75 results about "Tagatose" patented technology

The invention discloses L-arabinose isomerase, engineering bacteria and application, the amino acid sequence of the L-arabinose isomerase is shown as SEQ ID NO: 3, and the gene sequence for coding the L-arabinose isomerase is shown as SEQ ID NO: 2. On the basis of a genome of a Peribacillussp.S4 strain, a gene for coding the L-arabinose isomerase is excavated, and a stable prokaryotic expression system is constructed by performing codon optimization on the gene, so that the large-scale controllable production of the L-arabinose isomerase is realized, the yield of the enzyme is remarkably increased, the production cost of the enzyme is reduced, and the method is suitable for industrial production. A stable and economical enzyme source is provided for the production of D-tagatose; the L-arabinose isomerase expressed by the constructed engineering bacteria can significantly improve the yield of D-tagatose, and industrialization of D-tagatose is facilitated.

Disclosed herein are formulations (including sweet proteins and rare sugars) for improving the sweetness of low glycemic index rare sugars without altering the texture and flavor of the rare sugars and methods for improving the sweetness of rare sugars. More specifically, the present invention discloses methods for improving the sweetness of rare sugars without altering the sweetness profile, texture and flavor of the primary sugars. The invention also discloses the addition of Brazitame protein with liquid rare sugars at different temperatures during the synthesis of the rare sugars, before crystallization or before or after caramelization of the rare sugars, to increase sweetness. The Brazilian sweet protein increases the sweetness of rare sugars, but is not limited to D-psicose, D-tagatose, D-allose, isomaltulose, trehalose, sorbose, pinose, leucobiose and the like. The invention also provides for the evaluation of non-nutritional sweeteners (such as aspartame, acesulfame, sodium cyclamate, neotame, saccharin, sucralose, stevioside, etc.), as each has a limitation of taste quality if used with rare sugars. However, the use of Brazilian sweet protein does not alter the flavor and texture of rare sugars, and the taste profile matches sucrose.

The present invention relates to a use of an enzyme belonging to the aldolase group and comprising a polypeptide having at least 30% identity with an amino acid sequence selected from SEQ ID NO: 1 to SEQ ID NO: 4, for stereoselectively preparing D-tagatose-1,6-bisphosphate (TBP) or D-tagatose-1-phosphate. The present invention also relates to a method for preparing D-tagatose-1,6-bisphosphate (TBP) or D-tagatose-1-phosphate, comprising a step of reacting, in a suitable reaction medium, dihydroxyacetone phosphate (DHAP) or at least an isomer thereof or analog thereof, and optionally D-glyceraldehyde, with an enzyme belonging to the aldolase group, said enzyme comprising a polypeptide having at least 30% identity with an amino acid sequence selected from SEQ ID NO: 1 to SEQ ID NO: 4. Finally, the present invention relates to a process for preparing D-tagatose.

The invention belongs to the technical field of food coloring, and particularly relates to a compound sweetening agent capable of coloring at low temperature for food as well as a preparation method and application of the compound sweetening agent. The D-psicose and tagatose chewable tablets are prepared from the following raw materials in parts by mass: 15 to 20 parts of D-psicose, 1 to 5 parts of tagatose, 2 to 8 parts of D-xylose, 20 to 25 parts of xylitol, 30 to 35 parts of solid maltitol, 30 to 35 parts of liquid maltitol, 10 to 14 parts of polydextrose and 0.5 to 1.5 parts of stevioside. The sweetening agent with a coloring function is perfectly combined with other sugar-free sweetening agents, so that function synergy is realized, food can quickly generate good color and luster in a low-temperature state, and the nutrition of the food is prevented from being lost.

The present application relates to a fructose-4-epimerase variant exhibiting tagatose conversion activity and a method for preparing tagatose using the same.

To provide an immobilized enzyme composition for hexose production or an improved process for hexose production. [Solution] The present invention relates to an immobilized enzyme composition for the preparation of hexoses. Examples of hexoses include tagatose, psicose, fructose, allose, mannose, galactose, altrose, talose, sorbose, gross, idose, and inositol. The present invention also relates to an enzymatic process for preparing hexoses from sugars by contacting starch derivatives with the immobilized enzyme composition of the present invention.

The invention relates to the technical field of biology, in particular to epimerase for synthesizing D-tagatose and application. Epimerase producing mutation of 100th or 125th or 127th or 131 or 268th or 270th or 271th or 308th or 339th or 340th or 342th or 366th or 402th or 437th in amino acid sequence as shown in SEQ ID NO.7 mutation at the 440th site; through the mode, the epimerase shows excellent epimerization activity at the fourth carbon position of D-fructose, can efficiently convert D-fructose into D-tagatose, and is beneficial to improving the synthesis efficiency of D-tagatose.

The utility model discloses an ion exchange device for tagatose production, which relates to the technical field of ion exchange and comprises a base, a fixing support is fixedly connected to the upper end of the base, and four fixing rods are fixedly connected to the side wall of the fixing support. The end, away from the fixing support, of the fixing rod is fixedly connected with a first exchange assembly, a second exchange assembly, a third exchange assembly and a fourth exchange assembly respectively, and the first exchange assembly, the second exchange assembly, the third exchange assembly and the fourth exchange assembly each comprise an installation cylinder. The position of the inner cylinder in the mounting cylinder can be conveniently adjusted, so that the height of the whole ion exchange assembly can be flexibly adjusted, the device can meet the mounting requirements of equipment with different heights, the applicability and the flexibility of the device are greatly enhanced, and in the mounting or dismounting process, only the limiting cylinder needs to be simply rotated, and the mounting and dismounting are convenient. Therefore, the pipeline can be quickly spliced with or detached from the liquid outlet at the lower end of the mounting cylinder and the liquid inlet at the upper end of the inner cylinder.

The present application relates to the technical field of biotechnology, and particularly relates to a tagatose-6-phosphate phosphatase mutant and a method for synthesizing tagatose from scratch. The method provided by the present application is a one-pot method for biosynthesizing D-tagatose by using starch or dextrin as a substrate, adopting a multi-enzyme cascade reaction system composed of a tagatose-6-phosphate phosphatase mutant, a glycogen-debranching enzyme, an alpha-glucan phosphorylase, a phosphoglucomutase, a glucose-6-phosphate isomerase, a D-tagatose-6-phosphate-3-epimerase and a 4-alpha-glucan transferase. The method can prepare tagatose from ordinary and inexpensive starting materials (starch or dextrin) at a high yield, improves the overall conversion rate of the system and the final yield of tagatose, provides a new technical approach for realizing low-cost and green production of tagatose, and has the advantages of high yield, low cost and being more suitable for industrial production.

The application belongs to the technical field of biology and specifically relates to a method for synthesizing D-tagatose through multi-enzyme cascade catalysis, which uses lactose as a substrate and utilizes beta-galactoside enzyme, L-arabinose isomerase, glucose isomerase, fructokinase, tagatose-1,6-diphosphate aldolase, polyphosphate kinase and phosphatase for synchronous cascade catalysis to synthesize D-tagatose. The method improves the conversion rate of D-tagatose by continuously converting the intermediate product D-glucose into D-tagatose, provides a new method for synthesizing D-tagatose from lactose, and provides certain theoretical basis and technical support for realizing the industrialized production of high-value-added D-tagatose.

The invention discloses a high-induction-activity promoter derived from a tagatose operon of bacillus licheniformis, and belongs to the field of gene engineering. The promoter PfruK2 capable of being induced by a carbon source in a PTS (Pleurotropin Tyrosine Sequence) way is screened, the induced carbon substrate spectrum capable of being responded by the promoter is wide, the promoter is not affected by a glucose-mediated CCR effect, the induction intensity is high, and the induction peak value is improved by more than 50% compared with that of a quorum sensing strong promoter PLan.

The invention relates to the technical field of food, and provides a rare sugar composition and a preparation method thereof, and the rare sugar composition comprises tagatose and psicose in a mass ratio of (40-98): (2-10). The preparation method comprises the following steps: by taking lactose hydrolysate as a raw material, adding calcium hydroxide into the lactose hydrolysate for reaction, wherein the reaction product comprises the rare sugar composition. According to the rare sugar composition, the rare sugar is high in purity and clean and pure in flavor, the sweetness and taste of the rare sugar are close to those of cane sugar, the rare sugar composition can serve as a substitute of cane sugar, according to the preparation method of the rare sugar composition, lactose serves as a raw material and is isomerized into tagatose and psicose, the conversion rates of the tagatose and the psicose can reach 40% and 4% respectively, reaction conditions are mild, the preparation process is simple and controllable, and the preparation cost is low. And the production process has flexibility, rare sugar mixtures with different components and different specifications can be obtained by combining separation and purification process adjustment, different production processes can be selected according to actual requirements of products, and the method has a good industrial application prospect.

The invention relates to a method for synthesizing D-tagatose and application of the D-tagatose, the method comprises the following steps: L-arabinose isomerase and D-galactose are mixed, and the amino acid sequence of the L-arabinose isomerase comprises a sequence as shown in SEQ ID No.1. The enzyme has good soluble expression in host bacteria, the expressed enzyme can stably catalyze conversion of D-galactose into D-tagatose, and the catalytic efficiency is high.

The utility model provides a tagatose centrifugal spray dryer, which relates to the technical field of tagatose production, and comprises a tagatose centrifugal drying box, a support plate I is slidably connected in the tagatose centrifugal drying box, sieve pores are uniformly formed in the support plate I, universal wheels are fixedly connected to the lower surface of the support plate I, and the universal wheels are fixedly connected to the lower surface of the support plate II. A second supporting plate and an annular supporting plate are fixedly connected to the inner wall of the tagatose centrifugal drying box, and a trapezoidal cushion block is fixedly connected to the upper surface of the annular supporting plate. Compared with the prior art, the tagatose particle collecting device has the advantages that tagatose particles can be directly collected, the efficiency is higher, and meanwhile, the tagatose particles are prevented from flying out along with hot air of the air heater to cause waste; according to the tagatose spray drying device, the situation that the normal use of the tagatose is affected due to the fact that the tagatose particles cannot be completely dried and the tagatose is prone to caking and mildewing in the storage process is avoided, and the long scraper turns over and stirs the tagatose spray, so that the tagatose spray drying efficiency is higher.

This invention belongs to the field of biosynthesis technology and relates to a method for producing D-tagatose under nickel-free conditions and its application. The method includes: mixing tagatose 4-epimerase with a substrate solution, reacting the mixture, and collecting the supernatant by centrifugation to obtain the product. The substrate solution is prepared from D-fructose, glycine, sodium hydroxide, and water. This invention uses tagatose 4-epimerase to catalyze the production of D-tagatose, and the reaction system does not contain nickel ions or other heavy metal ions, thus avoiding the safety hazards caused by nickel residues. This method has a wider range of applications and higher safety.

The invention relates to an enzyme activity improved tagatose-4-epimerase mutant and application thereof, molecular modification is performed on thermoprotei archaeon sourced tagatose-4-epimerase (T4Ease), site-specific mutagenesis is performed on 56th serine of an amino acid sequence as shown in SEQ ID No.2 to obtain alanine, a mutant S56A is obtained, the optimum pH of the mutant S56A is 7.0, the optimum reaction temperature is 90 DEG C, and the enzyme activity improved tagatose-4-epimerase (T4Ease) can be obtained after the mutant S56A is subjected to enzyme activity improvement, so that the enzyme activity improved tagatose-4-epimerase (T4Ease) can be obtained. Compared with a wild type, no obvious change exists; the tagatose-4-epimerase has the advantages that the tagatose-4-epimerase has high activity, the activity of the tagatose-4-epimerase is 2.84 U / mg and is increased by 260% compared with that of a wild type, an excellent catalyst is provided for tagatose production in industry, the production cost of tagatose is reduced, and a foundation is laid for research on tagatose-4-epimerase and tagatose.

The invention discloses a method for producing D-tagatose with high efficiency and low cost. According to the invention, a double-enzyme cascade engineering strain B.subtilis WB800N-pHT01-araA-lacZ, which can be used for simultaneously expressing a beta-galactosidase gene lacZ and an L-arabinose isomerase gene araA, is constructed, and the double-enzyme cascade engineering strain B.subtilis WB800N-pHT01-araA-lacZ is constructed; culturing the engineering strain, centrifugally collecting thalli, resuspending the collected thalli by using a substrate solution containing whey powder (lactose), and reacting at constant temperature; and finally, centrifuging the reaction liquid after the reaction is finished, taking supernate, filtering the supernate through a 0.22 m water system small filter, and determining the D-tagatose in the supernate by high performance liquid chromatography, the yield of the D-tagatose being up to 77.5 g / L. The method provided by the invention can realize efficient reutilization of the milk product byproduct whey powder, and has the advantages of simple operation method, mild reaction conditions, high efficiency, low cost and the like.

The present invention relates to a process for preparing tagatose from a biomass or any carbohydrate source derived sugar. The present invention includes methods for producing tagatose using a range of enzymes to convert biomass, such as, but not limited to, starch, maltose, maltodextrin, cellulose, sucrose from juice, and monosaccharides, such as, but not limited to, glucose and / or fructose, etc. The invention also focuses on the use of enzymes alone and / or fused with enzymes involved in successive steps for the economical, efficient conversion of biomass sugars into tagatose.

The invention discloses recombinant escherichia coli for producing D-tagatose by using redox enzyme driven by cofactor regeneration as well as a construction method and application of the recombinant escherichia coli, and belongs to the technical field of biological engineering. The method comprises the following steps: introducing xylose reductase xyrB, glucose dehydrogenase Gox2015, galactitol dehydrogenase RlGDH mutant T193G / G98C and water-producing NADH oxidase SpNox into escherichia coli, so as to construct recombinant escherichia coli; according to the method disclosed by the invention, a way for synthesizing the D-tagatose by regenerating and driving oxidoreductase through cofactors is designed and constructed, and lactose in whey can be completely converted into the D-tagatose and sodium gluconate by combining the way with beta-galactosidase, so that high-valued utilization of a dairy product processing by-product whey is realized.

The application discloses an aldose reductase mutant and application thereof in production of D-tagatose, and belongs to the technical field of genetic engineering. The aldose reductase mutant has high catalytic activity, can be coupled with galactitol 2-dehydrogenase, realizes NADH cyclic regeneration, and greatly reduces the preparation cost of D-tagatose. The aldose reductase mutant is used to prepare D-tagatose, 98.2g / L of D-tagatose can be obtained within 5h, and the yield is as high as 98.2%, which is superior to the conversion effect of wild type and other mutant enzymes, so that the aldose reductase mutant has a good industrial application prospect.

The invention relates to a protein scaffold mediated multienzyme cascade system and application thereof in preparation of D-tagatose. The protein scaffold mediated multi-enzyme cascade system provided by the invention comprises fructokinase, D-tagatose-6-phosphate 4-epimerase and D-tagatose-6-phosphate phosphatase, and the protein scaffold mediated multi-enzyme cascade system comprises fructokinase, D-tagatose-6-phosphate 4-epimerase and D-tagatose-6-phosphate phosphatase, the D-tagatose-6-phosphoric acid 4-epimerase and the D-tagatose-6-phosphoric acid phosphatase are immobilized on the protein support SH3, and the D-tagatose-6-phosphoric acid 4-epimerase is immobilized on the protein support SH3. According to the system, a plurality of key enzyme spaces in a reaction path are positioned on a protein scaffold through a protein-protein interaction structural domain (SH3), so that a substrate channel and a spatial proximity effect are enhanced, and the yield of D-tagatose is increased. According to the method disclosed by the invention, the yield of the D-tagatose is 3.2-7.7 times that of the original D-tagatose by optimizing reaction conditions.

The present invention provides a composition for promoting the secretion of glucagon-like peptide-1, its preparation method, and application, relating to the technical fields of food and health food. The composition comprises polygonatum powder, ampelopsis glauca leaf powder, tagatose, fig powder, and Ilex paraguariensis leaf extract. The composition for promoting the secretion of glucagon-like peptide-1 of the present invention can effectively promote the secretion of GLP-1, lower blood sugar, and maintain healthy blood sugar levels.

The invention discloses a D-tagatose-3-epimerase mutant and application thereof, the D-tagatose-3-epimerase mutant has a single-point mutation or a multi-point mutation in the 45th mutation, the 48th mutation, the 50th mutation, the 80th mutation, the 93th mutation, the 98th mutation and the 144th mutation relative to an amino acid sequence SEQ ID NO.1 of a wild type D-tagatose-3-epimerase, and the D-tagatose-3-epimerase mutant has a single-point mutation or a multi-point mutation in the 45th mutation, the 48th mutation, the 50th mutation, the 80th mutation, the 93th mutation, the 98th mutation and the 144th mutation. The invention also provides a corresponding coding gene, a recombinant vector, a genetically engineered bacterium, a biocatalyst and application in preparation of rare sugars. The invention develops the D-tagatose-3-epimerase mutant which has stronger adaptability with glucose isomerase and is more stable in a cascade reaction, is beneficial to improving the efficiency of reaction for preparing rare sugar by using xylose, can simultaneously consider higher substrate concentration and D-xylose conversion rate, and reduces the production cost of the product.

The invention discloses tagatose-containing flavor biscuits with a low glycemic index. The tagatose-containing flavor biscuits are mainly prepared from the following components in parts by weight: 55-70 parts of whole wheat flour, 7-15 parts of wheat bran, 15-30 parts of nutritional sweet substances, 30-50 parts of grease, 5-15 parts of bean flour, 3-7 parts of tartary buckwheat flour, 1-4 parts of resistant dextrin, 0.5-3 parts of milk powder, 0.2-2 parts of natural plant extracts and 0.5-2 parts of additives. Meanwhile, the invention provides a corresponding preparation method. According to the tagatose-containing flavored biscuit with the low glycemic index, sugar alcohol is replaced with tagatose, on one hand, the glycemic index is reduced, on the other hand, the color and flavor of the biscuit are improved, in combination with an enzyme inhibition mechanism of the mulberry leaf extract or the white kidney bean extract, the starch hydrolysis rate can be reduced, and the content of dietary fibers in the biscuit is high; the perfect unification of the function and the taste of the biscuit product is realized.

The invention discloses bread capable of regulating and controlling protein accumulation behaviors through tagatose coupled vital gluten and biologically modified dietary fibers to achieve low GI and a preparation method of the bread, and relates to the technical field of baking. Kneading dough; making dough; performing fermentation; performing baking; the raw materials of the compound functional sugar substitute bread not containing the butter are evenly mixed, water is added, the mixture is kneaded into dough, the dough is whipped, the whipping is divided into high-speed whipping and low-speed whipping, and the tagatose is coupled with the vital gluten and the biologically modified dietary fibers to regulate and control the protein accumulation behavior, so that the low-GI bread is achieved. By replacing 60% or more of cane sugar with tagatose, replacing 15% or more of high-gluten flour with biologically modified dietary fiber and replacing 7% or more of high-gluten flour with vital gluten for bread making, the bread made by the method has high specific volume and good flavor, the use amount of cane sugar in bread making is greatly reduced, and the bread is more suitable for bread making. And the use amount of the high-gluten wheat flour is reduced to a certain extent.

The application discloses a method for producing D-tagatose by a three-enzyme cascade method, and belongs to the field of biotechnology. In the method, fructose is used as a substrate, a reaction system containing metal ions and ATP is used, fructose kinase FRK derived from Clostridium acetobutylicm, D-tagatose 6-phosphate 4-epimerase GatZ derived from Caldilinea aerophila DSM 14535 and D-tagatose-6-phosphate phosphatase MmPase derived from Methanothermobacter marburgensis are used to produce D-tagatose. The yield of D-tagatose is 2.7-9 times of the original yield by optimizing the temperature, the type and the concentration of the metal ions.

The invention discloses a tagatose-4-epimerase and an application of the tagatose-4-epimerase in preparation of D-tagatose. The amino acid sequence of the tagatose-4-epimerase comprises a sequence as shown in SEQ ID NO. 1 to SEQ ID NO. 9. The invention also discloses a preparation method of the tagatose-4-epimerase. The tagatose-4-epimerase disclosed by the invention is used as a catalyst to catalyze D-fructose, and the yield of D-tagatose can reach more than 30%.

The application belongs to the technical field of biotechnology, and particularly relates to a recombinant Escherichia coli and application of the recombinant Escherichia coli in simultaneous production of D-mannose, D-psicose and D-tagatose. Specifically, the application provides a recombinant Escherichia coli, the strain of which simultaneously expresses five key enzymes, can use cheap glucose as a substrate, and can simultaneously synthesize D-mannose, D-psicose and D-tagatose in a single reaction system through a multistage enzyme cascade reaction, so that a one-pot three-sugar production mode is realized. In the technical scheme, PPGK can use polyphosphate to replace ATP to provide a phosphate group, so that the addition of an expensive auxiliary factor is avoided, and the production cost is significantly reduced. Meanwhile, the three products are simultaneously generated in a single system, so that subsequent separation and purification steps are simplified, and the application has a good industrial application prospect.

Disclosed are components and methods for preparing tagatose from galactose via isomerization reactions using engineered components. The engineered components include microbial cells and methods for preparing microbial cells that have been engineered to catalyze isomerization of galactose to tagatose, in which the microbial cells express cytoplasmically an exogenous L-arabinose isomerase enzyme. The disclosed microbial cells may further be modified for use in methods for preparing tagatose from galactose via isomerization reactions where the microbial cells are treated with reagents that permeabilize the cells. The disclosed methods enable isomerization reactions of galactose to tagatose at relatively high rates, high conversions, and elevated temperatures.