409 results about "Glutamine transaminase" patented technology

The invention relates to a method for preparing an edible wrapping film, which comprises the steps of preparation of modified solution of fish skin collagen and film formation. The method is characterized in that: the preparation of the modified solution of the fish skin collagen comprises the following steps of: preparing the fish skin collagen into aqueous solution of which the g/ml is 6.67 percent, adding glutamine transaminase, and heating to dissolve at the temperature of between 40 and 50 DEG C; adding 2 percent of solution of chitosan acetate according to a volume ratio of 1-2:1, and heating 30 minutes at the temperature of between 40 and 50 DEG C to prepare the modified solution of fish skin collagen; and adding 20 volume percent of edible plasticizer to prepare film-forming solution, and coating the film-forming solution on a glass plate and drying in a thermostat to obtain the product. By modifying the fish skin collagen by combining the glutamine transaminase with the chitosan, coating and drying, the edible wrapping film is prepared; and the prepared film product has the advantages of high mechanical strength, strong breaking strength, safety, no toxin and edibility, and can replace plastic films or plastic bags to be applied to the fields of foods, medicaments and cosmetics.

The invention relates to a three-dimensional (3D) bio-printed brain tumor in vitro model and a construction method thereof. The brain tumor in vitro model is obtained from a brain tumor cell-containing hydrogel system by preparing hydrogel fibers and constructing with a 3D bio-printer, wherein the hydrogel fibers has a diameter of 0.16-0.75mm, and has a volume filling percentage in the brain tumor in vitro model of 40-90 percent; the brain tumor cell-containing hydrogel system is prepared from the following raw materials: hyaluronic acid, sodium alginate, gelatin, glutamine transaminase and brain tumor cells. According to the brain tumor in vitro model, the 3D structure can be well maintained in the later culturing process, the problems of insufficient nutrition supply for cells inside large-sized hydrogel and biological characteristic and function loss of brain tumor cells when an existing brain tumor model is subjected to in vitro two-dimensional (2d) culture can be effectively solved.

The invention discloses a new technique for preparing an edible membrane by glutamine transaminase modified protein, which has main materials such as isolated soybean protein and wheat gluten protein and adopts transglutaminase for modification, thus achieving the complex edible membrane with good performance. The invention has advantages in the following aspects: 1. the strengths of both single substrate material isolated soy protein film and wheat gluten protein film are fully exerted so as to make the edible membrane with good tensile strength and extensibility; 2. the transglutaminase is adopted for the first time as a modifier to modify the protein composite membrane, thereby greatly enhancing the tensile strength and getting the compound edible membrane with good performance; and 3. the invention has the greatly expanded scope of applications of protein and provides a new effective approach for solving the environmental pollution. The edible high quality composite membrane is applied to food packaging, and can be directly eaten with other food, and some can be used as feeding materials, completely free of environmental contamination, so the invention is an authentic green packaging material.

The invention relates to a microencapsulation method for preparing a hydrotropic substance serving as a core material by using a complex coacervation method. The method is simple in process and low in cost, and the product has high encapsulation rate. The method comprises the following steps of: (1) weighing specific protein and polysaccharide in a certain ratio, stirring and dissolving in hot water to form a wall material solution; (2) weighing a certain mass of hydrotropic core material substance, adding an oil phase substance and an emulsifier in a certain mass ratio, and performing high-speed dispersion to form water/oil (W/O) emulsion; (3) directly pouring the emulsion into the wall material solution, stirring at the constant temperature of 45 DEG C, regulating pH by using 10 percent acid, and reacting for 15 minutes; (4) cooling to the temperature of below 15 DEG C, regulating the pH to 6.0, and adding glutamine transaminase for solidifying; and (5) filtering to obtain a wet capsule product. A dry microcapsule product can be obtained by freeze drying or spray drying.

The invention discloses a liquid enzyme preparation and a preparation method thereof and mainly solves the technical problem that a glutamine transaminase liquid preparation is hard to preserve at the normal temperature. According to the technical scheme, the enzyme preparation is a liquid preparation of glutamine transaminase EC2.3.2.13, and the constituent content of the enzyme preparation is that enzyme activity of the glutamine transaminase liquid preparation is 10-1000 u/ml, the weight volume percentage content of a water activity conditioning agent is 30-80%, the weight volume percentage content of a redox potential conditioning agent is 0.0075-1%, the weight volume percentage content of a food preservative is 0-0.1%, and a pH conditioning agent is supplemented to 100% in volume. The preparation method of the liquid enzyme preparation comprises the steps of enzyme liquid purification, mixing, sterilization and bottling to obtain a finished product. By means of the liquid enzyme preparation and the preparation method thereof, the enzyme activity of the enzyme preparation preserved for six months at the normal temperature can be maintained at 80% or above, the character is stable, no microbial spoilage is caused, and the using effect is good.

A streptomyce shygeroscopicus (CCTCC No.M203062) able to generate glutamine transaminase wigh high output is extracted from the soil of milk cow farm through plate screening, primary fermenting, flask culture, comparing test with standard color tape, and enzyme activity test. Said glutamine transaminase is prepared by deep fermentation.

The invention relates to a method for preparing a microcapsule taking a hydrophobic substance as a core material by a complex coacervation method. The method has the advantages of simple process and relatively lower cost, and the product has relatively higher encapsulation efficiency. The method comprises the following steps of: (1) weighing gelatin and carboxymethylcellulose in certain proportion, and stirring and dissolving the gelatin and the carboxymethylcellulose in hot water; (2) adding hydrophobic substance in certain mass ratio and dispersing the hydrophobic substance for 2 minutes at a high speed to form emulsion; (3) stirring the emulsion at the constant temperature of 45 DEG C, adjusting the pH of the emulsion to be 4.4 to 4.8 with a 10 percent ethylic acid and reacting the emulsion with the ethylic acid for 5 minutes; (4) cooling the emulsion until the temperature is below 15 DEG , adjusting the pH of the emulsion to be 6.0 and adding glutamine transaminase for solidification; and (5) filtering the mixed solution to obtain a wet microcapsule product, and freeze-drying or spray-drying the wet microcapsule product to obtain a dried microcapsule product.

A preparation method of soybean protein isolate transparent hydrogel with high gel strength and a high swelling property is provided, comprising: using defatted soybean meal as a raw material, preparing high-purity soybean protein isolate by alkali extraction and acid precipitation; ultrasonic pretreatment, performing ultrasonic treatment on a soybean protein isolate dispersion liquid with concentration of 5% (w/v) for 30 to 90 min; preparing a protein/polysaccharide aggregate solution, mixing chitosan with the soybean protein isolate subjected to the ultrasonic treatment in a mass ratio of 2-7%, performing heat treatment at temperature of 95 DEG C for 30 min, and then cooling to room temperature; adding a glutamine transaminase to the foregoing thermal aggregate solution in a mass ratio of 4-8% (enzyme/protein, m/m); eliminating air bubbles by centrifugation; performing incubation at temperature of 55 DEG C for 4 h; performing enzyme deactivation by heating in water bath at temperature of 95 DEG C for 10 min; performing ice-bath cooling; and placing the mixture in a refrigerator of 4 DEG C for 24 h. The invention is added to food production as a substitute for food additives, and improves an additional value and quality of soybean food, thereby implementing low-carbon sustainable production.

The invention provides a yeast extract and a preparation method thereof. The method comprises the following steps: using a yeast culture with the protein content higher than 60 percent as raw materials to be cultured in a culture medium with rich nitrogen sources to obtain yeast cream; then, adding a certain amount of prolease and glutamine transaminase into the yeast cream; thus obtaining the yeast extract through a series of processes. The glutamic acid content in the yeast extract is higher than 10 percent. According to the preparation method provided by the invention, the yeast extract with the glutamic acid content higher than 10 percent can be prepared in a large scale.

The invention belongs to the field of food and medicine and relates to a method for improving the viscosity of gelatin by using a glutamine transaminase for catalyzing gelatin crosslinking. According to the method, gelatin molecules are catalyzed to crosslink by using the glutamine transaminase at a certain pH value and temperature, the adjustment on the viscosity of the gelatin can be realized through controlling the reaction time and the addition of the glutamine transaminase. The method can be widely applied to bone gelatin and skin gelatin which are prepared by acid, alkali and enzyme methods. The method disclosed by the invention is safe and non-toxic, is simple in process and is applicable to gelatin production plants or application units; and the viscosity of the gelatin is improved through the method disclosed by the invention, so that the quality and application value of the gelatin are improved.

The invention relates to a high-protein tilapia fish ball and a preparation method thereof and belongs to the field of food processing technology. The invention relates to a fish ball, in particular relates to the high-protein tilapia fish ball and also a method for producing the high protein tilapia fish ball by utilizing a superhigh pressure technology. According to the preparation method, fish meat and fish skin of tilapia fish are used as main ingredients, soy protein, glutamine transaminase, konjac powder, sodium lactate, salt, granulated sugar, monosodium glutamate, white pepper powder and yellow wine are added, a superhigh pressure device with a temperature control device is utilized for processing the fish ball, pressure is controlled to be 200-600MPa, temperature is controlled to be 65-80 DEG C, and action time is controlled to be 10-20min to prepare the high-protein tilapia fish ball. The high-protein tilapia fish ball is good in flavor, high in protein content, compact in structure and good in elasticity, water-retaining property and anti-freezing effect.

A process for preparing dried sea cucumber includes such steps as pretreating in the water or the aqueous solution of salt at 40-80 deg.C under 100-400 MPa for 10-30 min, and putting the pretreated sea cucumber in the glutamine transaminase liquid at 40-80 deg.c for 30-90 min. Its advantages are short period, high content of mucoitin and short water renaturation time.

The invention provides a formula for secondarily preparing yoghourt with high-index base stock. The formula comprises the following components by weight part: 80-100 parts of milk, 0-15 parts of white granulated sugar, 0-5 parts of single cream, 0-5 parts of concentrated whey protein, first fermentation culture, secondary fermentation culture, 0-0.5 part of stable thickening emulgator, nutrient supplement, glutamine transaminase, lactase and chymosin. The formula has the beneficial effects that the fermentation base stock is uniformly produced, the products in different forms are variously produced, the formula is conveniently sold in catering terminal, the formula can meet the requirements of various clients and much more yoghourt need not be stored.

The invention discloses a method for improving yogurt coagulability through glutamine transaminase, and belongs to the technical field of milk product processing. The method comprises the following technological steps of 1, raw milk microfiltration; 2, mixing, wherein 0.001-0.005 mg/kg of casoid flour is added into the raw milk, and the mass fraction of alpha-casein in the casoid flour is 70% or above; 3, homogenizing; 4, pasteurization; 5, inoculation, wherein the sterilized milk is inoculated with lactic acid bacteria, 0.001-0.005 mg/kg glutamine transaminase is added, and even mixing is performed; 6, fermentation. Compared with traditional set yogurt, by means of the method, the yogurt has better coagulability and smoothness, and whey precipitation is reduced.

The invention discloses a glutamine transaminase with improved heat stability and application thereof. High-efficiency expression of microbial transglutaminase (MTG) in escherichia coli serves as a modification platform, a label facilitating improvement of heat stability is added at the C end of MTG maturase, preference is given to IGCIILT to obtain a mutant strain with good enzymatic property, and the heat stability is improved by 2.5 times and 3 times. Modified enzyme is suitable for industrial application, the production cost can be reduced, and the production efficiency can be improved.

The invention discloses a processing method of a shrimp flavored surimi product. The processing method comprises the following steps: (1) performing fast curing pretreatment on a frozen product of frozen shrimp byproducts, thus obtaining the shrimp byproducts after pretreatment; (2) half-thawing 100 parts of frozen surimi, then adding 0.2-0.4 part of composite phosphate to perform empty beating/empty chopping, then adding 2-3 parts of common salt to perform salt beating/salt chopping and then, adding 4-10 parts of starch, 3-10 parts of plant protein, 10-25 parts of shrimp byproducts after pretreatment, 0.05-0.1 part of glutamine transaminase, 3-5 parts of seasonings and 10-30 parts of ice water to perform mixed beating/mixed chopping; (3) molding slurry obtained in the step (2) to obtain molded slurry; (4) immediately performing gelation on the molded slurry; and (5) performing high-temperature curing on a matter obtained in the step (4) to obtain the shrimp flavored surimi product. The shrimp flavored surimi product processed by adopting the method disclosed by the invention has good gel strength.

The invention relates to a transglutaminase zymogen gene of Streptomyces hygroscopicus and the expression thereof, pertaining to molecular biology field. The invention provides the gene sequence of transglutaminase zymogen of Streptomyces hygroscopicus CCTCC M203062 (China patent: 03152956.9, 2003), and further provides a vector system and a host system that has soluble express of the zymogen of the gene code, a part of soluble expressed zymogen can be obtained through the expression system, and the zymogen can be treated by trypsin to prepare activated transglutaminase.

The invention discloses a mutant of glutamine transaminase expressed by an active form, and belongs to the field of gene engineering and fermentation engineering. A genetically engineered bacterium po1h/hpro-mTG of high-output glutamine transaminase is structured by using yarrowia lipolytica as a host. The bacterial strain is high in enzyme production level; the fermenting enzyme activity of a shake flask is up to 11.7 U/mL, and improved by 106 times in comparison to that before transformation; the fermenting enzyme activity of a fermenting tank is up to 43.7 U/mL. Through co-expressing proteases TAMEP and hpro-mTG, the activity expression of glutamine transaminase is realized; the fermenting enzyme activity of the shake flask can reach 6.7U/mL, and the fermenting enzyme activity of the fermenting tank can reach 21.4U/mL. The fermenting enzyme production level of the recombinant bacteria is high, the production cost of the glutamine transaminase is reduced; the mutant is good for the industrial production of the glutamine transaminase.

The invention discloses a glutamine transaminase mutant with improved enzymatic activity, which belongs to the field of enzyme engineering. The site-specific mutagenesis is performed on glutamine transaminase, an amino acid residue close to an active site of the glutamine transaminase is changed, so that the catalytic efficiency of the glutamine transaminase is improved, and the enzymatic activityof the glutamine transaminase is further improved. Recombinant yarrowia lipolytica with improved enzymatic activity is established by the glutamine transaminase mutant, the enzymatic activity of theglutamine transaminase is improved by 1.45 times compared with an original strain, the enzymatic activity of the shake flask fermentation can reach 16.995U/mL, and the enzymatic activity of the fermenting tank fermentation can reach 59.85U/mL which is the highest fermentation value reported at present.

The invention discloses a flour improver for instant frozen dumplings, a method for manufacturing the flour improver and application thereof. The flour improver for the instant frozen dumplings comprises, by weight, 2-5 parts of xanthan gum, 2-4 parts of guar gum, 2-4 parts of monostearin, 5-9 parts of stearic calcium and sodium lactate, 1-4 parts of composite phosphate, 1-3 parts of glutamine transaminase and 2-6 parts of sodium chloride. The composite phosphate comprises tetrasodium pyrophosphate, sodium tripolyphosphate and sodium hexametaphosphate. The method includes respectively sieving the xanthan gum, the guar gum, the monostearin, the stearic calcium and sodium lactate, the tetrasodium pyrophosphate, the sodium tripolyphosphate, the sodium hexametaphosphate, the glutamine transaminase and the sodium chloride by the aid of Number-CB36 sieves; mixing the xanthan gum, the guar gum, the monostearin, the stearic calcium and sodium lactate, the tetrasodium pyrophosphate, the sodium tripolyphosphate, the sodium hexametaphosphate, the glutamine transaminase and the sodium chloride with one another to obtain the improver for the instant frozen dumplings. The flour improver, the method and the application have the advantages that problems of frost cracking and the like of dumpling wrappers of existing instant frozen dumplings during instant freezing, mechanical packaging and low-temperature storing can be solved by the aid of the improver for the instant frozen dumplings, the smoothness, the boiling fastness and the freeze-thaw stability of the instant frozen dumplings can be enhanced, and the taste and the appearance of the instant frozen dumplings can be obviously improved.

The invention relates to the technical application field of foods and particularly discloses a method for preparing normal-temperature fish intestines by virtue of glutamine transaminase and a compound thickening agent. According to the method, health-source collagen powder and minced fish are taken as main raw materials for preparing the normal-temperature fish intestines by virtue of the glutamine transaminase and the compound thickening agent through processes of vacuum chopping, pulping, stuffing preparation, casing encapsulation and high-temperature steaming sterilization; and the method is a novel processing method for preparing the normal-temperature fish intestines from the main raw material, namely collagen, by virtue of specific functionalities of the glutamine transaminase and the compound thickening agent. According to the method for preparing the normal-temperature fish intestines, the problem that conventional minced fish type sausages cannot resist the high-temperature steaming sterilization is solved, the original elasticity and texture of the product are preserved, and the product is relatively good in taste, relatively convenient to eat and relatively safe and sanitary. The preparation method can meet the requirement on the guarantee period of the product in the links of normal temperature circulation and storage and the requirement of consumers on the food safety and hygiene.

The invention discloses a recombined meat adhesive and a preparation method and application thereof, belonging to the field of food processing. The recombined meat adhesive comprises glutamine transaminase, non-meat protein and dietary fiber, has the advantages of low production cost, good adherence effect, great adherence strength to meat slices or meat blocks, little melting loss and boiling loss, great recombined meat tenderness and good flakiness, can effectively ensure the adherence effect, improves the demand of people for dietary fibers and increases the added value of products. The recombined meat prepared by the recombined meat adhesive has the adhesive property higher than or equal to 70g*cm<-2>, decreases the hardness by 62.8 percent and reduces the shearing force by 22.9 percent; the prepared raw and fresh recombined meat or cooked recombined meat has no obvious color difference (p is larger than 0.05) from one-piece meat and has no obvious taste difference (p is larger than 0.05) from the one-piece meat by sensory test.

The invention provides a gelatin composition. The gelatin composition comprises hydroxylated gelatin, microbial glutamine transaminase and protein glutaminase, wherein the hydroxylated gelatin is 20-60%proline-hydroxylated gelatin. The gelatin composition has an extremely-good bleeding stopping effect at a temperature in a range of 4-10DEG C. The invention also discloses a preparation method of the gelatin composition and an application of the gelatin composition.

The invention discloses a method for preparing a textured soybean protein. The method comprises the following steps: firstly, sufficiently and uniformly mixing high-gluten wheat proteins and soy isolate proteins so as to obtain premixed plant proteins; secondly, performing high-speed chopping and mixing on the plant proteins and water till moisture of materials is uniformly distributed, adding glutamine transaminase, chopping till the materials are uniformly distributed, and leaving to stand for 0-48 hours at 0-5 DEG C so as to obtain a plant protein base material; further crushing or screening low temperature soy flour, dietary fibers and starch till the granularity is greater than 80 meshes; mixing the plant protein base material, the soy isolate proteins, the nano-grade dietary fibers,the low temperature soy flour and the starch, putting into a conditioner, adding water, and heating to adjust till the moisture content is up to 35-40% so as to obtain an adjusted base material; and finally performing extrusion molding on the adjusted base material, extruding the adjusted base material from the outlet of a mold, and performing cutting and drying, thereby obtaining textured soybeanprotein. The textured soybean protein has the characteristics of high hydroscopicity, high elasticity and fine fiber-like products.

The invention discloses gluten protein colloid granules and a preparation method and application of the gluten protein colloid granules. The preparation method comprises the following steps: gluten protein is subjected to crosslinking reaction under the effect of glutamine transaminase so as to form gluten protein colloid granules; micro hydrophilic molecules with primary amine groups are added into the reaction system, and are at least one of L-lysine, glucosamine and L-glutamic acid, and the mass ratio of micro hydrophilic molecules with primary amine groups to the gluten protein is 1 to (10-100). According to the invention, the micro hydrophilic molecules with primary amine groups are added into the reaction system; the gluten protein is subjected to crosslinking among molecules and within molecules, and crosslinking reaction is performed together with the micro hydrophilic molecules with primary amine groups; on one hand, glutamine or asparaginate in the gluten protein can be prevented from being subjected to deamidation reaction by glutamine transaminase, and on the other hand, because the micro hydrophilic molecules with the primary amine groups contains electrified groups, relatively high surface electric charge is given to the gluten protein.

The invention discloses a production method of recombinant glutamine transaminase. The production method comprises the following steps of 1 fermentation of recombinant glutamine transaminase, 2 cell collection and lysis after fermentation, 3 obtaining and purification of an inclusion body and 4 renaturation of the glutamine transaminase. According to the method, target protein exists in the inclusion body form by adopting high temperature culturing and inducing in the fermentation process, therefore, the problem that the target protein generates a crosslinking reaction in cells to influence normal growth of thalli is prevented, the expression quantity of the target protein is increased, and the inhibition effect of metabolic by-products is reduced; the raw material utilization rate is increased, and therefore the production cost is reduced; in addition, the processes are simple, the obtained glutamine transaminase is high in quality and low in cost, and the production method is suitable for being applied to industrialized production.