79 results about "Tetrasaccharide" patented technology

The invention relates to the technical field of biology, in particular to a beta-1, 4-galactosyl transferase mutant and a method for biologically synthesizing lactose-N-neotetraose by using the beta-1, 4-galactosyl transferase mutant. The invention discloses a protein, which is a protein HpgalT-186 or a protein HpgalT-146-186, a protein HpgalT-146 and a protein HpgalT-146. The protein HpgalT-186 is a protein obtained by mutating an amino acid residue at the 186th site of a wild type HpgalT; the protein HpgalT-146-186 is a protein obtained by carrying out mutation on an amino acid residue at the 186 site and an amino acid residue at the 146 site of wild type HpgalT. On the basis, a series of escherichia coli is constructed and optimized, the yield of the LNnT synthesized through shake flask fermentation of the finally obtained strain reaches 1.73-4.1 g / L, the highest yield in a 5L fermentation tank reaches 20-45.2 g / L, and efficient synthesis of the LNnT is achieved.

The invention discloses a molecular modification design method for improving the catalytic activity and the thermal stability of citrobacter vinegaticus-derived hyaluronidase and expression application of the citrobacter vinegaticus-derived hyaluronidase. The interaction of citrobacter vinegaticus hyaluronidase active pocket amino acid residues and hyaluronate tetrasaccharide molecules is visually explored through Pymol, conservative analysis of pocket amino acid evolution is carried out through Consurf, and rational design is carried out through policies of FoldX for calculating enzyme-substrate binding free energy, so that the hyaluronidase catalytic activity is improved. A mutant with significantly improved enzyme activity is obtained through screening, and the thermal stability of the enzyme is further improved through PROSS design and an analysis strategy of mutation site amino acid evolution conservative property and position. According to the invention, the sequence, structure and function of hyaluronidase are deeply studied, and hyaluronidase is mutated from two aspects of stabilizing a catalytic structure and promoting a catalytic reaction, so that a high-activity enzyme with higher application value in industrial production is obtained.

The invention discloses a preparation method of chitosan oligosaccharide. The method comprises the following steps: adding chitin into concentrated hydrochloric acid, grinding until the chitin is dissolved into paste, washing with distilled water, and collecting to obtain a white colloidal substance, namely colloidal chitin; dissolving colloidal chitin in a phosphoric acid-citric acid buffer solution to obtain a mixed dissolved solution; adding a crude enzyme solution of composite chitinase into the mixed dissolving solution, placing the mixed dissolving solution in a shaking table for reaction, terminating the reaction in a boiling water bath, centrifuging, and carrying out activated carbon separation, low-temperature rotary evaporation concentration and freeze drying on supernate to obtain a chitosan oligosaccharide finished product. According to the method, chitinase crude enzyme liquid prepared from bacillus subtilis SH21 and chitinase crude enzyme liquid prepared from penicillium oxalicum K10 are used as compound enzymes, chitin is subjected to enzymolysis to prepare the chitosan oligosaccharide, the polymerization degree of the prepared chitosan oligosaccharide is 3-10, trisaccharide, tetrasaccharide, pentasaccharide and hexasaccharide are mainly used, and compared with single enzyme use, the compound enzymes are high in product yield and high in chitin degradation rate.

The present disclosure relates to a composition for balancing the immune system of a neonatal or infant subject, the composition comprising an effective amount of 2 '-fucosyllactose, 3-fucosyllactose, 3'-sialyllactose, 6 '-sialyllactose, and lactose-N-tetrasaccharide.

The preparation method comprises the following steps: (1) dissolving agar in a citric acid monohydrate solution, and carrying out acidolysis to obtain an acidolysis solution; centrifuging, filtering, adding beta-agarase AgWH50B, and carrying out enzymolysis for 20-28 hours at the temperature of 30-35 DEG C; boiling, centrifuging and filtering to obtain supernate, namely crude oligosaccharide liquid containing agarotriose; (2) dissolving agar in a phosphoric acid solution, and degrading for 55-65 minutes at the temperature of 97-103 DEG C; centrifuging and filtering to obtain supernate, namely crude oligosaccharide liquid containing agarobiose; (3) dissolving agar in deionized water, adding alpha-agarase A33, and carrying out enzymolysis at 38-42 DEG C for 20-28 hours; and boiling, centrifuging and filtering to obtain supernate, namely crude oligosaccharide liquid containing agarotetraose. The preparation method of the agaro-oligosaccharide is used for preparing agarotriose, agarobiose and agarotetraose, and the product purity is high. The method can provide guidance for subsequent large-scale industrial production of agaro-oligosaccharide.

The invention belongs to the technical field of microorganisms, and particularly relates to bacillus sp. SQ8, a method for producing dextranase by using the bacillus sp. SQ8 and application of the bacillus sp. SQ8. The strain is strong in growth adaptability and high in enzyme production efficiency. The dextranase produced by the strain SQ8 can be used for preparing high-polymerization-degree isomaltooligosaccharides, in hydrolysate of the strain SQ8, the ratio of tetrasaccharide is 10.8%, the ratio of pentasaccharide is 19.7%, the ratio of hexasaccharide is 42.1%, the ratio of heptasaccharide is 22.7%, the ratio of high-polymerization-degree isomaltooligosaccharides is 95.3%, and the dextranase produced by the strain SQ8 can be used for preparing high-polymerization-degree isomaltooligosaccharides and has a good application prospect.

The invention discloses a beta 1, 3-galactosyl transferase Pm beta 3GalT-S207H and an application thereof, and belongs to the technical field of functional enzymes. And the amino acid sequence of the beta 1, 3-galactosyl transferase Pm beta 3GalT-S207H is as shown in SEQ ID NO. 3. The invention further discloses the application of the beta 1, 3-galactosyl transferase Pm beta 3GalT-S207H in the preparation of lactose-N-tetrasaccharide. According to the invention, 1, 3-galactosyl transferase Pm beta 3GalT is subjected to mutation modification to obtain a mutant enzyme, and compared with a wild enzyme, the enzyme activity of the mutant enzyme is improved by 157.21% and is obviously improved, and the thermal stability and alkali resistance are also obviously improved. The beta 1, 3-galactosyl transferase Pm beta 3GalT-S207H disclosed by the invention has important theoretical value and application value on the industrial production of LNT (Lipoxystrobin).

The invention belongs to the field of food, particularly relates to a nutritional composition and application thereof in improving immune disorder, and more particularly relates to application of the nutritional composition in preparing food for improving filial generation body inflammatory factor level disorder caused by maternal immune activation. The nutritional composition comprises essential active ingredients shown as the following (i) and (ii): (i) a neutral fucosylated breast milk oligosaccharide, (ii) a neutral non-fucosylated breast milk oligosaccharide; wherein the neutral fucosylated breast milk oligosaccharide at least comprises 2 '-fucosylated lactose, and the neutral non-fucosylated breast milk oligosaccharide at least comprises lactose-N-neotetraose; in addition, in the nutritional composition, the mass ratio of the lactose-N-neotetraose to the 2 '-fucosyllactose is 1: (1-8), and the 2'-fucosyllactose and the lactose-N-neotetraose can achieve a synergistic effect to regulate filial generation immunity.

This invention discloses a high-yield lactyl-3-4 ...5-4-4-4-4-4- N This invention relates to plasmid-free genetically engineered strains of tetrasaccharides and their applications, belonging to the field of microbial genetic engineering. The invention screened strains with higher activity. β -1,3-galactosyltransferase gene PmgalT Computer-aided enzyme function modification was used to achieve a shake-flask yield of 10.05 g / L for the constructed mutant. Subsequently, genome integration was performed... breast Multi-copy integration PmgalT * V27I / V39I / Y147F ‑galE‑galU A plasmid-free strain was constructed, enabling it to grow in shake flasks with lactoyl- N The yield of tetrasaccharides reached 14.4 g / L. Using glucose as the sole carbon source, the highest yield of 68.19 g / L was achieved at 64.5 h; using glycerol as the sole carbon source, the highest yield of 62.88 g / L was achieved at 60.5 h, providing a basis for its industrial production.

The invention belongs to the technical field of biological medicine, and particularly relates to a mycoplasma synoviae culture medium capable of improving strain titer and a preparation method of the mycoplasma synoviae culture medium. The mycoplasma synoviae culture medium comprises a basic culture medium and auxiliary components, the basic culture medium is prepared from HEPES, milk protein hydrolysate, MEM, beef heart extract powder, coenzyme I, 1% phenol red, magnesium sulfate heptahydrate, L-cysteine hydrochloride, lactose-N-tetrasaccharide, disodium clodronate and water; the auxiliary components comprise porcine serum and penicillin. According to the mycoplasma synoviae culture medium obtained by the preparation method, the passage time of the mycoplasma synoviae is shortened, and the strain titer is improved. The inactivated vaccine prepared from the chicken mycoplasma synoviae cultured by the culture medium is good in safety and immunogenicity, can effectively prevent infection of the chicken mycoplasma synoviae, and has a good application prospect.

The present application relates to the technical field of human milk oligosaccharide production, and in particular to a production method of high-purity lacto-N-neotetraose crystal. The production method inoculates the E. coli BL21 star (DE3) BLBRTXST3 strain into a seed liquid culture medium to obtain a seed liquid, then accesses a fermenter in a certain proportion, accurately adjusts the temperature, pH and dissolved oxygen, and adds a final concentration of 0.1 mM IPTG for induction during the product synthesis period, supplements glycerol and lactose in an exponential flow addition mode, inhibits the generation of the by-product lacto-N-neohexaose, significantly improves the yield and purity of lacto-N-neotetraose, and finally obtains a lacto-N-neotetraose crystal product with a purity of ≥98% by combining the optimized crystallization process. The method has the advantages of high yield, high purity, few by-products, controllable process safety, and strong industrialization adaptability.

The invention relates to a beta-carrageenan enzyme mutant AfCarY123A and application thereof, and belongs to the technical field of functional enzymes, and the amino acid sequence of the mutant AfCarY123A is as shown in SEQ ID NO. 1. The invention further provides an enzyme preparation containing the mutant AfCarY123A, a recombinant expression vector containing a gene for coding the mutant AfCarY123A, a recombinant engineering bacterium and application of the recombinant expression vector and the recombinant engineering bacterium. The mutants can be used for degrading kappa-carrageenan into kappa-neocarrageenan tetrasaccharide, kappa-neocarrageenan hexasaccharide, kappa-neocarrageenan octasaccharide, kappa-neocarrageenan decasaccharide and kappa-neocarrageenan dodecasaccharide.

The invention relates to the technical field of cosmetics, in particular to acer truncatum moisturizing pre-makeup cream and a preparation method thereof. The acer truncatum moisturizing makeup pre-cream is prepared from the following components in parts by weight: acer truncatum seed oil, cosmetic-grade purified water, cetyl PEG / PPG-10 / 1 polydimethylsiloxane, polydimethylsiloxane, isononyl isononanoate, synthetic wax, microcrystalline wax, glycerol, 1, 2, 4-trimethyl-1, 3-pentanediol monoisobutyrate, propylene glycol monobutyl ether, propylene glycol monobutyl ether, propylene glycol monobutyl ether, propylene glycol monobutyl ether, propylene glycol monobutyl ether, propylene glycol the mannuronic acid tetrasaccharide micro-capsule is coated with 1, 3-propylene glycol / caprylyl glycol / ethylhexylglycerin, butanediol, sodium chloride, a sodium hyaluronate cross-linked polymer and temperature-sensitive polyglycerol-10 stearate. The acer truncatum seed oil containing 6% of nervonic acid serves as core lipid, temperature-sensitive type microencapsulated mannuronic acid tetrasaccharide and response type composite microcapsules are compounded, a'instant moisturizing-delayed moisturizing-barrier repairing 'triple synergistic system is constructed, the defects of a traditional technology are overcome, and the requirements of consumers for long-acting, efficient and mild pre-makeup care are met.

The present invention provides protected tetrasaccharides, their process of preparation and their use as common scaffold precursors in the synthesis of oligosaccharides representing segments of the O-antigens from diverse S. flexneri serotypes, comprising for example SF2a, SF3a, SF2b, SF1b, SFX and / or SFY.

The invention belongs to the technical field of synthesis of polysaccharide conjugate vaccines, and relates to a proteus mirabilis O3a O-antigen tetrasaccharide repeating unit containing an adamantane skeleton, an antigen and a polysaccharide conjugate vaccine. The active ingredients of the polysaccharide conjugate vaccine provided by the invention comprise a subject and an object, and the subject and the object are mutually combined through non-covalent interaction; the subject comprises a compound of beta-cyclodextrin and carrier protein, and the guest comprises maltotriose containing an adamantane skeleton or a proteus mirabilis O3a O-antigen containing an adamantane skeleton. The proteus mirabilis O3a O-antigen tetrasaccharide repeating unit containing the adamantane skeleton is successfully synthesized with high stereoselectivity and excellent yield by adopting a [2 + 1 + 1] graded assembly strategy, and the research can lay a firmer theoretical and practical foundation for research and development of proteus mirabilis resistant vaccines.

The application provides a genetically engineered bacterium for producing lactose-N-neotetraose, a construction method and application thereof. The genetically engineered bacterium satisfies the following conditions: (1) exogenous expression of MFS transporter protein, beta-1, 3-N-acetylglucosamine transferase and beta-1, 4-galactosyltransferase; (2) overexpression of galactoside permease and UDP-galactose-4-epimerase; and (3) no expression or weakened expression of setA transporter protein. The applicant of the application finds through research that exogenous introduction of MFS transporter protein, beta-1, 3-N-acetylglucosamine transferase and beta-1, 4-galactosyltransferase in the genetically engineered bacterium, enhancement of the expression amount of galactoside permease and UDP-galactose-4-epimerase in the genome, and reduction of the expression amount of setA transporter protein can effectively reduce the residual amount of LNT II in the LNnT synthesis pathway and improve the fermentation yield of LNnT.

The invention discloses application of a nutritional composition containing breast milk oligosaccharide to improvement of repeated engraving behaviors, and belongs to the field of nutrient substance research. The present invention provides a composition comprising lactose-N-neotetraose and 2 '-fucosyllactose, both of which have a synergistic effect and can improve a repeated engraving behavior, which is caused by maternal immune abnormal activation. Furthermore, the composition can inhibit the transition activation of brain microglial cells and improve the activity of neurons, so that the brain neural network damage is improved, and help is provided for improving repeated engraving behaviors. And a new thought is provided for the development of products for improving repeated engraving behaviors caused by maternal immune activation.

The invention relates to a hydrogel product comprising glycosaminoglycan molecules as the swellable polymer, wherein the glycosaminoglycan molecules are covalently crosslinked via crosslinks comprising a spacer group selected from the group consisting of di-, tri-, tetra-, and oligosaccharides.

The application belongs to the technical field of genetic engineering, and discloses a kind of synthetic lactosyl-N-neotetraose and safe recombinant bacillus subtilis and its construction method and application, the recombinant bacillus subtilis is obtained by transforming plasmid containing beta-1,3-N-acetylglucosamine transferase, beta-1,4-galactosyltransferase gene and lactose permease gene in bacillus subtilis 168.The application aims at the huge demand of lactosyl-N-neotetraose in the market in prior art, and the lactosyl-N-neotetraose produced by most existing engineering bacteria is not safe, provides an engineering bacteria for producing lactosyl-N-neotetraose and application, to meet the demand of lactosyl-N-tetraose in the market.

The invention provides breast milk oligosaccharide capable of improving bioavailability of mineral zinc and application of the breast milk oligosaccharide. Specifically, the invention provides an application of lactose-N-neotetraose (LNnT) in preparation of a product for improving the bioavailability of mineral zinc. The bioavailability of mineral zinc can be improved by utilizing the lactose-N-neotetraose, especially for zinc-deficient individuals, the retention rate of the zinc in the individuals can be remarkably improved, and digestion and absorption of the individuals to the zinc are promoted.

The invention discloses a preparation method of low-viscosity polydextrose, and belongs to the technical field of polydextrose preparation. Carrying out multi-stage polymerization reaction on the saccharified liquid, and then refining to obtain low-viscosity polydextrose; the saccharification liquid comprises 10 wt% of glucose, 40 wt% of maltose, 40 wt% of maltotriose, and 10 wt% of tetrasaccharide or above; the multi-stage polymerization reaction specifically comprises the following steps: adding 1wt% of citric acid and 1wt% of sorbitol into the saccharified liquid, and reacting under a high-temperature condition until the content of glucose is 1t; 2 wt%; glucose is supplemented, the adding amount is 10-30 wt% of that of the previous system, and the reaction continues until the glucose content is 1t; 2 wt%; supplementing 20-40wt% of glucose, and continuing the reaction until the content of the glucose is 1t; and 2 wt%. Starch can be adopted as a raw material, and pigment accumulation is reduced by adopting a specific preparation method; meanwhile, the viscosity of the polydextrose is reduced by controlling the size of a molecular chain.

The invention provides a preparation method of an antibody conjugate containing an sLeX tetrasaccharide structure, which comprises the following steps: S1, sequentially adding Endo S2 enzyme and alpha-L-fucosidase into a target antibody, and respectively analyzing glycosylation to avoid modification site conflict or carbohydrate chain structure interference; s2, adding the accurately represented antibody in the S1, B4GalT1 and UDP-Gal into a Tris-HCl system containing Mn < 2 + >, and incubating to obtain a reaction solution I; s3, the reaction liquid I, ST3Gal3, CMP-Neu5Ac and Tris-HCl containing Mg < 2 + > are taken and mixed, and incubation is carried out; adding CMP-N-acyl neuraminic acid phosphodiesterase for reaction, and purifying Protein A to obtain a purified antibody I; s4, the purified antibody I, alpha1, 3 FucT-2HR, GDP-Fuc and Tris-HCl containing Mg < 2 + > are taken and mixed, and incubation is performed; and purifying Protein A to obtain a target product. According to the modified antibody obtained by the invention, while the targeting property is improved, the binding affinity of the antibody and a tumor cell surface antigen can be enhanced, so that the immune blocking activity of the antibody is further enhanced, and dual improvement of the targeting property and the activity is realized.

The invention belongs to the field of food, and particularly relates to a nutritional composition and application thereof in improving sleep. The invention provides a nutritional composition. The nutritional composition comprises necessary active ingredients shown as (I) and (II) as follows: (I) casein phosphopeptides and (II) neutral non-fucosylated breast milk oligosaccharides, wherein the casein phosphopeptides are casein phosphopeptides, the casein phosphopeptides are casein phosphopeptides, the casein phosphopeptides are casein phosphopeptides, the neutral non-fucosylated breast milk oligosaccharide at least contains lactose-N-neotetraose, and in the nutritional composition, the mass ratio of the casein phosphopeptides to the lactose-N-neotetraose is 1: (0.1-15.0). According to the invention, the combination of the casein phosphopeptides and the lactose-N-neotetraose can effectively improve the sleep problem, even can improve the anxiety state caused by the sleep problem, and the casein phosphopeptides and the lactose-N-neotetraose also have a synergistic interaction effect.

The application provides a hybridoma cell strain secreting a monoclonal antibody against a alginate mannuronic acid tetrasaccharide epitope, a monoclonal antibody and application. In order to enhance the immunogenicity of the mannuronic acid tetrasaccharide, a glycoconjugate KLH-1 is used as an immunogen to inject and immunize a mouse, so that the mouse is stimulated to produce a specific immune response against the mannuronic acid tetrasaccharide epitope, then spleen cells of the immunized mouse are fused with myeloma cells, and after screening, an initial hybridoma cell strain is obtained; then after subcloning and specific screening, a hybridoma cell strain capable of stably secreting a monoclonal antibody of the target mannuronic acid tetrasaccharide epitope in alginate is obtained, and a monoclonal ascites antibody is further obtained. The monoclonal ascites antibody shows specific recognition and combination ability for pseudomonas aeruginosa, and the combination activity is related to the expression level of alginate on the surface of the bacteria. Therefore, the monoclonal ascites antibody can be used as a precise detection and diagnosis tool for pseudomonas aeruginosa, and can also be applied to the antibacterial treatment of pseudomonas aeruginosa infection.

The application relates to a stone moss polysaccharide cleavage enzyme JpPL40A and application thereof, and belongs to the technical field of functional enzymes. The amino acid sequence of the stone moss polysaccharide cleavage enzyme JpPL40A is shown as SEQ ID NO. 1, and the coding gene is shown as SEQ ID NO. 2 or SEQ ID NO. 3. The stone moss polysaccharide cleavage enzyme JpPL40A can hydrolyze stone moss to obtain unsaturated stone moss disaccharide, tetrasaccharide, hexose and / or octose.

The invention relates to the technical field of genetic engineering, in particular to recombinant escherichia coli capable of increasing the yield of lactose-N-tetraose and construction and application of the recombinant escherichia coli. According to the invention, a technology of AI intelligent auxiliary regulation and control of metabolic flux is utilized, and specific gene modification is carried out on escherichia coli in combination with optimization of a metabolic pathway, so that the synthesis efficiency and yield of lactose-N-tetrasaccharide (LNT) produced by recombinant escherichia coli are remarkably improved, and raw material consumption and byproduct generation are reduced, so that the production cost is effectively reduced. By combining the AI technology, strain development and process optimization can be accelerated, and the development period is shortened. According to the invention, through genetic engineering modification and optimization of process conditions, efficient industrial production of LNT is realized, and the growth demand of the market is met.

The present invention provides a fucosylated human milk oligosaccharide (HMO) for use in improving brain development and / or vision development in a subject wherein: a) the fucosylated HMO is lactose-N-fucopentasaccharide-I (LNFP-I) and the subject is an infant of up to 12 months of age; and / or b) the fucosylated HMO is A-tetrasaccharide, wherein the individual is an infant, toddler or child.

The present application relates to the technical field of genetic engineering, and particularly relates to a recombinant escherichia coli for improving the yield of lactose-N-tetrasaccharide, construction and application thereof. The present application uses the technology of AI intelligent auxiliary regulation of metabolic flow, combines with optimization of metabolic pathways, and performs specific genetic modification on escherichia coli, so as to significantly improve the synthesis efficiency and yield of recombinant escherichia coli for producing lactose-N-tetrasaccharide (LNT), reduce raw material consumption and byproduct generation, and thus effectively reduce the production cost. The present application can accelerate the development of strains and process optimization, and shorten the development cycle in combination with AI technology. The present application realizes the efficient industrial production of LNT through genetic engineering modification and optimization of process conditions, and meets the growing demand of the market.

The present application belongs to the field of food, and particularly relates to a nutritional composition and its use for improving sleep. The present application provides a nutritional composition comprising essential active ingredients as shown in (I) and (II) below: (I) casein phosphopeptide, (II) neutral non-fucosylated human milk oligosaccharide; wherein the neutral non-fucosylated human milk oligosaccharide at least comprises lacto-N-neotetraose, and in the nutritional composition, the mass ratio of the casein phosphopeptide to the lacto-N-neotetraose is 1:(0.1-15.0). The present application proposes that the combination of casein phosphopeptide and lacto-N-neotetraose can effectively improve sleep problems, and even can improve the anxiety state caused by these sleep problems, and the two have a synergistic effect.