327 results about "Solid-phase synthesis" patented technology

The invention discloses a scorpion anti-inflammatory polypeptide as well as a screening method and application thereof, and belongs to the technical field of traditional Chinese medicinal material polypeptides. The scorpion anti-inflammatory polypeptide is one of G4, G5 and G17. The method comprises the following steps: detecting a scorpion buthus martensii polypeptide extract through nanoElute 2 nanoliter liquid phase separation, timsTOFPro2 mass spectrometry and BPS Novor search analysis, screening a scorpion buthus martensii polypeptide, and further synthesizing the screened candidate polypeptide by adopting a solid-phase synthesis method; the effect of the synthesized candidate polypeptide on inhibiting microglial cell inflammation is evaluated through a qPCR method, and then the scorpion buthus martensii anti-inflammatory polypeptide is screened out. The Buthus martensii Karsch anti-inflammatory polypeptides G4, G5 and G17 screened by the method, especially G5, can significantly inhibit microglial cell inflammation and present concentration dependence, a theoretical basis is provided for medicinal development of Buthus martensii Karsch polypeptides, and a potential anti-neuroinflammation mechanism of the Buthus martensii Karsch polypeptides is disclosed.

The invention provides an enzymolysis preparation method of a milk-derived taste enhancing peptide, which comprises the following steps: carrying out enzymolysis on a liquid dairy product by using flavourzyme and glutaminase, and then carrying out enzyme deactivation to obtain an enzyme-deactivated product; carrying out acidification centrifugation and ultrafiltration on the enzyme-deactivated product, and freeze-drying the separated effluent to obtain freeze-dried powder; and loading the freeze-dried powder, and separating by a glucose gel column. The product disclosed by the invention does not generate bitter taste, and compared with a sample which is not subjected to enzymolysis, the flavor level of an original skimmed milk product is enriched, and the sample subjected to enzymolysis has the mellow taste of caramel and frankincense. The method comprises the following steps: separating milk-derived taste active peptides from milk-derived taste active peptides, predicting delicate flavor, anti-oxidation and anti-inflammatory activity and ACE blood pressure lowering functional activity of separated peptide liquid through a model, performing taste verification on the peptides predicted to have taste activity through Fmoc solid-phase synthesis, and performing sensory verification on the milk-derived taste active peptides LSFD, EDIKQME, IKQMEAE and TEDELQDK after synthesis, so that the milk-derived taste active peptides are obtained for the first time and are subjected to sensory verification.

The invention discloses a hexapeptide TE6 with xanthine oxidase inhibitory activity and a preparation method and application thereof, and belongs to the technical field of small molecule peptides. The amino acid sequence of the hexapeptide TE6 is TIATVE, and the hexapeptide TE6 can be prepared through a solid-phase synthesis method and an enzymolysis method. The hexapeptide TE6 is identified from a solieria cavaleriei proteolysis solution and has potential interaction with xanthine oxidase, under the concentration of 0.1 mg / mL, the xanthine oxidase inhibition rate is 44.74%, and compared with goose carnosine (the xanthine oxidase inhibition rate is 36.03%), the xanthine oxidase inhibition rate is remarkably increased (plt; 0.05), which is stronger in xanthine oxidase inhibitory activity, and can be used for preparing a preparation for inhibiting xanthine oxidase activity and relieving hyperuricemia.

The invention relates to a molecular tag DMDPM compound, a preparation method thereof and application of the molecular tag DMDPM compound in assisting homogeneous synthesis of heptapeptide H6K, and belongs to the technical field of organic synthesis. The molecular tag DMDPM compound is 2, 4-dimethoxy-4 '-diphenylphosphinyl oxydiphenyl alcohol, and the molecular tag DMDPM compound is 2, 4-dimethoxy-4'-diphenylphosphinyl The method has the advantages of a liquid-phase synthesis method and a solid-phase synthesis method, H6K can be simply, quickly, economically and efficiently synthesized and prepared, and a 2, 4-dimethoxy-4 '-diphenylphosphinyloxy diphenyl alcohol small-molecule auxiliary group (also called as a carrier) can be recycled and directly reused, so that raw material waste is reduced, waste pollution is reduced, the cost is saved, and environmental protection is facilitated.

The invention relates to the technical field of dielectric ceramic powder preparation processes, in particular to a multilayer ceramic capacitor, high-activity nano barium titanate powder for the multilayer ceramic capacitor and a preparation method of the high-activity nano barium titanate powder, and the method comprises the following steps: (1) reacting soluble barium salt with a precipitator to obtain barium carbonate precursor particles with high specific surface area; (2) uniformly coating the surfaces of the barium carbonate precursor particles with nano titanium dioxide particles by using a supercritical fluid flash evaporation technology to form a composite precursor; and (3) carrying out solid-phase synthesis reaction on the composite precursor, and sintering to obtain the nano barium titanate powder. Through the synergistic effect of two means of high-activity precursor preparation and nanoscale uniform coating, the composite precursor with extremely high specific surface area, surface energy and microcosmic uniformity is prepared, the thermal sintering temperature is effectively reduced, abnormal growth of crystal grains and lattice distortion are restrained, and the preparation method has the advantages that the preparation process is simple, and the preparation cost is low. The tetragonality of the nano barium titanate powder is obviously improved.

The present application relates to the technical field of dielectric ceramic powder preparation, and particularly relates to a multilayer ceramic capacitor, a high-activity nano-barium titanate powder for the multilayer ceramic capacitor and a preparation method of the high-activity nano-barium titanate powder, the method comprising the following steps: (1) reacting a soluble barium salt with a precipitator to obtain barium carbonate precursor particles with high specific surface area; (2) uniformly coating nano-titanium dioxide particles on the surface of the barium carbonate precursor particles by using a supercritical fluid flash technology to form a composite precursor; and (3) performing a solid-phase synthesis reaction on the composite precursor and sintering to obtain nano-barium titanate powder. The present application, through the synergistic effect of the two means of "high-activity precursor preparation" and "nano-level uniform coating", prepares a composite precursor with extremely high specific surface area, surface energy and micro-uniformity, effectively reduces the heat sintering temperature, suppresses abnormal grain growth and lattice distortion, and significantly improves the tetragonality of the nano-barium titanate powder.

The invention discloses an agaric polypeptide VR5 with alpha-glucosidase inhibitory activity and a preparation method and application thereof, and belongs to the technical field of small molecule peptides. The amino acid sequence of the auricularia auricula polypeptide VR5 is VGMLR, and the auricularia auricula polypeptide VR5 can be prepared by a solid-phase synthesis method and an enzymolysis method (flavourzyme). The agaric polypeptide VR5 has the beneficial effects that experiments prove that the agaric polypeptide VR5 has very high alpha-glucosidase inhibitory activity, IC50 is equal to 34.96 mu g / mL, the agaric polypeptide VR5 can be used as an alpha-glucosidase inhibitor for preventing or treating alpha-glucosidase mediated diseases, and the agaric polypeptide VR5 can be used for preventing or treating alpha-glucosidase mediated diseases. Or as a hypoglycemic active component, the composition is added into auxiliary hypoglycemic functional food for auxiliary regulation of the blood sugar level of hyperglycemia people.

The invention relates to a method for semi-solid-phase synthesis of a polycyclic compound and an intermediate, a long chain is synthesized through solid phase, then two-step ring closing is performed to form a key intermediate, and simple derivation is performed on the basis of the key intermediate to obtain a PCSK9 antagonist compound. According to the invention, starting materials for solid-phase synthesis are selected, steric hindrance is effectively avoided, and solid-phase reaction and subsequent liquid-phase correlation cyclization can be smoothly carried out, so that the yield is improved, and the cost is reduced.

The invention discloses an oligonucleotide synthesis process of a sulfo-PMO structure. In the oligonucleotide synthesis process of the sulfo-PMO structure, the molecular structural formula of sulfo-PMO is shown in the specification. According to the invention, the molecular structure of thio-PMO is specifically limited, and the synthesis of nucleotide phosphate amide and (thio) phosphoric acid amide in the solid-phase synthesis oligonucleotide is carried out along the direction from 5'to 3 ', that is, in each cycle period, the O5'or O6' position of the nucleotide phosphate amide and (thio) phosphoric acid amide monomer is firstly subjected to coupling reaction, and then the protecting group is removed at the O3 'or N3' position, so that the oligonucleotide phosphate amide and (thio) phosphoric acid amide are obtained. And releasing active hydroxyl or amino / amido to enter the next cycle. The protecting group adopted by the sulfo-PMO molecule is consistent with the protecting groups of other nucleotides, so that the conversion rate of each step of coupling reaction can be conveniently detected on line.

The invention discloses a long-afterglow self-luminous material based on multi-element rare earth synergistic sensitization and a preparation method thereof. SrAlO is used as a matrix, trap level distribution is optimized through ternary rare earth synergistic doping according to the molar ratio of Eu to Dy to Nd being 1: (0.4-0.6): (0.2-0.4), and a ZnO nanorod array is grown on the surface of a light-emitting core in an in-situ epitaxial mode to improve the light extraction efficiency; and a hydrophobic modified SiO core-shell coating layer with an ordered mesoporous channel is combined, and oxygen diffusion is promoted by utilizing a nanopore channel so as to accelerate trap regeneration and synchronously inhibit non-radiative recombination. The afterglow time of the material is not less than 8 hours, and the afterglow retention rate after aging at 60 DEG C is not less than 80%. A solid-phase synthesis process and red mud / fly ash industrial solid waste raw materials are adopted, and the carbon emission intensity is smaller than or equal to 6 kgCO / kg. The material can be widely applied to the fields of green traffic infrastructures such as expressways and tunnels.

The application relates to a synthesis method of an anti-freezing glycopeptide polypeptide and belongs to the technical field of polypeptide drug synthesis. The method comprises the following steps: 2-CL-Resin is used as a carrier resin, under the condition of adding an activating agent, the carrier resin and alanine are coupled to obtain Fmoc-Ala-2-CL-Resin; according to the amino acid sequence of the anti-freezing glycopeptide, other amino acids are sequentially coupled through a solid-phase synthesis method; after a protecting group is removed and the carrier resin is cleaved, the anti-freezing glycopeptide crude peptide is obtained; and after purification, salt conversion and freeze-drying, the anti-freezing glycopeptide polypeptide is obtained. The method has the advantages of short synthesis period, low cost, easy post-treatment, few by-products, high product yield, facilitation of large-scale production of the anti-freezing glycopeptide, and considerable economic applicative value and wide application prospect.

The invention provides a dipeptide capable of rapidly supplementing methionine and application thereof, and belongs to the field of nutritional and functional food. The problems of quickly supplementing methionine and promoting lactation are solved. The preparation method comprises the step of preparing the dipeptide GM of which the C terminal is methionine through solid-phase synthesis. The dipeptide GM can be used for supplementing methionine, and it is verified that compared with EM, KM and MM, the dipeptide GM has the higher methionine absorption rate in cells based on the PepT1 vector. The dipeptide GM can also be used for promoting lactation, and it is verified that the dipeptide GM has a better lactation promoting effect compared with EM, KM and MM.

The invention relates to the field of biological medicine, and discloses a pTH long-acting polypeptide compound as well as preparation and application thereof. According to the polypeptide, at least one amino acid residue of the 13th, 26th and 27th amino acid residues of a pTH (1-34) parent peptide sequence is connected with octadecanedioic acid or eicosanoic acid and a derivative modification group of octadecanedioic acid or eicosanoic acid, and the polypeptide is covalently combined with a polypeptide skeleton through an AEA-AEA-gamma-Glu connecting unit. The binding capacity of the polypeptide and serum albumin is remarkably enhanced by utilizing a fatty acid side chain modification means, and meanwhile, the half-life period is prolonged. The pTH long-acting polypeptide compound disclosed by the invention has remarkable osteogenic activity promoting effect, can promote proliferation of MC3T3-E1 cells and generate osteogenic markers and calcium nodules under osteogenic induction conditions, and the binding capacity of the pTH long-acting polypeptide compound and serum albumin is improved by 2-6 times. The invention further provides a solid-phase synthesis method of the polypeptide compound and a pharmaceutical composition containing the polypeptide compound, the polypeptide compound can be used for treating osteoporosis and parathyroid hypofunction, and the compliance problem that an existing medicine needs to be injected every day is effectively solved.

The invention discloses a low-temperature solid-phase synthesis cobalt blue pigment preparation method, which comprises: (1) placing a cobalt source, an aluminum source and an inert template dispersant in a planetary ball mill, carrying out ball milling, and drying to obtain nanometer composite precursor powder; (2) adding a mixture of a lithium source and a boron source into the nano composite precursor obtained in the step (1), putting the mixture into a mortar, and mechanically mixing to obtain a mixed material; and (3) putting the mixed material obtained in the step (2) into a muffle furnace, melting and calcining, cooling to room temperature along with the furnace, grinding, washing with hot water, and drying to obtain cobalt blue pigment powder. According to the method, the synthesis temperature is low, particle coarsening and sintering caused by high temperature are avoided, the energy consumption is low, the process is green, and the obtained cobalt blue pigment is pure in chromaticity, large in specific surface area and excellent in thermal stability.

The application provides a mung bean protein salty taste enhancing peptide, a screening and preparation method and application. The method comprises the following steps: step 1, carrying out step-by-step enzymolysis on mung bean protein by using alkaline protease and flavor protease, carrying out ultrafiltration grading, and screening an initial extract of the salty taste enhancing peptide by using an electronic tongue; step 2, further identifying polypeptide sequences by using LC-MS / MS; and step 3, screening polypeptides with strong interaction capability with salty taste receptors TMC4 and ENaC by combining biological activity prediction, target active fragment screening, safety and physicochemical property evaluation and molecular docking analysis. The salty taste enhancing peptide of the mung bean protein obtained by screening comprises polypeptides represented by RPFF, APDLRGY, WDDIGGL, FDGF and AEFF, and contains RP, RG, DD, DGF and FF characteristic peptide segments, respectively. The polypeptides are synthesized by using a solid phase, and the salty taste enhancing effect of the polypeptides is verified by using an electronic tongue. When 0.03% of the above synthesized polypeptides are added to a 0.4% NaCl solution, the salty taste enhancing rates are 90%, 62%, 34%, 52% and 42%, respectively. The polypeptides can significantly enhance salty taste perception of a solution under low-salt conditions, and achieve the effect of salt reduction without taste reduction.

The invention discloses uric acid-reducing peptide goat milk powder and a preparation method thereof, and belongs to the technical field of enzymes. According to the process for preparing the uric acid lowering peptide by hydrolyzing goat milk through the compound enzyme, the total addition amount of the compound enzyme (the enzyme activity ratio of neutral protease N to neutral protease X is 1: 1) is 4000 U / g-6000 U / g, enzymolysis is conducted for 2-3 h at the temperature of 45-55 DEG C, and under the condition, the xanthine oxidase inhibition rate is 71.67 + / -1.32%-83.64 + / -0.98%. The enzymolysis goat milk containing the uric acid-reducing peptide is subjected to spray drying to prepare the uric acid-reducing peptide goat milk powder, and the storage stability of the goat milk powder is relatively good. The amino acid sequence and the source of the uric acid lowering peptide are separated and identified, the in-vitro uric acid lowering activity of the uric acid lowering peptide is verified through the solid-phase synthesized uric acid lowering peptide, and a theoretical basis and technical support are provided for development of new uric acid lowering peptide goat milk products.

The invention relates to the technical field of biological medicines, and particularly discloses synthesis and application of oligonucleotide with a spacer group embedded between 5-terminal oxygen and thiophosphoric acid. The chemical modification strategy comprises the following steps: preparing a modified nucleotide phosphoramidite monomer in which a spacer group is embedded between O5'and thiophosphoric acid P (V); performing solid-phase synthesis on the modified nucleotide phosphoramidite monomer to construct a target oligonucleotide molecule; a spacer group is embedded between oxygen at the 5 '-terminal of the oligonucleotide and thiophosphoric acid P (V) to form a 5'-terminal thiophosphoric acid structure; as the terminal modified thiophosphoric acid belongs to a non-phosphatase substrate, the terminal modified thiophosphoric acid can resist exonuclease degradation and improve the biological activity of siRNA after being modified.

The invention discloses nanoscale Ti2O3, a preparation method and application of the nanoscale Ti2O3 as a catalyst carrier, and belongs to the technical field of nano material preparation. According to the invention, a solid-phase synthesis method is utilized, nano titanium powder and nano titanium dioxide are used as raw materials, and the nano-scale Ti2O3 brownish black powder with uniform particle size distribution is controllably synthesized. Meanwhile, a series of noble metal supported catalysts are synthesized by taking the catalyst as a catalyst carrier. According to the invention, rapid synthesis of nanoscale Ti2O3 is realized, and the particle size of the prepared sample is uniform and is about 300nm. The preparation method has the characteristics of high efficiency, rapidness, low equipment requirement, simplicity, easiness in repetition, high product purity and capability of realizing large-scale synthesis. Meanwhile, the prepared nanoscale Ti2O3 is small in size and uniform, so that a catalyst prepared by taking the nanoscale Ti2O3 as a carrier has relatively good dispersity, shows excellent electrocatalytic activity, can be prepared into catalyst slurry with relatively high uniformity, and is suitable for the fields of electrochemical catalysis and energy conversion.

The invention discloses a hexapeptide LR6 with anti-inflammatory activity and a preparation method and application thereof, and belongs to the technical field of small molecule peptides. The amino acid sequence of the hexapeptide LR6 is LDAVDR, and the hexapeptide LR6 can be prepared through a solid-phase synthesis method and an enzymolysis method. The hexapeptide LR6 is identified from spirulina platensis proteolysis liquid and has potential interaction with Keap1, an LPS-induced RAW264.7 cell test shows that TNF-alpha, IL-1beta and IL-10 can be remarkably inhibited by treatment of low-dose (200mM) and high-dose (400mM) hexapeptide LR6, the inhibition effect of the high-dose hexapeptide LR6 is superior to that of positive control dexamethasone, and the inhibition effect of the high-dose hexapeptide LR6 is superior to that of positive control dexamethasone. Compared with dexamethasone, the hexapeptide LR6 has a better anti-inflammatory effect and can be used for preparing anti-inflammatory drugs.

To provide a method for producing a high-purity peptide compound in a high yield under a condensation condition applicable even to a highly rare non-natural amino acid by using an easily available condensing agent and additive capable of suppressing prematurecleavage and also suppressing a side reaction especially in a condensation reaction process of a solid phase synthesis method of a peptide.SOLUTION: Provided is a method for producing a peptide compound, including a step of condensing a first amino acid or peptide and a second amino acid or peptide in the presence of an additive and a condensing agent to obtain a condensate, wherein the number of moles of the additive is smaller than the number of moles of the second amino acid or peptide. By using a small amount of the additive with respect to the amino acid or peptide to be added to the N-terminus, the condensation reaction can be allowed to proceed efficiently even when an amino acid having large steric hindrance is contained, and the target peptide compound can be obtained with high yield and high purity.SELECTED DRAWING: None

The invention discloses a fully-protected polypeptide and a preparation method thereof, belongs to the technical field of polypeptide compound synthesis, and particularly relates to fully-protected peptide resin prepared through solid-phase synthesis. Carrying out cutting and unitary cyclization on the full-protection peptide resin to obtain unitary cyclic peptide; carrying out binary cyclization treatment on the unitary cyclic peptide to obtain a bicyclic peptide compound Cyclo (His-Cys-Lys-Gly-His-Cys-Lys-Gly-, and bridging a disulfide bond with Cysamp; the binary cyclization comprises cyclization under the action of iodo methanol and ascorbic acid; or the binary cyclization is cyclized in DMSO (Dimethylsulfoxide). The anti-aging and anti-oxidation bicyclic peptide compound prepared by the preparation method disclosed by the invention has the following beneficial effects of low toxicity, good stability, capability of improving I-type collagen expression, good anti-oxidation effect and good anti-inflammatory effect.

A preparation method for semaglutide. The method comprises: producing a semaglutide resin by means of a solid-phase synthesis, producing crude semaglutide by cleavage and deprotection, producing refined semaglutide by purification and freeze-drying, comprising the solid-phase synthesis of a semaglutide 1-6 peptide fragment resin, which is cleaved and purified to serve as a first peptide fragment; and synthesizing a lysine having a sidechain group at locus 20 of semaglutide to serve as a second peptide fragment. In the method, prepared is a semaglutide loci 1-6 fully protected peptide fragment, which serves as a key starting material applied in the solid-phase synthesis of semaglutide, thus reducing the generation of D-His, D-Glu, D-Thr, D-Phe racemic impurities and +Gly impurities, reducing the difficulty of coarse product purification, increasing the purity and yield of semaglutide, reducing synthesis costs, and favoring industrialized large-scale production.

The invention discloses a starch composite adhesive for synthesizing zinc acetylacetonate based on a self-polarized ceramic solid phase as well as a preparation method and application of the starch composite adhesive, and belongs to the technical field of wood adhesives. (1) solid-phase synthesis of zinc acetylacetonate; (2) preparation of starch grafted acrylamide; (3) cross-linking modification of starch grafted acrylamide; and (4) compounding phenolic resin. The preparation method comprises the following steps: initiating acrylamide to be grafted to starch by using ammonium persulfate, then adding zinc acetylacetonate which is synthesized based on a self-polarization ceramic reactor solid phase as a cross-linking agent to obtain cross-linked modified starch grafted acrylamide, and then compounding the cross-linked modified starch grafted acrylamide with water-soluble phenolic resin, thereby realizing the preparation of the high-strength, water-resistant, aging-resistant and environment-friendly adhesive. The adhesive can effectively solve the problem that the strength of a traditional starch adhesive is quickly attenuated in a humid environment, and is suitable for high-humidity application scenes such as ships and ocean platforms.

The present application relates to a method for synthesizing leu-enkephalin by Fmoc method, which uses Fmoc-protected amino acid as monomer, and sequentially connects amino acid to resin. In the synthesis of leu-enkephalin, all the amino acids do not have any side chain protection group. The Fmoc protection group is removed by using a solution of 1.00 mol / L imidazole and 0.02 mol / L tricyclohexylphosphine in tetrahydrofuran, and finally leu-enkephalin is obtained by removing the resin with aqueous trifluoroacetic acid. The present application first uses imidazole and tricyclohexylphosphine as components of Fmoc deprotection agent, instead of traditional pyridine. The deprotection agent is not controlled by "controlled chemicals", is cheap and easy to obtain, is stable in nature, and is low in toxicity, volatility and corrosion. The deprotection agent has excellent Fmoc removal ability, does not cause phenolic ring acylation side reaction of tyrosine side chain, does not need any side chain protection, simplifies the production process of polypeptide, reduces the preparation cost of polypeptide, and provides great improvement space for the design of synthesis strategy of polypeptide containing basic sensitive side chain protection group.

The present invention relates to a rubidium fluoro-scandium borate compound, a rubidium fluoro-scandium borate nonlinear optical crystal, and a preparation method and application thereof. The rubidium fluoro-scandium borate compound has a chemical formula Rb2ScB3O6F2, does not contain a symmetry center and has a molecular weight of 382.33 g / mol. The rubidium fluoro-scandium borate nonlinear optical crystal belongs to the monoclinic crystal system, and belongs to the non-centrosymmetric space group P21, and the unit cell parameters are: a=4.0372(10) Å, b=11.800(3) Å, c=8.823(2) Å, α=γ=90°, β=98.327(11)°, Z=2. The present invention adopts a high-temperature vacuum packaging method or a solid-state synthesis method to prepare rubidium fluoro-scandium borate compounds. The present invention adopts a fluxing agent method to prepare a rubidium fluoro-scandium borate nonlinear optical crystal, which have the advantages of short absorption cutoff edge, large nonlinear optical effect, good thermal stability, and stable physical and chemical properties. The rubidium fluoro-scandium borate nonlinear optical crystal of the present invention can be used to fabricate nonlinear optical devices, which have important applications in fields such as optics, military, laser lithography, and communication, etc.

This invention relates to the fields of molecular biology and biomedicine, disclosing plasma-active peptides with antithrombotic effects and their uses. The invention obtains various active peptides from plasma through screening and solid-phase synthesis, and confirms their biological activity through in vitro platelet aggregation experiments and in vivo arterial thrombosis model experiments. Results show that peptides 1957, 1960, and 1961 significantly inhibit collagen-induced platelet aggregation, exhibiting good antiplatelet activity; animal experiments show that peptides 1955, 1957, 1960, and 1961 significantly inhibit arterial thrombosis. These active peptides are derived from endogenous plasma components, belonging to natural antithrombotic substances, possessing good physiological compatibility and safety advantages, and reducing the risk of immunogenicity and adverse reactions. These peptides can exert antithrombotic effects without relying on traditional antiplatelet drugs, providing a new source of active molecules and treatment options for the prevention and treatment of thrombotic diseases.

The application discloses a tetrapeptide IR4 with uric acid reducing activity, and a preparation method and application thereof, and belongs to the technical field of small molecular peptides. The amino acid sequence of the tetrapeptide IR4 is IDWR, and the tetrapeptide IR4 can be prepared by a solid-phase synthesis method and an enzymatic hydrolysis method. The tetrapeptide IR4 is identified from a porphyra haitanensis protease hydrolysate, has potential interaction with xanthine oxidase, and can reduce the uric acid content of zebrafish by 33.6% (to 5.93+ / -0.47 mu mol / g protein) at a concentration of 100 mu g / mL. Compared with an anserine (which can reduce the uric acid content of zebrafish by 25.7%), the tetrapeptide IR4 has better uric acid reducing activity. Compared with allopurinol (which can reduce the uric acid content of zebrafish to 4.61+ / -1.11 mu mol / g protein), the uric acid reducing ability of the tetrapeptide IR4 and the allopurinol has no significant difference. The tetrapeptide IR4 can be used for preparing uric acid reducing drugs and relieving hyperuricemia.

The application relates to the field of polypeptide medicine preparation, and particularly discloses a preparation method of bumenol peptide, which adopts a solid-liquid combination mode, liquid-phase synthesis of a tripeptide fragment Fmoc-Lys(Ac-Nle-Asp)-OMe, subsequent solid-phase synthesis of a cyclic heptapeptide methyl ester, cleavage, cyclization, deprotection and hydrolysis to obtain crude bumenol peptide. The cyclization site is alpha-COOH of Trp and alpha-NH2 of Lys, the reaction yield is high, and the cyclization problem between Lys and Asp in most current patents is solved. The process operation is simple, the deprotection reagent is conducive to environmental protection requirements. The crude product is easy to purify, the finished product has high yield and purity, and is suitable for industrial large-scale production.

The invention provides a device for DNA solid-phase synthesis and a preparation method of the device. The device comprises a solid-phase synthesis carrier and a micropore array which is arranged on the solid-phase synthesis carrier and is provided with a wrinkled inner wall. The pore diameter of the micropores is 70-90 [mu] m, the pore depth is 5-6 [mu] m, the inner wall roughness is 0.5-5 [mu] m, the distribution density of the micropores on the surface of the solid-phase synthesis carrier is greater than 1111 / mm < 2 >, and the reaction contact surface provided by the solid-phase synthesis carrier is further expanded; meanwhile, hydrophilic treatment and synthesis starting point grafting are carried out on the inner walls of the micropores, hydrophobic membrane coating is carried out outside the micropores, the synthesis density is increased, and the error rate of the synthesis process is reduced. According to the solid-phase synthesis device, the reaction contact area is further enlarged while the synthesis accuracy is ensured, the coupling density is increased, and a high-yield synthesis device is provided for solid-phase synthesis of DNA by a phosphoramidite method.

The invention relates to ribozyme for labeling biotin on target RNA (Ribonucleic Acid) as well as a screening method and application thereof. The RNA labeling technology is one of core tools for modern molecular biology research and clinical diagnosis. A specific marker is covalently linked to a target RNA molecule, so that accurate tracking, efficient detection and functional analysis of RNA can be realized. A biotin-streptavidin system becomes one of the technical routes which are most widely applied due to extremely high affinity and signal amplification capability of the biotin-streptavidin system. At present, common biotin-labeled RNA technical methods mainly comprise a chemical solid-phase synthesis method, an enzymatic method and a chemical labeling method. However, the methods have the limitations of poor site specificity, low efficiency, complex manipulation and the like in the use process. The engineering ribozyme for catalyzing RNA biotinylation is obtained by taking 12: 0 biotin coenzyme A as a biotin donor through an in-vitro screening technology. The ribozyme provided by the invention can efficiently and specifically carry out biotin labeling on target RNA, the reaction process is simple, and the labeling activity is up to 90% or above.