67 results about "Pyridoxal" patented technology

The present technical solution discloses a method for producing fermented fish sausages and fermented fish sausages that improve the distinctive flavor of the sausage. The present invention adds 5-pyridoxal phosphate, which is a cofactor that catalyzes the transaminase reaction and can catalyze the leucine in the fish protein to produce α-ketoisocaproic acid, thereby increasing the content of 3-methylbutyraldehyde; by adding a composite fermentation agent, Lactococcus lactis subspecies cremoris contains transaminase, which promotes the catabolism of leucine and isoleucine to produce 3-methylbutyraldehyde and 2-methylbutyraldehyde; Lactobacillus sakei contains α-ketoacid decarboxylase, which promotes the catabolism of leucine to produce 3-methylbutyraldehyde. The present technical solution can improve the fermentation efficiency of naturally fermented sausages and regulate the flavor of the fermented sausages, so that the fermented fish sausages have a rich caramelized aroma, fruity flavor, and bacon flavor, and a delicate, smooth, and elastic taste.

The present application relates to a pyridoxal kinase mutant, a recombinant expression vector and a microbial cell and their applications, and belongs to the technical field of biological catalysis. In order to solve the problem of low product concentration in existing enzyme catalysis, a pyridoxal kinase mutant is provided, the amino acid sequence is selected from the amino acid sequence shown in SEQ ID NO. 1, the lysine at position 229 is mutated to alanine, phenylalanine, methionine, arginine, threonine, histidine, serine, tyrosine, valine, leucine, isoleucine, proline, asparagine, aspartic acid or glutamic acid; the pyridoxal kinase mutant is used for catalyzing pyridoxal to synthesize pyridoxal phosphate, and a recombinant expression vector and a microbial cell can be further formed. The present application has good enzyme activity, high product conversion rate, high concentration of pyridoxal phosphate obtained, and the concentration of the product catalyzed by the wild-type pyridoxal kinase to phosphorylate pyridoxal is obviously improved.

The invention relates to a pyridoxal kinase mutant, a recombinant expression vector, a microbial cell and application thereof, and belongs to the technical field of biological catalysis. In order to solve the problem of low concentration of the existing enzyme catalysis product, the invention provides the pyridoxal kinase mutant. The amino acid sequence is selected from lysine at the 229 site of the amino acid sequence as shown in SEQ ID NO.1, and the lysine at the 229 site of the amino acid sequence as shown in SEQ ID NO.1 is mutated into alanine, phenylalanine, methionine, arginine, threonine, histidine, serine, tyrosine, valine, leucine, isoleucine, proline, asparagine, asparaginic acid or glutamic acid; the pyridoxal kinase mutant is used for catalyzing pyridoxal to synthesize pyridoxal phosphate, and recombinant expression vectors, microbial cells and the like can be further formed. The pyridoxal phosphate has good enzyme activity and high product conversion rate, the concentration of the obtained pyridoxal phosphate is high, and the concentration of a product obtained by catalyzing phosphorylation of pyridoxal through the pyridoxal phosphate kinase is obviously improved compared with that of a product obtained by catalyzing phosphorylation of pyridoxal through wild type pyridoxal kinase.

The invention belongs to the technical field of industrial silane preparation, and provides a natural silane rotor and a preparation method and application thereof.The preparation method comprises the steps that a pyridoxal phosphate solution and a 4-amino ethyl cinnamate solution are mixed and then react to obtain pyridoxal phosphate cinnamyl ester; and mixing the pyridoxal phosphate cinnamyl ester solution and the amino silane solution, and reacting to obtain the natural silane rotor. The silane rotor has a good conjugated structure, is stable in chemical structure, can be stored for a long time, is good in light stability, and is not liable to cause a photobleaching phenomenon. Besides, conjugated single and double bonds capable of freely rotating exist in the molecular structure, a typical flexible intramolecular rotation characteristic is presented, the conjugated structure can freely rotate in a dilute solution, a surface sightseeing signal is weak, the free rotation phenomenon is limited in a thick solution, the surface sightseeing signal is strong, and the surface sightseeing signal is strong. Therefore, the device can be used as a molecular tool for monitoring the change of the thin consistency of the silane, and can provide real-time, lossless and visual detection support for the development of a silane modulation process.

The invention discloses a method for efficiently producing pyridoxal phosphate based on a three-enzyme cascade reaction and a recombinant strain, and belongs to the technical field of biological engineering. The recombinant escherichia coli for co-expressing the pyridoxine phosphate phosphatase mutant, the pyridoxine phosphate oxidase and the hydrogen peroxide decomposing enzyme is constructed, three-enzyme synergy is realized by optimizing the copy number of a carrier, and the catalytic efficiency of a recombinant strain as a cell catalyst is improved. The invention further provides a one-pot method for preparing pyridoxal phosphate, the production cost is reduced, an efficient, green and economical biosynthesis path is provided for industrial production of PLP, and the method can be widely applied to the fields of food, medicine and the like and has important industrial value and application prospects.

The invention relates to the technical field of genetic engineering, in particular to a recombinant microorganism and application thereof in preparation of glycine. The application comprises the following steps: producing glycine by adopting the recombinant microorganism; the recombinant microorganism comprises an enzyme combination and / or a nucleic acid molecule combination. The enzyme combination comprises threonine aldolase, ethanol dehydrogenase and isopropanol dehydrogenase; the threonine aldolase comprises an amino acid sequence as shown in SEQ ID NO. 1. The nucleic acid molecule combination is used for encoding the enzyme combination. According to the invention, threonine aldolase, ethanol dehydrogenase and isopropanol dehydrogenase are converted into microorganisms, and the constructed recombinant microorganisms can be used for decomposing threonine to produce glycine; and a specific system formed by specific isopropanol dehydrogenase, ethanol dehydrogenase and isopropanol dehydrogenase can also have a relatively high conversion rate under the condition of no addition of pyridoxal phosphate (PLP), and has important significance and economic value.

The invention relates to a pyridoxal phosphate (PLP) synthesis method based on cascade biological catalysis and capable of realizing ATP autonomous regeneration. The method comprises the following steps: constructing engineering bacteria for co-expressing pyridoxal phosphate kinase (PdxK) and polyphosphate kinase (PPK) to prepare a whole-cell catalyst or a crude enzyme solution; under the condition that ATP does not need to be exogenously added, pyridoxal, ADP and polyphosphate serve as substrates, cascade reaction is carried out under the action of a catalyst, ATP is regenerated in situ, and PLP synthesis is driven. A wild enzyme system is adopted, and the yield of PLP exceeds 95% within 4 hours of reaction; after PdxK mutation optimization, the reaction time is shortened to about 2 hours, and conversion can be completed. According to the invention, a polyphosphate-driven ATP regeneration system is coupled with PLP biosynthesis, so that the cofactor cost is remarkably reduced, a feasible technical path is provided for industrial biological manufacturing of PLP, and the application of polyphosphate in cyclic regeneration of cofactors is expanded.

This invention relates to a pyridoxal phosphate-responsive biosensor and its application, belonging to the field of synthetic biology biosensor technology. This invention is the first to discover and identify the relationship between pyridoxal phosphate and Cgl1185-P. cgl2838 The transcriptional regulation and response relationship between these factors was investigated, and this relationship was used as the basis for constructing a biosensor responsive to pyridoxal. The transcription factor regulatory system Cgl1185-P derived from Corynebacterium glutamicum was used. cgl2838 A biosensor for the specific detection of pyridoxal phosphate was constructed by assembling a reporter gene as the main component onto a plasmid, enabling effective detection of pyridoxal phosphate concentrations in intracellular or culture environments. This biosensor possesses advantages such as clear structure, high sensitivity, and good host adaptability, and can be used for fermentation process monitoring, cofactor metabolism research, and screening of relevant strains, showing promising application prospects in the fields of cofactor concentration monitoring and metabolic regulation.

The invention relates to the field of food biotechnology and fermentation engineering, and discloses lipid-lowering health-preserving vinegar capable of strengthening an amino acid metabolic pathway and a preparation process thereof, and the lipid-lowering health-preserving vinegar capable of strengthening the amino acid metabolic pathway is prepared by fermenting soybean protein isolate, silkworm chrysalis protein powder, broken rice, oat bran, a metabolism anchoring regulation composite emulsion and a plant extract. According to the metabolism anchoring regulation composite emulsion, carrier oligopeptide, pyridoxal-5-phosphoric acid and metal ions are utilized to construct a coordination system, and the microbial amino acid metabolism flow direction is directionally regulated. The preparation process is completed by adopting lactobacillus plantarum and acetobacter pasteurianus through anaerobic-aerobic variable-temperature variable-dissolved-oxygen coupling fermentation. Through a metabolic network intervention strategy, the enrichment efficiency of gamma-aminobutyric acid and hydrophobic active oligopeptide in the finished product is remarkably improved, and the flavor of the product is improved, so that the table vinegar is endowed with stronger auxiliary lipid-lowering and pressure-lowering effects.

The invention provides a composition comprising a Plasmodium species multimeric protein capable of forming a nanoparticle and at least one antigen of interest, wherein the multimeric protein comprises a monomer chosen from Plasmodium species pyridoxal 5'-phosphate synthase (PLP), chaperone 60 protein (Cpn60), and caseinolytic protease (Clp). In embodiments, the invention provides the composition wherein the monomers assemble to form a multimeric nanoparticle and / or which comprises an adjuvant. The invention further provides a nucleic acid encoding the multimeric protein and the at least one antigen of interest, E. coli comprising the nucleic acid, and the use of such in a method for producing the inventive multimeric protein and the at least one antigen of interest. Also provided are a method and use of the inventive multimeric protein and the at least one antigen of interest for immunizing a subject against Plasmodium species.

The invention relates to a biosynthesis method of pyridoxal phosphate or pyridoxine phosphate, and belongs to the technical field of biosynthesis. In order to solve the existing problem of serious environmental pollution, the invention provides a biosynthesis method of pyridoxal phosphate or pyridoxine phosphate, which comprises the following steps: in the presence of polyphosphate, magnesium salt, ATP (adenosine triphosphate), pyridoxal kinase and polyphosphate kinase, performing phosphorylation reaction on pyridoxal or pyridoxine and acid salts thereof, thereby obtaining the pyridoxal phosphate or pyridoxine phosphate. The temperature of the phosphorylation reaction is controlled to be 30-38 DEG C, after the reaction is finished, protein separation is conducted on reaction liquid, mother liquor is separated, the compound pyridoxal phosphate or pyridoxine phosphate shown in the formula I is obtained, and the mother liquor is recycled and reused. According to the method, a large amount of ammonium acetophosphate does not need to be additionally added, operation is simpler, mother liquor can be recycled, a large amount of waste water is prevented from being discharged, environment friendliness is better achieved, and the yield is high.

This invention relates to the field of biomaterial preparation technology, and in particular to a morphology-controllable mesoporous hydroxyapatite nanosphere, its preparation method, and its applications. The preparation method includes: S1, mixing an aqueous solution of pyridoxal phosphate with an aqueous solution of calcium chloride, adjusting the pH of the mixed solution to 7-11 to obtain a precursor solution; S2, placing the precursor solution in a microwave reactor for reaction to obtain mesoporous hydroxyapatite nanospheres. The preparation method provided by this invention is simple, the reaction conditions are easily controlled, and it is highly safe and reliable. It enables precise control of the morphology and particle size of the hydroxyapatite microspheres, and the prepared product exhibits excellent biocompatibility and structural regularity. It has good industrial application prospects in the field of biomedical implants such as bone tissue repair and is suitable for large-scale production.

The invention provides an omega-transaminase mutant and application thereof, belongs to the technical field of microbial pharmacy and pharmaceutical chemical engineering, and particularly provides the omega-transaminase mutant, and the amino acid sequence of the omega-transaminase mutant is shown as SEQ ID NO.4 or SEQ ID NO.6; the omega-transaminase mutant provided by the invention not only has high enzyme activity, but also can be used for preparing 2-thiophenemethylamine by using 2-thiophenecarboxaldehyde; the engineering escherichia coli for expressing the omega-transaminase mutant is used for performing whole-cell catalysis to prepare the 2-thiophenemethylamine, so that the conversion rate is high, and the concentration of the coenzyme pyridoxal phosphate used in the reaction is reduced.

The invention provides a one-step enzymatic synthesis technology of (2S, 3R)-p-methylsulfonyl phenyl serine ethyl ester. Specifically, the invention provides a method for preparing (2S, 3R)-p-methylsulfonyl phenyl serine ethyl ester by a one-step method, and the method comprises the step of obtaining (2S, 3R)-p-methylsulfonyl phenyl serine ethyl ester from p-methylsulfonyl benzaldehyde and L-threonine ethyl ester or a salt thereof under the action of transaldolase in the presence of phosphopyridoxal as a coenzyme.

The present invention provides a kind of L-threonine aldolase mutant and its application in catalytic synthesis of p-methylsulfonylphenylserine, the L-threonine aldolase mutant source Pseudomonas of the present invention, can use threonine and p-methylsulfonylbenzaldehyde as substrate, with pyridoxal phosphate and reduced nicotinamide adenine dinucleotide as coenzyme, catalysis obtains the synthesis of florfenicol intermediate p-methylsulfonylphenylserine, compared to wild-type L-threonine aldolase, mutant enzyme has higher activity, can effectively improve conversion efficiency, shorten conversion time. The enzyme and technical method reaction conditions of the present invention are mild, pollution is small, and there is good industrial prospect in the production of florfenicol synthetic intermediate.

The present invention is related to an improved process for production of vitamin B2 using a genetically engineered host cell comprising a heterologous enzyme with pyridoxal phosphatase activity. Using said modified host cell, the yield of riboflavin production could be increased by at least about 5%.

The invention discloses a D-threonine aldolase mutant and application thereof, and relates to the technical field of bioengineering. The amino acid sequence of the D-threonine aldolase mutant is selected from one of SEQ ID NO.8, SEQ ID NO.9, SEQ ID NO.10, SEQ ID NO.11, SEQ ID NO.12 and SEQ ID NO.13; the method for preparing the D-serine comprises the following steps: in the presence of pyridoxal phosphate and magnesium chloride, catalyzing formaldehyde and glycine to react by using the D-threonine aldolase mutant; the invention further discloses the application of the D-threonine aldolase mutant in preparation of D-serine. The highest catalytic activity of the D-threonine aldolase mutant is improved by 2.04 times compared with the enzyme activity of a wild strain, and the productivity of D-serine is remarkably improved.

The invention belongs to the technical field of analytical chemistry, and particularly relates to a preparation method of a directional pore channel integral material and a method for constructing an enrichment device and establishing a rapid phosphopeptide enrichment method by using the directional pore channel integral material. The preparation method comprises the following steps: preparing a CS-PC integral material with directional pore channels from chitosan, zirconium amino phthalocyanine and polyethylene glycol diglycidyl ether through a directional freezing method and a chemical crosslinking method, and then modifying the CS-PC integral material with 5 '-phosphopyridoxal and zirconium oxychloride to obtain the CS-PC PLP integral material. The CS-PC-PLP integral material prepared by the invention has anisotropy and a directional pore channel structure, is convenient to fix in a pipette tip and is combined with a row pipettor for rapid enrichment; the CS-PC coated PLP integral material has the advantages of green and cheap raw materials and strong reusability.

The invention discloses homogeneous mixing equipment for pyridoxal phosphate processing, and relates to the technical field of mixing, and the homogeneous mixing equipment comprises a mixing device. According to the homogenizing and mixing equipment for pyridoxal phosphate processing, through the design of the mixing device, materials enter the mixing shell from a feeding pipe, a first motor controls a center rotating shaft to rotate, the center rotating shaft drives a stirring column to rotate, and the effect of stirring and mixing the materials is achieved, so that the mixing operation requirement is met, and the situation that the materials are wet before stirring exists; a cutter is arranged on the inner side of the stirring column and is used for cutting the caked materials in the rotating process, so that the effect of crushing larger cakes is achieved, the flowing speed of the materials is controlled through a discharging valve, the situation that the mixing effect of the materials is influenced due to the too high flowing speed is avoided, and the mixing time is provided for equipment; the stirring mechanism rotates to increase flowing of materials at the bottom of the equipment, alternate accumulation of material particles is prevented, descending of blocked materials is avoided, and therefore normal operation of the equipment is kept.

The invention provides a pyridoxine phosphate oxidase mutant and application of the pyridoxine phosphate oxidase mutant in synthesis of pyridoxal phosphate. The mutant is obtained by performing one or more mutations on an amino acid sequence as shown in SEQ: ID: NO: 4, wherein the amino acid sequence contains the 24th site (D24N), the 141 site (Q141S), the 190 site (R190G) and the 195 site (H195A) as a mutant 1; the mutant 2 contains a 66th site (R66K), a 141 site (Q141S), a 180 site (Q180T) and a 193 site (R193H); and the mutant 3 contains the 141 site (Q141S) and the 190 site (R190G). Compared with wild type pyridoxine phosphate oxidase, the pyridoxine phosphate oxidase mutant disclosed by the invention has relatively high catalytic efficiency, and when the pyridoxine phosphate oxidase mutant is used for synthesizing pyridoxal phosphate, the conversion rate of 99.76% or above can be realized within 5 hours.

The invention relates to the technical field of polymer synthesis, in particular to polymer microspheres and a preparation method and application thereof.The preparation method of the polymer microspheres comprises the following steps that pyridoxal, an anhydrous aprotic polar solvent, organic alkali and methacryloyl chloride are mixed to be subjected to an esterification reaction under the conditions of protective gas and light shielding, and the polymer microspheres are obtained. Pyridoxal methacrylate is prepared; dissolving inorganic salt and a dispersing agent in water to prepare a water phase; the preparation method comprises the following steps: mixing pyridoxal methacrylate, styrene, divinyl benzene and an initiator to prepare an oil phase; heating the water phase to 65-75 DEG C, and adding the oil phase into the water phase under a stirring condition to prepare a suspension dispersion system; under the protection of protective gas, the suspension dispersion system is subjected to a reaction for 8-12 h at the temperature of 65-75 DEG C, the polymer microspheres are prepared, and the polymer microspheres can keep efficient adsorption of uranyl ions within a wide pH range.

The invention discloses an application of pyridoxal phosphate in preparation of drugs or antibiotic synergists for treating bacterial infectious diseases. According to the invention, the pyridoxal phosphate (the active form of vitamin B6) has a relatively strong drug-resistant pathogenic bacterium resisting effect in vivo and in vitro when being combined with the antibiotic polymyxin for use for the first time, and the curative effect of the polymyxin can be effectively improved; when the pyridoxal phosphate and the polymyxin are used for treating gram-negative bacterium infectious diseases, the survival rate of greater wax moths and mice can be remarkably improved and the inflammation level of the organism can be reduced through combined medication of the pyridoxal phosphate and the polymyxin. The invention provides a new thought for the control of drug-resistant pathogenic bacteria, and also provides a new strategy for the prevention and treatment of increasingly serious gram-negative bacterial infection.

The invention discloses a chain-shaped silver complex as well as a preparation method and application thereof. The invention relates to a synthesis method of a chain-like silver complex, which comprises the following steps: carrying out condensation reaction on pyridoxal and p-methylbenzenesulfonyl hydrazide to generate a pyridoxal condensed p-methylbenzenesulfonyl hydrazide ligand, reacting the ligand with silver nitrate, slowly volatilizing the reaction liquid for 3-5 days, and separating out a yellow crystal of the chain-like silver complex. The crystal is subjected to structural analysis by adopting an X-ray single crystal diffraction technology, and the result shows that the crystal is a novel chain-shaped coordination polymer. The chain-shaped silver complex shows remarkable antibacterial activity on staphylococcus aureus, pseudomonas aeruginosa, methicillin-resistant staphylococcus aureus and multi-drug-resistant pseudomonas aeruginosa, and the in-vitro antibacterial effect of the chain-shaped silver complex is superior to that of silver nitrate, a ligand and a methicillin monomer; the application potential of the compound serving as an efficient antibacterial agent in the aspect of replacing or supplementing existing anti-infection drugs is shown. The structure of a pharmaceutically acceptable compound of the chain-shaped silver complex is shown as a formula (I) in the specification.

The invention provides a pyridoxine 5 '-phosphate oxidase mutant and an application of the pyridoxine 5'-phosphate oxidase mutant in synthesis of pyridoxine 5 '-phosphate. The mutant is obtained by mutating the amino acid sequence of pyridoxine 5 '-phosphate oxidase DrPNPO, and the mutation site comprises at least one of the 45th amino acid, the 68th amino acid, the 91th amino acid, the 114 amino acid, the 127th amino acid, the 141 amino acid, the 147th amino acid, the 158th amino acid, the 174th amino acid and the 205th amino acid. Compared with wild type pyridoxine phosphate oxidase, the pyridoxine 5 '-phosphate oxidase mutant disclosed by the invention has higher catalytic efficiency, the pyridoxine 5'-phosphate oxidase mutant can be used for efficiently synthesizing pyridoxine 5 '-phosphate through a whole-cell catalytic reaction only in 4 hours, and the conversion rate reaches 99% or above.

The invention belongs to the technical field of biology, and particularly relates to a method for efficiently synthesizing vitamin B6 by using bacillus subtilis. The method for synthesizing the vitamin B6 by using the bacillus subtilis comprises the following steps: PDX1, PDX2 and PLPP are simultaneously expressed in the bacillus subtilis, PDX1 and PDX2 are two subunits of phosphopyridoxal synthetase, and the amino acid sequences of PDX1 and PDX2 are shown as SEQ ID NO: 4 and SEQ ID NO: 5; pLPP is phosphopyridoxal phosphatase, and the amino acid sequence of PLPP is shown as SEQ ID NO: 6. The method realizes efficient production of vitamin B6 in bacillus subtilis, and has wide application prospects in the fields of food additives and pharmaceutical industry.

The invention discloses a D-amino acid transaminase mutant and a method for preparing 4-chloro-D-phenylalanine by using the D-amino acid transaminase mutant. The method comprises the following steps: in the presence of a buffer solution, an amine source and pyridoxal phosphate, catalyzing a compound II by using the D-amino acid transaminase mutant to generate a transaminase reaction to generate 4-chloro-D-phenylalanine, the amino acid sequence of the D-amino acid transaminase is as shown in SEQ ID NO: 1; the structural formula of the 4-chloro-D-phenylalanine is shown as a compound I. According to the mutant and the method, efficient and high-stereoselectivity biological catalytic synthesis of the 4-chloro-D-phenylalanine is realized on the basis of specific catalysis of the D-amino acid transaminase mutant obtained by directed evolution on 4-chlorphenyl pyruvic acid.

The invention discloses a method for preparing tyramine, which comprises the following steps that tyrosine is used as a substrate, in the presence of pyridoxal phosphate, tyrosine decarboxylase SEQ ID NO: 1 derived from streptococcus thermophilus or mutants SEQ ID NO: 3-5 of tyrosine decarboxylase SEQ ID NO: 1 are used for catalyzing decarboxylation reaction, tyramine is obtained, and the method has industrial development value.

The invention relates to the technical field of bioengineering, and provides a preparation method for synthesizing aminobutyric acid through whole-cell immobilization efficient catalysis. The method comprises the following steps: firstly, adding urea as a nitrogen source in the culture process of corynebacterium glutamicum, and feeding glycerol, sorbitol and biotin complex liquid to culture thalli; then carrying out low-temperature incubation treatment on the thalli by using pyridoxal phosphate, and then carrying out mixed incubation with mercapto-histidine trimethyl inner salt; then preparing an embedding carrier solution by using sodium alginate, polyvinyl alcohol and graphene oxide, and adding glutaraldehyde as a cross-linking agent; mixing the treated thalli with an embedding carrier, and adding a mixture of boric acid and calcium chloride; and finally, dropwise adding the mixed solution into a sodium sulfate solution to form gel particles, and storing the gel particles by using an acetic acid-vitamin C composite buffer solution. The immobilized cells prepared by the method have high mechanical strength, high cell encapsulation rate and high conversion rate, are suitable for long-term preservation, still have activity of 90% or more of the original activity after being refrigerated for 10 days, and still have yield of 360 g / L or more after being used for 10 batches.

A pyridoxal kinase mutant is provided. To solve the problem of low concentration of existing enzyme catalyzed products, provided is a pyridoxal kinase mutant having an amino acid sequence selected from an amino acid sequence as shown in SEQ ID NO: 1 in which lysine at position 229 is mutated to alanine, phenylalanine, arginine, threonine, histidine, serine, tyrosine, valine, leucine, isoleucine, proline, aspartic acid, or glutamic acid; and the pyridoxal kinase mutant is used to catalyze the synthesis of pyridoxal phosphate from pyridoxal.

The invention relates to the technical field of microorganisms, and discloses an improved LST broth culture medium and application, and the improved LST broth culture medium comprises tryptone, ammonium chloride, lactose, dipotassium phosphate, monopotassium phosphate, sodium lauryl sulfate, Rpf recombinant protein, magnesium sulfate, sodium pyruvate and pyridoxal phosphate. The improved LST broth culture medium disclosed by the invention can be used for successfully enriching the VBNC-state escherichia coli, so that researchers can successfully detect the VBNC-state escherichia coli in a culture manner.