1091 results about "Biocatalysis" patented technology

The invention relates to the technical field of biocatalysts, in particular to a FeCo-NC bimetallic monatomic nano-enzyme as well as a preparation method and application thereof. The preparation method of the nano enzyme comprises the following steps: preparing Co-ZIF-8 from zinc nitrate, cobalt nitrate and 2-methylimidazole; the Co-ZIF-8 and ferric chloride are used for preparing the FeCo-NC bimetallic monatomic nano-enzyme, the molar ratio of the zinc nitrate to the cobalt nitrate is (20-30): 1, and the molar ratio of the cobalt nitrate to the ferric chloride is (2-6): 1. The nano-enzyme prepared by the embodiment of the invention is of a monatomic structure, has double-enzyme activity, can simultaneously simulate catalase and NADH oxidase, and has the capability of removing active oxygen.

The invention discloses a fusion enzyme capable of efficiently degrading PET (polyethylene terephthalate) plastic and application of the fusion enzyme. The invention provides a recombinant fusion enzyme. The recombinant fusion enzyme comprises a mutant KL-MHETase of thermophilic carboxylesterase Est30 and a PET (Polyethylene Terephthalate) degrading enzyme FAST-PETase, the amino acid sequence of the mutant KL-MHETase of the thermophilic carboxylesterase Est30 is as shown in SEQ ID NO. 3; the amino acid sequence of the FAST-PETase is as shown in the 284th to 546th amino acids of SEQ ID NO.1 (Sequence Identifier Number 1). The fusion enzyme is used as a biocatalyst, the activity of catalyzing hydrolysis of MHET at 50 DEG C is 52.6 times that of FAST-PETase, and the fusion enzyme has high enzyme activity and thermal stability. PET degradation is catalyzed at the temperature of 50 DEG C, the conversion rate of PET is 90% after 48 hours of reaction, and meanwhile, the TPA content in the product is close to 100%.

The invention discloses a glycosyl transferase UGT76G1 mutant and a method for catalytically synthesizing rebaudioside M by using the glycosyl transferase UGT76G1 mutant, and relates to the technical field of biological catalytic synthesis. The glycosyl transferase UGT76G1 mutant is any one of the following components (A)-(C): (A) a protein obtained by performing any one or more of the following mutations on the basis of an amino acid sequence as shown in SEQ ID NO.1: the 89th amino acid is mutated into H from M; the 380th amino acid is mutated from L to M; the 411th amino acid is mutated from A to Y; (B) a protein which has 95% or 98% or more of identity with the amino acid sequence defined by (A) and has the same function as the amino acid sequence defined by (A); and (C) a fusion protein obtained by connecting a tag to the terminal of the protein defined in (A) or (B). The glycosyl transferase UGT76G1 mutant disclosed by the invention is obtained by mutating and screening glycosyl transferase UGT76G1, has higher catalytic activity, and can be used for efficiently synthesizing rebaudioside M by taking rebaudioside D and UDPG as substrates.

The invention discloses a perchlorate wastewater treatment method which comprises the following steps: discharging perchlorate wastewater into an adjusting tank, and adjusting and buffering water quality in the adjusting tank; discharging the adjusted wastewater into a coagulating basin, and adding a coagulant to react with suspended solids in the wastewater; feeding the wastewater subjected to the coagulation reaction into a sedimentation tank, and completing solid-liquid separation in the sedimentation tank; discharging the precipitate, and enabling the treated wastewater to enter a microbial catalysis tank; perchlorate in the treated wastewater is subjected to biodegradation in a microbial catalysis tank; carrying out MBR (Membrane Biological Reactor) treatment on the wastewater subjected to biodegradation, intercepting microorganisms in the wastewater in a biological catalysis tank, and discharging the wastewater which does not contain the microorganisms and is subjected to biodegradation into an RO (Reverse Osmosis) membrane treatment device; the wastewater is subjected to reverse osmosis treatment at the RO membrane treatment device, reverse osmosis concentrated water is conveyed to the biological catalysis tank, and reverse osmosis fresh water is conveyed back to the water purification tank. The biological enzyme catalysis and membrane separation method is adopted, so that the perchlorate wastewater can be discharged after reaching the standard, and the treatment process is efficient, convenient and low in cost.

The invention discloses a method for efficiently synthesizing epiinositol by using a heat-resistant myo-inositol dehydrogenase mutant cascade system, and belongs to the field of biocatalysis engineering. Whole cells for expressing a scyllo-inositol dehydrogenase mutant and a heat-resistant scyllo-inositol dehydrogenase mutant are utilized to catalyze the scyllo-inositol to synthesize the epiinositol in a two-step cascade manner, and different from reported scyllo-inositol and D-chiral inositol synthesis methods, in the process of synthesizing the epiinositol by taking the scyllo-inositol as a substrate, the C4 position of the scyllo-inositol is dehydrogenated firstly, then the C4 position of the scyllo-inositol is dehydrogenated, and the C4 position of the D-chiral inositol According to the present invention, the structure of the substrate and the structure of the product are symmetric, and the enzyme is difficult to specifically recognize during the catalysis process, such that the synthesis of the different chiral compounds of the inositol is the important problem in the biological catalysis field. The invention provides a brand-new way for biocatalytically synthesizing the epiinositol, the yield of the epiinositol is increased to 1.89 g / L through enzyme modification, the conversion rate is 52.6%, and the yield and the conversion rate are the highest level reported publicly at present.

The invention belongs to the field of bioengineering, and particularly discloses a tryptophan synthetase mutant with improved enzymatic activity and application of the tryptophan synthetase mutant in production of L-cysteine. Compared with wild tryptophan synthetase from escherichia coli, the amino acid sequence of the tryptophan synthetase mutant has the advantages that a beta catalytic subunit has T69A, S143A, R219E and F280H site combined mutation. Researches show that the enzyme activity of the mutant is increased by 2.4 times compared with that of a wild type through enzyme activity determination and analysis of inducible expression and purification. The beneficial tryptophan synthetase mutant provided by the invention can efficiently biocatalyze L-serine and sodium hydrosulfide to synthesize L-cysteine, and has a better industrial application prospect.

The invention discloses a thermostable conjugated polyketoreductase mutant, which is obtained by performing single-point mutation or multi-point combined mutation on the 25th site, the 92th site, the 214th site or the 256th site of an amino acid sequence as shown in SEQ ID NO.1. The invention further discloses a preparation method of the thermostable conjugated polyketoreductase mutant. The initial enzyme activity of the mutant is high, and the residual enzyme activity is gt after incubation at 50 DEG C; the Tm value can be increased by more than 9 DEG C compared with that of an original strain, the 50 DEG C half-life period t1 / 2 is increased by more than 377.8 times, and the thermal stability is obviously improved. The invention also provides a coding gene, a recombinant vector containing the coding gene and a co-expression engineering bacterium. The thermostable conjugated polyketoreductase mutant, glucose dehydrogenase and L-pantolactone dehydrogenase are used for constructing a three-enzyme co-expression engineering bacterium as a biocatalyst, racemization pantolactone is catalyzed to synthesize DPL, for a 1M substrate, the yield of the DPL reaches 97.5% within 36 hours, KPL hydrolysis is avoided, the reaction time is shorter, the product concentration is higher, and the thermostable conjugated polyketoreductase mutant has great market application value.

The present invention relates to mutant enzymes with enhanced properties and processes for oxidation of organic compound substrates using such enzymes. More specifically, provided herein are mutations in cytochrome P450 enzymes that enhance their peroxygenase activity and / or alter product selectivity compared to wild-type cytochrome P450 enzymes. Uses for such mutant cytochrome P450 enzymes are also provided, such as for biocatalytic oxidation of carbon-hydrogen bonds via a peroxygenase pathway, or for oxidizing a substrate which is an organic compound.

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 discloses high-stability immobilized candida antarctica lipase B as well as a preparation method and application thereof, and belongs to the technical field of enzyme engineering and biological catalysis. The preparation method comprises the following steps: modifying resin by adopting a silane coupling agent to obtain silanized resin; carrying out aldehyde functional modification on the silanized resin by using dialdehyde cellulose to obtain alkyl-aldehyde modified resin; candida antarctica lipase B is immobilized by using alkyl-aldehyde modified resin, and after the Candida antarctica lipase B is subjected to interfacial activation on the surface of the alkyl-aldehyde modified resin, the Candida antarctica lipase B is covalently bound with aldehyde on the surface of the alkyl-aldehyde modified resin; the prepared immobilized Candida antarctica lipase B has relatively high activity and stability. The method is simple to operate, the prepared immobilized lipase is high in stability, and the method can be used for preparing the high-stability immobilized lipase on a large scale and has the potential of industrial popularization and application.

The invention discloses a carbonyl reductase mutant as well as a preparation method and application thereof, and belongs to the technical field of enzyme engineering. According to the invention, on the basis of carbonyl reductase BcKRED from Bacillus cereus, a series of dominant mutants are obtained through a method of directed evolution in the field of enzyme engineering. The carbonyl reductase dominant mutant obtained by the invention has high catalytic activity, thermal stability and chiral selectivity reversed with wild-type carbonyl reductase. A green and efficient way is provided for industrial production of chiral alcohol by taking carbonyl reductase as a biocatalyst, and the method has a wide application prospect.

The invention belongs to the technical field of biological catalysis, and particularly relates to four R-transaminase and application thereof in asymmetric synthesis of chiral N-heterocyclic amine active drug intermediates. The amino acid sequences of the R-transaminase disclosed by the invention are shown as SEQ ID NO. 1, SEQ ID NO. 3, SEQ ID NO. 5 and SEQ ID NO. 7. Four kinds of R-transaminase are obtained through gene mining and screening, and recombinant escherichia coli is constructed and expressed by adopting a gene engineering technology. The obtained R-transaminase can be used for synthesizing chiral drug intermediates (R)-3-amino-N-Boc-pyrrole (1b) and (R)-3-amino-N-Boc-piperidine (2b) with high stereoselectivity, and has a good application prospect.

The invention belongs to the field of biological catalysis, and discloses a high-activity PET hydrolase mutant and application thereof. The mutant of the thermophilic PET hydrolase provided by the invention is as shown in 1), 2) or 3): 1) a protein corresponding to an amino acid sequence SEQ ID NO.4; 2) a protein corresponding to the amino acid sequence of SEQ ID NO.6; and 3) a protein corresponding to the amino acid sequence of SEQ ID NO.8. Experiments prove that the modified mutant shows higher catalytic efficiency on PET hydrolysis and can keep activity for a long time at the optimal temperature for PET depolymerization. The activity of the mutant protein BhrM3 for catalyzing PET hydrolysis is improved by 1.82 times compared with that of a wild type and is 1.22 times that of efficient PET hydrolase LCC-ICCG, and the protein melting temperature reaches 92.9 DEG C.

Glycosyltransferase UGT76G1 and UGT91C1 mutants and a method for catalytic synthesis of rebaudioside A, D, and M by using same, pertaining to the technical field of biocatalytic synthesis. The glycosyltransferase UGT76G1 mutant can effectively synthesize rebaudioside A using stevioside STV as a substrate. The glycosyltransferase UGT91C1 mutant is obtained by mutation screening of wild-type glycosyltransferase UGT91C1, has higher enzyme activity and catalytic rate, and can effectively synthesize rebaudioside D using rebaudioside A as a substrate. The glycosyltransferase UGT76G1 mutant can also be obtained by mutation and subsequent screening of glycosyltransferase UGT76G1, has higher catalytic activity, and can effectively synthesize rebaudioside M using rebaudioside D and UDPG as substrates.

The invention discloses a biological catalytic synthesis method of norambrox ether, which comprises the following steps: step 1, starting from trans-nerolidol, carrying out carroll rearrangement reaction to synthesize farnesyl acetone; 2, in the presence of a cofactor, converting farnesyl acetone into high farnesol acetate under catalysis of Bayer-Villiger monooxygenase; step 3, catalyzing the deacetylation of the high-farnesol acetate by using esterase to obtain EE-high-farnesol; and step 4, carrying out enzymatic conversion on farnesol by using the squalene hopaene cyclase mutant to obtain norambrox ether. The transformation process is safe and non-toxic, Bayer-Villiger monooxygenase which is new with a key enzyme, natural co-expressed esterase, alcohol dehydrogenase and squalene and hopaene cyclase mutants matched with the system are used for synergistic transformation, so that not only is the coenzyme for oxidation reaction promoted to be recycled, but also the conversion efficiency is improved; conversion from farnesyl acetone to norambrox ether can be efficiently and specifically catalyzed, and a final product can be directly obtained from a reaction system without separation and purification of an intermediate.

The invention belongs to the field of biological catalytic materials, particularly relates to a sound-sensitive agent based on a metal-pyridine coordination structure as well as a preparation method and application of the sound-sensitive agent, and more particularly relates to a sound-sensitive agent doped with second metal and based on the metal-pyridine coordination structure. Compared with other most reported sound-sensitive agents based on micromolecules, the sound-sensitive agent based on the metal-pyridine coordination structure and the doped second metal and based on the metal-pyridine coordination structure, especially the latter, has higher ultrasonic mediated < 1 > O2 generation activity; in addition, the effects of relieving oxygen deficit, promoting polarization of macrophages to M1 and enhancing immunotherapy are achieved, and therefore the tumor microenvironment of immunosuppression is reversed. When the sonosensitizer provided by the invention is used in combination with a PD-L1 antibody, satisfactory sonodynamic triggered synchronous immune activation is realized, and original and distant metastatic tumors are eradicated impressively.

The invention relates to the technical field of biocatalytic synthesis. The invention particularly relates to a glycosyl transferase mutant and a method for catalytically synthesizing rebaudioside M2 by using the glycosyl transferase mutant. The invention relates to a glycosyl transferase mutant, which is characterized in that the glycosyl transferase mutant is A1) or A2): A1) is a protein which is obtained by substitution of amino acid residues on an amino acid sequence as shown in SEQ ID NO.20, has more than 90% of identity with an original protein and has the same function with the original protein; a2) a fusion protein obtained by connecting a tag to the N end and / or C end of A1).

The invention discloses a recycling method of a waste lithium-ion power battery negative electrode material, which comprises the following steps: deconstructing the waste battery negative electrode material through selective plasma electrolysis, separating organic matters and electrolyte to obtain untreated negative electrode powder, and drying the untreated negative electrode powder to obtain the waste lithium-ion power battery negative electrode material. The powder is refined into uniform particles by adopting a supercritical fluid cooling and crushing technology, the physical structure of the powder is kept, metal elements such as lithium, nickel and cobalt are extracted by utilizing a multi-frequency resonance auxiliary ion exchange technology, impurities are removed, further purification is performed by adopting a superconducting magnetic separation technology and a nanoscale aerosol separation technology, and a high-purity metal solution is generated; metal compounds are generated through an intelligent self-adaptive phase change precipitation technology and are reduced into recyclable metal materials through biological catalytic deposition, the whole recovery process is monitored and optimized through a closed-loop circulation intelligent feedback system, the metal recovery rate is maximized, and harmless treatment is ensured.

The invention relates to the technical field of biological catalysis, and discloses an M88V mutant enzyme for preparing rebaudioside I. The M88V mutant enzyme is obtained by the following mutations generated by UGT76G1: M88V: methionine of the 88th amino acid sequence of UGT76G1 is mutated into valine. Aiming at the technical bottlenecks of low RI yield and poor selectivity in the existing RA biotransformation process, an efficient solution is provided for the UGT76G1 mutant developed by the invention. The mutant can specifically catalyze conversion from RA to RI, and the conversion rate of a target product is remarkably increased to 65% or above from general less than 7%. The excellent catalytic performance of the catalyst is verified in milliliter-level to upgraded reaction systems, the key problems of conversion efficiency and process amplification are solved, and a foundation is laid for large-scale green manufacturing of a high-added-value product RI.

The invention discloses a ferredoxin mutant and application of the ferredoxin mutant in synthesis of murine deoxycholic acid, and belongs to the technical field of biological catalytic enzymes. According to the invention, Escherichia coli is used as a chassis strain to express P450 enzyme OleP, a three-component redox partner library is established, and a redox partner PetH / PetF which is most adaptive to OleP is screened. A high-throughput method based on a characteristic light absorption value is developed, and the lithocholic acid and the murine deoxycholic acid can be rapidly and efficiently detected. And the ferredoxin mutant PetFF64D is screened through semi-rational design of the ferredoxin, so that the conversion rate of catalytically preparing the murine deoxycholic acid can be greatly improved. The method provides a new strategy for improving the biosynthesis of hydroxylated steroids.

The invention discloses a p-nitrophenyl ethyl esterase mutant with high enantioselectivity as well as a construction method and application of the p-nitrophenyl ethyl esterase mutant. The p-nitrophenyl ethyl esterase mutant is obtained by mutating an amino acid sequence of wild p-nitrophenyl ethyl esterase pnbA as shown in SEQ ID NO.1 according to one or a combination of more of the following modes: leucine at the 273rd site is mutated into aspartic acid, phenylalanine at the 314th site is mutated into histidine, and leucine at the 362nd site is mutated into arginine. The mutant pnbA-L273D / F314H / L362R provided by the invention shows optimal catalytic performance (E = 47.16) for racemization-acetic acid pinyl hydrate, the enantiomeric excess value of the mutant is 95.13%, the conversion rate of 1S, 5R-acetic acid pinyl hydrate is 90.42%, the enantioselectivity of the mutant is obviously higher than that of a wild type, and the mutant has great application potential in biological catalytic synthesis of monocyclic monoterpenoid chiral alcohols.

The preparation method comprises the following preparation steps: firstly, crushing dried plumeria rubra petals, soaking the crushed plumeria rubra petals in distilled water, decocting the crushed plumeria rubra petals twice, combining filtrate, and concentrating the filtrate to obtain a plumeria rubra extracting solution; the plumeria rubra extracting solution and a rhodococcus strain are subjected to two-stage seed solution culture, then are mixed with a fermentation culture medium in a specific proportion, and are fermented under proper conditions to generate plumeria rubra fermentation liquor containing 3-cyanopyridine hydratase. Then, the fermentation liquor is subjected to biological catalysis to convert nicotinonitrile into nicotinamide, and through the steps of decoloration, filtration, concentration and the like, the plumeria rubra extract containing nicotinamide is finally obtained.

The invention discloses a 3-ketosteroid-delta1-dehydrogenase mutant and application thereof in synthesis of prednisone acetate, the mutant with high catalytic activity on cortisone acetate is obtained through screening, and a methanol-water phase (Tris-HCl buffer solution) system is adopted to increase the solubility of a substrate so as to improve the biological catalytic efficiency. In a single water phase system (Tris-HCl buffer solution) without methanol, the conversion efficiency is only 64.8% for 60g / L of cortisone acetate, and under the condition that other conditions are the same, the conversion rate in the Tris-HCl buffer solution system with methanol is increased to 92.1%, and the conversion rate is increased by 1.42 times.

The invention discloses a preparation method for synthesizing coal-based carbon quantum dots through microbial catalysis, which comprises the following specific preparation steps: (1) pretreating coal, specifically comprising crushing and sterilizing treatment; (2) combining the pretreated coal sample with selected microorganisms or biological factors, and carrying out fermentation treatment on the coal; (3) after fermentation is completed, dialyzing the coal fermentation liquid to prepare a carbon quantum dot solution; (4) separating and purifying the dialyzed carbon quantum dot solution to remove impurities; and (5) carrying out quick freeze-drying on the separated and purified carbon quantum dot solution to obtain the carbon quantum dots with fluorescent properties. According to the method, microorganisms serve as a core, an aerobic or anaerobic fermentation process is combined, coal resources are fully utilized, and efficient preparation of the coal-based carbon quantum dots is achieved. The method not only has good environmental protection property, but also can provide a new technology for industrial production of the carbon quantum dots, and has important significance for efficient conversion and green chemical synthesis of coal.

The invention discloses a metal supported activated carbon catalyst for efficiently preparing aquacide dichloride and application of the metal supported activated carbon catalyst. The catalyst is prepared by taking activated carbon as a carrier, loading Lewis acid active components such as aluminum ions, zinc ions, iron ions, copper ions and the like through an impregnation method, and carrying out vacuum pyrolysis activation treatment at 300-600 DEG C. The catalyst synergistically catalyzes a nucleophilic substitution reaction of a pyridine derivative and alkyl halide in an aprotic polar solvent such as acetonitrile or nitrobenzene, and synthesis of diquat dichloride can be realized under the conditions that the temperature is 100-180 DEG C and the pressure is 1-3 MPa. In a reaction system, the mass ratio of the pyridine derivative to the catalyst to the solvent is 1: (0.01-0.05): (5-8), and real-time monitoring and regulation are performed through an online infrared spectrum, a liquid chromatograph and a gas chromatograph-mass spectrometer. The purity of the product is more than 99% after the product is subjected to filtration, recrystallization with an ethanol-water mixed solvent and vacuum drying. The catalyst provided by the invention has the characteristics of high activity, strong stability and recoverability, obviously improves the atom economy of the reaction, simplifies the production process, reduces the energy consumption and pollution, and is suitable for large-scale industrial production.

The present application relates to the technical field of biocatalysis and biosynthesis, and specifically discloses a natural blue pigment and a biosynthesis method therefor. The present application uses metabolically engineered bacteria to express indigoidine synthetase and phosphopantetheinyl transferase, to catalyze glutamine and N-acetylglutamine to biosynthesize a natural blue pigment N-acetylindigoidine, and deduces its molecular structure by means of mass spectrometry, nuclear magnetic resonance and other methods. The present application achieves catalytic synthesis of N-acetylindigoidine from glutamine and N-acetylglutamine in Escherichia coli, Corynebacterium glutamicum, Saccharomyces cerevisiae and Streptomyces. Compared with indigoidine, N-acetylindigoidine has a maximum absorption wavelength of 584 nm, possesses better color brightness, and has more stable coloration that is not easily faded, with a very broad application range and industrial production application prospects.

The invention relates to the technical field of biological catalysis, and discloses an M88A mutant enzyme for preparing rebaudioside I. The enzyme is obtained by the following mutations generated by UGT76G1: M88A: methionine of the 88th amino acid sequence of UGT76G1 is mutated into alanine; the key conversion rate of RI is greatly increased from 7% to 85% (increased by more than 12 times), and the utilization rate and economical efficiency of raw materials are remarkably improved; the method can be perfectly reproduced under any test scale (10mL, 100mL and 5L), the conversion rate is always anchored to be more than 85%, and incomparable stability and amplification potential are shown.

The present application relates to the technical field of biocatalysis and biosynthesis, and specifically discloses a blue pigment and a biosynthesis method thereof. In the present application, an indigoidine synthetase and a 4′-phosphopantetheinyl transferase are expressed by a metabolically engineered strain to catalyze the biosynthesis of the blue pigment N-acetyl-indigoidine from glutamine and N-acetylglutamine, and a molecular structure of the blue pigment is inferred by mass spectrometry, nuclear magnetic resonance spectroscopy, etc. The present application achieves the catalytic synthesis of N-acetyl-indigoidine from glutamine and N-acetylglutamine in Escherichia coli (E. coli), Corynebacterium glutamicum (C. glutamicum), Saccharomyces cerevisiae (S. cerevisiae), and Streptomyces. Compared with indigoidine, N-acetyl-indigoidine has a maximum absorption wavelength of 584 nm, and a stable color having high brightness that is not easy to fade. Thus, the blue pigment shows an extensive application range and a promising industrial production prospect.

The invention discloses a method for preparing immobilized lipase Janus particles by an emulsion template one-step method based on a zymoprotein directional adsorption strategy and application of the immobilized lipase Janus particles in a Pickering emulsion catalytic system. The natural hydrophilicity of lipase protein is utilized to drive the lipase protein to form directional adsorption on the surfaces of hydrophobic particles, and the Janus particles with hydrophilic and hydrophobic characteristics are constructed. Firstly, an organic phase containing hydrophobic particles and a water phase containing lipase are oscillated to form an emulsion, so that the lipase in the water phase is accurately adsorbed on the single side of the surface of the particles, and directional connection of zymoprotein and a hydrophobic matrix is realized. Afterwards, the Janus particles are used for constructing a Pickering emulsion system, and a microreactor is built, so that the catalytic efficiency of lipase in hydrolysis, ester synthesis and transesterification reaction is improved. The method is easy to operate, efficient and stable enzyme immobilization can be achieved, the obtained immobilized lipase Janus particles are remarkably superior to free enzyme in biological catalytic activity and cyclic utilization performance, and the application value of lipase in industrial large-scale production is remarkably improved.

The invention discloses a heat-resistant glucose dehydrogenase mutant and a preparation method thereof, and the heat-resistant glucose dehydrogenase mutant specifically comprises five glucose dehydrogenase mutants, namely E96I, I183V, D255M, E96I / I183V and E96I / D255M. Results of enzyme activity determination show that the glucose dehydrogenase mutant provided by the invention has good heat resistance, and after high-temperature treatment, the glucose dehydrogenase mutant still has higher enzyme activity compared with an original enzyme; the glucose dehydrogenase mutant provided by the invention is suitable for establishing NADH and NADPH regeneration systems under a high-temperature condition, and provides an efficient and low-cost new choice for industrial biological catalysis and pharmaceutical application.