588 results about "Enzyme catalyzed" patented technology

The invention is directed to enhanced methods for detecting an analyte of interest in situ, by immunoassay, or by hybridization comprising binding an enzyme-labeled conjugate molecule to an analyte of interest in the presence of a redox-inactive reductive species and a soluble metal ion. The enzyme catalyzes the conversion of the inactive reductive species to an active reducing agent, which in turn reduces the metal ion to a metal atom thereby providing an enhanced means of detecting the analyte via metal deposition.

The present invention relates to improved methods of detecting a target using a labeled substrate or substrate analog. The methods comprise reacting the substrate or substrate analog in an enzyme-catalyzed reaction which produces a labeled moiety with independently detectable signal only when such substrate or substrate analog reacts. The present invention, in particular, describes methods of detecting a nucleic acid in a sample, based on the use of terminal-phosphate-labeled nucleotides as substrates for nucleic acid polymerases. The methods provided by this invention utilize a nucleoside polyphosphate, dideoxynucleoside polyphosphate, or deoxynucleoside polyphosphate analogue which has a colorimetric dye, chemiluminescent, or fluorescent moiety, a mass tag or an electrochemical tag attached to the terminal-phosphate. When a nucleic acid polymerase uses this analogue as a substrate, an enzyme-activatable label would be present on the inorganic polyphosphate by-product of phosphoryl transfer. Cleavage of the polyphosphate product of phosphoryl transfer via phosphatase leads to a detectable change in the label attached thereon. When the polymerase assay is performed in the presence of a phosphatase, there is provided a convenient method for real-time monitoring of DNA or RNA synthesis and detection of a target nucleic acid.

A sensor system that detects a current representative of a compound in a liquid mixture features a multi or three electrode strip adapted for releasable attachment to signal readout circuitry. The strip comprises an elongated support which is preferably flat adapted for releasable attachment to the readout circuitry; a first conductor and a second and a third conductor each extend along the support and comprise means for connection to the circuitry. The circuit is formed with single-walled or multi walled nanotubes conductive traces and may be formed from multiple layers or dispersions containing, carbon nanotubes, carbon nanotubes/antimony tin oxide, carbon nanotubes/platinum, or carbon nanotubes/silver or carbon nanotubes/silver-cloride. An active electrode formed from a separate conductive carbon nanotubes layer or suitable dispersion, positioned to contact the liquid mixture and the first conductor, comprises a deposit of an enzyme capable of catalyzing a reaction involving the compound and preferably an electron mediator, capable of transferring electrons between the enzyme-catalyzed reaction and the first conductor. A reference electrode also formed from a conductive carbon nanotube layer or suitable dispersion is positioned to contact the mixture and the second conductor. The system includes circuitry adapted to provide an electrical signal representative of the current which is formed from printing conductive inks made with nano size particles such as conductive carbon or carbon/platinum or carbon/silver, or carbon nanotubes/antimony tin oxide to form a conductive carbon nanotube layers. The multiple-electrode strip is manufactured, by then applying the enzyme and preferably the mediator onto the electrode. Alternatively the electrode can have a carbon nanotubes/antimony tin oxide, carbon nanotubes/platinum, or carbon nanotubes/silver or carbon nanotubes/silver-cloride surface and or a conductive carbon or silver ink surface connecting leg. The carbon nanotube solution is first coated and patterned into electro shapes and the conductive carbon nanotubes, carbon or silver ink can be attached by printing the ink to interface with the carbon nanotube electro surface. A platinum electrode test strip is also disclosed that is formed from either nano platinum distributed in the carbon nanotube layer or by application or incorporation of platinum to the carbon nanotube conductive ink.

The present invention relates to a cell into which an RNA capable of suppressing the function of an enzyme catalyzing a reaction which converts GDP-mannose into GDP-4-keto,6-deoxy-GDP-mannose is introduced; a process for producing a glycoprotein using the cell; a cell into which an RNA capable of suppressing the function of an enzyme relating to modification of a sugar chain in which 1-position of fucose is bound to 6-position of N-acetylglucosamine in the reducing end through α-bond in the complex type N-glycoside-linked sugar chain, and an RNA capable of suppressing the function of an enzyme relating to synthesis of an intracellular sugar nucleotide, GDP-fucose, or an RNA capable of suppressing the function of a protein relating to transport of an intracellular sugar nucleotide, GDP-fucose, to the Golgi body are introduced; a process for producing a glycoprotein composition using the cell; and the like.

A process is disclosed for gas separation wherein carbon dioxide in a mixed gas stream is converted to bicarbonate by contacting a gamma carbonic anhydrase enzyme designated as CAM in the temperature range of 40 degrees to 85 degrees C. in an enzyme catalyzed carbon dioxide capture system.

The present invention is directed to homogeneous phase enzyme-catalyzed processes for producing modified chitosan polymers or oligomers. An enzyme is reacted with a phenolic substrate in the presence of a chitosan polymer or oligomer to produce a modified chitosan polymer or oligomer. The invention also includes modified chitosan polymers or oligomers produced by the novel processes, in particular modified chitosan polymers or oligomers having useful functional properties, such as base solubility and/or high viscosity.

The invention relates to a genetically engineered bacterium producing tetrahydropyrimidine and a structuring method and application thereof. The genetically engineered bacterium is Escherichia coli with a specific genotype, comprises Halomonas-elogata-derived ectABC gene, has three gene deficiency variants including lysA, thrA and iclR and has corynebacterium glutamicum lysC gene controlled by a lac promoter and ppc gene controlled by a trc promoter. The defect that chemical synthesis methods have harsh reaction conditions and high energy consumption can be overcome by using the genetically engineered bacterium and utilizing glucose fermentation to produce tetrahydropyrimidine. The defect that Halomonas-elogata fermentation or enzyme-catalyzed methods are complex in process and high in production cost can be overcome. After fermentation for 20-28h, yield of tetrahydropyrimidine reaches 12-18g/L, and the genetically engineered bacterium has high industrial application value.

Oligosaccharides produced by an alternansucrase enzyme catalyzed reaction of sucrose with an acceptor oligosaccharide are effective as prebiotics for controlling enteric bacterial pathogens. Populations of enteropathogenic bacteria may be substantially reduced or inhibited by treatment of an animal with a composition comprising one or more of these oligosaccharides in an amount effective to promote the growth of beneficial bacteria. The method is particularly effective for the control of Salmonella species, enteropathogenic Escherichia coli, and Clostridia perfringens.

The invention discloses a composite membrane modified biosensor and preparation and application thereof. The biosensor comprises a matrix electrode, the induction end of the matrix electrode is wrapped with an aromatic diamine polymer membrane, a carbon nano tube-Congo red combination layer is modified on the membrane, and a nano gold particle layer is adsorbed on the combination layer. The preparation method comprises the following steps of: forming the polymer membrane at the induction end of the matrix electrode by electric polymerization reaction; and modifying the carbon nano tube-Congo red combination layer on the membrane, and finally electrically depositing nano gold on the combination layer. The biosensor can be applied in detecting target genes; and during detecting, a probe is first designed, then a capture probe is modified, and whether the target genes are contained in hybridization solution to be detected and the concentration of the target genes can be judged by first and second hybridization and enzyme catalytic reaction. The biosensor has the advantages of good electric conductivity, good biocompatibility, high sensitivity, storing anti-interference performance, good selectivity, low manufacturing cost and the like.

The invention provides a preparation method and application of modified starch catalyzed by compound bio-enzymes. The modified starch is a non-toxic environment-friendly new material prepared by modifying raw plant starch by starch modifying assistants and compound bio-enzyme catalysts through special processes. The invention adopts the following technical scheme: the compound bio-enzyme catalysts are adopted to improve the reaction rate, shorten the reaction time and simplify the production process; and molecular recombination, namely grafting, is simultaneously carried out when the required viscosity is achieved, thus improving the use performance of the starch, reducing the use quantity of the assistants and reducing COD emission. The modified starch is widely applied to such fields as disposable environment-friendly tableware, wrappers, non-woven fabrics, pulp for paper-making, industrial and agricultural membranes, fabrics warp sizing, especially to fabrics warp sizing, and can replace PVA and other size.

Methods and compositions are provided for producing nucleic acid-based compositions. Methods include enzyme catalyzed or nucleic acid polymer conjugation. Compositions include nucleic acid-containing hydrogels which can be elongated via rolling circle amplification. The hydrogels can encapsulate bioactive agents for drug delivery.

Synthetic biomaterials containing bioactive factors or modified bioactive factors that are covalently bound to the synthetic precursor components and/or biomaterials by an enzymatically degradable linkage are described herein. Further described are methods to covalently bind bioactive factors to synthetic biomaterials by means of enzymatic catalysis, the biomaterials produced therewith and the bioactive factors necessary for practicing these methods. The bioactive factors contain an amino acid sequence which can serve as a substrate domain for cross-linkable enzymes. The enzyme catalyzes the cross-linking reaction between the substrate domain of the bioactive factor and functional groups of the synthetic precursor components capable of forming the biomaterial and/or synthetic biomaterial susceptible to an enzymatically catalyzed cross-linking reaction. The biomaterials described herein may be used for localized delivery of the bioactive factors, for tissue repair and regeneration and in particular for regeneration of soft and hard tissue, such as skin, bone, tendons and cartilage.

The invention relates to a method for synthesizing salidroside by utilizing enzyme catalyzed direct glucosylation, comprising the following steps: carrying out a reaction on glucose, tyrosol and enzyme in a solvent containing a buffer solution; and collecting the salidroside by adopting the conventional method, wherein, the solvent comprises an icon-containing liquid and an organic solvent. Compared with the existing method, in the method, a reaction medium composed of the ionic liquid is adopted as a reaction system for synthesizing the salidroside by utilizing the enzyme catalyzed direct glucosylation; the enzyme activity and the enzyme stability are ensured; the dissolubility of the substrate in the reaction system is improved; the water activity in the reaction system is reduced; the expensive glucoside donor needs not to be used, and the salidroside can be further synthesized; the separation and purification processes of the product are simple, the unreacted tyrosol can be recovered and recycled, thus lowering the production cost, and satisfying the requirements of rapidly developing the medical industries.

The invention discloses a microcapsule preparation technology beneficial for quality control. The technology comprises the following steps that 1, a protein solution is prepared, wherein isolated soybean protein and an emulsifying agent are mixed and then stirred by adding water; 2, a predissolving colloid is prepared, wherein glucose and konjac glucomannan powder are added into water and stirred; 3, emulsifying is performed, wherein vegetable oil and the colloidal solution prepared in the step 2 are sequentially added into the protein solution prepared in the step 1 at the temperature of 50 DEG C-60 DEG C, stirring is performed at low speed, homogenizing is performed at high speed, and then the pH is adjusted; 4, enzyme-catalyzed gelling is performed, wherein a solidified enzyme is added for a gelling reaction; 5, vacuum freeze drying is performed, wherein microcapsule dispersion liquid obtained in the step 4 is centrifuged at low temperature at high speed and then subjected to vacuum drying for 35-50 h at the temperature of minus 30 DEG C-minus 50 DEG C under the pressure of 1.5 Pa-2.5 Pa. According to the microcapsule preparation technology beneficial for the quality control, microcapsules are dried through a low-temperature vacuum freeze drying technology, therefore, the phenomenon that the vegetable oil in the microcapsules are oxidized due to the high temperature is avoided, the nutritional value of the vegetable oil is guaranteed, and the quality of the microcapsules is guaranteed.

The invention relates to a method for preparing microcrystalline cellulose and fiber ethanol by separating furfural residues, which comprises the following steps: (1) ethanol is taken as a solvent, a circulating ultrasonic extraction method is adopted to extract, and lignin is separated from an extraction liquid; (2) extraction residues adopt complex enzyme of endoglucanase and beta-glucosaccharase for enzyme-catalyzed hydrolysis, and a hydrolysate is fermented to prepare the ethanol; and (3) hydrolysis residues are subjected to acid-catalyzed hydrolysis to separate the microcrystalline cellulose. The extraction method has the advantages that the extraction method is green and environment-friendly, the enzyme-catalyzed hydrolysis has mild conditions, the side effect is small, the acid concentration needed by acid hydrolysis is low, the action time is short, and the yield of each step is high; and the method has smart process combination, can greatly reduce the production cost for the microcrystalline cellulose and the fiber ethanol by utilizing a special structure of furfural waste residues, and has double benefits of economization and environmental protection.

The present invention relates to a multi-stage process for producing substituted, optically active alcohols, comprising an enzyme-catalyzed synthesis step, in particular a synthesis step which is catalyzed by an alcohol dehydrogenase. The inventive method is particularly suitable for producing phenylephrine, i.e. 3-[(1R)-1-hydroxy-2-methylamino-ethyl]-phenol.

An enzymatic process for preparing aliphatic polycarbonates via terpolymerization or transesterification using a dialkyl carbonate, an aliphatic diester, and an aliphatic diol or triol reactant. A catalyst having an enzyme capable of catalyzing an ester hydrolysis reaction in an aqueous environment is subsequently added to the reaction mixture. Next, polymerization of the reaction proceeds for an allotted time at a temperature≦100° C. Finally, the copolymer is isolated from an the catalyst via filtration.

Processes for the enzyme-catalyzed production of triglycerides using polyunsaturated fatty acids, in which (a) the reaction of polyunsaturated fatty acids and/or C_1-4 alkyl esters thereof with glycerol in vacuo in the presence of an immobilized enzyme to form their triglycerides is accelerated by addition of an additive from the group of weakly basic salts, complexing agents and ion exchangers and/or addition of a weakly basic salt and/or addition of an entraining agent in the form of a solvent or a gas and/or addition of glycerol-binding adsorbers and/or heat treatment of the partial glyceride intermediate product, (b) the immobilized enzymes are removed from the triglyceride by separation or filtration and (c) the remaining fatty acids and/or C_1-4 alkyl esters thereof are removed from the triglyceride by distillation, refining or extraction.

The invention relates to an (S)-chloride-3-ethyl 3-hydroxybutyrate biological preparation method, which includes: utilizing 4-chloride-3-carbonyl ethyl butyrate as substrate so that the substrate can be asymmetrically reduce to generation (S)-4-chloride-3-ethyl 3-hydroxybutyrate under the existence of biocatalyst and hydrogen donor, wherein the biocatalyst is ketoreductase KRED102, the hydrogen donor is isopropanol, the asymmetric reduction is carried in water-phase buffer solution with pH (potential of hydrogen) value of 5.0-9.0, and polyethylene glycol 400 as dispersant and divalent metal ions as enzymatic activity intensifier are added into the reaction system. By adding auxiliaries low in cost and wide in sources, the (S)-chloride-3-ethyl 3-hydroxybutyrate biological preparation method overcomes the defects of low substrate concentration and long enzyme reaction time and the like during conventional enzyme catalyzing production effectively, is simple in operation and particularly applicable to popularization and application in the pharmaceutical industry.

Esterified polysaccharides and the process of making such products are disclosed. The process can be enzymatic where an enzyme is used as a catalyst for the reaction. The process can also be chemical where no enzyme is used. Novel Products are obtained through lipase-catalyzed beta-lactone ring opening alcoholysis of ketene dimers and the process of making such compositions containing products.