190 results about "Thermal denaturation" patented technology

The invention provides method for therapeutic protein drug development that incorporates therapeutic and/or formulation and/or manufacturing considerations in the early screening process. The approach involves screening a plurality of different variants of a domain that have been determined to have the desired therapeutic property to identify one or more variants that have desired therapeutic and/or formulation characteristics, and constructing the full multidomain proteins using the identified domain variants. The present invention also provides a method for determining the shelf life of multidomain proteins in formulations. The method comprises determining a thermal denaturation and/or renaturation curve of a domain of the protein whose unfolding leads to aggregation of the protein in a solution. The method evaluates the shelf life of the multidomain protein based on the denaturation/renaturation curve. The invention also provides methods for engineering multidomain proteins to improve their therapeutic and/or formulation characteristics.

The invention relates to a quantitative detection method for thermal-denaturation and non-denaturation bovine alpha-lactalbumin in milk and milk products by applying an enzymolysis-liquid chromatography and mass spectrometry combination technology. The quantitative detection method comprises the steps as follows: taking a certain amount of milk or milk samples, dissolving and diluting the milk or milk samples in water to obtain solution with total protein content being about 1mg/mL; after volume metering, correctly sucking 500 mu L, adding an internal standard substance, reacting disulfide bond with dithiothreitol (DTT), alkylating to protect sulfydryl produced in reaction by iodoacetamide (IAA), and then conducting constant-temperature and constant-time enzymolysis with trypsin; and separating enzymolysis products by reversed phase liquid chromatography, conducting detection with a mass spectrum multiple reaction monitoring (MRM) manner, and calculating the result by an internal standard method. The quantitation limit of the method is 0.001g/100g; when adding amount is 0.2, 1.7 and 5.0g/100g, the recovery rate is 98.9-110.8% (n is equal to 6) and repeatability: RSD (Relative Standard Deviation) is smaller than 7.6%; and the quantitative detection method can be applicable to the quantitative detection of samples with different contents of bovine alpha-lactalbumin.

This invention relates to phytases, polynucleotides encoding them, uses of the polynucleotides and polypeptides of the invention, as well as the production and isolation of such polynucleotides and polypeptides. In particular, the invention provides polypeptides having phytase activity under high temperature conditions, and phytases that retain activity after exposure to high temperatures. The phytases of the invention can be thermotolerant and/or thermostable at low temperatures, in addition to higher temperatures. The phytases of the invention can be used in foodstuffs to improve the feeding value of phytate rich ingredients. The phytases of the invention can be formulated as foods or feeds or supplements for either to, e.g., aid in the digestion of phytate. The foods or feeds of the invention can be in the form of pellets, liquids, powders and the like. In one aspect, phytases of the invention are stabile against thermal denaturation during pelleting; and this decreases the cost of the phytase product while maintaining in vivo efficacy and detection of activity in feed.

An intelligent tissue mimicking ultrasonic phantom, which is a temperature-sensitive polymer gel having the following acoustic properties and other physical characteristics: acoustic velocity: 1500-1550 m/s; acoustic impedance: (1.50−1.60)×10⁶ Pa·s/m; density: 1.01-1.06 g/cm³; and a denaturation temperature, namely, a Lower Critical Solution Temperature (LCST) or a Volume Phase Transition Temperature at which the volume of the phantom changes, adjustable by changing the ratio of raw materials, around which there is a reversible phase transformation between the opaque phase and the transparent phase. Said gel can be a polymer of isopropylacrylamide (NIPA). Said ultrasonic phantom has a transparent appearance, and an adjustable thermal denaturation temperature; the thermal denaturation region of the ultrasonic phantom is distinct and has a well-defined boundary; the material of the phantom is stable and deterioration-resistant, and can ensure the consistency of the quality; the phantom is thermal denaturable with the appearance thereof turning white, while the phantom recovers when the heat is removed, such that it can be used repeatedly.

The invention relates to a preparation method of a raw sea cucumber which can be directly eaten. The preparation method is characterized in that internal organs are removed from a fresh sea cucumber, then the fresh sea cucumber is washed clean, and added with deionized water which is 0.5-10 times of the weight of the sea cucumber for ultrasonic processing at the temperature of 10-50 DEG C for 0.5-5 hours to obtain liquid; the obtained liquid is added with protease accounting for 0.1-5% of the weight of the sea cucumber at the temperature of 20-50 DEG C under the pressure of 0.01-0.5MPa for 0.5-10 hours to obtain solution; the sea cucumber is taken out from the obtained solution, the enzyme solution on the surface of the sea cucumber body is washed clean by clean water which is 1-5 times of the weight of the sea cucumber to obtain the raw sea cucumber which can be directly eaten. Sea cucumber protein prepared by the preparation method has no thermal denaturation, nutrient and beneficial ingredients such as sea cucumber mucopolysaccharide, sea cucumber saponin, and the like has little loss; collagen is softened but the sea cucumber does not shrink. The fresh sea cucumber has good mouth feeling and elasticity, and can be directly eaten.

The invention discloses a method and a kit for rapidly constructing a target nucleic acidsequencing library on the basis of probe capture and enrichment. The method comprises following steps and adopts reagents required for the steps: genome DNA is subjected to fragmentation; DNA end repair is performed; a probe and a single-stranded DNA fragment formed through thermal denaturation are subjected to molecular hybridization; biotin-avidinmagnetic bead separation is executed; the probe is taken as a primer for primer extension, and a complementary strand is synthesized; one end of a double-stranded DNA fragment is connected with an linker, and the other end is not connected with the linker; PCR amplification is performed; DNA fragment lengthselection is executed; the reagents are used for completing the reactions of all the steps. Compared withconventionaltarget nucleic acid enrichment technologies, the method has the advantages of good fidelity, good reproducibility, high speed and high universality.

The invention discloses a preparation method of high-toughness polyphenyl thioether alloy. The preparation method comprises the following steps: adding an antioxidant, an ethylene-methyl acrylate-glycidyl methacrylate special ternary random copolymer toughening material and carbon black in a linear polyphenylene sulfide (PPS) resin subjected to oxidative thermal crosslinking, and then fully and evenly mixing in a high-speed mixer so as to obtain a PPS resin premix, wherein the weight percentage of PPS to glass fiber to special toughening material to carbon black to antioxidant is (59.8-65.2):(25-35):(3-8):(1-2):(0.2-0.8); and carrying out mixing, extrusion molding, cooling and chopping to obtain finished alloy. The alloy obtained by using the preparation method has the advantages of high thermal denaturation stability, high tensile strength and low metal corrosion rate, and can be widely applied to the fields of electronic appliances, machinery, chemical industry, petroleum, military industry and aerospace, especially used as an enclosure material or packaging material for all types of batteries.

The invention belongs to the field of preparation of biological medical materials, and relates to a method for preparing stable albumin nano-particles by virtue of thermal denaturation. The method comprises the following steps: (1) adding vanillic aldehyde or an analogue thereof to form intermolecular disulfide bonds by virtue of inter-reaction of free sulfhydryl groups on albumin molecules under a heating condition; (2) enabling amino groups inside and among molecules to react with carboxyl so as to form amido bonds; and (3) enabling amino groups on the albumin molecules to react with aldehyde groups on vanillic aldehyde or the analogue thereof to form chemical bonds of Schiff base and the like so as to form stable nano-particles in an aqueous solution. Any organic solvent is not introduced during preparation, so that the prepared nano-particles are safe and nontoxic, and can well entrap antitumor drugs including paclitaxel, doxorubicin hydrochloride and the like. Moreover, the carrier has an oxidation reduction response in a tumor cell internal environment, and can open disulfide bonds to release drugs under the action of reducing glutathione in cells. The method provided by the invention is simple in process, convenient to operate and suitable for industrial mass production.

The invention relates to a separation and purification method for a recombinant hepatitis B core antigen. The method includes the steps of thermal denaturation and clarification; ammonium sulfate precipitation; ultrafiltration and concentration, washing filtering and liquid exchange; depolymerization; first-step molecular sieve chromatography; ultrafiltration and concentration, washing filtering and liquid exchange; repolymerization; second-step chromatography. By means of the method, the high-purity, low-host-residue and high-stability recombinant hepatitis B core antigen with a uniform granular structure can be obtained, that is to say, the method has the advantages that the antigen purity is high, the residue of host protein and host nucleic acid is low, antigen particles are uniform, and industrial enlargement is easy.

The invention relates to a tissue monitoring apparatus, a tissue monitoring method and an ablation lesion monitoring, measuring, and controlling automated algorithm incorporating diffuse reflectance spectroscopy (DRS) and/or Arrhenius model thermal denaturation kinetics for determining the characteristics of the lesion or the tissue, especially for identifying the transmurality of the ablation lesion. The invention pertains to a device for and method of real time monitoring of lesion formation as ablation is being carried out.

The invention discloses a method for raising thermal denaturation temperature of hide and hide powder through THP salt-nano clay combination tannage. The method comprises: adding softened hide or hide powder and water in a mass ratio of (0.5-1):1 to a reactor; adding a certain amount of salt and formic acid; adding THP salt and stirring for 3 to 5 hours; adding nano clay and stirring for 3 to 5 hours; extracting alkali till the pH of bath is between 5.0 and 6.0, continuing to stir for 2 hours and then standing the obtained product overnight; and stirring the obtained product for 30 minutes next day and then performing washing. The method can effectively raise the thermal denaturation temperature of hide collagen up to over 115 DEG C through the THP salt-nano clay combination tannage. Due to the specific structure of the nano clay added in the method, during alkali extraction in the later stage of tanning, tanning liquor is automatically alkalized and mitigated in effect, thereby helping to stabilize product quality, and the consumption of alkalization agent can be reduced. Meanwhile, the THP salt and the nano clay in the method containing no heavy metal salts are environment-friendly materials, and the tanning process is a clean leather-making technique.

The invention discloses an evaluation method for the degree of thermal denaturation of macromolecular collagen by using a pepsin process. The method is characterized by comprising the following steps: (1) selection of a raw material: a step of selecting leftovers of aquatic product processing-fishskin as the raw material; (2) immersion and dissolving: a step of adding acetic acid with a concentration of 0.01 to 1.0 mol/L into the raw material to obtain a collagen solution; (3) heat pretreatment: a step of heating the collagen solution, shaking the solution every five minutes during heating and carrying out rapid cooling after heating is finished; (4) enzymatic hydrolysis: a step of adding pepsin into the collagen solution, carrying out a heat reaction and adding phenylmethylsulfonyl fluoride after the heat reaction is finished so as to terminate the reaction; and (5) preparation of an electrophoresis sample and electrophoresis. The invention has the following advantages: used equipment is simple; more comprehensive and visual reflection of the denaturation state of protein is realized.

The invention discloses a method for extracting hemoy lobin and superoxide dismutase from bloods of livestock, which comprises the steps that: after going through an anti-freezing treatment, the fresh bloods of livestock is centrifuged to collect corpuscles, and after hemolysis, heating treatment is carried out so as to extract the hemoy lobin and SOD crude extracted liquid; SOD refined products are obtained after the SOD crude extracted liquid goes through treatments of thermal denaturation, super-filtration concentration, fractionated precipitation of acetone and absorption by ion exchanger. The method of the invention has simple operation and low production cost, is suitable for large-scale industrialized production, and can be used for simultaneously extracting the SOD and hemoy lobin in the bloods of livestock, thereby achieving the highly effective recovery of a plurality of protein resources from the blood of livestock. The extracted hemoy lobin contains salts such as sodium chloride and potassium chloride, etc which are harmless to the human body without containing copper ions. Therefore, the extracted hemoy lobin can be served as food for human beings and livestock, and also can be used for further producing hemoy lobin products such as hemachrome and decolored globin, etc.

A tissue composition monitoring apparatus that includes a catheter with an optical sensor for tissue composition monitoring and ablation lesion determination via an automated algorithm incorporating Arrhenius model thermal denaturation kinetics for determining the characteristics of tissue for example the transmurality of the ablation lesion.

A phenylenediamine derivative represented by following formula (I) or (II):

wherein R₁ and R₂ each represents a hydrogen atom, a lower alkyl group, or a lower alkoxy group; R₃ represents a hydrogen atom or a methyl group; R₄ represents a methyl group or an ethyl group; and n and m each is 1, 2, or 3;

wherein R₁ and R₂ each represents a hydrogen atom, a lower alkyl group, a lower alkoxy group, or a cyano group; and n and m each is 1, 2, or 3, is disclosed.

These phenylenediamine derivatives are effectively used as antioxidants for rubbers, which scarcely cause vanishing by evaporation or a thermal denaturation even under a high-temperature condition of 150° C. or higher.

The invention discloses a method for preparing corn protein foaming powder by enzymatic hydrolysis of com gluten meal. The method comprises the following steps of: pre-treating the com gluten meal by adopting enzymolysis of double enzymes, namely cellulase and alpha-amylase, centrifuging and washing to obtain corn protein concentrate; dissolving the corn protein concentrate into water, and performing thermal denaturation treatment at the temperature between 80 and 90 DEG C; adding sulfite or meta-disulfite for chemical modification; and adding neutral protease or alkali protease for hydrolysis, filtering, drying the clear solution, and thus obtaining a corn foaming protein product. The corn protein foaming powder prepared by pre-treating the com gluten meal by adopting enzymolysis of the double enzymes has high protein content, good foaming effect and high foaming stability; and the application range of the com gluten meal is further widened, the additional value of the deep processing products of the com gluten meal is improved, and the technological content and the quality of the deep processing products of the com gluten meal are greatly improved.

The invention discloses a manufacturing method of a high-temperature resistant and corrosion-resistant polyphenyl thioether composite tube. The manufacturing method comprises the following steps of: adding fillers such as a thermal stabilizer, an inorganic filler and the like into polyphenyl thioether resin, and then mixing the materials fully and uniformly in a high-speed stirring machine to obtain a polyphenyl thioether resin premix compound; mixing and extruding the premix compound through a first-stage twin-screw extruder and introducing the premix compound into a single-screw extruder; extruding 3 to 6 layers of a fiber cloth formed by mix-twisting knitting a cylindrical basalt fiber and modified aramid fiber III after thermal expansion and contraction and a polyphenyl thioether composite fusant out of a tubular die on the head section of the extruder by the single-screw extruder; and cooling a pull tube into the polyphenyl thioether composite tube. The polyphenyl thioether composite tube manufactured by the method has the advantages of high thermal denaturation stability, corrosion resistance and high air tightness, and can be widely used in the fields of chemical industry, petrochemical industry, water supply and sewerage works, special industries and the like.

The invention discloses hypoallergenic soybean peptide whole wheat flour, as well as a preparation method and application thereof. The preparation method comprises the following steps: (1) mixing the soybean protein powder with water to obtain a soybean protein solution, and performing thermal denaturation on the soybean protein solution to obtain a denatured protein solution; (2) adjusting the pH value of the denatured protein solution to 6-9, adding neutral protease and performing first enzymolysis to obtain a first enzymatic hydrolysate; (3) adding alkaline protease and flavourzyme into the first enzymatic hydrolysate to perform second enzymolysis, and performing enzyme deactivation to obtain a second enzymatic hydrolysate; and (4) homogenizing the second enzymatic hydrolysate to obtain the hypoallergenic soybean peptide whole wheat flour. By adopting the preparation method, the sensitization of the soybean protein can be completely eliminated, the utilization rate of the protein is high and the mouth feel of the product is effectively guaranteed, and the prepared hypoallergenic soybean peptide whole wheat flour can be widely used in the milk powder or healthcare product.