149 results about "Ninhydrin" patented technology

The invention discloses a method for detecting heterotrophic bacteria content of industrial circulating water. The method comprises the following steps of: intercepting and enriching bacteria in a water sample, cracking the enriched bacteria to release protein, hydrolyzing the bacteria into amino acid, performing reactive color development on the amino acid by using ninhydrin, and comparing the measured absorbance with an 'absorbance-heterotrophic bacteria quantity' standard curve to obtain the quantity of the heterotrophic bacteria in the industrial circulating water with certain volume. The measuring method is quick and convenient compared with a national standard plate counting method, the heterotrophic bacteria content of the circulating cooling water can be acquired in short time, and the method facilitates instrumentation and automation and is easy to popularize.

The invention relates to an estrogen amino-acid ester compound with antitumor activity as well as a synthetic method thereof, effectively solving the preparation problems of the estrogen amino-acid ester compound with the antitumor activity. The synthetic method comprises the following steps of: dissolving amino acids or small molecule peptides to an aqueous solution of sodium hydroxide or a saturated solution of sodium bicarbonate, dripping carbobenzoxy chloride, making the solution react until the solution is not purple by developing with ninhydrin or carrying out film detection; washing with aether, removing aether, adjusting the pH value of the water phase with hydrochloric acid until milky white solid occurs and extracting with ethyl acetate; washing mixed solution with distilled water and saturated common salt solution, drying with anhydrous magnesium sulfate, carrying out suction filtration, concentrating and purifying; and then, mixing the mixed solution with sterides nucleus and dissolving the mixture to a reaction solvent, adding a condensing agent and a catalyst, supplementing an additional condensing agent, carrying out film detection, filtering, concentrating and purifying, dissolving in a dissolving solvent, adding palladium carbon for catalytic hydrogenation, detecting the film, filtering, concentrating and purifying. The estrogen amino-acid ester compound withantitumor activity, provided by the invention, has favorable water solubility and is superior to 2-methoxyestradiol in the tumor cell resistance action.

The present invention relates to one kind of pressure-sensitive fingerprint adhesive for detecting amino compounds; and the pressure-sensitive fingerprint adhesive contains acrylic acid grafted modified natural rubber emulsion and ninhydrin or its derivative. The present invention also relates to the preparation process of the pressure-sensitive fingerprint adhesive and the acrylic acid grafted modified natural rubber emulsion. The pressure-sensitive fingerprint adhesive is used in extracting available or latent fingerprint and footprint and has simple and reliable method and low cost.

The invention discloses a method for detecting the content of amino acids and glycyl glutamine in a compound amino acid (15) dipeptide (2) injection solution. The method comprises the following steps: precisely taking a detected sample and a reference substance solution, injecting the detected sample and the reference substance solution into a chromatographic instrument with a sulfonic group storng acid cation exchange resin LCAK06/Na column, carrying out gradient elution and regeneration balance by a mobile phase buffer solution A, a mobile phase buffer solution B and a regeneration solution, carrying out post-column derivative reaction by a derivatization reagent ninhydrin solution, recording a chromatogram map under detection wavelengths of 440nm and 570nm, and calculating according to the peak area by an external standard method. The method is capable of simultaneously detecting the content of fifteen amino acids and glycyl glutamine, and has the advantages of low cost, high speed and high sensitivity; the results of the careful methodology validation show that the method can be used for simultaneously detecting the content of amino acids and glycyl glutamine in the compound amino acid (15) dipeptide (2) injection solution; the change of the content of fifteen main chemicals in a stable sample can be inspected.

The invention provides an identification method for true and fake cubilose, which is characterized in that samples are prepared into a solution to carry out paper chromatography experiment; chromatographic solution with the volume ratio of 5:1:1:1 of normal butanol, pyridines, ethanol (95%) and water is selected and 0.5% of ninhydrin acetone solution is used for colouring; the cubilose sample solution presents purple punctum and the Rf value thereof is 0.57 by the detection; while the hogskin and agaragar of the fake cubilose has no display; therefore, the cubilose can be identified. The identification method for the true and fake cubilose is simple, convenient, quick and exact, and has little charges and extremely good practical values.

The invention discloses an extraction and purification method of alfalfa polysaccharide. The method comprises the following steps: (1) soaking alfalfa powder in water for twice, combining filtrate obtained for twice, concentrating the filtrate and then carrying out alcohol precipitation, collecting precipitates, then centrifuging or sieving the precipitates, collecting the precipitates, then adding water to dissolve the precipitates and prepare an alfalfa polysaccharide solution; and (2) successively carrying out dialysis and deproteinization treatment on the alfalfa polysaccharide solution prepared in the step (1), precipitating a system prepared by deproteinization, then centrifuging or sieving the system, collecting supernatant, carrying out alcohol precipitation, collecting the precipitates and drying the precipitates to obtain the alfalfa polysaccharide. Through the extraction and purification method of alfalfa polysaccharide, a conventional water-boiling and alcohol-extracting method of alfalfa polysaccharide is improved; the dialysis process is added; the sample is subjected to qualitative and quantitative detection by alpha-naphthol experiment, Fehling experiment, ninhydrin experiment, ferric trichloride experiment and anthranone-sulfuric acid colorimetry; the result shows that the extraction rate of the improved method reaches up to 89.87 percent.

The invention relates to an intermediate compound for use in the preparation of androst amino acid ester and a synthesis method thereof, and solves the problem of the preparation of the intermediate compound that is used in the preparation of androst amino acid ester, which is a novel antitumor compound, for keeping or increasing the antitumor activity of androst amino acid ester and increasing the water solubility of androst amino acid ester. The method comprises: dissolving amino acid or small peptides in aqueous solution of sodium hydroxide or saturated solution of sodium bicarbonate; dripping benzyl chloroformate, adding ninhydrin for color developing till no purple color or performing lamina detection; washing with diethyl ether; removing diethyl ether; regulating the pH value of water phase with hydrochloric acid till milky solid appears, extracting with ethyl acetate, washing mixed extract with distilled water and saturated table salt solution, drying by anhydrous magnesium sulfate, performing suction filtration, concentrating and purifying; and dissolving a mixture of a compound A and the mother nucleus of a steride in a reaction solvent, adding a condensing agent and a catalyst, supplying extra condensing agent, performing lamina detection, filtering, concentrating and purifying. In the invention, the method is simple and the operation is convenient.

The invention relates to a method for producing D-phenylalanine by using L-phenylalanine as a raw material. The method comprises the following steps: preparing the L-phenylalanine into 0.3-0.4kg/L aqueous solution; adjusting the pH value to 8-13 with sodium hydroxide solution; dropping acetic anhydride for acylating; controlling the reaction temperature below 40DEG C until no color displays in a ninhydrin reaction; adjusting the pH value of the acylated acetyl-L-phenylalanine to 4-6 by using hydrochloric acid; when the temperature is raised to 60-90DEG C, dropping the anhydride for racemizing; when a rotation value of a racemic liquid is less than or equal to 0.1, adjusting the pH value of the racemic liquid to 1-4 with the hydrochloric acid and cooling and crystallizing to obtain an acetyl-DL-phenylalanine crystal; preparing the obtained acetyl-DL-phenylalanine crystal into 0.04kg/L resolution liquid, adjusting the pH value to 7.8-8.2, adding 15mg/L enzyme D, preserving the heat of 40DEG C for 24 hours and stopping resolution; and extracting the resolution liquid through cation exchange resin to obtain the D-phenylalanine. The method disclosed by the invention has the advantages of simple process flow, capability of obtain high-purity products and low cost.

The invention discloses an adsorption technology for asparagine in sugarcane juice by using chitosan. The adsorption technology comprises the following steps: preparing an asparagine sucrose solution;adding chitosan and performing thermostatic waterbath oscillation; centrifuging and fetching supernate; diluting the supernate and measuring an absorbance value after the asparagine is adsorbed in anaqueous solution; calculating the adsorption quantity of asparagine, etc. According to the adsorption technology disclosed by the invention, the absorbance after the chitosan adsorbs the asparagine is measured by ninhydrin color development visible spectrophotometry; a adsorption dynamic model of chitosan to asparagine in the aqueous solution system and a sucrose solution system is fitted while aisothermal adsorption model is also studied; thus, the adsorption technology enhances the basic research for application of sugarcane juice clarification and syrup discoloration, and also has great theoretical significance and application value in raising the technological level of Guangxi sucrose industry.

The invention discloses a method for measuring main stream smoke of cigarettes by using an amino acid analyzer. The analytical method which is used for measuring ammonia in the main stream smoke of cigarettes by using the amino acid analyzer and a post column derivation device thereof is established according to the selection specificity of color development reaction of ammonia and ninhydrin and by using the design principle of the amino acid analyzer and improving an amino acid analysis method, and the problem of sodion interference puzzled by ion chromatography is successfully avoided; and the method disclosed by the invention is simple, convenient, rapid and accurate and is suitable for actual analysis and detection of a cigarette smoke sample.

The invention relates to a method for determining contents of cystine, cysteine and salt thereof in amino acid injection. The method comprises the following steps: measuring a sample to be detected and a reference solution precisely, adding 0.1-1% of sodium pyrosulfite solution, shaking up, heating by 70-100 DEG C. for 10-60 minutes, fetching out, adding formic acid 1.5 ml and 30% superoxol 1.0 ml, shaking up, placing in 30+-2 DEG C. for 30 minutes, adding water to the scale, shaking up, fetching the sample to be tested and injecting into a chromatograph with cation exchange resin, carrying out gradient elution and regeneration balance by a special-purpose mobile phase A6 solution and a special-purpose sodium hydroxide regeneration liquid, carrying out a post-column derivatization reaction by a special-purpose derivatization reagent ninhydrin solution, recording a chromatogram with the detection wavelength 570 nm, and obtaining the contents by calculating peak areas according to external standard method. The invention has the beneficial effects that (1) short analysis time and saved detection time; (2) high sensitivity; (3) low price and saved detection cost; (4) good specialization.

The invention provides a ninhydrin detection method as improvement to a free amino quantitative method in solid-phase polypeptide synthesis. Synthesized Rink_Amide_MBHA (4-Methyl-benzhydrylamine) resin is used as a standard sample and is subjected to continuous weight increment weighing to obtain a group of standard samples; and light absorption values are read under OD570 through a ninhydrin reagent reaction to acquire a standard curve; and free amino quantitative detection analysis can be performed on unknown peptide resin according to the standard curve.

The invention discloses a method for preparing bee pollen polysaccharide through combining enzymolytic wall-breaking and hot-water ultrasonic extracting. The method comprises the following steps: drying, purifying, grinding and screening bee pollen; carrying out enzymolytic wall-breaking; carrying out heating and ultrasonic extracting; dehydrating; deproteinizing with perchloric acid; carrying out (diethylamino) ethyl column chromatography and elution; separating acid polysaccharide precipitation and neutral polysaccharide precipitation with cetyl trimethyl ammonium bromide (CTAB); and dissolving the polysaccharide precipitations, then dehydrating, vacuum-freezing, and drying to obtain the high-purity impurity-free bee pollen polysaccharide. By the method, the polysaccharide extraction ratio is improved by 66.03%, and the polysaccharide yield reaches 18.54mg/g which is improved by 2.02 times compared with that of the extraction method of the prior art; and the obtained bee pollen polysaccharide liquid is negative relatively to the ninhydrin reaction, no protein residual is left, and the obtained bee pollen polysaccharide has no impurities and high purity.

The invention discloses a preparation method of L-lysine. The method comprises the following steps of: (1) adding water into L-lysine hydrochloride, mixing uniformly, and fully dissolving; (2) adding a dissolved solution obtained in the step (1) into an ion exchange column filled with cation exchange resin at the flow speed of 12-15 liters per minute, and washing with water till an effluent of the column is free from Cl<->; (3) making 1.8-2.2mol/L of NH4OH flow through the ion exchange column at the flow speed of 12-15 liters per minute, and collecting an effluent which undergoes a ninhydrin reaction, i.e., L-lysine starts flowing out when the pH value of the effluent of the ion exchange column is 8.0; and (4) concentrating a collected solution under the reduced pressure of 0.1-0.3MPa at the temperature of 60-65 DEG C for removing ammonia, decolorizing with active carbon, filtering, cooling and crystalizing to obtain L-lysine. The method has the advantages of simple process flow, no use of a large quantity of compounds or chemical reagents, low raw material price, low environmental pollution and low manufacturing cost.

The invention provides a ninhydrin post-column derivatization method for detecting histamine in fish meal. The ninhydrin post-column derivatization method comprises the following steps: preparing a to-be-detected sample solution, establishing a standard curve, and detecting by using an amino acid analyzer. According to the method, the histamine content is detected by utilizing a post-column derivatization method and setting the type, the pH value and related parameters of the buffer solution, and compared with a pre-column derivatization method in the prior art, the method is simple in pretreatment operation, short in detection time consumption and good in repeatability, and has a good popularization prospect.

The invention relates to the bio-medical field, particularly to a polypeptide separated from a deer antler base by using bioseparation engineering technology for preventing and treating diabetes. The relative molecular weight of the polypeptide is 7,127.6 daltons, the UV characteristic absorption peak is 205nm, lavender is shown on biurets reaction, and royal purple is shown on ninhydrin reaction. The polypeptide contains 16 kinds of amino acid. The polypeptide has good thermal stability and is stable in pH between 2 and 9. The polypeptide of the deer antler base is proved to have excellent effect of blood glucose reduction by the experiment of pharmacodynamics in vivo.