102 results about "N-Acetylneuraminic acid" patented technology

The invention discloses novel N-acetylneuraminic acid-producing escherichia coli engineering bacteria as well as a construction method and application thereof. The engineering bacterial is constructed by introducing an encoded 6-glucosamine phosphate acetylase gene, an N-acetyl glucosamine-2-isomerase gene and an N-acetylneuraminic acid synthetase gene into escherichia coli to express, carrying out strengthened expression on 6-glucosamine phosphate deaminase gene contained in the escherichia coli per se and knocking off genes, for decomposing and utilizing enzyme in metabolic pathways, of the N-acetylneuraminic acid in the engineering bacteria. The engineering bacteria disclosed by the invention can be used for fermentation culture to synthesize the N-acetylneuraminic acid by using glucose or glycerinum as a substrate.

Provided are a method for promoting insulin secretion, a method for suppressing the elevation of a blood glucose level, a method for ameliorating diabetes mellitus, a method for promoting growth of an animal, and a method for increasing an insulin level in breast milk. These methods comprising administering at least one member selected from the group consisting of a di- or a higher saccharide containing galactose, a derivative thereof, a saccharide containing N-acetylneuraminic acid, and a derivative thereof, to a patient in need thereof or an animal.

The invention relates to child formula milk powder beneficial to eye protecting and brain intelligence development helping. The child formula milk powder is prepared from docosahexaenoic acid, arachidonic acid, lutein, N-acetylneuraminic acid, phosphatidylserine (PS), (3R,3'R)-dihydroxy-beta-carotene, phospholipid, vitamins, folic acid, taurine, choline chloride, ferrous sulfate and zinc sulfate.Through three major nutritional systems of an intelligence and vision core nutrition system, a vision BLZ system and an intelligence NPC system, a formula not only provides basic nutrition elements for the development of brains and eyes, but also protects the eyes through the vision BLZ system and reduces loss of the eyes; necessary nutrition is provided for the connection of cerebral nerve cellsthrough the intelligence NPC system.

The invention discloses recombinant corynebacterium glutamicum for accumulating N-acetylneuraminic acid and application thereof and belongs to the field of genetic engineering. The recombinant corynebacterium glutamicum takes corynebacterium glutamicum as an expression host, and an N-acetylneuraminic acid synthesis way is reinforced through over-expression of a glucosamine-fructose-6 phosphate aminotransferase gene, a glucosamine acetylase encoding gene, a phosphatase encoding gene, an acetylglucosamine isomerase encoding agene and an N-acetylneuraminic acid synthase encoding gene; an N-acetylneuraminic acid transport protein encoding gene in the corynebacterium glutamicum and a related gene in an intracellular N-acetylneuraminic acid decomposition, utilization and metabolism are knocked off to obtain corynebacterium glutamicum genetically engineered bacteria for extracellularly accumulating the N-acetylneuraminic acid and the yield reaches 110mg/L; a foundation is laid for further modifying corynebacterium glutamicum through metabolic engineering to produce the N-acetylneuraminic acid.

The invention discloses genetically engineered bacteria for producing N-acetylneuraminic acid as well as a construction method and application thereof. A method for preparing the genetically engineered bacteria for producing N-acetylneuraminic acid comprises the following step of: introducing genes associated with the N-acetylneuraminic acid synthesis into host bacteria so as to obtain recombinant bacteria for producing N-acetylneuraminic acid, wherein the genes associated with the N-acetylneuraminic acid synthesis are coding genes of N-acetylglucosamine and 2-isomerase and a coding gene of N-nacetylneuraminic acid aldolase. The genetically engineered bacteria for producing N-acetylneuraminic acid constructed by the invention have the following advantages that the used raw materials are relatively cheap and liable to realize industrial mass product, so that the genetically engineered bacteria play an important role in the production of N-acetylneuraminic acid in the future.

The invention provides a method for producing poly-N-acetylneuraminic acid by fermentation of escherichia coli CGMCC NO.5585 and a purification method of the poly-N-acetylneuraminic acid. The high-purity poly-N-acetylneuraminic acid without endotoxins is further obtained and can meet the production requirements of foods, cosmetics and medicaments. According to the methods provided by the invention, the fermentation raw material uses cheap glucose to replace more expensive sorbitol, the yield of 5-6g/L can be still obtained during the fermentation stage, and the methods are particularly suitable for industrial fermentation production of PSA (polysialic acid); and finally, through the follow-up purification step, the high-purity PSA with the polymerization degree of at least above 70000Da, the purity of at least more than 95% (HPLC(high performance liquid chromatography)) and the yield of 4-4.5g/L can be obtained.

The present invention discloses a process of producing N-acetylneuraminic acid with two kinds of immobilized enzyme. In the process, immobilized N-acetylglucosamine-2-epimerase (E.C.5.1.3.8) in the concentration of 0.6-10 U/ml and immobilized N-acetylneuraminate aldolase (E.C.4.1.3.3) in the concentration of1.2-10 U/ml are utilized in the identical reactor to convert N-acetylglucosamine and pyruvic acid or its salt into N-acetylneuraminic acid. The process can reach N-acetylglucosamine converting rate up to 77 %, and has a conversion reaction period within 20 hr, repeated use of enzyme source and great industrial significance.

The invention discloses a high-yield N-acetylneuraminic acid metabolic engineering bacterium and a construction method and application. According to the engineering bacterium, the activity of coded UDP-N-acetylglucosamine epimerase and N-acetylneuraminic acid synthetase gene enzyme is enhanced by expressing the two enzymes in Escherichia coli through a T7 strong promoter, and the recombinant Escherichia coli is constructed by removing genes of an N-acetylneuraminic acid decomposition pathway enzyme in the Escherichia coli; and a constructed engineered strain utilizes glucose or glycerinum as a substrate for fermentation cultivation to generate N-acetylneuraminic acid. The engineering bacterium utilizes glucose or glycerinum for synthesizing the N-acetylneuraminic acid, so that the fermentation level is high, the accumulated by-products are few, and the engineering bacterium has the industrial potential.

The invention discloses recombinant escherichia coli of a temperature-control coexpression exogenous gene, which is named as Escherichia coli DT26 (pBVNsS) CCTCC NO:M 209018. The genotype of the recombinant escherichia coli is delta nagE::FRT; and the recombinant escherichia coli contain a temperature-control coexpression carrier pBVNsS. Simultaneously, the invention also discloses the application of the recombinant escherichia coli used as a catalyst for the complete cell catalytic preparation of N-acetylneuraminic acid. In the process of the large-scale catalytic production of the N-acetylneuraminic acid, the recombinant escherichia coli of the temperature-control coexpression exogenous gene has the characteristics of safe and convenient preparation of the catalyst, simple operation of the catalytic process, cheap price, higher efficiency, easy extraction and the like.

The invention provides infant formula milk powder rich in milk fat globule membrane protein and phospholipid. By adding alpha-lactalbumin, milk fat globule membrane and a physiological activator, suchas bifidobacterium animalis Bb-12, milk fat globule membrane lipids and protein, N-acetylneuraminic acid (sialic acid), SN-2 structure lipid, human milk oligosaccharides (HMOs) and human milk oligose(HMO). By simultaneously adjusting the using amount ratio of all the components, especially sphingomyelin, gangliosides, the milk fat globule membrane protein, the human milk oligosaccharides, the human milk oligose, adiponectin and lysozyme, and the proportion between mucin, xanthine oxidoreductase, mucin 15, CD 36, butyrophilin, adipose differentiation-related protein and fatty acid binding proteins, the content of the active ingredients in the milk powder is closer to the content of active ingredients in human milk, the constitution of the infant formula milk powder is optimized, and the formula milk powder obtained by using the method is closer to the human milk.

The invention discloses a method for preparing high-purity N-acetylneuraminic acid hydrate by a supersaturation crystallization process. The N-acetylneuraminic acid hydrate is prepared through low-temperature standing crystallization of a supersaturated aqueous solution of N-acetylneuraminic acid. A result of detection after drying of the N-acetylneuraminic acid hydrate shows that the purity is 99% or more, so requirements in the fields of foods, health care and medicines are met; and the method is simple, is easy to operate, and is especially suitable for industrial fermentation production ofthe N-acetylneuraminic acid hydrate.

The present invention relates to a lectin protein, designated MFA isolated and purified from the bark of the Korean legume Maackia fauriei, process for preparing the same and the use thereof. This protein can be used as reagents in the study of carbohydrate binding proteins as well as to examine the distribution of N-acetylneuraminic acid in cancer cells owing to its capability that specifically recognizes N-acetylneuraminic acid which plays important structural and functional roles in the expressions of various cells or oligosaccharide terminal residue of glycoconjugates, and, in addition, used as an anti-cancer drug in view of its anti-proliferation effect against various cancers such as breast cancer, melanoma, hepatoma, etc.

A chemiluminescent system for detecting the presence of influenza virus in a biological fluid sample is provided. An influenza diagnostic kit is provided which includes (1) a sampling device for obtaining the biological fluid from a subject, (2) a chemiluminescent substrate material which, in the presence of influenza virus in the biological sample, will generate a chemiluminescent product that will produce detectable light, and (3) a means for detecting any generated light. A liquid sample containing the biological fluid, and preferably a diluent, are contacted with the an absorbent material containing the chemiluminescent substrate material. The substrate responds to neuraminidase activity intrinsic to influenza A and influenza B virus particles, such that when the substrate is in contact with influenza virus, the substrate is cleaved to yield a chemiluminescent product that then decomposes to produce light which can then be detected. The chemiluminescent substrate materials include enzymatically triggerable 1,2-dioxetane derivatives of 4-alkoxy-N-acetylneuraminic acid and 4,7-dialkoxy-N-acetyineuraminic acid. The system is sufficiently simple that it can reliably be used by a layperson in a nonmedical setting. The biological fluid generally originates from the oral cavity, the pharyngeal cavity, or the nasopharyngeal cavity.

The invention discloses recombinant bacteria for high-yield production of N-acetylneuraminic acid by utilizing manual double carbon sources and belongs to the field of genetic engineering. A gluconicacid kinase gene gntK and gluconic acid permease gntP are overexpressed through a strong promoter P43, and the manual double carbon sources including glucose and sodium gluconate are used for fermenting to realize efficient supply of phosphoenolpyruvic acid in an N-acetylneuraminic acid synthesis way and the synthesis way is strengthened. Compared with a starting strain, recombinant bacillus subtilis has the advantage that the yield of N-acetylneuraminic acid is improved to 1.52g/L from 1.02g/L; a foundation is laid for producing N-acetylneuraminic acid by carrying out further metabolic engineering modification on the recombinant bacillus subtilis.

The invention discloses a whey protein solid beverage containing N-acetylneuraminic acid. The beverage is prepared from sugar, concentrated whey protein powder, whole milk powder, N-acetylneuraminic acid, probiotics, prebiotics, ethylenediaminetetraacetic acid ferric sodium salt and casein phosphopeptides. According to the whey protein solid beverage, all raw materials are effectively combined, the immunity of all kinds of people including infants and young children can be effectively enhanced, the whey protein content is high, nutrition is rich, absorption is facilitated, and more sufficientnutrition and energy can be provided for drinkers.