46 results about "Hydroxybutyrate dehydrogenase" patented technology

Disposable test strips and a wet chemistry method for measuring each of beta-hydroxybutyrate alone, combined beta-hydroxybutyrate and acetoacetate or total ketone bodies (i.e., beta-hydroxybutyrate, acetoacetate and acetone) in human bodily fluid samples, including but not limited to urine, saliva or sweat are described. The test strips need only be dipped in the sample and can be used by anyone in almost any milieu. Measurement can be made electrochemically, spectrophotometrically, fluorometrically or by comparision to a color standard. Combined acetoacetate and beta-hydroxybutyrate which account for 97-98% of total ketone bodies and may be measured in a cyclic reaction that occurs at pH about 7.0 to about 8.3 with beta-hydroxybutyrate dehydrogenase, (beta-HBD), nicotinamide adenine dinucleotide, a tetrazolium dye precursor and an electron mediator. Using this reaction, false positive results obtained from urine samples taken from patients on sulfhydryl drugs are avoided. beta-HBD from some sources was found to cause false negative results in samples (e.g. urine) containing high chloride content due to chloride inhibition of beta-HBD. Using a simple test for chloride inhibition, it was found that beta-HBD from Alcaligenes is not so inhibited. Using either beta-HBD that is not inhibited by chloride or using 10-20 times the normal concentration of this enzyme eliminates false negatives in samples having substantial chloride content, such as urine, both in the reaction described above and in other reactions disclosed for measuring each of beta-hydroxybutyrate alone, combined beta-hydroxybutyrate and acetoacetate and total ketone bodies, all of which reactions occur in the pH range of about 8.6 to about 9.5.

The invention relates to the technical field of the detection of alpha-hydroxybutyrate dehydrogenase, and particularly to an alpha-hydroxybutyrate dehydrogenase reagent. The reagent R1 is prepared from a buffering solution, EDTA-2Na, alpha-ketobutyric acid, dodecyl dimethyl betaine and preservative; the reagent R2 is prepared from a buffering solution, NADH, BSA, saccharose, trehalose, mannitol, dodecyl dimethyl betaine and preservative. By adopting the PIPES buffering solution and adding the stabilizer BSA, the saccharose, the trehalose and the mannitol, the stability of the reagent is greatly improved; by adopting the ampholytic surfactant dodecyl dimethyl betaine, not only is the determination performance remarkably improved, but also the stability and interference resistance capacity of the reagent are improved.

The present invention relates to a dairy cow sub-clinical ketosis diagnosis test paper which belongs to the art of the veterinary clinical laboratory science. The present invention comprises a support cushion and a test cushion that is fixed on the support cushion; and the present invention is characterized in that the test cushion of the test paper comprises the following reagents: D-(-)-3-Hydroxybutyrate Dehydrogenase with 2270U/mg and 50mg-100mg; nicotinamide adenine dinucleotide with 300mg-500mg; diaphorase with 35U/mg-45U/mg and 500-1,000mg; NBT with 100mg-200mg; Tris Base with molecular weight 121.14 and 1.21g; oxalic acid with molecular 126 and 126mg; fucose with molecular 383 and 4-6g; and distilled water with 100ml. The dairy cow sub-clinical ketosis diagnosis test paper of the present invention is used conveniently and has the advantages of economic practicality, high sensitivity and specificity, and good stability. The test paper is used to test D-(-)-3-Hydroxybutyrate and D-(-)-3-Hydroxybutyrate sodium in the milk of the milch cow.

Known attempts using engineered bacteria to produce P(3HB-co-4HB) with carbon sources that are structurally unrelated to 4-hydroxybutyrate resulted in relatively low 4HB monomer content of 1.5 to 5 mol %. The current invention provides recombinant hosts for producing P(3HB-co-4HB) wherein the plasmid including succinate semialdehyde dehydrogenase gene (sucD gene) and 4-hydroxybutyrate dehydrogenase gene (4hbD gene) further includes pyruvate decarboxylase promoter (P_pdc). It was found that the 4HB monomer content in P(3HB-co-4HB) is significantly enhanced to be over 20 mol %, in the range of 8.8 to 23 mol %.

The invention relates to diagnosis test paper for diabetic ketosis and other symptoms of relatively high ketone body. The diagnosis test paper comprises the following reagents: (1) first-phase immersion liquid which comprises a stabilizer and a protective agent, bovine serum albumin, oxalic acid, NAD<+>, NADP<+>, diaphorase, 3-hydroxybutyrate dehydrogenase and buffer solution; and (2) second-phase immersion liquid which comprises NBT, PMS and an organic solvent. The diagnosis test paper is prepared by the following steps of: soaking filter paper in the first-phase immersion liquid, sucking redundant immersion liquid and quickly and warmly drying the soaked filter paper at the temperature of between 20 and 50 DEG C; soaking the dried filter paper in the second-phase immersion liquid and drying at the temperature of between 20 and 50 DEG C again to obtain base paper of the diagnosis test paper; and sticking the base paper on a plastic base and cutting into pieces to obtain the diagnosisreagent strips. The diagnosis test paper can be assembled into various detection devices, has the advantages of convenient operation, fast detection, good sensitivity, high accuracy and the like, cansemiquantitatively detect the 3-hydroxybutyric acid content of milk, urine and blood, and has good application prospect.

The invention discloses a detection kit for detecting the content of beta-hydroxybutyrate in serum by adopting a stable enzymatic method. The detection kit comprises a reagent R1, a reagent R2 and a Beta-HB-containing bovine serum matrix calibrator, wherein the reagent R1 contains 10-500mmol/L buffer solution with the pH value of 7.0-8.0, 1-50mmol/L LNAD<+>, 1-10mmol/L magnesium chloride, 0.1-20mmol/L nitrotetrazolium blue chloride, 1-100mmol/L stabilizer and 0.1-2% of a preservative; the reagent R2 contains 10-500mmol/L buffer solution with the pH value of 7.0-8.0, 0.5-5KU/L beta-hydroxybutyrate, 0.5-10KU/L diaphorase, 1-45mmol/L saccharose, 10-30mmol/L EDTA, 1-100mmol/L stabilizer and 0.1-2% of a preservative. The reagents have the excellent stability and the long preservation time.

The invention discloses a kit for detecting glucose by using a glucose dehydrogenase method, and belongs to the kit for detecting glucose containing enzymes. The kit disclosed by the invention comprises 4 bottles of glucose dehydrogenase method reagents and a glucose standard solution. The kit disclosed by the invention comprises 8.0mmol/L of sodium oxalate dissolved in the phosphate buffer solution of which the concentration is 120.0mmol/L, 6000U/L of glucose dehydrogenase, 180U/L of mutarotase, 4.0 mmol/L of NAD + (Nicotinamide Adenine Dinucleotide), and 0.2% of ProClin300 preservative. In the determination, the sodium oxalate inhibits activities of endogenous lactate dehydrogenase and alpha-hydroxybutyrate dehydrogenase to control interfere reaction, so as to increase the specificity of the reaction, and improve the accuracy of detection results. The kit disclosed by the invention is less affected by a sample/reagent volume ratio during a detecting process, and the linear range is up to 35.0mmol/L. The use method of the kit is identical with the original glucose dehydrogenase method, so that the kit does not increase the burden on an experimenter, and almost does not increase the cost of the reagent, is economical, convenient and easy and is the kit for determining glucose by using glucose dehydrogenase method with high accuracy.

The invention discloses a composite stabilizer for an alpha-hydroxybutyric dehydrogenase assay kit. The composite stabilizer contains a variety of ingredients, such as a buffer solution, protein, a chelating agent, polyol and a preservative, and contains the ingredients by content: 3-9g/L of trihydroxymethyl aminomethane, 40-60g/L of disodium edetate, 20-30g/L of trehalose, 10-30g/L of bovine serum albumin, 10-20g/L of glycerine, 15-25g/L of polyvinyl pyrrolidone and 1-10g/L of Proclin300. Through the manner, by applying the composite stabilizer disclosed by the invention to the alpha-hydroxybutyric dehydrogenase assay kit, the accuracy of assay results is high, the stability is good, and the bottle opened effective period is prolonged. In addition, the composite stabilizer is low in cost and simple in preparation, thereby being worthy of further popularization.

The invention discloses genetic engineering bacteria for producing PHA (polyhydroxyalkanoates) from acetic acid and propionic acid as well as a construction method and an application of the genetic engineering bacteria. The method for preparing the engineering bacteria for producing PHA comprises the following steps: improving expression and/or activity of acetokinase, phosphotransacetylase, PHA synthetase, beta-ketothiolase, acetoacetyl-CoA reductase, succinate hemiacetal dehydrogenase, 4-hydroxybutyrate dehydrogenase, 4-hydroxybutyl CoA:CoA-transferase and propionyl CoA transferase in recipient bacteria, and reducing expression and/or activity of non-CoA-cycle succinate hemiacetal dehydrogenase in the recipient bacteria to obtain the engineering bacteria for producing PHA, wherein the recipient bacteria can grow with acetic acid as a carbon source. The prepared engineering bacteria are used for producing PHA with acetic acid as the carbon source, PHA yield can reach a higher level, and the bacteria have better industrial application prospect. The genetic engineering bacteria have great application value.

The invention discloses a reagent kit for detecting glucose by a hexokinase method, which belongs to a reagent kit in a method for detection glucose containing enzyme. The reagent kit comprises four bottles of reagent I, one bottle of reagent II, and one glucose standard liquid, wherein the reagent I comprises oxalate with the concentration of 8.0mmol/L. By inhibiting the activities of endogenous lactate dehydrogenase and alpha-hydroxybutyrate dehydrogenase through the oxalate, the reagent kit controls an interference reaction, increases the specificity of the reaction, and improves the accuracy of detection results. The reagent kit is slightly affected by the volume ratio of sample reagents and the reaction time during the detection, and the linear range can reach 37.4mmol/L. A use method and the range of the reagent kit are the same as those of the prior hexokinase method; and the reagent kit can not increase the burden of experimental personnel, almost does not increase the cost of reagents, is economical, convenient and easy, and is the reagent kit which detects the glucose by the hexokinase method with higher accuracy.

The invention discloses an alpha-hydroxybutyrate dehydrogenase detection kit. The alpha-hydroxybutyrate dehydrogenase detection kit comprises a reagent R1 and a reagent R2 which are independent to each other, wherein the reagent R1 is prepared from the following components including a biological buffering liquid 1, a metal ion complex, an alpha-hydroxybutyrate dehydrogenase reaction substrate, a surfactant 1 and a preservative 1; the reagent R2 is prepared from the following components including a biological buffering liquid 2, nicotinamide adenine dinucleotide reduced state, an activator, a surfactant 2 and a preservative 2. As adopting a mode of double reagents, the alpha-hydroxybutyrate dehydrogenase detection kit is high in detection sensitivity, low in detection limit, wide in linear test range, high in accuracy, good in repeatability, good in stability and strong in interference resistance, can be used for semi-automatic and fully automatic biochemical analyzers, is suitable for clinic popularization and application and in particular is capable of realizing rapid diagnosis of emergency treatment; the needed detection instruments (the biochemical analyzers) are generally used in various big hospitals and inspection centers.

The invention relates to the technical field of ethanol detection of blood serum and in particular relates to an enzyme-method ethanol (ALC) detection reagent with a high anti-interference capability and high accuracy. A reagent R1 is mainly prepared from a buffering solution, ammonium oxalate, hydrazine hydrochloride, potassium nitroprusside, an ion balancing agent, ascorbic acid oxidase, a protecting agent, a surfactant, NAD (Nicotinamide Adenine Dinucleotide) and a preservative; a reagent R2 is mainly prepared from a buffering solution, a protecting agent, a heavy meal ion chelating agent, alcohol dehydrogenase and a preservative. The ammonium oxalate and the hydrazine hydrochloride are added into the reagent R1 so that interference caused by lactic dehydrogenase and hydroxybutyrate dehydrogenase can be effectively removed; less potassium nitroprusside is added so that interference caused by reducing substances including bilirubin and the like is effectively removed, so that the anti-interference capability of the reagent is greatly improved; the ascorbic acid oxidase is added so that interference caused by ascorbic acid can be effectively removed; the heavy metal ion chelating agent aminotriacetic acid is added so that interference caused by heavy metal ions, especially calcium ions, on dehydrogenase activity is removed very well, so that the activity of the alcohol dehydrogenase is improved, and the reagent becomes one detection reagent with the high anti-interference capability and the high accuracy.

The invention discloses a kit for determination of alpha-hydroxybutyrate dehydrogenase and a preparation method thereof, wherein the kit includes double-liquid components of a reagent R1 and a reagent R2 which are independent with each other and includes the components and the corresponding content: the reagent R1 including 1-350 mmol/L of a buffer liquid, 0.01-10 mmol/L of alpha-ketone butyric acid, 0.1-2 g/L of disodium ethylenediamine tetraacetate, 0.01-0.40 g/L of a stabilizing agent, and a solvent being purified water; and the reagent R2 including 1-350 mmol/L of a buffer liquid, 0.1-4.0 mmol/L of NADH, 0.01-0.40 g/L of a stabilizer, and a solvent being purified water. The preparation method includes the steps: according to the following component content, preparing the reagents; mixing a to-be-tested sample with the reagent R1 and the reagent R2, and carrying out full reaction; determining the absorbance difference value after the reaction with a fully automatic biochemical analyzer; and calculating the concentration of the alpha-hydroxybutyrate dehydrogenase in the sample according to the absorbance change value. The kit has the advantages of high accuracy, good precision and the like.

The invention discloses a kit for detecting D-3-hydroxybutyric acid and a preparation method of the kit .The kit comprises a kit body composed of two independent liquid components, namely a reagent R1 and a reagent R2 .The reagent R1 is prepared from 20-180 mmol/L of buffer solution, 0.1-4.9 KU/L of D-3-hydroxybutyric acid dehydrogenase, 0.1-6.0 mL/L of polypropylene oxide and polyoxyethylene copolymer and 0.01-0.059 mmol/L of preservative, wherein solvent is purified water; the reagent R2 is prepared from 10-40 mmol/L of oxalate, 0.1-4.9 mmol/L of NAD+ and 0.01-0.059 mmol/L of preservative, wherein solvent is purified water .The invention further discloses the preparation and use method of the kit for detecting D-3-hydroxybutyric acid .The preparation and use method includes the following steps of preparing the reagents according to the contents of the components, mixing the reagent R1 and the reagent R2 with a to-be-detected sample to react sufficiently, detecting the after-reaction light absorption degree differential value through a full-automatic biochemical analyzer, and calculating the concentration of D-3-hydroxybutyric acid in the sample according to the light absorption degree change value .The kit has the advantages of being free of pollution, high in stability and the like.

The invention discloses a stabilizer for a detecting alpha-hydroxybutyrate dehydrogenase detection kit and a preparation method thereof, belonging to the in vitro diagnosis field. The stabilizer contains the following components in percentage by weight: 0.1%-0.5% of disodium edetate, 1%-3% of saccharose, 1%-2% of Triton X-100, 3%-5% of CCD, 1%-2% of glycerin, 0.1%-0.2% of liquid biological preservative Proclin300 and the balance of water. The stabilizer is applied to the detecting alpha-hydroxybutyrate dehydrogenase detection kit, so that the accuracy of a detection result of the kit is guaranteed, the detecting alpha-hydroxybutyrate dehydrogenase detection kit is relatively stable, and the preservation time of the kit is effectively prolonged. Besides, the stabilizer is low in cost, easyto prepare and worthy of being further widely popularized.

A diagnosis kit of homocysteine consists of compositions as buffer solution, serine, alpha-ketoglutaric acid, cystathionine beta-synthase, upsilon-cystathionine enzyme, homocysteine desulfydrase, hydroxybutyric dehydrogenase, glutamate dehydrogenerase, lactic dehydrogenase, reduced coenzyme and stabilizer. Its method for determining concentration of homecysteine is also disclosed.

An object of the present invention is to provide a technique for producing 1,4-butanediol by recombinant cells. Provided is a recombinant cell that is acetogenic and obligatory anaerobic, wherein the recombinant cell includes a gene encoding at least one enzyme selected from the group consisting of succinate semialdehyde dehydrogenase, succinyl-CoA synthase, CoA-dependent succinate semialdehyde dehydrogenase, 4-hydroxybutyrate dehydrogenase, 4-hydroxybutyryl-CoA transferase, 4-hydroxybutyryl-CoA reductase, 4-hydroxybutyraldehyde dehydrogenase, and alcohol dehydrogenase, the gene is expressed in the recombinant cell, and the recombinant cell produces 1,4-butandiol.

The invention discloses an alpha-hydroxybutyrate dehydrogenase detection reagent with good stability and high accuracy, and relates to the field of alpha-hydroxybutyrate dehydrogenase detection technologies. Components of a reagent R1 of the alpha-hydroxybutyrate dehydrogenase detection reagent comprise buffer solution, BSA (bovine serum albumin), 2-ketobutyric acid, EMULGEN-707, etidronic acid, octadecy trimethyl ammonium bromide, alkylphenol ethoxylates (APEO), ascorbic acid oxidase, bilirubin oxidase, sucrose, trehalose, xanthan gum and preservatives; components of a reagent R2 of the alpha-hydroxybutyrate dehydrogenase detection reagent comprise buffer solution, NADH xanthan gum and preservatives. The alpha-hydroxybutyrate dehydrogenase detection reagent has the advantages that the etidronic acid is added into the reagent R1, so that heavy metal ions can be effectively chelated, and the accuracy of the alpha-hydroxybutyrate dehydrogenase detection reagent can be effectively improved; chemical acid resistant oxidase and the bilirubin oxidase are added into the alpha-hydroxybutyrate dehydrogenase detection reagent, so that interference of ascorbic acid and bilirubin can be removed; the stabilizer BSA, the sucrose, the trehalose and the xanthan gum are added into the alpha-hydroxybutyrate dehydrogenase detection reagent, so that the stability of the alpha-hydroxybutyrate dehydrogenase detection reagent can be improved; the measurement performance of the alpha-hydroxybutyrate dehydrogenase detection reagent can be obviously improved by the aid of the alkylphenol ethoxylates (APEO) which is a novel surfactant, and the stability of the alpha-hydroxybutyrate dehydrogenase detection reagent can be enhanced.

The invention relates to a homocysteine diagnosis/determination reagent (kit) using enzyme-colorimetry and enzyme-linked method technology. Meanwhile, the invention also relates to a homocysteine concentration determination method, reagent compositions and components, which belong to the technical filed of medical test and determination. The reagent (kit) of the invention mainly includes: buffer solution, reduced coenzyme, trimethyl amino acetate salt, betaine-homocysteine methyltransgerase, methionine Gamma-catenase, hydroxybutyric acid dehydrogenase and stabilizing agent; samples and reagent are mixed according to a certain volume ratio to generate a series of enzymatic reactions; then the reactants are arranged under an ultraviolet/visible light analyzer to detect the decreasing degree of absorbance at the 340nm position of a dominant wave so as to measuring and calculating the concentration of the homocysteine.

The invention relates to a biological enzyme catalysis method for preparing 7-ketolithocholic acid at low cost. The biological enzyme catalysis method comprises the following steps that threonine is catalyzed by threonine deaminase to prepare 2-ketobutyric acid; the 7-ketolithocholic acid is generated under the action of 7alpha-hydroxysteroid dehydrogenase, alpha-hydroxybutyrate dehydrogenase, chenodeoxycholic acid and coenzyme NAD <+> by using the 2-ketobutyric acid as an auxiliary substrate; and the conversion rate of enzyme catalysis can reach 99.5% or above. The cost of the method is greatly superior to that of an existing process route, so that the biological enzyme catalysis method has the potential of industrial application.

The invention provides a kit of detecting D-3-hydroxybutyric acid through an enzymic method. The kit is composed of a first reagent and a second reagent according to the volume part ratio of 3:1. 3L of the first reagent includes 10-200 mmol/L of a buffer liquid, 50-200 U/L of a D-3-hydroxybutyric dehydrogenase, 1-3 g/L of Brij35 (dodecyl polyglycol ether), 0.1-2 g/L of sodium azide, and deionized water being added to the components until the total volume is 3L; and 1L of the second reagent includes: 10-200 mmol/L of oxalate, 0.1-10 mmol/L of 3-acetylpyridine nicotinamide adenine dinucleotide, 0.1-2 g/L of sodium azide, and deionized water being added to the components until the total volume is 1L. The kit has strong performance of resisting bilirubin interference, has high reagent sensitivity, is improved in detection accuracy and has great clinical application value.