12 results about "Heat inactivation" patented technology

The application belongs to the technical field of biology, and discloses a construction method of an algorithm model for predicting the heat inactivation efficiency of microorganisms in biohazard wastewater. By monitoring the temperature change of the sterilization medium, the model calculates the inactivation efficiency of the microorganisms in the water heat sterilization system in real time based on an integral algorithm. The method has the dual functions of process optimization and safety evaluation, can not only optimize the water heat sterilization process parameters, but also provide key environmental risk evaluation basis for the discharge of the live toxic wastewater after heat sterilization.

The invention provides a property-changed fructose-1, 6-diphosphate aldolase mutant and application thereof, and relates to the technical field of enzyme engineering. According to the invention, a series of enzyme mutants with enhanced structural stability are obtained by carrying out rational design and site-directed mutagenesis on key sites of wild fructose-1, 6-diphosphate aldolase. Compared with a wild type, the mutant can keep certain enzyme activity at high temperature, shows excellent heat resistance, can be used as a core biocatalyst to efficiently catalyze a chiral compound synthesis reaction taking dihydroxyacetone phosphate as a key precursor, can still keep high catalytic efficiency at 50 DEG C, and can be used for preparing a chiral compound. The key bottleneck that natural enzyme is prone to thermal inactivation in industrial application is solved, and the method has wide application prospects in green biological manufacturing of high-added-value products such as drug intermediates and rare sugar.

The invention provides a high temperature resistant feruloyl esterase and an application thereof. The feruloyl esterase wild type has a remarkable high-temperature-resistant characteristic and still shows relatively high thermal stability under the condition of 95 DEG C, and the thermal inactivation half-life period of the feruloyl esterase wild type can reach 5h. On the basis, after the feruloyl esterase mutant obtained through structural rationality modification continuously reacts for 5 h at the temperature of 75 DEG C, floccule precipitation is not observed, and stable catalytic activity is kept. In the application, the feruloyl esterase mutant disclosed by the invention and commercial xylanase have a synergistic effect, so that the release of bound ferulic acid in starch-removed wheat bran can be effectively promoted. The invention provides a novel enzymology tool for efficiently and quickly releasing the plant-derived ferulic acid under a high-temperature condition.

The present application belongs to the technical field of biological detection, and provides a kit for detecting cytokines in blood samples. The kit comprises fluorescent coded polystyrene magnetic microspheres coupled with capture antibodies, biotin-labeled paired detection antibodies, streptavidin-labeled phycoerythrin with a final concentration of 0.5-2 ug / mL, a washing buffer containing 0.05%-0.1% Tween-20 or triton-100, an experimental buffer containing 0.5%-2% bovine serum albumin, and a sample diluent. The sample diluent comprises the experimental buffer and treated human serum. The treated human serum is obtained by first heat inactivation and carbon adsorption treatment of human serum, and then centrifugal separation using an ultrafiltration centrifugal tube. By using the kit provided by the present application, quantitative results of 7 cytokines can be obtained in a single detection of a single sample, and the detection range can reach 0.977-128000 pg / mL.

The invention provides a property-changed dihydroxyacetone kinase mutant and application thereof, and relates to the technical field of enzyme engineering. Through rational design and molecular modification, wild dihydroxyacetone kinase is subjected to single-point mutation and combined mutation, a series of enzyme mutants with enhanced thermal stability are obtained, and the catalytic activity of the mutants under the high-temperature condition is remarkably superior to that of wild enzymes. The invention further provides a multienzyme coupling reaction system containing the dihydroxyacetone kinase mutant, and the multienzyme coupling reaction system is used for efficiently catalyzing the process of synthesizing lactic acid by taking dihydroxyacetone as a substrate. The thermostable dihydroxyacetone kinase mutant provided by the invention solves the key bottleneck that a wild enzyme is easy to thermally inactivate under industrial application conditions, and has important industrial application prospects.

The invention discloses a small-scale TELP-assisted rapid chromatin immunoprecipitation sequencing method. MNase digestion is adopted to replace ultrasonication, so that the problem of epitope masking possibly caused by cross-linking is avoided. Library construction is carried out by using a TELP method, and efficient capture is realized by using an anchor primer tailed by PolyC and labeled by biotin. Only 3 '-phosphoric acid is removed from the rSAP, preparation is made for a subsequent tailing reaction, thermal inactivation can be achieved, the purification step is omitted, a traditional terminal repair enzyme system is not needed, and TELP has high sensitivity to low-initial-quantity DNA and is suitable for trace DNA produced by ChIP-seq. And through streptavidin magnetic bead capture, all subsequent steps (washing and connecting) are performed on the magnetic beads, so that the sample transfer loss is greatly reduced. 3 '-OH is directly used for tailing, and the steps of tail end repairing and A tail adding which are most likely to cause loss in traditional library building are omitted. According to the method, histone modification can be detected only by using hundreds of cells.

The application discloses a single-stranded DNA molecular weight standard based on light-controlled self-assembly and a preparation method thereof, and comprises the following steps: S1, chemically synthesizing a DNA sequence containing a photosensitive bridging group, which can self-assemble to form a hairpin structure, and self-assembly can also occur between the hairpin structures; S2, annealing the DNA sequence, and self-assembly of individual DNA sequences to form hairpin structures; S3, mixing the hairpin structures with a nucleic acid ligase, under ultraviolet light, the photosensitive bridging group is broken, the exposed single-stranded sequence is paired with other hairpin structures through base complementation, and cascade self-assembly is realized through the nucleic acid ligase; S4, heat inactivation treatment; S5, ultraviolet light treatment is performed again, so that all the photosensitive bridging groups are broken; and S6, an electrophoresis loading buffer is added, and low-temperature preservation is carried out. The application adopts a one-pot method to rapidly prepare the DNA molecular weight standard, has the advantages of simple process, low manufacturing cost and strong expandability, and has a good application prospect.

The invention provides a bioactive nanometer device and a preparation method and application thereof, the bioactive nanometer device comprises mBSG-NH2 and a nucleic acid substance loaded on the mBSG-NH2, and the mBSG-NH2 is nanometer mesoporous borosilicate bioactive glass with the surface modified with-NH2. According to the invention, the degradability of the nucleic acid delivery carrier and the protection effect on loading, enzymolysis / thermal inactivation and the like of nucleic acid substances can be improved, and meanwhile, the transmembrane delivery and intracellular lysosome escape performance of the nucleic acid substances can be improved.

The invention relates to the field of tumor treatment equipment, and discloses a bone tumor in-situ thermal inactivation device and a thermal inactivation method, the bone tumor in-situ thermal inactivation device comprises a wrapping module, a heating module and a monitoring module; the wrapping module comprises a cylinder, sealing devices are arranged on the two sides of the cylinder, and a sealing cavity used for containing the diseased bone is formed in the cylinder. The heating module comprises a driving assembly and a heating assembly, the driving assembly is connected with the heating assembly and the barrel, the heating assembly is used for heating and storing a heating medium, and the driving assembly is used for driving the heating medium to flow between the barrel and the heating assembly; the monitoring module is used for monitoring the external surface temperature of bone cortex of a diseased bone, the central temperature of a diseased marrow cavity and the surface temperature of a vascular nerve tract of the diseased bone; according to the tumor inactivation device, the affected bone is contained in the cylinder body in a sealed mode, then hot normal saline is introduced into the cylinder body to achieve tumor inactivation, the peristaltic pump and the heating assembly are matched with the temperature sensor to control the temperature, the inactivation efficiency and effect are improved, the treatment difficulty is reduced, and the adverse effect in the inactivation process is reduced.

The application relates to a glutamine transaminase with improved thermal stability and application thereof, and belongs to the technical field of genetic engineering and protein engineering. The variant comprises a leading peptide and a mature polypeptide. The parent mature polypeptide of the variant corresponds to the region of the N terminal 4th to 13th of the wild-type SmTG mature polypeptide, and is replaced by a target sequence composed of n repeating units connected head to tail. The repeating unit has at least 80% identity with the original sequence, and is independently substituted by a specific amino acid at the corresponding 10th position, wherein at least two repeating units have different types of substitution amino acids at the 10th position. The remaining amino acid region of the parent mature polypeptide has at least 85% sequence identity with the remaining region of the wild-type SmTG mature polypeptide. Compared with the parent, the variant has a glutamine transaminase activity, and the thermal inactivation half-life at 60 DEG C is significantly prolonged by at least 0.3 times.

The application discloses a preparation method of DNA molecular weight standards based on self-assembly, comprising the following steps: S1, two single-stranded DNAs with equal length but not complete complementarity are chemically synthesized, and each single-stranded DNA is composed of two sequences, one of which is a complementary sequence, and the other is a self-assembly complementary sequence; S2, directional self-assembly is carried out in a reaction buffer solution, and a ligase is added; S3, reaction is carried out at room temperature for 0.5-10 min, the number of self-assembly is controlled by controlling the reaction time, the number of bases added by each connection is equal to the number of bases of the single-stranded DNA, and a plurality of DNA molecular weight standards with arithmetic progression of sequence length are formed; S4, heat inactivation treatment is carried out; S5, an electrophoresis loading buffer solution is added, and the DNA molecular weight standards are prepared, and the DNA molecular weight standards are stored at low temperature. The application has the advantages of simple process, low manufacturing cost, strong expandability and the like, and has a good application prospect.

The invention discloses a single-stranded DNA molecular weight standard based on light-operated self-assembly and a preparation method thereof.The preparation method comprises the following steps that S1, a DNA sequence containing a photosensitive bridging group is chemically synthesized, the DNA sequence can be self-assembled to form hairpin structures, and the hairpin structures can also be self-assembled; s2, carrying out annealing treatment on the DNA sequence, and carrying out self-assembly on a single DNA sequence to form a hairpin structure; s3, mixing the hairpin structure with nucleic acid ligase, breaking the photosensitive bridging group under the irradiation of ultraviolet light, complementarily pairing the exposed single-chain sequence with other hairpin structures through bases, and realizing cascade self-assembly through the nucleic acid ligase; s4, carrying out thermal inactivation treatment; s5, carrying out ultraviolet irradiation treatment again to break all the photosensitive bridging groups; and S6, adding an electrophoresis loading buffer solution, and storing at low temperature. The DNA molecular weight standard is rapidly prepared through the one-pot method, and the method has the advantages of being simple in process, low in manufacturing cost, high in expansibility and the like and has good application prospects.