905 results about "Histidine" patented technology

The invention provides recombinant escherichia coli with high yield of ergothioneine and a method for preparing ergothioneine, the recombinant escherichia coli co-expresses ergothioneine anabolic enzymes Egt1 and Egt2, the methyltransferase structural domain of the Egt1 is derived from trichoderma reesei, mycobacterium smegmatis EgtD or rhizopus nigricans, and the methyltransferase structural domain of the Egt2 is derived from the trichoderma reesei, the mycobacterium smegmatis EgtD or the rhizopus nigricans. The histidine sulfoxide synthase structural domain is derived from trichoderma reesei, schizosaccharomyces pombe or rhizopus nigricans, and the Egt2 is derived from claviceps purpurea, neurospora crassa or aspergillus niger. After the recombinant escherichia coli obtained by screening is cultured for 68 hours in a 5L fermentation tank, the yield of ergothioneine can reach 5g / L or above; wherein after recombinant escherichia coli co-expressing Egt1 enzyme (the structural domain of methyltransferase is derived from mycobacterium smegmatis EgtD, and the structural domain of histidine sulfoxide synthase is derived from trichoderma reesei) and Egt2 enzyme (derived from neurospora crassa) are cultured in a 5L fermentation tank for 68 hours, the yield of ergothioneine can reach 8.7 g / L, and the production intensity reaches 127.9 mg / (L.h).

The invention discloses a formate dehydrogenase mutant and application thereof in catalytic synthesis of D-mannitol, and belongs to the technical field of bioengineering. According to the formate dehydrogenase mutant provided by the invention, the 18th-site glutamic acid of wild-type formate dehydrogenase with an amino acid sequence shown as SEQ ID NO.2 is mutated into proline, the 57th-site asparagine is mutated into glutamic acid, the 70th-site histidine is mutated into tryptophan, the 235th-site serine is mutated into threonine, and the 316th-site valine is mutated into threonine, so that the formate dehydrogenase mutant is high in enzyme activity and catalytic activity; the coenzyme circulation efficiency during the production of D-mannitol can be obviously improved, so that the yield of D-mannitol can be effectively improved. When the genetically engineered bacterium co-expressed by the formate dehydrogenase mutant and the mannitol dehydrogenase mutant is used for catalyzing 150 g / L fructose to produce D-mannitol, the yield of D-mannitol within 15 h can reach 140 g / L or above.

The invention provides a composite reagent system and a chalcopyrite and sphalerite collecting method, and belongs to the technical field of mineral processing. The composite reagent system comprises a histidine derived functional group collecting agent and a black agent, and the histidine derived functional group collecting agent (containing a total sulfur ester group, a sulfydryl functional group and a side chain imidazole ring) serves as a core and is compounded with the black agent according to a specific proportion to form a target combination-synergistic interaction flotation mechanism. The histidine derivative collecting agent derives high-activity functional groups under the alkaline condition, and after sulfydryl is dissociated, stable chemical bonds are formed by the dissociated sulfydryl and metal ions on the surfaces of the chalcopyrite and the zinc sulfide. The black powder serves as an auxiliary collecting agent, and the collecting capacity of fine-grain or low-activity sulfide minerals is enhanced through chemical adsorption of dithiophosphate radicals and metal ions on the surfaces of the chalcopyrite and the sphalerite. After the two components are compounded, the selective enrichment efficiency of copper-zinc minerals in the flotation process is remarkably improved.

The invention discloses a graphene nanometer heavy anti-corrosion coating and a preparation method thereof, and belongs to the technical field of anti-corrosion coatings. The coating is prepared from the following components in parts by mass: 50 to 70 parts of diallyl bisphenol A type epoxy resin, 8 to 15 parts of histidine modifier, 12 to 20 parts of graphene nano composite modified filler, 5 to 10 parts of curing agent, 0.5 to 2 parts of flatting agent and 0.3 to 1 part of defoaming agent. The preparation method of the histidine modifier comprises the following steps: carrying out a Schiff base reaction on 1-palmitoyl-2-oleoyl ethanolamine and N-formyl-L-histidine to generate an intermediate A; reacting with a spiro quaternization reagent to form a quaternary ammonium salt intermediate B; and then compounding with aminopropyltriethoxysilane and silicotungstic heteropoly acid salt to obtain the product. The graphene nano-composite modified filler is prepared by modifying the surface of a graphene oxide / bentonite mutual intercalation layer structure through allyl trimethoxy silane. The graphene nano heavy anti-corrosion coating prepared by the invention forms a high-density cross-linked network, and has excellent barrier property, strong adhesive force, impact resistance and long-acting anti-corrosion performance.

The invention discloses preparation of a bionic copper-based MOF nano-enzyme and application of the bionic copper-based MOF nano-enzyme in hydroquinone detection, and the bionic copper-based MOF nano-enzyme is prepared by the following method: dissolving terephthalic acid H2BDC and L-histidine His in N, N-dimethylformamide DMF to obtain a solution A; adding copper chloride CuCl2. 2H2O into the solution A obtained by C1, and stirring to form a uniform mixed solution; carrying out hydrothermal reaction on the mixed solution obtained from C2 for a certain time, centrifuging to obtain a solid precipitate, cleaning the solid precipitate, and drying to obtain the bionic Cu / His-MOF nano-enzyme; the invention also discloses an application of the sensor in hydroquinone detection. The bionic copper-based MOF nano-enzyme has the advantages of being simple and convenient to synthesize, high in substrate affinity, high in catalytic capacity and the like, and meanwhile, a rapid, sensitive and reliable HQ detection method is provided.

The invention relates to laccase as well as a mutant and application thereof, and belongs to the technical field of biology. The amino acid sequence of the laccase PnLac1 is as shown in SEQ ID NO. 2, and the nucleotide sequence of the laccase PnLac1 is as shown in SEQ ID NO. 1. The mutant is characterized in that aspartic acid at the 166th position of laccase PnLac1 is subjected to site-specific mutagenesis, histidine at the 348th position of laccase PnLac1 is subjected to site-specific mutagenesis, methionine at the 403th position of laccase PnLac1 is subjected to site-specific mutagenesis, or leucine at the 467th position of laccase PnLac1 is subjected to site-specific mutagenesis, amino acid sequences are shown as SEQ ID NO.4, SEQ ID NO.6, SEQ ID NO.8 and SEQ ID NO.10, and nucleotide sequences are shown as SEQ ID NO.3, SEQ ID NO.5, SEQ ID NO.7 and SEQ ID NO.9. The decoloring efficiency of the laccase PnLac1 on crystal violet reaches 5h, and the degradation rate reaches 75%. When the ABTS is used as a substrate, the enzyme activities of the laccase mutants H348F and L467M are respectively improved by 1.89 times and 1.65 times, and the ABTS has the potential of degrading stubborn substances; when guaiacol is used as a substrate, the enzyme activities of the laccase mutants D166A and M403F are respectively improved by 2.07 times and 3.72 times, and the guaiacol has a relatively high application prospect in the field of lignin.

The invention relates to the technical field of microorganisms, and particularly discloses a recombinant microorganism and application thereof in fermentation production of decarboxylated carnosine. Compared with an original strain, the recombinant microorganism disclosed by the invention has the advantages that the expression of the mdtK gene is enhanced; the starting strain is escherichia coli capable of producing decarboxylated carnosine. When the recombinant microorganism is used for fermentation production, the yield of the decarboxylated carnosine can be increased, L-histidine, histamine or beta-alanine and other precursors do not need to be added in the production process, and an effective novel method is provided for industrial production of the decarboxylated carnosine.

The invention relates to the technical field of biology, and discloses a carbonyl reductase mutant and application thereof in enzymatic synthesis of chiral alcohol. The amino acid sequence as shown in SEQ ID NO.2 is subjected to mutation that 36th lysine is mutated into any one of aspartic acid, threonine and valine, or / and 125th histidine is mutated into any one of lysine, serine and leucine, or 170th histidine is mutated into any one of lysine, cysteine and leucine. The carbonyl reductase mutants, especially single-site mutants Mut-T75K, Mut-T75D and Mut-E216M and a combined mutant Mut-T75K-E216M, with activity improved to different extents compared with that of a wild type are obtained, have excellent relative enzyme activity, thermal stability and substrate tolerance, have relatively high activity and stability for various chiral alcohols, and can be used for preparing the carbonyl reductase mutants. The catalyst has the advantages of high catalytic activity, high thermal stability, strong substrate tolerance, easiness in fermentation and the like.

The invention discloses a p-nitrophenyl ethyl esterase mutant with high enantioselectivity as well as a construction method and application of the p-nitrophenyl ethyl esterase mutant. The p-nitrophenyl ethyl esterase mutant is obtained by mutating an amino acid sequence of wild p-nitrophenyl ethyl esterase pnbA as shown in SEQ ID NO.1 according to one or a combination of more of the following modes: leucine at the 273rd site is mutated into aspartic acid, phenylalanine at the 314th site is mutated into histidine, and leucine at the 362nd site is mutated into arginine. The mutant pnbA-L273D / F314H / L362R provided by the invention shows optimal catalytic performance (E = 47.16) for racemization-acetic acid pinyl hydrate, the enantiomeric excess value of the mutant is 95.13%, the conversion rate of 1S, 5R-acetic acid pinyl hydrate is 90.42%, the enantioselectivity of the mutant is obviously higher than that of a wild type, and the mutant has great application potential in biological catalytic synthesis of monocyclic monoterpenoid chiral alcohols.

The invention discloses a diluent for whole blood lateral immunochromatography detection as well as a preparation method and a detection method thereof, and belongs to the technical field of immunochromatography detection. The diluent solves the technical problems of unsmooth chromatography, background interference, poor stability of detection results and the like caused by red blood cells during direct detection of whole blood samples. The diluent comprises a buffer system, an osmotic pressure regulator glycine, a nonionic surfactant polysorbate, an erythrocyte aggregation inducer polyvinylpyrrolidone, a dynamic viscosity regulator trehalose, a blocking protein, a stabilizer combination L-methionine and L-histidine, and a composite formula of water. Red blood cells are effectively induced to gather and intercept on the sample pad through the synergistic effect of all the components, and meanwhile the stability of the chromatography process and the activity of the detection reagent are maintained. The diluent is mainly used for lateral immunochromatography quantitative detection of markers such as pro-enkephalin, C-reactive protein, cardiac troponin I or N-terminal pro-brain natriuretic peptide in a whole blood sample.

The invention belongs to the technical field of immunodetection, and discloses a kit for detecting the ratio of proBDNF to maure BDNF based on structural dynamics guidance and a preparation method of the kit, the kit comprises a solid phase carrier and a detection reagent, the three antibodies are determined on the basis of full-length conformational kinetics analysis of brain-derived neurotrophic factors; the first capture antibody targets an innate disorder region (SEQ ID NO: 1) of a proBDNF propeptide region; the second capture antibody targets an innate disorder region (SEQ ID NO: 2) of a proBDNF propeptide region; the second capture antibody is a neo-epitope specific antibody, is specifically combined with an N terminal (SEQ ID NO: 2) exposed by maure BDNF enzyme digestion, and is combined with a free alpha-amino group strictly dependent on the first histidine; and the universal detection antibody is combined to a Loop 4 region (SEQ ID NO: 3) of the Mature structural domain. The problems of steric hindrance and cross reaction in traditional immunodetection are solved through a structural biology strategy, and accurate distinguishing and ratio quantification of proBDNF and maure BDNF are achieved.

The invention discloses a preparation method of an edible pectin film capable of monitoring and prolonging fruit freshness, which comprises the following steps: carrying out oxidation reaction on pectin and sodium periodate, then terminating the reaction and purifying to obtain oxidized pectin; the preparation method comprises the following steps: dissolving oxidized pectin in water, then adding histidine, and carrying out heating reaction at 60-120 DEG C for 1-3 hours to obtain a reaction product with pH-responsive fluorescence characteristics; adding a calcium chloride aqueous solution as a cross-linking agent into the reaction product, simultaneously adding glycerol as a plasticizer, stirring and mixing for 5-15 minutes at the temperature of 50-70 DEG C, and then stirring and mixing for 1.5-2.5 hours at the temperature of 20-30 DEG C to obtain a uniform film forming solution; pouring the film-forming liquid into a film, and drying to obtain an edible pectin film; the invention also provides the edible pectin film prepared by the preparation method. The prepared edible pectin film is mainly used for packaging fruits, and the freshness of the fruits can be visually displayed through fluorescence change while the fruits are kept fresh.

The invention relates to the field of agricultural protection preparations, in particular to preparation of gold nanoclusters and application of the gold nanoclusters to prevention and treatment of plant parasitic nematodes. The invention provides a preparation method of a gold nanocluster, which comprises the following steps: preparing by using HAuCl4 and L-His to obtain an L-type histidine modified gold nanocluster; the preparation method comprises the steps that a HAuCl4 aqueous solution and an L-His aqueous solution are evenly mixed and then incubated, an obtained reaction solution containing L-His-AuNCs is centrifuged and then subjected to aftertreatment such as ultrafiltration, and the gold nanocluster is obtained. The gold nanocluster can be used for preventing and treating pine wood nematodes.

The present invention relates to a highly concentrated, stable pharmaceutical formulation of a pharmaceutically active anti-HER2 antibody, such as e.g. Trastuzumab (HERCEPTIN™), Pertuzumab or T-DM1, or a mixture of such antibody molecules for subcutaneous injection. In particular, the present invention relates to formulations comprising, in addition to a suitable amount of the anti-HER2 antibody, an effective amount of at least one hyaluronidase enzyme as a combined formulation or for use in form of a co-formulation. The formulations comprise additionally at least one buffering agent, such as e.g. a histidine buffer, a stabilizer or a mixture of two or more stabilizers (e.g. a saccharide, such as e.g. α,α-trehalose dihydrate or sucrose, and optionally methionine as a second stabilizer), a nonionic surfactant and an effective amount of at least one hyaluronidase enzyme. Methods for preparing such formulations and their uses thereof are also provided.

The invention belongs to the technical field of nano-enzymes, and particularly relates to a CuPH (at) KMO composite nano-enzyme material as well as a preparation method and application thereof. Aiming at the problems of poor catalytic activity, complex steps, high raw material cost and low biocompatibility of nano-enzyme prepared by the existing method, the preparation method comprises the following steps: by taking terephthalic acid and histidine as dual-coordination copper-based nano-enzyme as a precursor, introducing manganese oxide in situ under a hydrothermal condition; and the flower-like nano mimic enzyme which is uniform in size and has high laccase-like catalytic characteristics at the same time is synthesized. The composite nano-enzyme provided by the invention can catalytically oxidize phenol amine organic compounds under the condition that the pH value is 3-9, can realize the detection of the content of ergothioneine in cosmetics and nutritional supplement capsules, and can be applied to the field of cosmetic and food safety monitoring.

The invention discloses a preparation method of a metal doped type hydroxyapatite nanoflower. The method specifically comprises the following steps: dispersing a calcium source and soluble metal salt into water, adding acid phosphate, urea and L-histidine, uniformly mixing, carrying out a hydrothermal reaction, mechanically stirring, filtering, washing, and drying a hydrothermal system precipitate to obtain the corresponding metal-doped hydroxyapatite nanoflower. Compared with the prior art, the metal-doped hydroxyapatite nanoflower prepared by the preparation method disclosed by the invention is directly assembled by nanosheets, and a single metal type can be doped in a customized manner. According to the method, water is used as a unique solvent, the use of an organic solvent is avoided, the pH does not need to be adjusted in advance, the technological process is simple, operation is convenient, equipment investment is small, and the method is suitable for industrial production.

The present application relates to a pyridoxal kinase mutant, a recombinant expression vector and a microbial cell and their applications, and belongs to the technical field of biological catalysis. In order to solve the problem of low product concentration in existing enzyme catalysis, a pyridoxal kinase mutant is provided, the amino acid sequence is selected from the amino acid sequence shown in SEQ ID NO. 1, the lysine at position 229 is mutated to alanine, phenylalanine, methionine, arginine, threonine, histidine, serine, tyrosine, valine, leucine, isoleucine, proline, asparagine, aspartic acid or glutamic acid; the pyridoxal kinase mutant is used for catalyzing pyridoxal to synthesize pyridoxal phosphate, and a recombinant expression vector and a microbial cell can be further formed. The present application has good enzyme activity, high product conversion rate, high concentration of pyridoxal phosphate obtained, and the concentration of the product catalyzed by the wild-type pyridoxal kinase to phosphorylate pyridoxal is obviously improved.

The invention discloses bovine lactoferrin freeze-dried powder and a preparation method thereof, and belongs to the technical field of protein freeze-drying. The preparation method of the bovine lactoferrin freeze-dried powder comprises the following steps: adding a histidine buffer solution into a bovine lactoferrin solution with the mass concentration of 30-40%, and mixing to obtain a mixed solution; adding a freeze-drying auxiliary material accounting for 0.25-7.0% of the volume of the mixed solution into the mixed solution to obtain a bovine lactoferrin freeze-drying solution; performing spray freezing and freeze drying on the bovine lactoferrin freeze-dried liquid to obtain bovine lactoferrin freeze-dried powder; the freeze-drying auxiliary materials comprise a surfactant, amino acid, D-chiro-inositol and calcium chloride. Compared with the traditional inositol, the D-chiral inositol in the freeze-dried auxiliary material can more effectively replace water molecules, maintain the natural conformation of protein and prevent the bovine lactoferrin structure from collapsing. The calcium chloride in the freeze-drying auxiliary material can stabilize the iron binding area of the bovine lactoferrin in the freeze-drying process, and the biological activity of the bovine lactoferrin after freeze-drying is guaranteed.

The invention discloses a chitosanase mutant which is derived from bacillus subtilis and has the capacity of hydrolyzing chitosan to produce chitosan disaccharide per unit and belongs to a GH46 family, and application of the chitosanase mutant in hydrolyzing chitosan to produce chitosan oligosaccharide. Compared with wild type chitosanase capable of producing chitodisaccharide and chitotriose, the chitosanase mutant has the advantage that the chitodisaccharide can be produced per unit when the chitodisaccharide is hydrolyzed by the chitosanase mutant. The invention provides eight kinds of chitosanase mutants, and the mutants are obtained by carrying out site-specific mutagenesis on 21st-site glycine on the basis of wild type chitosanase and respectively mutating the 21st-site glycine into lysine, arginine, leucine, histidine, methionine, tyrosine, proline and glutamine. The mutant can hydrolyze chitosan under mild conditions to produce chitosan oligosaccharide with single polymerization degree, and can greatly relieve the difficulty in separation and purification in chitosan oligosaccharide production.

The invention discloses a nano compound based on a CRISPR-Cas9 system and application of the nano compound. The nano compound comprises a histidine oligopeptide-cell penetrating peptide conjugate and an RNP compound composed of sgRNA of a target gene and Cas9 protein, and the histidine oligopeptide-cell penetrating peptide conjugate and the RNP compound are self-assembled under the action of zinc ions to form the nano compound. The nano-composite designed by the invention is simple in structure, and overcomes the defects of high cytotoxicity and large particle size (diameter gt; compared with the prior art, the compound has the advantages that the compound can overcome the defects of complex chemical synthesis, potential immunogenicity and the like, can be used for extracellular-cytoplasm-cell nucleus trinity antivirus, is high in virus removal efficiency and good in antivirus effect, and has high market value and development potential.

The invention relates to the technical field of dried orange peel enzyme beverages, in particular to a dried orange peel enzyme beverage and a preparation method thereof. The dried orange peel enzyme beverage is prepared from the following raw materials in percentage by mass: 3-10% of dried orange peel, 0.5-2% of lemon juice, 5-15% of haws, 5-15% of pineapples, 3-10% of bitter gourds, 5-15% of red dates, 3-10% of longans, 1-5% of Chinese wolfberry fruits, 3-10% of sea-buckthorn and the balance of deionized water. According to the pericarpium citri reticulatae enzyme beverage and the preparation method thereof provided by the invention, through a specific fermentation process, the pericarpium citri reticulatae and a plurality of medicinal and edible food materials such as the hawthorn fruits, the Chinese wolfberry fruits and the bitter gourds are subjected to mixed fermentation, so that the original medicinal components of the pericarpium citri reticulatae are reserved, macromolecular substances are converted into micromolecular substances which are easily absorbed by a human body through the action of microorganisms, and the taste of the pericarpium citri reticulatae enzyme beverage is improved. The dried tangerine or orange peel beverage can be used as a raw material, such as lysine, arginine, histidine, oligosaccharide, flavonoids, polyphenols and the like, so that the innovative beverage not only enriches the variety of dried tangerine or orange peel products, but also provides a healthy and convenient health-preserving choice for modern people.

The invention relates to the technical field of biology, and discloses a recombinant carbonyl reductase mutant and application thereof in synthesis of chiral alcohol. According to the invention, the 36th-site lysine is mutated into any one of aspartic acid, threonine and valine, or / and the 125th-site histidine is mutated into any one of lysine, serine and leucine, or / and the 170th-site histidine is mutated into any one of lysine, cysteine and leucine; the carbonyl reductase mutants, especially single-site mutants Mut-K36D and Mut-H125K and a combined mutant Mut-K36D-H125K, with activity improved to different extents compared with that of a wild type are obtained, have excellent thermal stability and relative enzyme activity, have relatively high activity and stability aiming at various chiral alcohols, and can be used for preparing the carbonyl reductase. The method has the advantages of high catalytic activity, high enzyme expression quantity, easiness in fermentation and the like.

The present invention relates to a stabilized solid pharmaceutical composition comprising a GLP-1 agonist. The present invention further relates to a method for preparing such a composition and its use in medicine.

There is provided a method for diagnosing a subject with early onset muscle atrophy, said method comprising: obtaining a biosample from the subject; and assaying the biosample for one or more biomarkers, said one more biomarkers are taurine, proline, citrulline, trigonelline, thymidine, ornithine, glutamate, L-pyroglutamic acid, creatinine, adenine, nicotinamide, 2-methylhippuric acid, maltol, L-arginine, hypotaurine, L-glutamine, homogentisic acid, methylhistidine, oxoglutaric acid, xanthine, L-carnitine, succinate, or a combination thereof; and identifying the subject with early onset muscle atrophy on the basis of a deviation in the one or more of said one more biomarkers.

A major challenge in the field of antibody-based therapeutics is the development of antibodies that have longer duration of action, longer half-life and can be delivered to a patient at lower doses. The current methods to achieve this aim depend on the engineering modification of the pH-dependent antigen binding properties of the antibodies, which is very strenuous and generally requires further optimization of the pH-sensitive interactions in a low-throughput, individualized manner because these methods depend mainly on the introduction of histidine mutations in specific antibody complementarity determining regions (CDRs). In the present invention, the inventors provide antibodies and other antigen-binding proteins that carry mutations outside of the complementals, thereby conferring universal pH-sensitive binding properties to the antibodies. The invention also relates to methods of isolating and generating said antigen binding proteins, compositions and medical uses thereof.

The invention provides an SNP (Single Nucleotide Polymorphism) site related to turbot non-ocular side blackening, a primer pair and application, and belongs to the technical field of molecular markers. Wherein an SNP (Single Nucleotide Polymorphism) site related to turbot blackening is positioned at the 277th site of a coding region of the gene notumpectinacetylesterase 2, the basic group of the SNP site is mutated into C from T, and the amino acid is mutated into histidine from tyrosine; one SNP site related to turbot blackening is located at the 1154th site of a coding region of a gene KIT progene-oncogene, and the other SNP site related to turbot blackening is located at the 1154th site of a coding region of a gene KIT progene-oncogene receptor kinase b, the basic group of the SNP site is mutated from A to G, and the amino acid of the SNP site is mutated from aspartic acid to glycine. Researches show that genotype distribution of the SNP site between normal turbots and blackened turbots has significant difference.

The invention discloses application of copper-amino acid nano enzyme in preparation of anti-inflammatory drugs, and relates to the technical field of biomedical new materials, amino acids comprise glycine, arginine, histidine, threonine, phenylalanine and cysteine; the ratio of the amino acid to the copper ions is 1: (0.5-5), and the synthesis temperature of the copper-cysteine nano enzyme is 25-125 DEG C. The copper-amino acid nano-enzyme library established by the invention has efficient hydroxyl free radical, superoxide free radical and hydrogen peroxide scavenging activity; wherein the copper-cysteine nano-enzyme shows the highest enzymatic activity, and shows low toxicity and good biocompatibility in both the cell level and the animal level; meanwhile, the copper-cysteine nano-enzyme also shows anti-inflammatory activity and anti-oxidative stress activity, can remarkably improve cell inflammation and body inflammation, relieves and treats dextran sodium sulfate induced mouse ulcerative colitis, and can be further applied to preparation of drugs for treating inflammatory bowel diseases.

Formulations for antibodies and / or antigen-binding molecules (ABMs) that bind to Porphyromonas gingivalis are described. The formulations may be used in treating infections involving P. gingivalis, such as periodontal disease. The formulations comprise at least one of histidine, saline, acetic acid, citrate phosphate, sucrose, and / or Poloxamer P188. In some embodiments, the formulations may also be pH adjusted.

The present invention relates to a recombinant human elastin protein, and its preparation method and application. The recombinant human elastin protein comprises one or more elastin domains in the amino acid sequence of the full-length human elastin protein as shown in SEQ ID NO.1, as well as one or more of a secretion tag, a histidine tag, a fluorescent protein, and a protease cleavage site. The amino acid sequence of the recombinant human elastin protein is shown in SEQ ID NO.2. The nucleotide sequence is a recombinant plasmid, a recombinant vector, or a recombinant bacterium. The preparation method comprises: synthesizing the nucleotide sequence as shown in SEQ ID NO.1, constructing a recombinant protein, inducing expression, centrifuging, purifying, and drying to obtain the recombinant human elastin protein as shown in SEQ ID NO.2. The application is to detect and evaluate the anti-aging, anti-wrinkle, and firming effects of the recombinant human elastin protein, as well as in cosmetics. The preparation method of the present invention is simple, the protein expression level is high, and the cosmetic product has anti-aging, anti-wrinkle, and firming effects.

The invention provides an environment-friendly chalcopyrite inhibitor and a copper-molybdenum separation method, and belongs to the technical field of copper-molybdenum separation. The environment-friendly chalcopyrite inhibitor is a sulfur-containing histidine derivative, a unique aromatic conjugated structure of the environment-friendly chalcopyrite inhibitor can be converted into sulfydryl through thiocarbonyl tautomerization, S in the sulfydryl and N atoms which contain lone pair electrons and do not participate in conjugation in an aromatic ring cooperate with each other, copper ions in chalcopyrite can be directionally chelated, a formed chelate is of an annular structure, and the chalcopyrite inhibitor can be used for inhibiting copper ions in chalcopyrite. Chelation with molybdenum in molybdenite is avoided, and excellent selectivity is shown. The environment-friendly chalcopyrite inhibitor contains carboxyl and tertiary amino at the same time, and it is guaranteed that the environment-friendly chalcopyrite inhibitor can efficiently inhibit target minerals in a wide pH window through the two hydrophilic functional groups of different structures. Based on the specific space structure of the environment-friendly chalcopyrite inhibitor, the types of functional groups and mutual cooperation of different functional groups, efficient selective inhibition of chalcopyrite in copper and molybdenum associated ores can be achieved safely and environmentally in a wide pH range.