64 results about "In vitro digestion" patented technology

The invention discloses a CRISPR/Cas9-mediated large DNA fragment assembling method. Specifically, the invention provides a nucleic acid construct capable of carrying out constitutive expression of Cas9 in yeast; the nucleic acid construct contains a yeast Tef1 promoter operationally connected with a Cas9 gene, a replication origin from pBR322 and a screening mark thereof, and a replication region from CEN6ARS4 and a screening mark thereof; and the nucleic acid construct is in the form of single-copy replication in the yeast and in the form of high-copy replication in Escherichia coli. The invention also provides a nucleic acid construct capable of carrying out constitutive expression of sgRNA in yeast, a nucleic acid construct used as a receptor vector and a DNA assembling method. According to the invention, two or more to-be-assembled large DNA fragments are successfully assembled in microzyme to form a large plasmid in one shot; so low-efficiency in-vitro digestion recovery, genetic transformation and the like of large DNA fragments are avoided, and the method provided by the invention is more convenient and efficient compared with traditional methods.

The invention belongs to the technical field of plant processing and in particular relates to a method for improving the bioavailability of iron and zinc elements of broad beans. The broad beans are low in cost, contain abundant microelements and proteins and have a certain advantage to dietary nutrition of people. Phytic acid which is contained in cotyledons of the broad beans can be combined with proteins and metal ions to reduce the bioavailability of the proteins and the metal elements. The deficiency of iron and zinc elements has certain universality, and the iron and zinc elements play an important role in intelligence development of children and physical health of adults. Most people take vegetarian diet as staple food in China, wherein the broad beans are popular bean crops, and carrots and spinaches are popular vegetables. The carrots and spinaches contain beta-carotene; and according to the method disclosed by the invention, the fact that the bioavailability of the iron and zinc elements in the broad beans can be improved by adding the carrots and spinaches into raw broad bean flour or cooked broad bean flour is discovered by using the carrots, spinaches and the broad bean flour to do an in-vitro digestion experiment, and therefore the nutritional value in use of the broad beans is increased.

The invention discloses a preparation method of a layer-by-layer self-assembled double-modified liposome. The preparation method comprises following step: lecithin and cholesterol are taken as wall materials, and a nano liposome is prepared by thin-film dispersion-dynamic high pressure microfluidization method; and layer-by-layer self-assemble technique is employed for further treatment, wherein primary amino group on chitosan molecular chains is taken as positive charge, carboxyl on sodium alginate molecular chains is taken as negative charge, polyelectrolyte films are formed layer by layer by electrostatic interaction between the positive charge and the negative charge, and the polyelectrolyte films are assembled onto the surface of the nano liposome so as to obtain the sodium alginate and chitosan double-modified liposome. Average particle size of the double-modified liposome is 330.6+-37.3nm, zeta potential is -15.79+-0.697mV, and distribution coefficient is 0.65+-0.048. It is shown by the results of in vitro digestion experiment that in vitro digestion stability of the double-modified liposome is higher than that of unmodified liposome; and release rate of fluorescent substance calcein encapsuled by the double-modified liposome after 120min of digestion is just 38+-2%, and that of fluorescent substance calcein encapsuled by the unmodified liposome is 58+-2%.

The invention relates to a method for determining poultry metabolizable energy of corn quickly by utilizing an in vitro digestion method. The method is characterized in that corn is digested through an in vitro two-step enzymic method (pepsase-pancreatin), a mathematical model on in vitro disappearance rate and metabolizable energy can be built as per the regression analysis on the in vitro disappearance rate and actually-measured metabolizable energy of corn, and the mathematical model can be used for quickly estimating the poultry metabolizable energy of corn. Compared with the data in a used feed ingredient and nutrition value table, the metabolizable energy value of corn, predicted by utilizing the mathematical model built by the invention, can ensure the accuracy of poultry feed mixing well and ensure the playing of production performance.

The invention belongs to the field of biomedicine and particularly relates to a preparation method of pluronic F127 curcumin liposome. The pluronic F127 curcumin liposome is prepared from phospholipid, cholesterol, pluronic F127 and curcumin by means of film dispersion in conjunction with dynamic high-pressure microjet through the treatments such as dissolving, film forming, hydration and dynamic high-pressure microjet. The pluronic F127 curcumin liposome prepared by using the preparation method has particle size of 70.3+/-1.0 nm, dispersion coefficient of 0.279+/-0.004, and encapsulation rate of 89.8+/-0.7%. The pluronic F127 curcumin liposome has the advantages of small particle size, narrow dispersion range and good stability, has good storage stability, and can provide improved in-vitro digestion stability and bioavailability for traditional curcumin liposomes.

The present invention discloses a blood glucose generation index in-vitro test method; according to the method, first, moisture, ash, fat and protein of a food sample are detected to obtain the amount of the food sample containing 1g of carbohydrates; by simulating of digestion of 1g of the carbohydrates of the 1g of carbohydrates by human body digestive system, the sample is taken for testing at different digestion time points, the starch consumption rate and the blood glucose level are calculated, and blood glucose generation index can be obtained by a theoretical calculation formula. According to the blood glucose generation index in-vitro test method, by in-vitro simulation of the in vitro digestion, the detection time is reduced, the detection requirement is reduced, and the problem of a significant amount of consumption of manpower and resources of in-vivo detection can be solved.

The present invention relates to biological health article, and is especially the production process of deer blood wine. The deer blood wine is prepared through enzymolysis, filtering and pasteurization. The enzymolysis is used to replace in vivo digestion process to make deer blood protein cracking into peptides and amino acids as the nutritive matter for the consumer to absorb directly, and this can reduce the consumer's load in digestion and utilize fully the deer blood resource. The enzymolysis condition is one simulation of in vivo environment to ensure the complete absorption of the nutrients components. The present invention can ensure the full absorption of protein enzymolyzing liquid other effective components.

The invention discloses a porcine somatostatin gene editing site and application thereof. The nucleotide sequence is as shown in SEQ ID NO:1. By injecting sgRNA and Cas9mRNA containing the coding sequence into porcine embryos, site-directed mutagenesis of porcine SST gene is realized. Through the CRISPR-Cas9 technique, porcine endogenous gene SST is edited at the embryo level. Statistical resultsshow that the in-vitro digestion activity is 65% after SSA luciferase detection at the site, porcine SST gene can be knocked out at the embryo level, and point mutation of SST is formed in cells. Theporcine somatostatin gene editing site is of great significance for promoting application of the endogenous gene knockout or exogenous gene site-specific integration technology in the research and production of transgenic pigs.

The invention discloses a method for preparing a functional V-type yellow dextrin-emulsifier complex, and belongs to the field of processing of functional food ingredients. High-amylose corn starch is subjected to amorphous treatment by adopting a high-temperature preheating method, so that a glucosidic bond and a secondary bond of a starch molecular chain are broken, thus obtaining yellow dextrin with a loose single-helix structure; and compared with starch, the yellow dextrin has higher capability of complexing with an emulsifier. The method comprises the following steps of: performing amorphous treatment on the amylose corn starch at the high temperature between 150 and 160 DEG C for 150 to 180 minutes, and cooling to 25 DEG C; and adding the emulsifier (palmitic acid, oleic acid or monoglyceric stearate) which is 2 percent of the mass of the high-amylose corn starch, performing high-temperature complexing reaction at the temperature of 160 DEG C for 20 to 30 minutes, cooling to 25DEG C, smashing and screening, thus obtaining the functional V-type yellow dextrin-emulsifier complex. A result of an in vitro digestion experiment shows that the glycemic index (GI) of the prepared yellow dextrin-emulsifier complex is 43 to 55, so that the yellow dextrin-emulsifier complex is a functional food ingredient with a low GI value. Furthermore, the production process is favorable to industrial production and is wide in market potential.

The invention provides an assessment method for the health risk to people of different ages caused by heavy metals in offshore edible shellfishes based on bioavailability. The assessment method comprises the following steps of obtaining concentration data of the heavy metals in the edible parts of the to-be-assessed shellfishes, body weight data of consumers of different ages in an assessment areaand shellfish consumption data; through an in-vitro digestion model, determining the bioavailability of the heavy metals in the shellfishes to the human body; according to the concentration of the heavy metals in the shellfishes and the characteristics of the bioavailability of the heavy metals to the human body, by using a weekly intake, carcinogenic health risk and non-carcinogenic health riskassessment method, obtaining the health risk caused by the heavy metals when the consumers eat the shellfishes. Based on the bioavailability of the heavy metals in the shellfishes to the human body, by considering the differences of the intake rate and the body weights of people of different ages to the health risk, the accuracy of the assessment result of the health risk caused by the heavy metals taken by the consumers eating the edible shellfishes is improved.

The invention relates to the field of medicinal preparations, and relates to a rapid-dissolution mitiglinide preparation, and a preparation method and a detection method thereof. The prescription of the preparation comprises 4-6 parts of a mitiglinide raw medicine, 25-45 parts of lactose, 15-35 parts of microcrystalline cellulose, 15-35 parts of starch, 1.5-5.5 parts of hydroxypropyl methylcellulose E3 or hydroxypropyl methylcellulose E5, 3-10 parts of sodium carboxymethyl starch and 0.05-0.3 parts of magnesium stearate. The rapid-dissolution mitiglinide preparation has the advantages of easy obtaining of auxiliary materials, low cost, simple preparation method, fast in vitro digestion, realization of the 10min dissolution rate of various dissolution media reaching 90% or above, and stable quality.

The invention provides a method for screening an exogenous carbohydrase spectrum of chicken feed. The method comprises the following steps: selecting a target chicken feed; setting the type and the dose level of the added exogenous carbohydrases; in-vitro simulating gastrointestinal digestion of chicken; detecting the in-vitro digestion emergy of the feed; and analyzing the optimal carbohydrase spectrum of the target feed. According to the method, the animal digesting process is simulated in vitro, and the acting effect of the carbohydrases is represented by using the in-vitro emergy, so that the optimal exogenous carbohydrase spectrum of the chicken feed can be quickly obtained.

The invention relates to a premix for fermented total mixed rations (TMR) for dairy cows, which comprises the following components: dairy cow fermented TMR complex enzyme, urease inhibitor, vitamins A and D, vitamin E, propionic acid-producing lactic acid bacteria, calcium formate, calcium sulfate, sodium salt, zinc sulfate pentahydrate, manganese sulfate pentahydrate, copper sulfate pentahydrate, 1 percent of iodine, 1 percent of selenium and 1 percent of cobalt. The premix is reasonably mixed, contains complete, rich and reasonably-proportioned nutrients and can accelerate the fermentation and in-vitro digestion of the fermented TMR, reduce the generation of ammoniacal nitrogen, be stored conveniently after fermentation, keep the health of dairy cows, fully meet the needs of rumen microorganisms for growth, supplement vitamins, macroelements and microelements to milk daily ration, prevent various diseases caused by the shortage of nutritive elements, promote the normal development of the dairy cows, effectively improve milk production period, milk yield and milk quality, regulate body metabolism and improve immunity and fertility.

The invention discloses a method for preparing antihypertensive peptide by enzymolysis of walnut meal with compound protease, which belong to the technical field of food-borne protein deep processing.The protease preparation is screened and compounded, and enzymolysis process conditions are optimized, so that the walnut protein source antihypertensive peptide with high activity is prepared. The optimal process conditions for enzymolysis of walnut protein are as follows: the ratio of compound enzyme is 1: 2 (alkaline protease: neutral protease), the substrate concentration is 4%, the enzymolysis temperature is 45 DEG C, a pH value is 8.0, the enzyme addition amount is 8000U/g, and the enzymolysis time is 60min. The properties of polypeptide products are compared and analyzed, the relativemolecular mass of the products is mainly concentrated within a range of 0-2 kDa, good normal-temperature storage stability and in-vitro digestion stability are achieved, and a theoretical basis is provided for industrial production and practical application of the products.

The invention discloses a preparation method of soybean protein emulsion gel rich in zeaxanthin and lutein, belongs to the technical field of soybean protein processing, and aims to solve the technical problems of low antioxidant activity of soybean protein food and lack of a slow-release carrier embedding two bioactive molecules including zeaxanthin and lutein simultaneously at present. The method comprises the following steps: firstly, performing ultrahigh-pressure treatment on soybean protein isolate (SPI), then, carrying out enzymolysis, adding the zeaxanthin after enzymolysis, conductingreaction in a dark place under magnetic stirring, adding the lutein, and performing high-pressure microjet homogenization treatment to obtain an emulsion; and finally, conducting enzyme crosslinking reaction to obtain the soybean protein emulsion gel rich in the zeaxanthin and the lutein. The prepared soybean protein emulsion gel is rich in the zeaxanthin and the lutein, the zeaxanthin and the lutein have a synergetic effect, the free radical scavenging and antioxidant activity of the product are improved, and meanwhile, the emulsion gel has good external digestion slow-release effects on thezeaxanthin and the lutein.

The invention relates to a keratin degrading bacteria NJK4, belongs to the field of biological high technology. The bacterial strain NJK4 is classified and named as bacillus pumilus, and the preservation number is CGMCC (China General Microbiological Culture Collection Center) NO.3980. The NJK liquid culture is obtained by inoculating the bacterial strain in a seed medium and culturing for 24 hours in 120r/min at 37 DEG C. The bacterial strain is capable of degrading feather keratin in a feather fermentation medium, the degrading rate of the feather keratin is 85.76%, and the in vitro digestibility coefficient of the fermented feather powder is 94.73%. The keratin degrading bacteria NJK4 can be applied to the development and utilization of waste feather resources in poultry slaughtering, the waste feather is translated into a high-class protein feed source, the waste materials are recycled and the environment is protected, the sustainable development is promoted, and the keratin degrading bacteria NJK4 has a wide application prospect.

The invention discloses a liquid chromatography-mass spectrometry technology-based protein-polysaccharide complex digestibility analyzing method. The liquid chromatography-mass spectrometry technology-based protein-polysaccharide complex digestibility analyzing method comprises in vitro digesting protein solution and protein-polysaccharide complex solution in simulative gastric juice; performing denaturation treatment on digested proteins and digested protein-polysaccharide complexes, removing low-molecular-weight peptide fragments through an ultrafiltration pipe, and further completely hydrolyzing large-fragment polypeptides retained inside the ultrafiltration pipe through a second endo protease with clear enzyme-digesting points except pepsase to obtain a number of polypeptide fragments;detecting the composition and abundance of the polypeptide fragments through the liquid chromatography-mass spectrometry technology; according to the abundance of the polypeptides digested by the second endo protease and the pepsase, determining the digestibility of the pepsase; further, according to the high-abundance polypeptides in the two types of peptide fragments in the protein-polysaccharide complex group, deducting the binding sites of proteins and polysaccharides.

The invention provides a preparation method of standardized in vitro tumor micro-tissues, belonging to the technical field of biological medicines. The preparation method comprises the steps of dividing a solid tumor tissue into small blocks, and carrying out interception by virtue of a porous sieve according to the diameter size of the tumors, so as to obtain uniform-size tumor micro-tissues. The preparation method can be applied to the culture and drug evaluation of tumor tissues. The tumor tissues prepared by virtue of the preparation method are controllable in sizes and convenient to use and can be standardized for subsequent operation. According to the preparation method, the problem that the in vitro culture of the tumor tissues is difficult to be standardized is solved; and meanwhile, the used tumor tissues are not subjected to in vitro digestion and dispersion, so that the components and characters of the tumor tissues are preserved, and the effects of the tumor tissues are guaranteed.

The invention discloses a method for measuring the glycemic index of carbohydrate food in vitro, and belongs to the technical field of food detection. The method for measuring the glycemic index of carbohydrate food in vitro comprises the following steps of: (1) obtaining the reducing sugar release rate and digestibility of carbohydrate food to be measured; (2) obtaining related in-vitro digestion test parameters; (3) establishing a database for standard carbohydrate food with known GI values, and defining and establishing a function relationship between the glycemic index GI of a standard sample and the in-vitro digestion test parameters; and (4) carrying out an in-vitro digestion test on the carbohydrate food to be measured to obtain a plurality of related parameters of the in-vitro digestion test, and comparing the related parameters with the standard database to predict the glycemic index, namely the GI value. According to the relation between the in-vitro digestion parameter and the GI value obtained through the method, the linear correlation is 0.9 or above, and the prediction accuracy is higher.

The invention discloses a preparation method and application of a human endometrial stem cell compound repair factor. The preparation method specifically includes the following steps that a human endometrial stem cell is separated from human endometrial tissue; in-vitro digestion separation and expanded culture is performed on the human endometrial stem cell to obtain a high-quality human endometrial stem cell; industrialized amplification culture is performed on the high-quality human endometrial stem cell, and stem cell culture supernatants of the P3-P6 generations are collected; the stem cell culture supernatants are subjected to concentration, protein content determination and quality inspection to obtain a human endometrial stem cell concentration factor; the human endometrial stem cell concentration factor is mixed with a freeze-drying protective agent, and then freeze-drying is conducted to obtain human endometrial stem cell freeze-dried powder; and the human endometrial stem cell freeze-dried powder is mixed with a solvent to obtain the human endometrial stem cell compound repair factor. The repair factor has a remarkable treatment effect, a patient is free of pain, an operation and a surgery are not required, no side effect is caused, and the factor is safe and efficient.

The invention discloses a method for preparing a paper mulberry compound feed through synergistic fermentation of bacteria and enzymes and the compound feed prepared through the method. The method comprises the steps of (1) preparing fermentation raw materials; (2) preparing an activated culture medium; (3) activating strains and preparing a fermentation seed solution, inoculating saccharomyces cerevisiae and lactobacillus plantarum into the activated culture medium, conducting mixing according to a volume ratio of 2: 1, adding acid protease, conducting uniform mixing to obtain the fermentation seed solution, and then performing inoculating; and (4) bagging for fermenting, wherein the fermentation seed solution is put into a breathing bag and fermented for 3-5 days. According to the invention, the content of crude protein, small peptide, probiotics, organic acid and flavone in the paper mulberry compound feed can be remarkably improved, the total antioxidant capacity of the feed is enhanced, the content of tannin and crude fiber is effectively reduced, the in-vitro digestibility of pigs taking the paper mulberry compound feed is improved, and the application prospect is relativelygood.