47 results about "Trypsin activity" patented technology

The invention provides egg white powder with high foamability and a preparation method thereof and relates to reconstruction of whey protein structure and functional properties, belonging to the technical field of biological processing of foodstuffs. According to the invention, on the basis of preliminary work, enzymatic hydrolysis of lipase in advance and cooperative enzymatic hydrolysis of composite protease are utilized for treatment of egg white; total usage amount of lipase and composite protease is less than usage amount of individually used lipase or protease, and however, foamability and foam stability of egg white powder obtained by combined utilization of lipase and composite protease are higher than those of egg white powder obtained by individual utilization of lipase or composite protease; the egg white powder obtained in the invention can meet demands for high-grade products on the market, and the advantages of a simple process and high cost performance are achieved in the invention. According to the invention, the ratio of active usage amount of Aspergillus oryzae protease, papain and trypsin is determined to be 1:1:1; the usage amount and other technological parameters cooperatively allow egg white powder with high foamability to be obtained; egg white powder with high foamability provided in the invention enables the additional output value of eggs to be increased, lays a technical foundation for development and industrial production of special-purpose egg white powder products and increases economic benefits for enterprises.

The invention discloses a method for improving trypsin activity through an artificially-designed self-activated leading peptide sequence and belongs to the field of genetic engineering. Trypsin of an artificial self-activated leading peptide sequence TPAPPSDDLGTFDDDDK is fused at an expression N end of a pichia pastoris engineered strain constructed by the method. Trypsin activity (trypsin amidase activity) of the yeast engineered strain GS115-Sedeif reaches 156U.mL-1, and esterase activity is 15015.8U.mL-1 (BAEE serving as a substrate), which are 1.82 times and 3.29 times of strain trypsin activity before modification. By the method, the key problem of low trypsin heterogeneous expression is solved. By applying the recombinant strain to produce trypsin, the method has the advantages of high yield, simplified fermentation process and convenience in industrial application.

The invention discloses a device for simulation of digestion in small intestine and a use method thereof. The device comprises a small intestine reactor, a stirrer, a water-bath control device, a computer monitoring system and a small intestine evacuation pump. A small intestinal fluid is added into the small intestine reactor, a solution or a dispersion liquid to be detected is added into the small intestine reactor, a simulator simulates small intestine peristalsis, the water-bath control device controls a temperature in the small intestine reactor, the computer monitoring system monitors an internal temperature, a pH value and digestion time of the small intestine reactor, the small intestine evacuation pump simulates small intestine evacuation, the digested product is collected, pancreatin and trypsin activity is eliminated, the digestion simulation process is repeated three times, and a digestion case of the material to be detected is detected. The device realizes first simulation of specific and detailed digestion in small intestine, realizes observation of digestion of various active materials or nutrients in the human small intestine, carries out simulation in a simulation environment designed according to a human physiological environment, has high conformity to the small intestine digestion and has high accuracy in simulation environment control.

The invention relates to a method to make trypsin activity restraining peptide by compound enzyme multiple step directional enzymolyzing oysters. The feather is that: adding oyster meat into 2-4 times weight Tris-Hcl buffer solution and pulping; according to 550-650U/g meat ratio to add flavor alkali protease, whisking in constant temperature and enzymolyzing for 1-2 hours under the temperature between 45-55 degree centigrade, then putting out enzyme, and cooling; using Hcl to adjust the PH value to 5-6, adding bromelain according to 650-750U/g meat ratio, whisking, enzymolyzing for 1-2 hours under 45-55 degree centigrade, then putting out enzyme, cooing, centrifuging, gathering the supernatant filtering, separating and purifying, then freezing out. The product has high activity and the restrain rate to the activity of commodity trypsin could reach 67%.

The invention discloses a serum-free medium for stem cells. The serum-free medium can be used for culturing mesenchymal stem cells. The serum-free medium for stem cells comprises DMEM/F12, cell growthfactors, hormones, proteins, vitamins and reducing substances, adherence promoting substances, trypsin inhibitors and other components. The serum-free medium of the invention is definite in added components, stable and controllable quality and batch consistency, and high safety and stability. The stem cell medium can inhibit trypsin activity, promote cell adherence and maintain the characteristics and proliferation ability of mesenchymal stem cell for a long time, and is applicable as an alternative to a serum medium.

The instant invention provides a method of treating an animal suffering a disease characterized by excessive apoptosis by administering a therapeutically effective amount of at least one serine protease inhibitor and thereafter monitoring a decrease in apoptosis. The inhibitor of the invention includes α₁-antitrypsin or an α₁-antitrypsin-like agent, including, but not limited to oxidation-resistant variants of α₁-antitrypsin, and peptoids with antitrypsin activity. The diseases treatable by the invention include cancer, autoimmune disease, sepsis neurodegenerative disease, myocardial infarction, stroke, ischemia-reperfusion injury, toxin induced liver injury and AIDS. The method of the invention is also suitable for the prevention or amelioration of diseases characterized by excessive apoptosis.

The invention aims to provide a proteomics analysis method based on SP3 enzymolysis. The method comprises the following steps: adding lysate into cells of a sample to be detected for denaturation; wherein the component of the lysis solution is 50mM of 4-hydroxyethylpiperazine ethanesulfonic acid; 1% lauryl sodium sulfate, 1% of polyethylene glycol octyl phenyl ether; 1% Tween 20, 1% of ethyl phenyl polyethylene glycol; 5 mM of ethylenediamine tetraacetic acid; 50mM sodium chloride, 1% of glycerol; a 1 * protease inhibitor; and 5 mM dithiothreitol, adding a magnetic bead replacement lysate intothe denatured sample; removing a denaturant influencing trypsin activity; after the replacement is finished, carrying out lysine protease enzymolysis and trypsin enzymolysis on the denatured sample;the method has the advantages that automation can be achieved, the repeatability of experiments of different batches is improved, and meanwhile the flux is improved, and meanwhile the method is not inferior to a traditional protein enzymolysis method in terms of evaluation indexes such as the peptide fragment recovery rate and the sample repeatability.

The invention relates to graphene oxide modified by polyethylene glycol. The graphene oxide can be used as trypsin activator. The graphene oxide modified by the polyethylene glycol comprises graphene oxide and polyethylene glycol; one end of the polyethylene glycol is an amino group, and other end of the polyethylene glycol is an imino group, and nitrogen atoms of the imino group and carbon atomsin carbonyl of the graphene oxide are connected with each other to form an amido bond; the height of the graphene oxide is 1 to 2nm, and the size of the graphene oxide is 10 to 30nm; the polyethyleneglycol is a liner-chain polyethylene glycol of which the molecular weight is 1,800 to 2,200; and the graphene oxide comprises 25 to 35 weight percent of the polyethylene glycol. The graphene oxide modified by the polyethylene glycol is easy to synthesize, and can specifically improve the activity and the thermal stability of trypsin; and the activity and stability of the trypsin are improved to meet biomedical demand of the trypsin.

The invention provides a group of trypsin resistant antimicrobial peptides and a preparation method thereof. Six trypsin active sites in a NZ2114 sequence are subjected to selective mutation with a protein directional transformation technology. Trypsin resistant mutants with amino acid sequences shown in SEQ ID NO:1-SEQ ID NO:33 are designed, and recombinant expression of the trypsin resistant mutants in pichia pastoris is realized. NZ2114 trypsin resistant derivatives are designed for the first time, and measurement shows that the trypsin degradation rate of part of the mutants (particularly double mutants and all triple mutants) is increased remarkably by 16.67%-25%. The trypsin resistant antimicrobial peptides show significant antibacterial activity against staphylococcus aureus ATCC25923, ATCC43300 and ATCC6538, and MIC (minimal inhibitory concentration) is 0.25-16 mu g/ml. The trypsin resistant antimicrobial peptides obtained with the method can be applied to fields such as antimicrobial drugs, food additives, cosmetics and feed additives and other fields, and have a broad application value and market prospect.

The invention discloses a bait feeding method for improving survival rate of loach fries, which includes the following steps: (1) feeding a primary bait; (2) feeding a live bait instead of the primarybait step by step; and (3) feeding an artificial compound feed instead of the live bait. The bait feeding method for loach fries greatly improves the survival rate and growth rate of loach fries. Thesurvival rate of feeding rotifers reaches more than 70% in a primary feeding period of loach larvae; amylase activity of loach larvae is increased significantly after fairy shrimps are fed instead ofthe rotifers; and the trypsin activity of young loaches is increased significantly after the artificial compound feed is fed instead of the fairy shrimps, with the survival rate reaching more than 60%. According to the method, the growth and weight gain are rapid, and economic benefits are higher.

The purpose of the present invention is to acquire a highly proliferative cell at a high efficiency from a sample derived from a biological tissue. Provided is a composition for dispersing a biological tissue, wherein a solution formulation of the composition has a collagenase activity of 0.30-10 U/mL, said collagenase activity being determined by a method for measuring FALGPA-decomposing activity, and a trypsin activity of 0-30 U/mL at a formulation concentration of the composition, said trypsin activity being determined by a method for measuring BAEE hydrolytic activity.

The invention discloses a method for detecting the activity of residual trypsin in a cell product. The method is characterized in that trypsin is used to catalyze hydrolysis of N-benzoyl-L-arginine ethyl ester hydrochloride into N-benzoyl-L-arginine hydrochloride and ethanol, and detecting the absorbance of the hydrolyzed reaction system at a wavelength of 253 nm in order to determine the activity of trypsin. The new trypsin activity detection method is obtained when the optimum reaction temperature is 37 DEG C and the optimum detection time is 25 min after the reaction starts; and the method has high sensitivity, so the method can be used to detect the activity of the residual trypsin in the cell product. The method for detecting the activity of residual trypsin in the cell product is simple, sensitive and practical.

The invention discloses the application of mogroside IIE in preparing trypsin inhibitors, and belongs to the technical field of medicines. After a long period of extensive trials, the inventor of thepresent application finds that the mogroside IIE can inhibit the activity of trypsin at the acinar cell background, and the inhibition has dependence on time and concentration. In addition, the mogroside IE can inhibit the activation of trypsinogen by an acute pancreatitis inducer-cerulein. At the same time, that the mogroside IE inhibits the activation of the trypsinogen is related to cathepsin B, so that the mogroside IE can be used to prepare trypsin inhibitors.

The invention belongs to the field of biological, and particularly relates to a method for detecting trypsinase activity. A simple and convenient method for detecting the trypsinase activity is builtby using the mutual action differences of polypeptides before and after the trypsinase enzyme digestion and graphene oxide loaded with electrochemical active molecule thionine. The graphene oxide haslarger specific surface area, and can load a great amount of thionine; the effects of amplifying electrochemical signals and improving the detection sensitivity are achieved. The gold electrode surface is modified by gold sulfhydryl bond covalent formed by gold and sulfhydryl of tail end cysteine via substrate polypeptides; the sulfhydryl-containing polypeptides are subjected to covalent modification onto the gold surface; then, 6-mercapto-l-hexanol is used for space occupation; non-specific adsorption polypeptides are removed; the electrode surface blank position is sealed; the N tail end ofthe substrate polypeptide sequence is provided with histidine; the histidine has positive charges; graphene oxide containing rich carboxyls have negative charges after dissociation; stronger static electricity mutual action exists between the histidine and the graphene oxide, so that a prepared compound is adsorbed to the final modified electrode product.

The invention relates to a supermolecular assembly for trypsin based on label-free fluorescence detection and a preparation method of the supermolecular assembly and belongs to the technical field of interdisciplinary science of materials, biology and analytical chemistry. The supermolecular assembly is characterized by being compound aqueous solution formed by a quaternary ammonium cationic gemini surfactant and heparin sodium under the electrostatic action. The preparation method comprises the following steps: firstly determining critical micelle concentration of the gemini surfactant, forming the supermolecular assembly by the gemini surfactant and the heparin sodium at the concentration, and enabling a hydrophobic dye Nile red to enter the inner cavity of the assembly, so that fluorescence emission is enhanced; then adding protamine which has specific interaction with the heparin sodium, and disassembling, so that the fluorescence emission intensity is reduced with increase of the concentration of the protamine; and then adding trypsin to hydrolyze the protamine and restore the assembly, so that the fluorescence emission intensity is increased with increase of trypsin concentration, and trypsin activity detection is realized. The supermolecular assembly provided by the invention is simple to prepare and low in cost and has good salt resistance and a broad application prospect.

The invention relates to an amidino guanido substituted aromatic heterocyclic compound represented by the general formula (I), wherein, R1, R2 may represent the same or different groups, and may be substituted at any position of the hetero-aromatic ring, and may be represented as: -O-R3, -S-R3, -COOR3, -COR3, -O-COR3, -NH-COR3 and groups shown in the description, m represents a natural number such as 0, 1 or 2; R3 represents a hydrogen atom, linear alkyl or branched alkyl, substituted or non-substituted aromatic group or aromatic heterocyclic ring; R4 and R5 represent a hydrogen atom, linear alkyl or branched alkyl, aromatic group or aromatic heterocyclic ring; A ring represent a cycloaliphatic ring, aromatic ring, aromatic heterocyclic ring or fused heterocycle; X and Y represent carbon, nitrogen, oxygen, sulfur and the like and can be any position on the ring; B represents -COO-, -CONH-, -OCO-, -NHCO- or the like, and n represents a natural number such as 0, 1 or 2. The compound disclosed in the invention has stable property, can inhibit tryptic activity proved by pharmacology experiments, and can be used for preparing medicines for treating acute or chronic pancreatitis.

The invention discloses a spleen-strengthening syrup processing and spleen-hydrolyzing process for children, which comprises the following steps: taking 250-350kg of fresh minced pig spleen, accurately weighing the fresh mince pig spleen according to the specification, conducting weighing for each barrel, adding water with the amount being 3-6 times by weight, uniformly conducting stirring, sucking a formed solution into a reaction tank in vacuum, introducing steam into an interlayer for heating under the steam pressure of 0.2-0.5 MPa, conducting stirring, adding a sodium hydroxide solution with the mass concentration of 4% to adjust the pH value to 7.2-7.5, keeping the temperature in the tank at 45-55 DEG C, adding 5-10kg of pancreatin (trypsin activity is higher than 2500 units), conducting hydrolyzing for 6-12 hours, adding phosphoric acid to adjust the pH value to 5.5-6.0, introducing steam into an interlayer for heating under the steam pressure of about 0.2-0.4 MPa, reducing the steam pressure to about 0.1 MPa after boiling, and keeping slight boiling for 30-50 minutes. The process is simple in operation steps, cost is low, and consumed time is short.

An object of the present invention is to provide a method for measuring tryptase activity in a blood sample accurately and rapidly by a convenient operation in order to accurately evaluate the state of a disease whose state involves mast cells. The present invention enables tryptase activity in a blood sample to be directly measured without the pretreatment, such as purification or concentration, of the blood sample, using a substrate for measuring tryptase activity, comprising a tripeptide C-terminally linked through a peptide bond to a dye label, selected from the following formulas (1) to (3): (1) Lys-Ala-Arg-X, (2) Ala-Ala-Arg-X, and (3) Abu-Ala-Arg-X (wherein X represents a dye label whose fluorescence characteristics or color development characteristics change upon the cleavage of the peptide bond with Arg, and Abu represents 2-aminobutyric acid).