387 results about "Enzyme catalyzed" patented technology

The invention relates to the technical field of biological catalysis, and discloses an L379A mutant enzyme for preparing rebaudioside I. The enzyme is obtained by the following mutations generated by UGT76G1: leucine of the 379th amino acid sequence is mutated into alanine; the enzyme can be applied to RA in-vitro conversion preparation of RI with higher utilization value, the conversion rate is higher than 50%, and the enzyme activity is remarkably improved by 7 times compared with the original enzyme catalytic conversion enzyme activity. The UGT76G1 mutant disclosed by the invention has the advantages that (1) the blank is filled, and a special enzyme catalyst capable of realizing efficient in-vitro synthesis of rebaudioside I (RI) is provided for the first time; 2) efficiency jump: the catalytic conversion rate is greatly increased from original about 7% to more than 50% (increase gt; and 3) stability and reliability: in the cross-scale reaction of 10mL to 5L, the catalyst has stable catalytic performance, shows excellent industrial application potential, and is suitable for popularization and application.

The invention belongs to the field of enzymatic preparation of structural phospholipids, and particularly relates to a method for preparing phosphatidylserine through interfacial enzyme catalysis. A series of high-activity immobilized phospholipase are prepared by innovatively adopting bifunctional group modified hollow mesoporous silica microspheres as a carrier and adsorbing immobilized phospholipase D. The catalyst has the functions of a catalyst and an emulsifier, and a Pickering emulsion interfacial enzyme catalysis system can be efficiently constructed. In the system, the phosphatidylcholine and the serine are efficiently converted into the phosphatidylserine through a phosphatidyl transfer reaction, the conversion rate of the phosphatidylserine within 20 minutes can reach 85%-95%, and the catalytic efficiency reaches up to 372 mmol / (g.h). In addition, after the catalyst is recycled for 10 times, the conversion rate is still kept at 70.9%, and the catalyst shows excellent stability and reusability. The method has the remarkable advantages of being mild in reaction condition, high in catalytic efficiency, capable of being repeatedly used and the like, and a new technical approach is provided for industrial production of phosphatidylserine.

The present invention relates to an enzyme catalyst for preparing a dicarboxylic acid and a method for preparing a dicarboxylic acid using the same. The enzyme catalyst is prepared by a method comprising the following steps: (1) carrying out fermentation culture on enzyme-producing microorganisms in a culture medium to obtain a crude enzyme solution, and (2) immobilizing the crude enzyme solution on a molecular sieve to obtain the enzyme catalyst, wherein the enzyme producing microorganisms are selected from candida tropicalis, candida sake, pichia pastoris, saccharomyces cerevisiae, lactobacillus brevis, corynebacterium glutamicum, bacillus subtilis, bacillus cereus, escherichia coli and pseudomonas aeruginosa. The method comprises the following steps: in a PBS buffer solution, mixing triglyceride with the enzyme catalyst, and carrying out catalytic reaction under stirring at 20-50 DEG C; and then carrying out hydrolysis reaction at the temperature of 250-300 DEG C under the pressure of 30-100 bar. According to the method, the enzyme catalyst and the molecular sieve are immobilized, so that other oxidants or catalysts are not required to be added while the dicarboxylic acid with higher yield is obtained.

Processes for transesterifying wax esters. Implementations may include: providing a feedstock including wax esters, contacting the feedstock with a lipase, and catalytically transesterifying the wax esters in the feedstock with the lipase to form a transesterified product. An oxidative stability index (OSI) of the transesterified product may be greater than an OSI of the feedstock.

The invention provides an application of inositol monophosphate in an enzyme catalysis reaction system for preparing inositol. The invention also provides a preparation method of the inositol, the starch is used as a substrate, glucan phosphorylase, glucose phosphate mutase, inositol-3-phosphate synthase and inositol monophosphate are added as enzyme catalysts to catalyze the substrate to generate the inositol, the inositol monophosphate is derived from Archaeoglobus fulgidus, the amino acid sequence is shown as SEQ ID NO: 12, or the amino acid sequence is shown as SEQ ID NO: 1, or the amino acid sequence is shown as SEQ ID NO: 2, or the amino acid sequence is shown as SEQ ID NO: 3, or the amino acid sequence is shown as SEQ ID NO: 4, or the amino acid sequence is shown as SEQ ID NO: 5, or the amino acid sequence is shown as SEQ ID NO: 6. The inositol monophosphate is derived from Thermococcus kodakarensis, and the amino acid sequence of the inositol monophosphate is as shown in SEQ ID NO: 13; or the inositol monophosphate is derived from Pseudothermotoga lettinae, and the amino acid sequence of the inositol monophosphate is as shown in SEQ ID NO: 14. Inositol-3-phosphate synthetase and inositol monophosphate with good performance are screened, high-concentration starch is efficiently catalyzed to be converted into inositol by a one-pot method in a whole-cell feeding mode, and NAD < + > and other coenzymes do not need to be used. Under a 60L reaction system, 200g / L of corn starch is catalyzed, the unit yield of the prepared inositol reaches 161g / L, and the method has a good industrial application prospect.

Processes for transesterifying wax esters. Implementations may include: providing a feedstock including wax esters, contacting the feedstock with a lipase, and catalytically transesterifying the wax esters in the feedstock with the lipase to form a transesterified product. An oxidative stability index (OSI) of the transesterified product may be greater than an OSI of the feedstock.

The invention relates to the technical field of biocatalytic synthesis of fatty glyceride, in particular to a flaky zeolite immobilized Candida antarctica lipase B catalyst and a method for preparing medium-chain glyceride through catalytic esterification of the flaky zeolite immobilized Candida antarctica lipase B catalyst. The flaky zeolite is flaky silica-alumina zeolite ZSM-5-P, and the loading capacity of the candida antarctica lipase B is 9-12% of the mass of the flaky zeolite. The candida antarctica lipase B is loaded and fixed in the flaky zeolite to prepare the solid catalyst, and the catalyst is a solid enzyme biocatalyst, is small in usage amount, high in catalytic efficiency and recyclable, is used for preparing the medium-chain glyceride, is high in efficiency, low in cost, simple in process, mild in condition, safe and environment-friendly, and has a wide application prospect.

The invention discloses ethanol dehydrogenase, recombinant genetically engineered bacteria and application of the ethanol dehydrogenase in asymmetric reduction of prochiral carbonyl compounds, the ethanol dehydrogenase has good biological performance, heterologous expression in Escherichia coli engineering bacteria is achieved, intracellular coenzyme can be directly utilized when whole cells are adopted as a catalyst, and the catalyst has a good application prospect. Zero addition of the coenzyme is realized, the enzyme has the advantages of high activity, high stereoselectivity, wider substrate spectrum and the like, prochiral ketone compounds can be greenly and efficiently catalyzed to be converted into corresponding chiral alcohols, and the problems of low conversion rate, low yield, low e.e. Value, complex reaction process, more byproducts and the like in a traditional chemical method are solved. The ethanol dehydrogenase has good tolerance to isopropanol, and the isopropanol can be used as a hydrogen source to realize the circulation of coenzyme. And the byproduct acetone generated by the enzyme catalytic reaction and the isopropanol remaining in the reaction can be separated and recovered by a technical means, so that the production cost is greatly reduced.

The invention discloses a 7alpha-hydroxysteroid dehydrogenase mutant with improved catalytic activity as well as a coding gene and application thereof, and the amino acid sequence of the 7alpha-hydroxysteroid dehydrogenase mutant is obtained by mutation at one or more sites of the 120th site, the 195th site and the 207th site on the basis of the amino acid sequence shown in SEQ ID NO: 1. According to the 7alpha-HSDH mutant disclosed by the invention, the key site of the 7alpha-HSDH enzyme is modified, so that the mutant with higher activity than that of a wild enzyme is obtained, the efficiency bottleneck in UDCA biosynthesis is effectively broken through, and an efficient and green enzyme catalyst is provided for industrial application.

The invention discloses application of laccase as a catalyst in catalytic synthesis of allantoin. According to the invention, laccase from thermophilus is used as an enzyme catalyst, uric acid is oxidized, hydrolyzed and decarboxylated to synthesize allantoin, and efficient biosynthesis of allantoin is realized under mild conditions; wherein the amino acid sequence of the laccase derived from the thermophilic fungi is as shown in SEQ ID NO. 1. The invention provides an efficient, environment-friendly and low-cost biosynthesis approach for biosynthesis of allantoin, and has industrial application prospects in biosynthesis of allantoin.

The invention discloses a method for producing p-coumaric acid through double-enzyme cascade catalysis, which comprises the following steps: taking phenol, pyruvic acid and ammonium chloride as substrates, and carrying out cascade enzyme catalytic reaction on a tyrosine phenol lyase product and a tyrosine ammonia lyase product to synthesize p-coumaric acid. According to the method, phenol, pyruvic acid and ammonium chloride are used as substrates, a tyrosine phenol lyase product and a tyrosine ammonia lyase product are used as catalysts, the tyrosine phenol lyase product can convert the substrates into L-tyrosine, and the tyrosine ammonia lyase product can directly use the L-tyrosine as the substrate to convert the L-tyrosine into p-coumaric acid. Therefore, the tyrosine phenol lyase product and the tyrosine ammonia lyase product can realize cascade enzyme catalytic reaction in the same reactor, phenol with lower cost can be adopted as a conversion substrate, separation and purification of an intermediate product L-tyrosine are avoided, and the whole process flow is simple and efficient.

The invention relates to the technical field of NADPH regeneration and the technical field of antidepressant drug synthesis, and discloses a method for catalytically synthesizing (S)-3-chloro-1-phenyl-1-propanol by driving a WO3-based photoenzyme catalyst through infrared light, and the method comprises the following steps: step S1, preparing an oxygen-deficient WO3 nanosheet; s2, preparing a NaCBR carbonyl reductase (NaCBR carbonyl reductase); s3, mixing the oxygen-deficient WO3 nanosheet and NaCBR carbonyl reductase according to the mass ratio of (1: 0.5)-(1: 2), and stirring for 3-6 hours to obtain the photo-enzyme catalyst (WO3 / NaCBR). According to the method, artificial photosynthesis, namely a method for driving NADPH regeneration, is utilized, other materials are not additionally used as hydrogen transfer and electron transfer media, and the (S)-3-chloro-1-phenylpropanol is catalytically synthesized by utilizing infrared light to drive a photo-enzyme catalyst (WO3 / NaCBR). The method can greatly reduce the cost, is green and environment-friendly, has high catalytic efficiency and mild reaction conditions, is simple to operate, is easy to recover and recycle, and is suitable for large-scale industrial production and application.

The invention discloses an application of an isoeugenol monooxygenase mutant in production of isoeugenol vanillin, which comprises the steps of recombinant strain construction, fermentation culture of recombinant strains and catalytic reaction of fermentation broth, and the isoeugenol monooxygenase mutant is mutated through an isoeugenol monooxygenase amino acid sequence of wild fungi WT. And the thalli are expressed by escherichia coli, so that a series of thalli with a promoting effect on the catalytic efficiency of vanillin production are formed. The mutant super-efficient enzyme catalyst with the catalytic conversion rate reaching up to 98.5% or above is obtained through screening, the defects of low efficiency, pollution, high energy consumption and the like of traditional chemical catalyst production are overcome, and the mutant super-efficient enzyme catalyst is more suitable for green industrial production requirements and worthy of being popularized to industrial use.

The invention relates to the technical field of biology, in particular to a purification method of ergothioneine. The invention provides a method for purifying high-purity ergothioneine from an enzyme catalytic reaction. According to the method, high-purity ergothioneine is purified from the enzyme catalysis reaction liquid, so that the purification steps are greatly simplified, and the total purification yield is increased; and only a single organic solvent ethanol is used for crystallization, so that the ergothioneine product with high purity and uniform and thick particles is obtained, and the method is suitable for large-scale production of ergothioneine.

The invention relates to the technical field of enzyme catalysis, relates to the technical field of bioengineering application, and in particular relates to a magnetic nitrilase catalyst for green cyclic synthesis of organic acid as well as a preparation method and application of the magnetic nitrilase catalyst. According to the method, nitrilase escherichia coli is fixed on a magnetic composite carrier in a covalent binding and adsorption-crosslinking manner to form a magnetic nitrilase catalyst, and the catalyst is used for catalytic synthesis of organic acid; after the reaction is finished, the magnetic nitrilase catalyst is recovered by magnetic attraction, and the reaction waste liquid is acidized to realize the purpose of green cyclic synthesis of the organic acid. The prepared magnetic nitrilase catalyst can stably exist in nitrile substances and has the advantages of being high in mechanical strength, low in enzyme activity loss rate and easy to store, the magnetic nitrilase catalyst and reaction liquid can be recycled, beneficial reference is provided for promoting clean, environment-friendly and efficient enzyme method production of organic acid, and the application prospect is wide. The method has huge application potential in continuous separation and industrial application.

The present invention belongs to the technical field of synthesizing and preparing organic polymer optical materials, and specifically relates to a method for preparing a pentaerythritol tetramercaptocarboxylate composition. The method comprises the following two steps: first, an addition reaction of thiourea with acrylic acid under photocatalysis to generate mercaptopropionic acid in situ; and second, a lipase-catalyzed esterification reaction of mercaptopropionic acid with pentaerythritol to obtain colorless, transparent, high-purity pentaerythritol tetramercaptocarboxylate. Simultaneously, a polymerizable modified polyurethane optical material containing the pentaerythritol tetramercaptocarboxylate is prepared, characterized by low cost, high light transmittance, and adjustable refractive index.

The invention provides a glutaminase mutant and application of the glutaminase mutant. Wherein the glutaminase mutant comprises (a) a protein which is subjected to amino acid mutation and has a glutaminase activity function on at least one of the following sites of S467, Y334, K400, N521, R337, E402 or D447 of an amino acid sequence as shown in SEQ ID NO: 2, and (b) a protein which is subjected to amino acid mutation on at least one of the following sites of S334, Y334, K400, N521, R337, E402 or D447 of the amino acid sequence as shown in SEQ ID NO: 2; and (b) a protein which has 80% or more homology with the amino acid sequence limited by (a) and has a glutaminase function. The glutaminase mutant with the amino acid sequence disclosed by the invention has relatively high specific enzyme activity during enzyme catalytic reaction, and is low in cost and strong in market competitiveness when being used for commercial food processing.

The invention relates to a porphyrin iron-based biomimetic enzyme catalytic membrane for water treatment as well as preparation and application thereof, and belongs to the technical field of catalytic membranes. The porphyrin iron-based biomimetic enzyme catalytic membrane comprises a microfiltration membrane basement membrane and a porphyrin iron-based biomimetic enzyme catalyst loaded on the surface of the basement membrane in a chemical crosslinking mode, and the porphyrin iron-based biomimetic enzyme catalyst contains a catalytic activity center structure of 'Fe-N' coordination. The porphyrin iron-based biomimetic enzyme prepared by the invention is similar to a catalytic active center structure of natural peroxidase, has high affinity with hydrogen peroxide, and can greatly improve the utilization rate of hydrogen peroxide and the steady-state concentration of reactive oxygen free radicals; the constructed bionic enzyme-membrane reactor integrates dual functions of membrane separation and enzyme catalysis, realizes efficient combination of mass transfer and reaction, and greatly improves the removal performance of new pollutants in water.

The invention relates to the technical field of catalysis, and particularly discloses a method for preparing pure biodiesel from kitchen waste oil through enzyme catalytic desulfurization. The method comprises the following steps: adding a Sm2O3 / ZrO2 solid acid catalyst into the kitchen waste oil for pretreatment to obtain pretreated waste oil, and then adding lipase into the pretreated waste oil for catalyzing transesterification to obtain the biodiesel. According to the method for preparing the pure biodiesel from the kitchen waste oil through enzyme catalytic desulfurization, in-situ esterification and synchronous desulfurization of free fatty acid can be completed in a single-step reaction, the stability of a conversion reaction is effectively improved, the production process is simplified, and the conversion efficiency of preparing the biodiesel from the kitchen waste oil is improved.

The present application relates to a kind of sulfide monooxygenase mutant and its application in esomeprazole synthesis.The sulfide monooxygenase mutant, its encoding gene, the preparation method of the recombinant expression vector containing the gene sequence, co-expression recombinant vector and recombinant expression transformant, and the application of the recombinant sulfide monooxygenase mutant catalyst in esomeprazole synthesis are specifically disclosed.Compared with other sulfide monooxygenases, the sulfide monooxygenase mutant obtained by the present application can efficiently utilize the coenzyme NADH with lower cost and higher stability to catalyze the asymmetric oxidation reaction of omeprazole sulfide, prepare esomeprazole, has the advantages of high substrate concentration, mild reaction condition, environment-friendly, simple operation, high yield, low production cost and good industrial application prospect.

The invention discloses a feed low-temperature sterilization method based on a composite biological enzyme synergistic effect. The feed low-temperature sterilization method comprises the following steps: a pretreatment stage; a dynamic reaction stage: under the conditions that the temperature is 40-50 DEG C and the humidity is 60%-70%, the enzyme catalytic reaction lasts for 30 minutes, and the microbial structure is decomposed; and inactivating the activity of the residual enzyme through short-time pulsed ultraviolet rays. The compound enzyme comprises lysozyme, thermophilic protease and lipoxygenase, and the nano chitosan carrier and the compound enzyme are mixed according to the mass ratio of 1: 1. According to the method, damage to heat-sensitive nutritional ingredients is avoided through low-temperature operation (40-50 DEG C), broad-spectrum sterilization is achieved through the synergistic effect of compound enzymes, multiple microorganisms such as bacteria, molds and spores are covered, meanwhile, it is guaranteed that no chemical residues exist through the ultraviolet inactivation technology, and animal health and environment safety are guaranteed. The method is low in equipment cost, easy and convenient to operate and free of public acceptance problems, a green, efficient and economical solution is provided for the feed processing industry, and the efficiency and safety of the feed sterilization technology are remarkably improved.

The utility model discloses a fish oil distillation retort capable of increasing EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) contents, and relates to the technical field of fish oil purification. The barrel body is arranged in the tank body; the pump assembly is used for adding a catalyst in the catalyst box into the barrel; and the stirring assembly is used for stirring the fish oil, the buffer solution and the catalyst in the barrel so as to form a mixed solution. After a catalyst in the catalyst box is fed into the barrel body by the pump assembly, fish oil, a buffer solution and enzyme are stirred and mixed by the stirring assembly, so that the reaction is accelerated, the enzyme catalyst is added into the barrel body in batches, the reaction process is adjusted more accurately, waste is avoided, and the cost of the enzyme catalyst is saved; and after stirring and heating reaction for a period of time, centrifuging the obtained mixture, standing for a period of time for liquid separation, and distilling the upper oil phase to obtain the fish oil with higher EPA and DHA contents.

The invention belongs to the technical field of organic synthesis, and particularly relates to a process for catalytically synthesizing ascorbyl tetraisopalmitate by a biological enzyme. The synthesis process comprises the following steps: attaching a biological enzyme to a metal organic framework compound material (MOFs material) to prepare biological enzyme catalyst powder, and adding a small amount of biological enzyme catalyst powder into methyl n-hexylcaprate and ascorbic acid which are used as raw materials for transesterification to prepare ascorbyl tetraisopalmitate. The process route is simple, few three wastes are generated, compared with a traditional preparation process of tetra-isopalm ascorbate, the yield and purity of the product are greatly improved, and experimental results show that the highest yield of the product is 89%, and the purity of the product reaches 99.0%.

The invention discloses an immobilized enzyme catalyst based on a bifunctional covalent organic framework. An EBCOF nanosheet functionalized based on a quaternary ammonium group has dual functions of enzyme loading and silicification induction. The preparation method mainly comprises the following steps: firstly, adsorbing enzyme on the surface of the EBCOF nanosheet through electrostatic interaction, and then inducing a silicon oxide coating to be formed on the surface of the EBCOF nanosheet in situ through a quaternary ammonium group on the EBCOF nanosheet. The ultrathin EBCOF nanosheet has high enzyme loading capacity, and 3.4 milligrams of enzyme can be adsorbed by each milligram of the EBCOF nanosheet. And meanwhile, the formed silicon oxide coating effectively protects enzyme molecules. Compared with direct adsorption of the enzyme on the EBCOF, the existence of the silicon oxide coating improves the temperature, pH and cycling stability of the immobilized enzyme. The method can be expanded to construction of an immobilized multi-enzyme catalytic system. Compared with a free enzyme system, the initial activity of the immobilized multienzyme catalytic system is improved by 143%.

The invention discloses a resourceful treatment process for phenol-ammonia wastewater. The process comprises the following steps: pretreating to remove oil, acid and ammonia, and recovering ammonia water; preparing a silicon-based supported phenol oxidase catalyst; carrying out enzyme catalysis polycondensation on the pretreated wastewater to generate polyphenols; residual phenol is deeply removed through electrochemical feeding of the three-dimensional electrode; after polyphenol substances are separated, supernate is subjected to biochemical treatment and is discharged after reaching the standard; and finally, carrying out dehydration, granulation, segmented pyrolysis graphitization and post-treatment on the collected polyphenol sludge to prepare the carbon negative electrode material. According to the method, deep purification of the phenol-ammonia wastewater and collaborative recycling of pollutants are achieved, toxic phenols are converted into carbon material precursors with high additional value, the recycled ammonia water can be used for desulfurization and denitrification of a boiler, and the method has the advantages of being thorough in treatment, high in resource recovery rate, low in cost and remarkable in environmental benefit.

The invention relates to the technical field of enzyme catalytic reaction equipment, and discloses a transglucosidase catalytic reaction device capable of avoiding infectious microbe infection.The transglucosidase catalytic reaction device comprises a catalytic reaction device body, a motor body is installed on the catalytic reaction device body, and the output end of the motor body is connected with a stirring shaft through a coupler; a motor body is started to drive a stirring shaft, meanwhile, under the cooperation of a transmission assembly, an overturning scraping plate on a cleaning scraping base can do circular motion, residual materials attached to the inner wall of the catalytic reaction device body can be scraped away, and when materials continue to be put into the catalytic reaction device body, the materials can be automatically cleaned by starting a second electric telescopic rod, so that the materials can be automatically cleaned. And meanwhile, under the cooperation of a disinfection cleaning assembly, the overturning scraping plate with impurity cakes is overturned into a cleaning scraping base to be subjected to isolation cleaning, if residual materials on the inner wall are attached for a long time, the residual materials can chemically react with the inner wall of the reaction device, the inner wall is corroded and abraded, and the structural integrity and performance stability of equipment are affected.

The present invention discloses a mutant dual-enzyme catalyst, application and (S)-Bosin synthesis method, relating to the field of bioengineering technology, the present invention is based on the methylglyoxal reductase GRE2 (A) of Candida glabrata and the phosphite dehydrogenase PTDH of methylotrophic bacteria as sources for transformation, and its mutants are screened, the key residues affecting the enzymatic properties of the initial methylglyoxal reductase and phosphite dehydrogenase are determined, and methylglyoxal reductase mutants and phosphite dehydrogenase mutants with high activity are obtained. The present invention utilizes the two most efficient mutants to catalyze the reaction of preparing (S)-Bosin from β-acetone xyloside in a 22T reaction system, with good catalytic effect, overall catalytic efficiency is increased by about 43%, and cost is reduced by about 8%.

The invention discloses an immobilized enzyme catalyst based on an epoxy modified covalent organic framework (COF) carrier and a preparation method of the immobilized enzyme catalyst, and belongs to the technical field of biological catalysis. The preparation method comprises the following steps: firstly, mixing COF-OH, epoxy chloropropane and a sodium hydroxide solution, stirring and reacting for 6-24 hours to obtain a modified material COF-EP; and dispersing COF-EP in a buffer solution, adding an enzyme solution, carrying out a constant-temperature reaction, collecting a solid product, and drying the solid product to prepare the enzyme # imgabs0 # COF-EP catalyst. By adjusting functional groups of COF, the method provides covalent binding sites for enzyme, and compared with physical adsorption, enzyme conformation change is more effectively induced, active sites are more effectively exposed, and therefore the catalytic performance is improved. The obtained catalyst has high enzyme activity, large enzyme loading capacity and excellent operation stability. The preparation method is low in cost, mild in condition and simple and convenient to operate, can be popularized to other immobilized enzyme systems, and expands the application prospect of the COF material in the field of biological catalysis.

The invention belongs to the field of biochemical engineering, and particularly relates to a method for preparing xylitol through continuous catalysis of immobilized enzyme coupled ion exchange, which specifically comprises the following steps: co-immobilizing xylose reductase, glucose dehydrogenase and NADP + coenzyme, producing xylitol through enzyme catalysis by taking xylose and glucose as raw materials, and coupling an ion exchange reaction after the enzyme catalysis reaction to obtain the xylitol. Due to the arrangement of the ion exchange reaction, the byproduct gluconate can be separated, and the pH of the reaction liquid can be regulated and controlled by using alkaline anions exchanged in the ion exchange process, so that the normal operation of the reaction is further ensured; the xylitol and the by-product gluconate obtained by the reaction can be separated without an additional separation process. The method provided by the invention successfully solves the problems of complex process, high separation difficulty and high cost in the process of refining xylitol by a biological method.

The utility model provides a continuous flow micro-reactor for a heparinase catalytic reaction, belongs to the technical field of micro-reactors, and aims to solve the problems that the replacement of immobilized heparinase needs a long time and the efficiency of the heparinase catalytic reaction is influenced. Comprising a limiting supporting base, a positioning mounting frame, a reactor main body, a positioning connecting rod, a first storage tank and a second storage tank, the positioning mounting frame is in bolted connection with the right side of the limiting supporting base; the reactor main body is fixedly connected to the left side of the positioning mounting frame; the positioning connecting rod is rotationally connected to the left side of the reactor main body, and a damper is arranged at the joint of the positioning connecting rod and the reactor main body; the first storage tank is fixedly connected to the middle part of the positioning connecting rod; the second storage tank is in bolted connection with the front side of the first storage tank; according to the utility model, the replacement efficiency of the immobilized heparinase is improved, a large amount of time is saved, and the catalytic reaction efficiency of the heparinase is improved.