135 results about "Steviol glycoside" patented technology

The invention belongs to the technical field of biosynthesis, and particularly relates to a method for regulating and controlling stevioside production through a UDPG synthesis route. According to the invention, a high-efficiency stevioside biosynthesis system is constructed through systematic engineering modification: in the aspect of chassis cell optimization, transcription factors (AtWRKY18, AtWRKY40 and AtMYC2) for regulating and controlling MEP pathway and key genes (dxs and / or dxr) of the MEP pathway are over-expressed, so that supply of terpene precursors is enhanced; and a heterologous MVA pathway (over-expression T7-atoB-mvaS-mvaE-mvK / mvKmut-pmK-mvaD-idi) with a modular design is introduced, so that sufficient supply of the terpenoid precursor is realized. Meanwhile, the intracellular concentration of the UDPG is increased by systematically enhancing a UDPG synthesis pathway (knocking out ugd, glgc, ushA, agp, deoA, tdk, udp, or thrA, and overexpressing galU, pgm, pyrE, pyrH, ugpA, or prs), so that the production capacity of the stevioside is remarkably improved.

The invention belongs to the technical field of biosynthesis, and particularly relates to a method for regulating and controlling stevioside production by improving the utilization rate of a carbon source. According to the invention, a high-efficiency stevioside biosynthesis system is constructed through systematic engineering modification: in the aspect of chassis cell optimization, transcription factors (AtWRKY18, AtWRKY40 and AtMYC2) for regulating and controlling MEP pathway and key genes (dxs and / or dxr) of the MEP pathway are over-expressed, so that supply of terpene precursors is enhanced; and a heterologous MVA pathway (over-expression T7-atoB-mvaS-mvaE-mvK / mvKmut-pmK-mvaD-idi) with a modular design is introduced, so that sufficient supply of the terpenoid precursor is realized. Meanwhile, by knocking out related genes and bypass metabolism genes (mgsA, iclR, menA or adhE) synthesized by organic acid, a glucose transport and utilization system (fnr, fadR, ppc, zwf or pgi is knocked out, and ACS, fbaA, tpiA, glf, galP or ptsG is overexpressed, so that the utilization rate of a carbon source is further improved, and the production capacity of stevioside is remarkably improved.

The invention relates to a stevioside composition, which comprises at least one stevioside and at least one of siamenoside I, mogroside V, mogroside III-E and mogroside II-E, and is characterized in that the stevioside composition comprises at least one stevioside and at least one of siamenoside I, mogroside V, mogroside III-E and mogroside II-E; wherein the stevioside has a higher solubility in the composition than in an equivalent composition lacking siamenoside I, mogroside V, mogroside III-E, and mogroside II-E. The invention also relates to a method for preparing the stevioside composition. The composition may be an aqueous solution.

The invention relates to an engineered glycosyltransferase and a steviol glycoside glucosylation method. The present invention provides engineered glycosyltransferases (GTs), polypeptides having GT activity and polynucleotides encoding the enzymes, as well as vectors and host cells comprising the polynucleotides and polypeptides. The present invention provides engineered sucrose synthases (SuS), polypeptides having SuS activity and polynucleotides encoding the enzymes, as well as vectors and host cells comprising the polynucleotides and polypeptides. The invention also provides compositions comprising the GT enzymes and methods of using the engineered GT enzymes to prepare products having beta-glucose ligation. The present invention also provides compositions and methods for producing rebaudioside (e.g., rebaudioside M, rebaudioside A, rebaudioside I, and rebaudioside D). The invention also provides compositions comprising the SuS enzymes and methods of using the same. Methods for producing a GT enzyme and a SuS enzyme are also provided.

The present invention is expected to develop a novel alcoholic beverage having an ideal aroma effect. The present invention relates to an alcoholic beverage, which is characterized in that the alcoholic beverage contains steviol glycoside, and the protein content is 20-7000 mg / L.

The invention relates to the technical field of biological catalysis engineering, in particular to a method for improving the solubility of stevioside Reb M and Reb D through enzyme catalysis modification, which comprises the following steps: dissolving Reb M and Reb D with the purity of more than or equal to 90% in a buffer solution with the pH value of 4.0-8.0, adding a non-starch glycosyl donor and composite glycosyl transferase according to the enzyme-substrate mass ratio of 0.05-0.5, and optimizing the enzyme addition sequence to realize specific site modification; reacting for 6-24 hours under the conditions that the pH is 5.5-6.0 and the temperature is 60-85 DEG C, and controlling the proportion of DP2-3 to be 60-80%; hPLC sampling is carried out every 4-6 hours, and the unreacted substrate is less than or equal to 20%; the solubility of the product is greater than or equal to 25g / L, and the sweet taste of the product is pure. According to the method, the solubility of Reb M / Reb D is improved, the structure of a directional glycosylation controlled product is realized, and pure sweetness is reserved; the reaction is mild and controllable, enzyme inactivation is simple and free of residues, industrialization is easy, and stevioside application upgrading is promoted.

The present invention discloses a method for producing a target stevioside. According to the method for producing the target stevioside, the distribution change amount of the target stevioside reaches 90% or above within 2 hours, so that a precipitate containing the target stevioside is formed. The target stevioside is rebaudioside D and / or rebaudioside M. The target stevioside is rebaudioside M.

The application belongs to the technical field of steviol glycoside production, and discloses a method for preparing steviol glycoside single components by using low total glycoside mother liquor sugar, which comprises the following steps: dissolving the low total glycoside mother liquor sugar in 80-95% methanol solution, crystallizing, filtering to obtain mother liquor and filter cake, treating the filter cake with 40-50% methanol solution, stirring and crystallizing, filtering to obtain mother liquor and filter cake, drying the filter cake to obtain pure rebaudioside A; using macroporous adsorption resin to separate the two mother liquors obtained in the previous step, using 30% ethanol solution to separate the glycosides adsorbed in the macroporous adsorption resin, playing a separating role, using 50% ethanol solution added with 1‰ oil tea saponin to resolve the macroporous adsorption resin, crystallizing and recrystallizing the resolution liquid, drying the filter cake to obtain rebaudioside C, and combining the two mother liquors obtained, removing impurities, and using high-pressure chromatography to collect resolution liquid containing rebaudioside F, and drying the resolution liquid to obtain rebaudioside F. The method is simple and effective, and greatly improves the reutilization rate of low total glycoside mother liquor sugar.

Provided herein are variant uridine-5'-diphosphate glycosyltransferase polypeptides capable of producing steviol glycosides, yeast cells capable of producing steviol glycosides, and methods of making such cells. Also provided are fermentation compositions including the disclosed host cells, and related methods of producing and recovering steviol glycosides generated by the yeast cells.

Compositions and consumables comprising certain sweeteners and at least one flavonoid of Formula I are provided herein, wherein the at least one sweetener is selected from certain steviol glycoside and / or mogroside sweeteners. The at least one flavonoid enhances the sweetness of the consumable and / or modulates one or more taste attributes to make the consumable taste more like a sucrose-sweetened consumable. Methods of enhancing the sweetness of a consumable, methods of making a consumable taste more like a sucrose-sweetened consumable and methods of preparing consumables are also detailed herein.

The present invention relates to a novel Lactobacillus marzei CJST01 strain having excellent steviol glycoside transglycosylation activity, and a method for producing a steviol glycoside using the same. Compared with the known Lactobacillus margaritae DSM20444 strain capable of generating the steviol glycoside transglycosylation effect, the novel Lactobacillus margaritae CJST01 strain has excellent steviol glycoside transglycosylation activity, so that the enzyme reaction time in the production process is shortened. The steviol glycosides produced by using the strain have the advantage of a better taste quality or flavor than alpha-1, 4-linked steviol glycosides and rebaudioside M. In addition, the transglycosylated rebaudioside A produced by using the Lactobacillus margaritae CJST01 strain has a reduced foreign taste and flavor, and excellent solubility.

A novel steviol glycoside has been demanded. According to one aspect of the present invention, there is provided a compound represented by formula (1) (wherein (i) R1 represents Xyl(1-2)Glc1- and R2 represents Glc(1-2)Glc1-; or (ii) R1 represents Glc(1-2)Glc1- and R2 represents Glc(1-2)[Xyl(1-3)]Glc1- wherein Glc represents glucose and Xyl represents xylose), or a salt or hydrate thereof.

This invention discloses a method for recovering a mixture of steviol glycosides and rebaudioside B from stevia mother liquor, comprising the following steps: dissolving stevia mother liquor in purified water to obtain a stevia mother liquor solution; adding a pH adjuster to the stevia mother liquor solution to adjust the pH to 6.5-7.0, obtaining a solution to be treated; filtering the solution to be treated once using a hollow fiber membrane, and washing the retentate with purified water to obtain a retentate and a permeate; subjecting the permeate to vacuum concentration and spray drying sequentially to obtain a mixture of steviol glycosides; heating the retentate and adjusting the pH to 4.5-5.0, performing sedimentation treatment, filtering while hot, and drying the filter cake to obtain the rebaudioside B product. This invention uses stevia mother liquor as raw material to produce a mixture of steviol glycosides with high total glycoside content, rebaudioside B, and feed additives, improving the economic value of stevia mother liquor. The process is simple, easy to operate, and suitable for large-scale industrial production, with significant economic and social benefits.

This invention relates to the field of biosynthesis technology, and particularly to engineered yeast strains and their application in the total fermentation production of steviol glycosides. This invention utilizes site-directed mutagenesis to mutate wild-type kaurenoic acid 13-hydroxylase, obtaining the G481L / Q159L mutant. This mutant is then applied to the production of steviol or steviol glycosides, constructing a steviol or steviol glycoside synthesis pathway in the *Saccharomyces cerevisiae* host to achieve efficient production of steviol or steviol glycosides. Simultaneously, by enhancing the level of diterpene precursor synthesis genes in chassis cells (MVA pathway, acetyl-CoA, GGPP, transport proteins, UDPG pathway), the yield of steviol glycosides is further increased, reducing costs for industrial production.

The present invention relates to a UDP-glucosyltransferase variant, a fusion enzyme of UDP-glucosyltransferase variants, and a use thereof for producing steviol glycoside. The UDP-glucosyltransferase variant and the fusion enzyme of UDP-glucosyltransferase variants according to the present invention have improved enzymatic activity. In addition, the fusion enzyme of UDP-glucosyltransferase variants has further improved enzymatic activity compared to when each variant is used individually. Accordingly, the UDP-glucosyltransferase variant and the UDP-glucosyltransferase variant fusion enzyme according to the present invention can be widely applied in the field of steviol glycoside synthesis, and have excellent commercial value and significance in that production efficiency can be increased and production costs can be reduced.

The invention discloses an apple polyphenol-stevioside composite flavoring agent, and belongs to the technical field of food processing. The compound flavoring agent is prepared from the following raw materials in parts by weight: 110 to 120 parts of maltitol, 4 to 7 parts of stevioside and 7 to 10 parts of apple polyphenol. According to the compound flavoring agent disclosed by the invention, through the synergistic effect of the apple polyphenol and the stevioside, the mouth feel defects that the stevioside is obvious in bitter taste and lags behind the sweet taste are effectively overcome, and the mouth feel experience is remarkably improved. And the product has an antioxidant function, is endowed with a healthy additional value, and conforms to the requirements of the market on functional food additives. Meanwhile, the preparation process is optimized, high uniformity and stability of the product are ensured, the product can keep excellent performance in multiple scenes such as beverages and baked food, the problem that the application scene of the prior art is limited is solved, and a new solution is provided for developing broad-spectrum food additives with excellent taste and multiple functions.

The utility model discloses a stevioside production soaking device which comprises a stevioside production soaking device body, and a sealing cover is fixedly mounted at the top of the stevioside production soaking device body. According to the stevioside production soaking device, stevioside is placed in the stevioside production soaking device body, then a user adds clean water and starts the motor, the output end of the motor drives the worm to rotate, the worm rotates to drive the worm gear to rotate, the worm gear rotates to drive the supporting rod to rotate, and the supporting rod rotates to drive the rotating disc to rotate; the rotating disc rotates to drive the connecting rod to rotate, the connecting rod rotates to pull the moving rod to move, the moving rod is made to turn over in a reciprocating mode with the fixing frame as the circle center, the moving rod drives the steel rope to move up and down, the steel rope can drive the pressurizing plate to move up and down, a stevioside raw material can be extruded, and the stevioside raw material and water can be fully mixed conveniently. And an existing direct soaking mode is replaced.

A solubilized steviol glycoside composition including one or more steviol glycosides and one or more steviol glycoside solubility enhancers can be used as a sweetener composition to sweeten other compositions (sweetenable compositions) such as foods, beverages, medicines, oral hygiene compositions, pharmaceuticals, nutraceuticals, and the like.

A sweetener composition is provided that includes a sweetening amount of a stevioside rebaudioside (EM) (Reb EM). The Reb EM may be present at a concentration of 0.02 wt% to 100 wt% by weight of the composition. The Reb EM may be included in a food or beverage product or concentrate. The beverage product or concentrate may comprise from about 1 ppm to about 50,000 ppm of Reb EM. The beverage product or concentrate may comprise from about 50 ppm to about 500,000 ppm of total stevioside. The isolated and purified Reb EM compound may have a purity of from about 95% to about 99.9%. Methods of sweetening a food or beverage product using Reb EM are also provided.

This invention discloses a glycosyltransferase mutant and its application in the synthesis of rebaudioside. Based on the amino acid sequence of the glycosyltransferase shown in SEQ ID NO:1, this invention performs single-point and multi-point mutations to obtain mutants with enhanced catalytic activity. The catalytic activity, substrate specificity, and / or substrate specificity of the glycosyltransferase mutant are altered; mutations at specific sites can significantly improve the enzyme's catalytic activity for specific substrates. The mutant enzyme is obtained by inducing expression and purifying the protein from the obtained mutant sequence. Using the mutant enzyme as a catalyst and UDPG as a glycosyl donor, the catalytic reaction efficiency for the substrates steviol glycoside ST, rebaudioside A (RebA), and rebaudioside D (RebD) can be significantly improved. The glycosyltransferase UGT76G1 mutant constructed in this study improves its catalytic activity, and the efficient production of rebaudioside M is achieved through optimization of the reaction system.

This invention relates to the field of detection, specifically to a method for the simultaneous determination of four flavoring agents in montmorillonite powder using high-performance liquid chromatography (HPLC). The method detects four flavoring agents in montmorillonite powder: sodium saccharin, aspartame, vanillin, and steviol glycoside. All four flavoring agents are separated from the baseline with satisfactory resolution, and there is no interference from excipients. The limits of detection (LODs) for sodium saccharin, aspartame, vanillin, and steviol glycoside are 4.66, 7.87, 7.81, and 8.51 ng / mL, respectively; the limits of quantitation (LOQs) are 13.98, 26.23, 26.02, and 25.52 ng / mL, respectively. The method developed in this invention exhibits high repeatability and stability, and can be used for the identification and content determination of flavoring agents in montmorillonite powder, providing a reference for the quality control of flavoring agents in montmorillonite powder.

The utility model discloses a preparation device of glucose stevioside, and relates to the technical field of glucose stevioside production, an inlet of a conversion tank is respectively communicated with a raw material tank, an auxiliary material tank and a cyclodextrin glucoside transferase tank, an outlet of the conversion tank is communicated with a hydrolysis tank, an outlet of the hydrolysis tank is communicated with a reaction tank, and the reaction tank is communicated with a reaction tank. The inlet of the reaction tank is respectively communicated with a sucrose tank, a sucrose synthase tank, a uridine diphosphate tank, a first UGT glycosyltransferase tank, a second UGT glycosyltransferase tank and an alkali liquor tank; an outlet of the reaction tank is communicated with a first macroporous adsorption resin column, an inlet of the first macroporous adsorption resin column is communicated with a first ethanol tank, an outlet of the first macroporous adsorption resin column is communicated with a first concentration tank, and a lower outlet of the first concentration tank is communicated with a first dryer; and an outlet of the first dryer is communicated with a first glucosyl stevioside tank. And the residual substrate is converted into stevioside with relatively better taste, so that the taste and quality of the product are improved.

Compositions comprising high purity glycosylated steviosides and / or Maillard reaction products thereofare described. These compositions provide improved taste profiles and can be used as sweeteners or flavorants in consumable products, including foods and beverages.

The invention discloses a method for improving emulsibility and thermal stability of whey protein isolate, and relates to the technical field of protein processing. The preparation method comprises the following specific steps: respectively dissolving whey protein isolate, sodium alginate and steviol glycoside in water, and fully hydrating to obtain a whey protein isolate solution, a sodium alginate solution and a steviol glycoside solution; adjusting the pH values of the three solutions, and mixing according to a certain sequence and proportion to obtain a mixed solution; the obtained mixed solution has good emulsibility and thermal stability, and compared with single WPI, the emulsion stability is increased by 25.2 times. And a practical method is provided for improving the environmental sensitivity and emulsibility of the whey protein isolate.

The present invention relates to novel rebaudioside D and rebaudioside M-like steviol glycosides and a method for producing same. The novel rebaudioside D and rebaudioside M-like steviol glycosides obtained by the production method according to the present invention exhibit improved water solubility, and thus can be easily applied to beverages and foods with a high water content, and can significantly improve the industrial utilization of steviol glycosides.

The utility model discloses a kind of multi-enzyme step-by-step preparation glucosyl steviol glycoside's device, it is related to glucose steviol glycoside production technical field, the inlet of first reaction tank is respectively communicated with raw material tank, dextrin tank, cyclodextrin glucoside transferase tank and first sodium hydroxide solution tank, the outlet of first reaction tank is communicated with hydrolysis tank, the outlet of hydrolysis tank is communicated with second reaction tank, the inlet of second reaction tank is respectively communicated with sucrose tank, sucrose synthase tank, uridine diphosphate tank, UGT glycosyltransferase tank and lye tank, the outlet of second reaction tank is communicated with concentration tank by pipeline, the lower outlet of concentration tank is communicated with drier, the outlet of drier is communicated with glucosyl steviol glycoside tank. Make residual substrate conversion is relatively more optimal steviol glycoside in taste, improve the taste, quality and yield of product.

Disclosed are methods and compositions for glycosylation of a sugar acceptor, comprising the steps of: (i) converting an exogenous nucleoside triphosphate (NTP) to a nucleoside diphosphate (NDP); (ii) converting the NDP to NDP-sugar, comprising contacting at least one Leloir glycosyltransferase (GT) with the NDP and an exogenous sugar donor (SD) in a reaction medium; and (iii) converting a sugar acceptor (SA) to a glycosylated SA, comprising contacting the at least one GT with the NDP-sugar and the SA in the reaction medium.

The present disclosure provides enzymes and methods of using those enzymes to transfer sugar moieties to substrate steviol glycosides. Specifically, designed beta-1,2-glycosyltransferases and sucrose synthases are used in one-pot reactions to convert stevioside and Reb A to Reb E and Reb D. Additionally, designed beta-1,2-glycosyltransferases can be used in one-pot reactions with sucrose synthases and beta-1,3-glycosyltransferases to produce Reb M from stevioside and / or Reb A.

The application discloses a transcription factor SrMYB1 for regulating synthesis of steviol glycoside, an expression protein thereof and application, and belongs to the technical field of plant genetic engineering. The transcription factor SrMYB1 has a nucleotide sequence as shown in SEQ ID NO. 1, and the amino acid sequence of the expression protein is as shown in SEQ ID NO. 2. Subcellular localization in tobacco epidermal cells shows that the protein coded by the gene is mainly located in the nucleus; yeast activity experiment shows that the protein has transcription activation activity. Yeast single hybridization experiment shows that SrMYB1 can be combined on the promoter of a key gene for synthesis of steviol glycoside SrUGT76G1 . Promoter activity and transgenic experiment both show that SrMYB1 significantly inhibits transcription of the key gene for synthesis of steviol glycoside SrUGT76G1 . Based on the characteristics, certain reference can be provided for quality regulation of steviol glycoside and cultivation of new steviol varieties.

Compositions and consumables comprising at least one D-sugar or L-sugar and a non-sucrose sweetener (e.g., a steviol glycoside sweetener or mogroside sweetener) are provided herein. Methods for modulating one or more taste attributes, included enhancing sweetness, improving temporal profile, reducing sweet linger, reducing bitterness, improving mouthfeel, improving taste and / or sweet intensity, of a consumable are disclosed. The compositions and methods can be used to make a consumable taste more like a sucrose-sweetened consumable.