335 results about "Psicose" patented technology

The invention discloses recombinant escherichia coli for producing D-psicose and a preparation method of the recombinant escherichia coli, and belongs to the field of genetic engineering. The technical problem to be solved in the invention is how to supply microorganisms for growth by using glycerol, acetic acid, fatty acid and the like as raw materials and prepare D-psicose by using glucose as a raw material. The invention provides recombinant Escherichia coli, which uses glycerol, acetic acid, fatty acid and the like as carbon sources to amplify (grow) the recombinant Escherichia coli, and uses D-glucose as a substrate to prepare D-psicose. According to the recombinant escherichia coli provided by the invention, glycerol, acetic acid, fatty acid and the like can be used as carbon sources for microbial growth, and D-psicose is synthesized by taking D-glucose as a raw material after the microbial growth reaches a certain biomass. Furthermore, a corresponding technical route for synthesizing the D-psicose is established.

The present application discloses a recombinant bacterium for producing D-psicose by fermentation and a preparation method thereof, and belongs to the field of food chemical industry. The technical problem to be solved by the present application is: how to obtain a recombinant bacterium that uses methanol as a raw material for bacterial growth and glucose as a raw material to synthesize D-psicose. By subjecting the recipient bacteria to a purposeful transformation, the microbial strain is provided with the ability to accumulate microbial biomass using methanol and synthesize D-psicose using D-glucose, while preventing the use of D-glucose for microbial growth so that D-glucose is completely converted into D-psicose, thereby improving substrate utilization efficiency. The recombinant polymorphic Hansen yeast provided in the present application can realize the use of methanol and other compounds as raw materials for microbial growth, and after the microbial growth reaches a certain biomass, D-psicose is synthesized using D-glucose as a raw material. And then establish a corresponding technical route for synthesizing D-psicose.

The invention discloses a water-based soldering flux for a photovoltaic N-type battery 0BB assembly and a preparation method of the water-based soldering flux, and belongs to the technical field of soldering flux. The soldering flux is prepared from the following raw materials in parts by weight: 30-60 parts of deionized water, 30-50 parts of an alcohol solvent, 2-8 parts of a high-boiling-point solvent, 1-4 parts of organic acid, 0.1-1 part of a surfactant, 0.1-1 part of an antioxidant, 0.1-1 part of a corrosion inhibitor, 0-1 part of psicose and 0-1 part of trimethylolpropane tricaprylate. According to the invention, the problem of negative influence on tension of thermosetting adhesive and alloying of a fine grid when a traditional soldering flux is applied to a photovoltaic N-type battery 0BB assembly is solved.

The invention discloses a D-psicose 6-phosphate phosphatase mutant and application of the D-psicose 6-phosphate phosphatase mutant in preparation of psicose, and belongs to the technical field of enzyme engineering. According to the invention, site-directed mutagenesis is carried out on an amino acid sequence of D-psicose 6-phosphate phosphatase A6PP, and a combined mutant I21V / Y73F / R115M / T180V / L203I / Q193E is constructed, so that the substrate specificity, the thermal stability and the catalytic activity of the combined mutant are all remarkably improved. The invention further provides application of the combined mutant in preparation of psicose through multi-enzyme cascade catalysis, 150 g / L of maltodextrin can be converted into 97.7 g / L of D-psicose, the conversion rate reaches 65.1%, and the application prospect of the combined mutant in the field of food is widened.

The invention discloses L-rhamnose isomerase and application thereof, and belongs to the technical field of genetic engineering. The amino acid sequence of the L-rhamnose isomerase is obtained by performing the following mutation on an amino acid sequence as shown in SEQ ID NO.1: the 258th amino acid is mutated from D to Q. Compared with the prior art, the L-rhamnose isomerase mutant D258Q is obtained by mutating wild type L-rhamnose isomerase, and compared with the wild type L-rhamnose isomerase, the L-rhamnose isomerase mutant D258Q is higher in enzyme activity and longer in half-life period, so that when the L-rhamnose isomerase mutant D258Q is used for catalyzing the conversion of D-psicose into D-allose, the L-rhamnose isomerase mutant D258Q has the advantages that the enzyme activity is higher, and the half-life period is longer; the catalytic capability is stronger and more durable, and the conversion efficiency of the reaction and the yield of D-allose are improved.

The invention provides a method for converting D-fructose in jujubes into D-psicose by immobilized enzyme, jujube juice containing D-psicose and application, and particularly belongs to the technical field of beverage preparation. The method for converting the D-fructose in the jujubes into the D-psicose by the immobilized enzyme comprises the following steps: mixing the immobilized D-psicose-3-epimerase with jujube juice, carrying out sugar conversion, centrifuging and discarding precipitate to obtain jujube juice containing the D-psicose; the nucleotide sequence of the gene for coding the D-psicose-3-epimerase is as shown in SEQ ID NO. 1 (sequence identifier number 1). According to the method disclosed by the invention, the D-fructose in the jujubes can be effectively converted into the D-psicose.

The invention provides a method for synthesizing D-psicose through fermentation of escherichia coli by using D-glucose and D-xylose. The method comprises the following steps: by taking escherichia coli as a host cell, over-expressing a galactose permease gene galP, a glucokinase gene glk, a 6-phosphate glucose isomerase gene pgi, a D-psicose-6-phosphate epimerase gene alsE with an SUMO tag and a D-psicose-6-phosphate phosphatase gene a6PP, and constructing a path for synthesizing D-psicose by taking D-glucose and D-xylose as substrates; the synthetic route of D-psicose is optimized by knocking out a D-glucose phosphorylation transport pathway gene ptsG, knocking out D-fructose-6-phosphokinase genes pfkA and pfkB, silencing a glucose-6-phosphate dehydrogenase gene zwf, overexpressing glutamate transhydrogenase genes gdh1 and gdh2, knocking out a UDP-glucose-4-epimerase gene galE and knocking out a transport protein key gene fryA in D-psicose; and finally, the optimal proportion of mixed sugar fermentation is explored, so that efficient synthesis of D-psicose from escherichia coli through mixed sugar fermentation of D-glucose and D-xylose is realized.

A food composition includes allulose having a concentration of about 60% to about 70% by weight, a cocoa product having a concentration of about 20% to about 30% by weight, and at least one natural plant resin having a concentration of about 0.37% to about 2.19% by weight. The at least one natural plant resin may be mastic gum and / or mastic powder. The food composition may further include a combination of plant-derived biominerals and / or antioxidants as active ingredients. A confectionary product made with the food composition is also disclosed.

The invention belongs to the technical field of gene engineering and protein engineering, and particularly relates to thermal-stable D-psicose 3-epimerase as well as a preparation method and application thereof. According to the invention, a series of D-psicose 3-epimerase DAE mutants are constructed, and six mutants which not only can retain good catalytic activity, but also have high thermal stability are obtained through screening. The catalytic temperature of the three mutants A19D / A223P / V241I is increased by 25 DEG C compared with that of a wild type, while the three mutants A19D / A223P / V241I still show the optimal thermal stability, the catalytic activity of the three mutants is improved by 17.0%, and the three mutants show good industrial suitability. The D-psicose 3-epimerase DAE mutant with improved thermal stability provided by the invention is beneficial to improving the production efficiency of the DAE in industrial application of D-psicose, and provides powerful industrial enzyme guarantee for large-scale and low-cost preparation of D-psicose.

A method for improving gut microbiota population in a subject by administering a composition comprising allulose, erythritol or a combination thereof. A method for increasing one or more colonic bacterial populations from the families Lachnospiraceae or Eubacteriaceae by administering a composition comprising allulose, erythritol or a combination thereof. A method for preventing, treating or ameliorating a disease in a subject by administering a composition comprising allulose, erythritol or a combination thereof. The disease may be one or more of metabolic syndrome, obesity, type 2 diabetes, insulin resistance, hyperlipoproteinemia, hyperuricemia, hepatic steatosis, hypercholesterolemia, hypertriglyceridemia, irritable bowel syndrome (IBS), colon cancer, allergy, non-alcoholic fatty liver disease, inflammatory bowel disease, cardiovascular disease, or inflammation. The bacterial population may be the species Anaerostipes hadrus, Blautia obeum, Anaerobutyricum hallii, Eubacterium rectale (Agathobacter rectalis), Eubacterium callanderi, Eubacterium limosum and Eubacterium maltosivorans. A composition comprising allulose, erythritol or a combination thereof and one or more colonic bacterial populations from the families Lachnospiraceae or Eubacteriaceae is also provided. The composition may in the form of a food composition.

The invention provides a healthy food, in particular to a hypoglycemic composition based on homology of medicine and food and gradient fermentation type prebiotics, which is a dry powder preparation and comprises a component A and a component B, the component A is a medicinal and edible component, and the component B is a prebiotic component; the component A is prepared from the following components in parts by mass: 2 to 15 parts of folium mori extract, 2 to 10 parts of bitter gourd extract, 2 to 20 parts of rhizoma dioscoreae extract, 1 to 10 parts of radix puerariae extract, 2 to 10 parts of fructus lycii extract, 0.5 to 5 parts of radix polygonati officinalis extract and 0.5 to 5 parts of rhizoma polygonati extract; the component B is prepared from 20 to 50 parts of resistant dextrin, 5 to 15 parts of xylooligosaccharide, 3 to 10 parts of inulin and 35 to 50 parts of D-psicose. The hypoglycemic activity of the traditional medicinal and edible materials is organically combined with the gradient fermentation type prebiotics, so that the hypoglycemic effect is realized by synergism of multiple action mechanisms, and the problems of single hypoglycemic mechanism and non-ideal blood sugar regulation effect of the existing product are solved.

To provide a binding syrup composition for formulating food products containing allulose and low sugar syrups.SOLUTION: The binding syrup composition overcomes limitations of allulose-containing products including product stickiness and failure to maintain shape and texture of the products. More specifically, the binding syrup compositions described herein contain low sugar syrups with low mono- and di-saccharide content in combination with allulose to impart binding and textural attributes to the allulose-containing food products that are comparable to full sugar products. Food products containing the allulose binding syrup compositions described herein and methods of producing the same are also provided. Beneficially, food products having reduced caloric and sugar content are provided when employing the allulose-containing binding syrup compositions described herein.SELECTED DRAWING: Figure 1

The invention belongs to the technical field of health-care products, and provides nano donkey-hide gelatin oral liquid and a preparation method thereof. The preparation method comprises the following steps: S1, crushing colla corii asini, mixing the crushed colla corii asini with a surfactant solution, and performing ultrasonic treatment to obtain coated colla corii asini particles; s2, mixing jujubes, Chinese wolfberry fruits and haws, crushing to obtain a mixture, mixing the mixture, the coated donkey-hide gelatin particles and water, and extracting to obtain an extracting solution; s3, concentrating the extracting solution to obtain a concentrated solution; s4, mixing the concentrated solution, psicose and astaxanthin, and performing nanoscale homogenization treatment to obtain the nano donkey-hide gelatin oral liquid. A layer of protective film is formed on the surface of the donkey-hide gelatin fine powder through a surface modification technology, so that the agglomeration phenomenon of the donkey-hide gelatin in the extraction process is effectively prevented. The donkey-hide gelatin particles are further refined through high-pressure homogenization treatment, so that the donkey-hide gelatin particles reach the nanoscale, and the solubility and bioavailability of the donkey-hide gelatin are remarkably improved.

Provided herein are compositions and methods relating to improved production of allulose by converting fructose to allulose using a allulose or psicose-3-epimerase from Brachyspira suanatina in the presence of base NaOH at 50 or 100mg / L.

The invention discloses a method for efficiently synthesizing D-psicose from cane sugar by escherichia coli through double PTS transfer. E.coliJM109 (DE3) is used as a chassis host bacterium, and a D-psicose synthesis path based on a sucrose PTS transport system is established through co-expression of alsE, a6PP, scrA and scrB genes; by introducing the glpX [K29A] gene, a carbon source is driven to flow from a D-fructose PTS transport system to a D-psicose synthesis path; through knockout of pfkA and rpiA genes and inhibition of expression of fbaA genes, an endogenous glycolysis pathway and a phosphopentose pathway are adjusted, and the carbon flow entering tricarboxylic acid circulation is adjusted, and finally, the purpose that the D-psicose is efficiently synthesized from sucrose by escherichia coli through double PTS transport is finally achieved. Genetic engineering modification is carried out on wild escherichia coli, D-psicose is efficiently synthesized from sucrose by using a sucrose PTS and fructose PTS system, and a new scheme is provided for synthesis of D-psicose.

The invention relates to the technical field of purification and concentration, in particular to a process for purifying and desalting psicose by an electrodialysis method. The electrodialysis method purification desalting process comprises the following steps: isomerizing a D-fructose solution to obtain a D-psicose solution; the D-psicose solution is decolored through activated carbon, and a decolored D-psicose solution is obtained; purifying and desalting the decolored D-psicose solution by adopting an electrodialysis method to obtain a purified and desalted D-psicose solution; enabling the purified and desalted D-psicose solution to pass through a chromatographic separation system to obtain a D-fructose mother solution and a D-psicose separation solution; the D-psicose separation solution is concentrated, cooled and crystallized, and the electrodialysis method purification desalting process is completed. The process for purifying and desalting the psicose by the electrodialysis method has the advantages of high efficiency, economy, stability and environment friendliness, and a new purification and desalting scheme is provided for production of the psicose.

The invention relates to the technical field of polysaccharide production, in particular to bacillus subtilis b1b-24-C and application of the bacillus subtilis b1b-24-C in fermentation co-production of D-psicose and isomaltooligosacharide. The bacillus subtilis b1b-24-C is preserved in the China General Microbiological Culture Collection Center (CGMCC), the preservation number is CGMCC NO.32594, the preservation date is November 13, 2024, and the address of the preservation institution is No.3, Yard 1, Beichen West Road, Chaoyang District, Beijing. The enzyme activity of the D-psicose 3-epimerase produced through fermentation of the bacillus subtilis is high, meanwhile, the stability, the conversion efficiency and the utilization efficiency of the enzyme can be effectively improved through immobilization of the enzyme, the production efficiency is improved, the production cost is remarkably reduced, and meanwhile, the method can also be used for co-producing an isomaltooligosacharide product.

The invention provides a group of recombinant Escherichia coli for forming D-psicose. The recombinant Escherichia coli comprises the following multiple modifications: (a) introducing and expressing a dTDP-glucose-3-epimerase gene, an NDP glycohydrolase gene, an allose-1 phosphate-isomerase gene and an acid phosphatase gene; and (b) enhancing the expression of the glucose phosphate mutase gene, the expression of the glucose 1-phosphate thymine transferase 1 gene and the expression of the glucose 1-phosphate thymine transferase 2 gene. The recombinant Escherichia coli capable of producing D-psicose at high yield is prepared, the yield of by-products is reduced while the yield of a target object is increased, the bottleneck problem in industrial production is solved, and the recombinant Escherichia coli can be used for mass production of D-psicose.

The invention belongs to the field of enzyme catalysis, and particularly relates to application of a multi-enzyme system / fusion protein in production of D-psicose, a production method of a fusion enzyme and application of the fusion enzyme in production of D-psicose and derivatives thereof from a carbohydrate source. More specifically, the present invention provides a simple, improved and cost-effective method for the production of D-psicose and derivatives thereof from carbohydrate sources from such fusion enzymes.

The present disclosure relates to microorganisms for psicose biosynthesis. Methods of producing the disclosed microorganisms and methods of producing psicose are also provided.

The invention relates to the technical field of beverages, and particularly discloses a high-protein beverage containing psicose and a preparation method of the high-protein beverage. The high-protein beverage containing psicose is prepared from the following raw materials in percentage by mass: 13 to 17 percent of supplementary protein, 4 to 5 percent of an emulsifier, 3.10 to 3.14 percent of a flavoring agent, 0.02 to 0.06 percent of a thickening agent, 0.005 to 0.015 percent of a stabilizer, 0.008 to 0.01 percent of a coloring agent, 0.04 to 0.08 percent of an enzyme preparation and the balance of water, the flavoring agent is prepared from D-psicose, erythritol, sucralose and stevioside. The D-psicose in the flavoring agent is extremely low in calorie, does not cause increase of blood sugar and insulin, and has a unique taste, and the erythritol, the sucralose and the stevioside are matched, so that the taste of sucrose is reduced on the premise of low calorie, and the problem of bitter taste of a sugar substitute beverage is solved, so that the flavor of the protein beverage is improved.

The invention relates to the technical field of gene engineering, in particular to a D-psicose-3-epimerase mutant and application of the D-psicose-3-epimerase mutant in synthesis of psicose. According to the present invention, the 59th site, the 106th site and the 188th site of the wild type D-psicose-3-epimerase derived from Brevibacillus thermophilus (Brevibacillus thermophilus) are subjected to simultaneous mutation to obtain the D-psicose-3-epimerase mutant, such that the efficiency of producing D-psicose by using fructose as the raw material is significantly improved, the reaction of catalyzing 500 g / L fructose to produce D-psicose is performed for 4 h, and the yield of the D-psicose is significantly improved; the conversion rate is up to 36.5%; according to the present invention, the coexpression binding enzyme strain is constructed by coupling glucose isomerase, such that the intermediate transfer efficiency and the enzyme stability are improved, the reaction for producing D-psicose through catalysis of 500 g / L glucose is performed for 6 h, and the conversion rate can achieve 30.5%; and the activity of the immobilized enzyme can still be kept at 80% after the immobilized enzyme is repeatedly used for 10 batches.

The invention discloses a method for synthesizing D-psicose through multi-enzyme co-immobilization cascade combination, and belongs to the field of enzyme engineering. According to the method provided by the invention, D-psicose-3-epimerase, L-rhamnokinase, polyphosphate kinase and prepared nitrilotriacetic acid modified magnetic nanoparticles are mixed and incubated to obtain the co-immobilized enzyme. According to the efficient co-immobilized enzyme provided by the invention, the stability is improved, the efficient co-immobilized enzyme is easily separated from an enzymolysis system, the repeated utilization of the immobilized enzyme can be realized, and the production cost is reduced. When the co-immobilized enzyme is applied to preparation of D-psicose, the raw material cost of an enzyme preparation is greatly reduced, and the co-immobilized enzyme has relatively high industrial application value.

The invention belongs to the field of escherichia coli metabolic processes, and particularly relates to a method for producing D-psicose from escherichia coli through glucose fermentation. Escherichia coli is used as a chassis host bacterium, a pgi gene, an SUMO-alsE fusion gene and an a6PP gene are subjected to overexpression at the same time, then a pfkA gene, a pfkB gene and a rpiA gene are knocked out in sequence, and a recombinant bacterium capable of producing D-psicose through glucose fermentation is obtained; the recombinant bacteria are used for fermentation, and glucose is converted to generate D-psicose.

The invention discloses a method for efficiently immobilizing enzyme and application of the method to preparation of D-psicose, and belongs to the field of enzyme engineering. According to the method provided by the invention, the immobilized D-psicose-3-epimerase is obtained by mixing and incubating the D-psicose-3-epimerase and prepared magnetic nanoparticles modified by nitrilotriacetic acid. According to the efficient immobilized D-psicose-3-epimerase provided by the invention, not only can the thermal stability of the D-psicose-3-epimerase be improved, but also the D-psicose-3-epimerase can be easily separated from an enzymolysis system, so that the reuse of the D-psicose-3-epimerase is realized, and the production cost is reduced. When the immobilized D-psicose-3-epimerase is applied to preparation of D-psicose, the raw material cost of an enzyme preparation is greatly reduced, and the immobilized D-psicose-3-epimerase has a relatively high industrial application value.

The invention relates to the technical field of immobilized enzymes, and provides DEAE (diethylaminoethanol)-cellulose immobilized D-psicose-3-epimerase as well as a preparation method and application thereof. The preparation method comprises the following steps: soaking DEAE-cellulose in water, then carrying out acid-alkali treatment, and then soaking the DEAE-cellulose in a phosphate buffer solution until the DEAE-cellulose is balanced to obtain activated DEAE-cellulose; the D-psicose-3-epimerase solution and a cross-linking agent are mixed for a cross-linking reaction, and a cross-linked enzyme solution is obtained; and mixing the cross-linked enzyme solution with the activated DEAE-cellulose, and carrying out immobilization, so as to obtain the DEAE-cellulose immobilized D-psicose-3-epimerase. The DEAE-cellulose immobilized D-psicose-3-epimerase prepared by the preparation method disclosed by the invention is good in stability and reusability, high in enzymatic activity, relatively high in conversion rate when catalyzing fructose isomerization to prepare psicose, and suitable for continuously converting fructose to generate psicose.

The invention belongs to the technical field of bioengineering and enzyme engineering, and discloses a strain for producing D-psicose-3-epimerase, thallus immobilized particles and a catalytic method, the strain is classified and named as Bacillus halotolans, the strain is preserved in China General Microbiological Culture Collection Center (CGMCC) on December 26, 2022, the preservation number is CGMCC No.26285, and the preservation number is CGMCC No.26285. The invention further discloses a preparation method of the D-psicose-3-epimerase for producing the D-psicose-3-epimerase for producing the D-psicose-3-epimerase for producing the D-psicose-3-epimerase for producing the D-psicose-3-epimerase. The thalli are loaded on the supporting carrier through the cross-linking agent, slow drying is achieved in the cross-linking drying process, and the obtained thalli immobilized particles have the advantages of being large in mechanical strength and insoluble in water.

The invention discloses a method for synthesizing D-psicose by multi-enzyme immobilized cascade catalysis of sucrose, and belongs to the technical field of food production. The method provided by the invention comprises the following steps: respectively immobilizing sucrose invertase, glucose isomerase and epimerase by utilizing protein affinity immobilization purification magnetic beads to prepare immobilized enzyme, carrying out enzymatic reaction by taking sucrose as a substrate, and converting the sucrose into D-psicose step by step. Experimental results show that the method provided by the invention can effectively convert cane sugar, glucose and fructose which are easy to absorb into D-psicose which is difficult to absorb; after the enzymatic reaction, the immobilized enzyme can be effectively recovered through rapid separation and can be reused, so that the production cost is saved. The invention provides a low-cost and high-efficiency production method for the production of D-psicose, and the method has a wide application prospect.