemolyticus is obtained through separation and purification, lyase is cloned from a genome of the bacteriophage, and after the lyase is subjected to prokaryotic expression and purification, the obtained protein shows the characteristics of the cleavable vibrio parahaemolyticus. The lyase disclosed by the invention has an obvious antibacterial effect on vibrio parahaemolyticus under the assistance of a permeable membrane agent, so that the lyase has a potential application value in the aspect of controlling pollution of the vibrio parahaemolyticus.

The invention discloses an indoor cultivation method for increasing the survival rate of larvae and juveniles of horse mackerels, and relates to the technical field of aquaculture. Pretreated rotifers, shadberry fruit extracts and 2, 4 '-dihydroxychalcone are added in the early larva fish breeding stage and the later larva fish breeding stage, active ingredients such as gulcomannan, proline, chlorogenic acid and potentilla discolor extracts are added in the juvenile fish breeding stage, and meanwhile environmental factors such as illumination and sound wave stimulation are regulated and controlled, so that the juvenile fish breeding efficiency is improved. The survival rate of the horse mackerels and the capability of resisting infection of lactococcus gasseri and vibrio anguillarum can be effectively improved, the investment of the breeding cost is reduced, and the used baits are simple, easy to obtain and simple to prepare.

The application discloses a shrimp intestinal tract Tenacibaculum lutimaris strain and application of the shrimp intestinal tract Tenacibaculum lutimaris strain in shrimp culture, and has the characteristics that the strain is BG12 strain, is classified and named as Tenacibaculum lutimaris, is preserved in the China General Microbiological Culture Collection Center on July 8, 2022, and has a preservation number of CGMCC No. 25267, the application of the shrimp intestinal tract Tenacibaculum lutimaris strain in preparation of a Vibrio parahaemolyticus inhibitor and in preparation of a probiotic additive for shrimp culture, and the advantages are that the shrimp intestinal tract Tenacibaculum lutimaris strain has amylase and cellulase activities, and can improve the survival rate of shrimp culture and the anti-invasion ability of shrimp culture to Vibrio parahaemolyticus.

The application belongs to the technical field of aquaculture, and particularly relates to a method for improving the attachment rate and disease resistance of long oyster (Crassostrea gigas) nauplii and application thereof. The method is that early nauplii of the long oyster are soaked in filtered seawater containing a certain dose of glutathione. Compared with a control group without adding glutathione, the growth and development speed of the long oyster nauplii soaked in the glutathione is accelerated, the attachment rate is significantly improved, the lysozyme activity is enhanced, and the ability to resist vibrio is significantly increased. The application has a significant effect on reducing the mortality of the long oyster nauplii in the attachment metamorphosis process and improving the attachment metamorphosis rate, and can be used as an immune enhancer for the attachment metamorphosis stage of the long oyster and applied to seed production.

The present application relates to the technical field of aquatic pathogenic bacteria culture, and particularly relates to a preparation method of a freshwater vibrio high-efficiency culture composite medium containing a nucleotide compound.A freshwater vibrio high-efficiency culture composite medium containing a nucleotide compound, in terms of weight parts, includes the following functional components: 2000-5000 parts of a carbon source, 1500-3000 parts of a nitrogen source, 225-405 parts of a precursor substance, 65-125 parts of an amino acid, 55-110 parts of an energy system, 650-1300 parts of an ion regulator, 35-85 parts of a membrane stabilizer, and 10-20 parts of an antioxidant.The present application solves the technical problem that the prior art lacks a culture method that can effectively promote the growth of freshwater vibrio and ensure the motility activity of the freshwater vibrio.Through reasonable formulation and process design, the present application breaks through the bottleneck of the existing freshwater vibrio culture technology, provides support for the research, targeted prevention and control, and efficient detection method establishment of aquatic pathogenic bacteria, and has a significant application prospect.

The utility model discloses a water quality toxicity on-line monitoring device which comprises a solid-liquid separation mechanism, a treatment mechanism and a monitoring mechanism, an inlet of the solid-liquid separation mechanism is communicated with a water sample source, and the pretreatment mechanism is used for carrying out solid-liquid separation on a water sample and extracting a liquid part; the treatment mechanism comprises a chronic toxicity test treatment mechanism and an acute toxicity test treatment mechanism, and the chronic toxicity test treatment mechanism and the acute toxicity test treatment mechanism are respectively communicated with a liquid outlet of the solid-liquid separation mechanism; the detection mechanism is respectively communicated with outlets of the toxicity chronic inspection and treatment mechanism and the toxicity acute inspection and treatment mechanism, and the monitoring mechanism is used for adding vibrio qinghaiensis bacterial liquid into water samples treated by the toxicity chronic inspection and treatment mechanism and the toxicity acute inspection and treatment mechanism and monitoring the luminous intensity of the water samples. The method can solve the problems of low rationality and accuracy of the existing on-line monitoring of the water quality toxicity of the fresh water.

The invention discloses a bimetallic nano-enzyme as well as a preparation method and application thereof, and relates to the technical field of biological detection. The bimetallic nano-enzyme is a DNA-Ag / Pt bimetallic nano-enzyme material prepared on the basis of a specific DNA template sequence or containing the specific DNA template sequence, and can be combined with a double-emission ratio type silver nano-cluster to be used for double-signal detection of vibrio parahaemolyticus. The bimetallic nano-enzyme has peroxidase-like activity, the enzyme activity efficiency is adjustable, and the bimetallic nano-enzyme can be used for double-signal detection of vibrio parahaemolyticus. Compared with the prior art, the color development absorbance of the bimetallic nano-enzyme provided by the invention is improved by about 15%, the lowest detection limit of a colorimetric detection method is 10 CFU / mL, and the lowest detection limit of a fluorescence detection method is 1 CFU / mL; the method has no cross reaction on staphylococcus aureus, escherichia coli, pseudomonas aeruginosa, salmonella, vibrio vulnificus and the like, and is suitable for on-site rapid screening, visual interpretation and semi-quantitative detection of scenes such as water samples and marine products.