91 results about "B-Hydroxybutyrate" patented technology

A reagent is suitable for measuring the concentration of an analyte in a hemoglobin-containing biological fluid, such as whole blood. The reagent comprises dehydrogenase enzyme that has specificity for the analyte, NAD, an NAD derivative, pyrrolo-quinoline quinone (PQQ), or a PQQ derivative, a tetrazolium dye precursor, a diaphorase enzyme or an analog thereof, and a nitrite salt. The reagent causes dye formation that is a measure of the analyte concentration. The nitrite salt suppresses interfering dye formation caused non-enzymatically by the hemoglobin. Preferably, the reagent is used in a dry strip for measuring ketone bodies, such as beta-hydroxybutyrate.

Beta-hydroxybutyrate mineral salts in combination with medium chain fatty acids or an ester thereof such as medium chain triglycerides were used to induce ketosis, achieving blood ketone levels of (2-7 mmol / L), with or without dietary restriction. The combination results in substantial improvements in metabolic biomarkers related to insulin resistance, diabetes, weight loss, and physical performance in a short period of time. Further, use of these supplements to achieve ketosis yields a significant elevation of blood ketones and reduction of blood glucose levels. Use of these substances does not adversely affect lipid profiles. By initiating rapid ketosis and accelerating the rate of ketoadaptation, this invention is useful for the avoidance of glucose withdrawal symptoms commonly experienced by individuals initiating a ketogenic diet, and minimizes the loss of lean body mass during dietary restriction.

Beta-hydroxybutyrate mineral salts in combination with medium chain fatty acids or an ester thereof such as medium chain triglycerides were used to induce ketosis, achieving blood ketone levels of (2-7 mmol / L), with or without dietary restriction. The combination results in substantial improvements in metabolic biomarkers related to insulin resistance, diabetes, weight loss, and physical performance in a short period of time. Further, use of these supplements to achieve ketosis yields a significant elevation of blood ketones and reduction of blood glucose levels. Use of these substances does not adversely affect lipid profiles. By initiating rapid ketosis and accelerating the rate of ketoadaptation, this invention is useful for the avoidance of glucose withdrawal symptoms commonly experienced by individuals initiating a ketogenic diet, and minimizes the loss of lean body mass during dietary restriction.

The invention discloses a degradable paper plastic composite bag including a plastic layer and a paper layer, the plastic layer is arranged on the surface of the paper layer, the plastic layer includes starch, vegetable fibre, polyvinyl alcohol, poly Beta-hydroxybutyrate, polyethylene, polycarbonate, nanometer titanium dioxide, glycerin, a plasticizer, and a stabilizing agent. The degradable paper plastic composite bag has excellent photodegradation and biodegradation properties, and is mild in degradation conditions and short in degradation time. The nanometer titanium dioxide in the plastic layer further improves the ultraviolet resistance capability of the plastic layer on the basis of having excellent degradability. In addition, the preparation method of the degradable paper plastic composite bag is simple in step and the degradable paper plastic composite bag can be produced industrially in batch because the raw materials are easy to get.

The invention discloses a liquid stable kit for measuring beta-hydroxybutyric acid by a cyclic enzyme method. The liquid stable kit consists of a reagent 1 and a reagent 2, wherein 1L of reagent 1 comprises 50 to 500mmol of buffer solution, 1 to 5KU of beta-hydroxybutyrate dehydrogenase, 1 to 5KU of diaphorase, 0.1 to 100g of surfactant, 1 to 100mmol of stabilizer, 0.1 to 100g of anti-interference agent I, 0.1 to 100g of anti-interference agent II, and 0.1 to 100ml of preservative; and 1L of reagent 2 comprises 50 to 500mmol of buffer solution, 1 to 20mmol of coenzyme I, 0.1 to 10mmol of nitrotetrazolium blue, 1 to 100mmol of stabilizer and 0.1 to 100ml of preservative. The liquid stable kit has the advantages of stability, wide linear range, high measurement accuracy, high antijamming capability and low cost.

The invention discloses a postpartum new dairy cow drenching nutritious supplementary and application thereof in a nutritious supplementary for treating postpartum hypocalcemia, abomasum displacement or ketosis disease of dairy cow. The nutritious supplementary provided by the invention is capable of effectively maintaining the levels of blood calcium, blood magnesium and glucose and reducing the levels of NEFA (Non-Esterified Fatty Acid) and beta-hydroxybutyric acid, thereby effectively reducing the occurrence rate of metabolic diseases of postpartum paralysis, ketosis, abomasum displacement and the like of new dairy cow. As a result, the dairy cow can be rehabilitated in physical power and food intake quickly, and the health condition of the dairy cow can be improved and the milk yield of the dairy cow can be increased; and good economic benefit can be achieved.

The invention discloses a biodegradable composite oxygen-barrier film and its preparation method and use. The biodegradable composite oxygen-barrier film is composed of at least two support layers and barrier layer which is located in each of the two support layers. Said support layer is selected from at least one of the following materials: polylactic acid, polybutylene succinate, polycaprolactone, poly(butylene adipate-co-terephthalate), poly(beta-hydroxybutyrate) and poly(beta-hydroxybutyrate-co-hydroxyvalerate); said barrier layers located in each of the two support layers are same or different, and the barrier layer is selected from poly(1,2-propylene carbonate) and nano-montmorillonite modified poly(1,2-propylene carbonate). The biodegradable composite oxygen-barrier film can be used as food or medicine package, and it will help to prolong shelf-life of food and medicine and the like; it can also prevent white-pollution.

Methods of prognosis and monitoring of breast cancer include determining the level of one or more of the markers comprising asymmetric dimethyl arginine (ADMA), beta-hydroxybutyrate (BHB) and microRNA-31 (miR-31) in patient samples. An increased level is correlated with poor prognosis. Breast cancer is treated by administration of one or more inhibitors of ADMA and / or BHB.

The invention provides a kit for detecting urinary lactic acid, creatine and beta-hydroxybutyric acid of human urine simultaneously, comprising a urine purification unit and a dry chemical reaction unit, wherein the urine purification unit is provided with a selective absorbent with combination of neutral alumina and activated carbon in weight ratio of 0.2-1:0.1-2, wherein the activated carbon is soaked by sodium hydroxide with concentration of 10-20%, and the selective absorbent is baked in a closed in a drying oven at the temperature of 70-250 DEG C for 4-72h; and the dry chemical reaction unit is a reaction box with a urinary lactic acid detection hole, a creatine detection hole and a beta-hydroxybutyric acid detection hole. The invention can detect concentration of urinary lactic acid, creatine and beta-hydroxybutyric acid of human urine simultaneously quickly and easily without help of other instruments and professional personnel so as to obtain qualitative or semiquantitative results.

Ketogenic compositions including a non-racemic mixture of beta-hydroxybutyrate (BHB) enriched with the S-enantiomer are formulated to control ketone body levels in a subject. The non-racemic mixture of BHB is enriched with the S-enantiomer to modulate the effect of ketone bodies in the subject and control the rate at which ketosis is achieved. In some aspects a composition for controlling ketone body level in a subject contains a dietetically or pharmaceutically acceptable carrier and a non-racemic mixture of S-beta-hydroxybutyrate and R-beta-hydroxybutyrate, wherein the non-racemic mixture contains from about 52% to 99% by enantiomeric equivalents of S-beta-hydroxybutyrate enantiomer and from about 48% to about 1% by enantiomeric equivalents of R-beta-hydroxybutyrate enantiomer.

The invention provides a method for measuring beta-hydroxybutyric acid by using enzyme colorimetric reaction, a matched kit and application thereof. Under the system of Tris-HCL buffer solution, serum beta-hydroxybutyric acid and coenzyme I are dehydrogenized under the catalysis of beta-hydroxybutyric acid dehydrogenase to generate acetoacetic acid and reduced coenzyme I, the generated reduced coenzyme I and iodonitrotetrazole chloride are reacted under the catalysis of diaphorase to generate a red substance formazane of which the highest absorbance is 505 nanometers, and then the content of the beta-hydroxybutyric acid in a biological sample is quantified by measuring the change of the absorbance of the red product at the wavelength of 505 nanometers. The method can linearly measure the concentration range (0 to 4.5 mmol / L) of the beta-hydroxybutyric acid in the biological sample, the measurement is used for judging the human ketosis for acid poisoning diagnosis, the reagent used by the method is liquid dual-reagent, and the quantity of the sample required for measuring the beta-hydroxybutyric acid is little; moreover, the reaction time during measuring is short, the operation is simple, and the method is suitable for mass detection.

The invention relates to stabilized beta-hydroxybutyric acid detection test paper and a preparation process thereof. The stabilized beta-hydroxybutyric acid detection test paper consists of a whole blood filter layer, a developing layer and a base layer which are sequentially stacked, wherein the whole blood filter layer is formed by combining at least one polymer film layer; the developing layer is made of a hydrophilic material; and the base layer is made of an insoluble supportive material. The method for preparing the stabilized beta-hydroxybutyric acid detection test paper comprises the following steps of: a, soaking the developing layer into reagent solution for 2 hours, taking the soaked developing layer out, and drying the soaked developing layer by cold air; and b, cutting the whole blood filter layer, the soaked and dried developing layer and the base layer into the same specifications, and sequentially bonding the layers with glue from top to bottom. The test paper is not limited by conditions such as region and the like; patients can conveniently perform self-monitor at any time and at any place; the concentration of beta-hydroxybutyric acid can be detected in a short time by only using micro blood; and the test paper is simple to prepare and has wide market value.

The invention discloses a biological sewage treatment device and a biological sewage treatment method for synchronous nitrogen and phosphorus removal and sludge reduction. The device comprises a water inlet pipe 1, an anaerobic pond 2, a mid-sedimentation tank 3, an intermediate pool 4, a BAF 5, an anoxic pond 6, a post-aeration tank 7, a secondary sedimentation tank 8, and a water outlet pipe 9 in series connection in order; the treatment process comprises the following steps: mixing raw water and P-rich returned sludge in the anaerobic pond, wherein denitrifying phosphorus accumulating bacteria (DPBs) absorb and store VFA in a body in a form of PHB (poly-beta-hydroxybutyrate) and release a large amount of phosphorus; removing VOD remained in the BAF and nitrating the nitrogen; introducing BAF nitrification liquid and the sludge in the mid-sedimentation tank into the anoxic pond together, wherein the DPBs performs denitrification for absorbing the phosphorous by using the PHB in the body as an energy source and a carbon source and using NO3<-> as an electron acceptor; removing the unnecessary phosphorus contained in the post-aeration tank and blowing off the nitrogen to prevent the sludge from floating upwards; discharging the supernatant in the secondary sedimentation tank, wherein part of the sludge containing a large amount of DPBs is refluxed and the remaining sludge is discharged. The biological sewage treatment device and the biological sewage treatment method for the synchronous nitrogen and the phosphorus removal and the sludge reduction resolves the conflict between the denitrification and the phosphorous removal, and ensures the stable water quality of effluent and low yield of the sludge.

The invention belongs to the field of medicinal packaging and discloses a biodegradable barrier-type medicinal packaging bottle. The biodegradable barrier-type medicinal packaging bottle is prepared from poly-beta-hydroxyl butyrate, barium stearate, talcum powder, zeolite powder, corn starch, methyl cellulose, polylactic acid, glycerine, ethylene glycol, oligopeptide and polyglycolic acid. The packaging bottle disclosed by the invention is good in degradability and good in barrier effect and is environment-friendly and pollution-free, and the degradation ratio can reach 98%.

The method for synthesizing completely-degradable plastics poly beta-hydroxybutyrate includes the folloiwng steps: adopting acetaldehyde as raw material to prepare beta-hydroxybutanal; oxidizing it to prepare beta-hydroxybutyric acid; esterifying it to prepare ethyl beta-hydroxybutyrate and polymerizing it to prepare poly beta-hydroxybutyrate. It is characterized by that preparation of beta-hydroxybutanal adopts benzene as solvent, sodium hydroxide as catalyst, its reaction temp. is 1-15 deg.C and the organic acid is used as neutralizing reagent, the preparation of beta-hydroxybutyric acid adopts ethyl acetate as solvent, cobalt acetate as catalyst, its reaction temp. is 40-100 deg.c and reaction pressure is 0.3-1.5 MPa, the preparation of ethyl ebeta-hydroxybutyrate adopts cresulsulfonicacid as catalyst and ethyl alcohol as solvent and polymerization preparation of beta-hydroxybutyrate uses isopropyl titanate as catalyst.

The invention belongs to the technical field of powdery paint, and particularly relates to self-catalysis fast curing type pure polyester resin, and further discloses a preparation method of the elf-catalysis fast curing type pure polyester resin and a purpose of the elf-catalysis fast curing type pure polyester resin for preparing outdoor TGIC powder paint. The self-catalysis fast curing type pure polyester resin is prepared by using terephthalic acid, 1,4-naphthalic acid, trimethyl-1,6-hexanediol, neopentyl glycol, 1,2,4-butanediol, gamma-trimethylamine-beta-hydroxybutyric acid, N,N,N-trimethyl-2-hydroxyhexadecyl ammonium chloride and glycol bis(2-aminoethyl ether) tetraacethyl as raw materials through polymerization. The self-catalysis performance of the polyester resin is prominent; the curing activity is high; under the condition without additionally adding a curing accelerant, the fast curing with a curing agent TGIC can be realized. A curing membrane prepared by the self-catalysis fast curing type pure polyester resin has excellent performance; the performance in all aspects better reaches the use requirements of outdoor pure polyester resin.

The invention relates to a strengthening method of poly-belt-hydroxy butyrate to larva of artemia. The strengthening method is characterized in that: when the larva of the artemia is strengthened by the poly-belt-hydroxy butyrate, the concentration of the poly-belt-hydroxy butyrate is 100mg / L, the strengthening time is 24h, and the grain size of the poly-belt-hydroxy butyrate is 10-50 mu m. The poly-belt-hydroxy butyrate (PHB) is the biological control agent which is wide in application prospect and can replace the antibiotic, and the research of the application of the poly-belt-hydroxy butyrate in the aquiculture is under the infancy stage at home currently and firstly. The strengthening method shows the influence of the PHB with different concentrations and the different strengthening and cultivating times to the survival rate and the growth of the larva, and is best in the strengthening effect to the larva of the artemia by 100mg / L PHB within 24 hours, so that the strengthening method has a good guide meaning for researching the application of the PHB in aquatically seedling.

Disclosed herein are “ketonnabidiol” compositions including a combination of: (1) cannabidiol (CBD) and / or cannabidiolic acid (CBDA); (2) a ketone body component such as beta-hydroxybutyrate (BHB) and / or acetoacetate; and (3) a dietetically or pharmaceutically acceptable carrier. Also disclosed herein are methods of using such ketonnabidiol compositions for producing desired physiological effects, such as fat loss, in a mammal. The ketonnabidiol compositions beneficially enhance fat loss through ketosis while also reducing the duration and / or severity of unpleasant “keto flu” symptoms typically associated with ketosis.

The invention provides a composition containing L-carnitine and a beta-hydroxybutyric acid compound, and specifically provides a composition containing the L-carnitine and at least one beta-hydroxybutyric acid compound. The beta-hydroxybutyric acid compound comprises beta-hydroxybutyrate, a beta-hydroxybutyric acid precursor or a combination thereof; and preferably, the L-carnitine and beta-hydroxybutyric acid amino acid exist in the composition in a form of intramolecular salt. The invention furthermore provides a preparation method of the L-carnitine-beta-hydroxybutyrate. The composition provided by the invention is high in stability, high in bioavailability and significant in weight loss effect and ketogenic effect; and the preparation method provided by the invention is easy and convenient to operate.

The invention discloses a biodegradable peanut protein plastic with a long service life. The biodegradable peanut protein plastic comprises the following raw material in parts by weight: 30 to 35 parts of poly (3-hydroxybutyrate-co-3-hydroxyvalerate) PHBV, 55 to 60 parts of modified-beta-hydroxybutyric acid, 15 to 20 parts of peanut protein powder, 15 to 18 parts of nano cellulose whiskers, 3 t o 5 parts of amylase, 1.1 to 1.3 parts of a silane coupling agent KH590, 2 to 3 parts of sodium lactate, 0.5 to 0.8 parts of sodium dehydroacetate, 1.7 t o 2.3 parts of dioctyl terephthalate DOTP, 2 to 4 parts of octyl epoxy stearate, 25 to 28 parts of carbon black N550, 12 to 16 parts of ground calcium carbonate, 4 to 7 parts of kaolin, 10 to 12 parts of hard pottery clay, and 0.7 to 0.9 parts of an antioxidant. The peanut protein plastic can be biologically degraded into low molecular compound, is high in flexility, good in impact resistance and oxidation resistance, low in water absorption, and low in complete degradation velocity, and the service life of the biodegradable peanut protein plastic can be prolonged.

The invention discloses a poly epsilon-caprolactone / poly (beta-hydroxybutyrate-valerate) blend membrane and a preparation method thereof, and belongs to the field of biodegradable materials. The blend membrane is a membrane produced by irradiation modification by an electron beam produced by gamma rays or an electron accelerator, the irradiation dose is 2-70 kGy, the membrane thickness is 20 to 200 microns, and taking the total membrane mass as 100%, the PCL (polycaprolactone) content is 20-80%, and the PHBV (poly hydroxyl butyrate valerate) content is 20-80%. The preparation method is as follows: respectively dissolving PCL and PHBV in solvents to obtain a solution 1 and a solution 2; (2) mixing the solution 1 and the 2 solution to obtain a mixed solution3; (3) casting a glass plate with the mixed solution3 to make the thickness uniform, forming a membrane by solvent evaporation, and obtaining a blend membrane by vacuum drying to a constant weight; and (4) performing irradiation on the blend membrane. According to the blend membrane, mechanical properties of the PCL and the PHBV are complemented, the brittleness of the PHBV is improved, the degradation performance is adjustable, and the method is simple in process and less in environmental pollution.

The invention belongs to the technical field of chemical synthesis, and particularly discloses a method for preparing a biodegradable material poly-beta-hydroxybutyrate.The method includes the steps that a certain amount of ethyl 3-hydroxybutyrate, a catalyst and water are stirred evenly, then a heating reaction is performed for 2-3.5 h, and the poly-beta-hydroxybutyrate with a certain viscosity-average molecular weight is obtained.According to the method, it is unnecessary to introduce inert gas like nitrogen or argon into the reaction process, so that operation is easy and convenient.According to the technical scheme, the time of preparing PHB in a heating state does not exceed 4 h and is 1 / 2 or shorter the reaction time of other traditional methods.By means of the preparation method, the reaction time is significantly shortened, the preparation process is simplified, and the production cost is lowered.

The invention discloses a method for preparing a silicon-containing micron-fiber-toughened PHBV composite material and belongs to the field of natural polymer material-toughened biodegradable plastics. The method comprises the following steps of dispersing a silicon-containing raw material in an aqueous sodium of sodium hydroxide with mass fraction of 10-35%, holding the temperature in a temperature range of 20-40 DEG C for 4-8 hours, diluting, filtering, adding 1-5% of a dispersant, carrying out low-pressure crushing by a homogenizing apparatus at a homogenizing pressure of 100-200bar, cycling for 6-15 times, separating and carrying out vacuum drying treatment to obtain silicon-containing micron-fiber; carrying out melt blending on silicon-containing micron-fiber, poly(beta-hydroxybutyrate-beta-hydroxyvalerate) (PHBV) at a mass ratio of (1:10)-(1:25), carrying out extrusion molding and granulating to prepare the silicon-containing micron-fiber-toughened PHBV composite material. By the method, when PHBV is toughened by virtue of the plant fiber in the prior art, the problems that the plant fiber needs to be prepared into nanoscale, a large amount of chemicals and power are consumed and the process is complex can be solved. According to the method for preparing the composite material, the agricultural residues can be utilized and thus the environment friendliness is achieved.

The invention discloses a marker group for diagnosing and distinguishing coronary arterial atherosclerosis from stable angina pectoris. The marker group comprises one or more of glutathione, beta-hydroxybutyric acid, proline, fumaric acid, phenylalanine and lactic acid. When a single marker is used for diagnosing and distinguishing patients with the stable angina pectoris from patients with the coronary arterial atherosclerosis, the AUCs (areas under curve) of a ROC (receiver operating characteristic) are all 0.7 or larger, and the marker has a clinical diagnosis significance; when the markers are used for diagnosis in combination, with the increase of the combination number, the AUC is further increased and reaches 0.988 when 6 markers are combined, and the sensitivity and the specificity are 98.5% and 98.3% respectively under the optimum cutoff value. The metabolic marker group can accurately diagnose and distinguish the coronary arterial atherosclerosis from the stable angina pectoris, and is high in sensitivity and specificity.

The invention discloses a method for preparing a test paper for rapidly determining dairy cows subclinical ketosis, which comprises the following steps of: adding boric acid, aminoacetic acid and ethylene diamine tetraacetic acid solution in Arabic gum dissolved in a hot-water bath, adjusting the pH value of the prepared solution to be 7.0, soaking the test paper for 20 minutes in the prepared solution while the prepared solution is hot, drying the test paper in a drying oven at 60 DEG C, and standing the test paper in the drying oven overnight; and dissolving ethylene glycol, sodium nitroprusside and absolute ethyl alcohol in the hot-water bath, soaking the test paper for 20 minutes in the prepared solution while the prepared solution is hot, taking the test paper out, blotting moisture in the test paper by using filter paper, drying the test paper in the drying oven at 60 DEG C, and standing the test paper in the drying oven overnight so as to obtain the test paper. The reagent strip takes the concentration of beta-hydroxybutyric acid in blood more than 1.2mmol / L as a positive criteria; and the production practice proves that the reagent strip has the advantages of low cost, simple and easy operation, quick response, high specificity and high sensitivity, can be used for various determined samples such as blood, urine, serum, plasma and milk, and has wide application scope.

The invention relates to the field of rapidly diagnosing diabetic ketoacidosis. Electrochemical test paper is prepared by using a silk-screen printing process; and the content of beta-hydroxybutyrate in human blood is detected by current which is generated when beta-hydroxybutyrate is oxidized by an enzyme layer on the test paper, so as to judge whether the diabetic ketoacidosis exists or not. The enzyme layer is prepared from nitrocellulose, hydroxybutyrate dehydrogenase, glutaraldehyde, potassium ferricyanide, reduced coenzyme and chitosan. The preparation method of the enzyme layer comprises the following steps of: dissolving nitrocellulose, hydroxybutyrate dehydrogenase, potassium ferricyanide, reduced coenzyme and chitosan with a phosphoric buffered solution; then reacting with glutaraldehyde; dropwise adding a mixed solution on the test paper; and drying to finally obtain the enzyme layer of the electrochemical test paper for detecting the beta-hydroxybutyrate. The silk-screen printing electrode provided by the invention can be widely applied to rapid diagnosis of diabetic ketoacidosis.

Pharmaceutical compositions containing an effective amount of a ligand for GPR109 to decrease intracellular cAMP levels of a subject in combination with an effective amount of a DNA methyl transferase inhibito to reduce or inhibit downregulation of GPR109 in the intestinal epithelial cells of the subject relative to a control are provided. It has been discovered that ligands for GPR109 can be used to treat one or more symptoms of cancer, inflammatory disorders, and diarrhea. Representative CPR 109 ligands include, but are not limited to butyrate, β-hydroxybutyrate, nicotinic acid, acifran, and octanoate. Suitable DNA methyl transferase inhibitors include 5-azacytidine, 5-aza-2′-deoxytidine, 1-β-D-arabinfαmosyl-5-azacytosine and dihydro-5-azacytidine. Typically, the compositions are formulated to achieve a GPR 109 ligand serum blood level of about 1 to about 1000 μM. The compositions are useful for the treatment of one or more symptoms of cancer. Preferred cancers that can be treated using the disclosed compositions include, but are not limited to colon cancer, breast cancer and leukemia. Methods for treating cancer, inflammatory disorders, and diarrhea are also provided.

Provided is a composition for promoting ketone body production that comprises a water insoluble polymer of a β-hydroxy short-medium chain fatty acid such as homopolymer of β-hydroxybutyric acid or a copolymer of β-hydroxybutyric acid and β-hydroxyvaleric acid. The composition is useful for the treatment or prevention of a disease or condition that can be treated by promoting ketone body production.

The invention discloses application of a beta-hydroxybutyric acid or a pharmaceutically acceptable salt thereof, particularly discloses application of a beta-hydroxybutyric acid or a pharmaceutically acceptable salt thereof in preparation of medicines for preventing and treating diabetes mellitus and chronic complication thereof, and belongs to the technical field of medicines. A diabetes rat model is induced with streptozotocin (STZ); the prevention and treatment effects of the beta-hydroxybutyric acid on diabetes and chronic complication of rats are observed with the beta-hydroxybutyric acid through subcutaneous injection; the result shows that the weight loss of the rats can be restrained by the beta-hydroxybutyric acid; the pathology function change of chronic pancreas, great vessels, kidneys, hearts, livers and the like of the rats is improved; the beta-hydroxybutyric acid or the pharmaceutically acceptable salt thereof as an active pharmaceutical ingredient is combined with conventional additives in the field of medicines to prepare medicines; the beta-hydroxybutyric acid or the pharmaceutically acceptable salt thereof can be used for improving the diabetes and the chronic complication thereof; and clinical treatment is carried out by aiming at diseases caused by anti-oxidative stress and nitration injuries.