526 results about "Oxidative damage" patented technology

The invention discloses an application of soluble lignin as a synergist for ethanol fermentation and / or improvement of stress resistance of yeast under a fermentation environment stress condition, the soluble lignin is added into an ethanol fermentation system, and the problems of pH instability, oxidative damage, heavy metal inhibition and the like in ethanol fermentation can be synchronously solved; the survival rate of yeast and the yield of ethanol are remarkably improved, the process steps are simplified, the cost is reduced, the method is suitable for ethanol industrial production of agricultural and forestry wastes and other raw materials, and a green and practical technical path is provided for efficient utilization of all components of lignocellulose. In addition, the soluble lignin disclosed by the invention can also be recycled, can still keep a relatively high synergistic effect after being recycled for multiple times, and has a wide application prospect in the field of bioethanol fermentation.

The invention discloses a compound composition with a multi-target heart protection function as well as a preparation method and application of the compound composition. The composition is composed of a basic functional oil phase, a core antioxidant / anti-inflammatory phase, a myocardial nutrition and regulation phase and a bioavailability promotion phase in a synergistic manner, and is integrated into a composite cardiac oligopeptide and microencapsulated particle key component substance through a specific enzymolysis and microencapsulation embedding process system. The invention aims to solve the technical problems of single target spot, insufficient synergistic effect of all components, low bioavailability of active components and poor stability of the existing heart protection product, and provides a stable and easily-absorbed composite composition which can realize synergistic effect from multiple channels at the same time. Technical effect verification shows that under the condition of equal-dose sample feeding, the composition can remarkably improve the bioavailability of functional components and shows excellent myocardial cell oxidative damage resistance and myocardial ischemia improvement activity in cell and animal models, the effect is remarkably superior to that of independent use or simple physical mixing of all the components, and the composition is suitable for clinical application. And the substantial progress of synergistic interaction is proved. The composition can be used for developing various medicines, health foods and functional foods beneficial to heart health.

The invention relates to preparation of high-stability mascarpone cheese and application of the mascarpone cheese in baking, and belongs to the technical field of cheese preparation. The glutamine transaminase is combined with a citric acid-sodium citrate system, so that the excessive denaturation of protein is reduced, and the texture and flavor of the cheese are improved. Trehalose and xanthan gum are added for locking water and resisting freezing, and an antioxidant is combined for use, so that the freeze-thaw stability and oxidation resistance of the cheese are improved, the cheese is protected from texture change and oxidative damage in the freezing and unfreezing processes, and excellent texture and flavor can still be kept after multiple times of circulation. Arabic gum is modified through octenyl succinic anhydride, amphipathy is obtained, whey separation is prevented, whey loss is reduced, and the cheese taste is improved.

The present invention relates to the field of biomedical materials, particularly to a novel composite collagen material for wound repair, and more specifically to a method for preparing a novel composite collagen material comprising recombinant humanized collagen type 21 (ColpepA1 21) and its use in wound repair. The present invention utilizes ColpepA1 21 to significantly promote key biological reactions in the wound healing process, including accelerating cell migration, enhancing skin hydration and barrier function, and improving the stability and elasticity of skin structure. The resulting novel composite collagen material effectively promotes wound healing and cell regeneration, alleviating oxidative damage.

The invention belongs to the field of corn disease prevention, relates to a novel small peptide, provides a small peptide NCRP246 and application thereof in improvement of corn southern leaf blight resistance, and provides feasibility for plant disease resistance by using non-classical peptides. A corn southern leaf blight resistance identification experiment proves that NCRP246 can significantly improve the resistance of corn to southern leaf blight, and further researches that the NCRP246 reduces oxidative damage of pathogenic bacteria infection of the southern leaf blight to the corn by reducing H2O2 accumulation so as to mediate the resistance of the corn to the southern leaf blight; the analysis from the molecular perspective proves that the NCRP246 can induce the expression of defense related genes.

The invention discloses a cold response PaIBH1 protein and application of a coding gene thereof in enhancing cold stress resistance of plants. The cold response PaIBH1 protein is a protein PaIBH1 with an amino acid sequence as shown in SEQ ID NO: 2. Experiments prove that the gene for coding the protein PaIBH1, namely the gene PaIBH1, is overexpressed in wild type arabidopsis thaliana, so that the cold resistance of the arabidopsis thaliana can be improved; the improvement of the cold resistance shows that after cold treatment, the fresh weight of the overground part is increased, the wilting rate is reduced, the leaf membrane damage and electrolyte leakage are reduced, the photosynthetic ability is improved, the membrane lipid peroxidation damage is relieved, the active oxygen scavenging ability is enhanced and / or the active oxygen accumulation in the plant body is reduced. Therefore, the protein PaIBH1 can improve the cold resistance of the plants. The method has a very wide application prospect in the aspect of cold-resistant genetic improvement of crops or pasture.

The present invention discloses a strain of Lactobacillus paracasei that simultaneously activates immune regulation and antioxidant pathways to alleviate vaginitis, belonging to the field of microbial technology. The present invention screened and obtained a strain of Lactobacillus paracasei CCFM1316, which has the effect of repairing related symptoms such as immune disorders and oxidative damage caused by vaginitis, specifically embodied in: reducing cellular NF-κB mRNA expression and cell supernatant IL-1β content, improving mouse vaginal immune response, enhancing mouse vaginal antioxidant capacity, improving mouse vaginal pathological manifestations and reducing pathogenic bacteria load. It reduces the mouse vaginal Gardnerella load and improves mouse vaginal pathological manifestations; therefore, Lactobacillus paracasei CCFM1316 has great application prospects in products that improve and repair immune disorders and oxidative damage problems caused by vaginitis.

The invention relates to a plant lactobacillus with effects of dispelling effects of alcohol, protecting the liver and restoring consciousness and application of the plant lactobacillus. The plant lactobacillus is a plant lactobacillus BGI-J9 strain, and the preservation number of the plant lactobacillus is CCTCC NO: M 20242630. The invention further discloses a preparation method of the plant lactobacillus with the effects of dispelling effects of alcohol, protecting the liver and restoring consciousness and application of the plant lactobacillus with the effects of dispelling effects of alcohol, protecting the liver and restoring consciousness. The strain has excellent tolerance to gastric acid, intestinal juice and cholate in a gastrointestinal tract system, can survive in the gastrointestinal tract, and provides a basis for continuously playing a probiotic effect; the compound has excellent inhibition capability on common intestinal pathogens; free radicals can be removed, and oxidative damage to the body is reduced; good alcohol metabolism enzyme synthesis capability and alcohol metabolism promoting potential are realized; the strain also has an excellent improvement effect on alcohol-damaged mice, specifically, the metabolism of ethanol and acetaldehyde in a body is accelerated, the occurrence time of drunkenness is obviously delayed, and the sobering time is shortened; intestinal injury and systemic inflammation caused by alcohol are improved; liver oxidative stress caused by alcohol is improved, and the occurrence and development process of alcoholic fatty liver is delayed; and cognitive function impairment caused by alcohol is improved.

The invention discloses a method for improving in-vivo and in-vitro antioxidant activity of pomegranate peel polyphenol extract through combined enzymolysis of tannase and beta-glucosidase, and relates to the technical field of food science and biology. The pomegranate peel polyphenol extract provided by the invention is obtained from pomegranate peel powder through solvent extraction. According to the present invention, tannase and beta-glucosidase are adopted to perform single or combined enzymolysis on the pomegranate peel polyphenol extract, and the determination on the in vitro antioxidant activity of the pomegranate peel polyphenol extract shows that the antioxidant activities of DPPH and ABTS after the combined enzymolysis are improved by 29.84% and 29.30% compared with the antioxidant activities of the untreated polyphenol extract; the UPLC-ESI-QTOF-MS is used for identifying and analyzing the components of the enzymatic hydrolysate, the content of macromolecular ellagic tannin is obviously reduced, and the content of micromolecular ellagic acid and gallic acid is increased. The enzymolysis polyphenol is applied to D-galactose induced oxidative stress mice, and the result shows that the oxidative damage relieving effect of the enzymolysis polyphenol on the mice is better than that of untreated polyphenol.

The invention relates to a plant composition as well as a preparation method and application thereof, and belongs to the technical field of health food. The plant composition is prepared from the following components in parts by mass: 5 to 30 parts of fructus gardeniae, 5 to 30 parts of fructus rubi and 5 to 30 parts of fructus lycii. The plant composition can effectively relieve liver oxidative stress and inflammation conditions, relieve and / or improve alcoholic liver injury, protect liver cells from oxidative injury, assist a body in resisting oxygen free radical invasion and maintain the health state of the body, does not affect the blood sugar level, and has the advantages of being reasonable in compatibility, good in quality, safe and effective.

The invention provides a chitosan-iron nanoparticle leaf surface resistance and control agent as well as a preparation method and application thereof, and belongs to the technical field of reduction of heavy metal pollution of crops. The preparation method comprises the following steps: dissolving chitosan in an organic solvent to obtain a chitosan solution, mixing the chitosan solution with ferrous sulfate, adding a sodium tripolyphosphate solution for crosslinking and stirring to obtain a solution containing precipitates, centrifuging, and collecting the precipitates to obtain the chitosan / ferrous sulfate composite material. The TPP and amino groups of the chitosan form ionic crosslinking through triphosphate groups, and Fe < 2 + > is successfully loaded on the surfaces of the chitosan nanoparticles. By complexing chitosan and Fe < 2 + >, the crystallinity of the material is reduced, and the adsorption activity of the amorphous structure is enhanced. Pot experiments show that by spraying the chitosan-iron nanoparticle leaf surface resistance and control agent on leaf surfaces, heavy metals of crops can be remarkably reduced, the antioxidant enzyme activity of plant tissues is improved, active oxygen is effectively removed, oxidative damage is relieved, and therefore plant growth is promoted, and the toxic effect of heavy metal stress on the crops is relieved.

A circadian rhythm-based time-sharing repair formula and use thereof. A day composition focuses on anti-oxidation, stress resistance and energy metabolism to resist oxidative damage and enhance day vitality and provide long-lasting antioxidation protection. A night composition focuses on DNA repair, anti-inflammation and nerve relaxation to promote cell regeneration and repair and continuously support night repair. The composition of the day composition and the night composition designed according to the circadian rhythm of human metabolism causes the corresponding activities to take effect at the best time, and components are designed to cooperate with each other according to different physiological needs during the day / night, which can greatly improve the anti-aging effect.

The invention discloses a plant lactobacillus with light aging resistance and an application thereof. The preservation number of the plant lactobacillus cj001 disclosed by the invention is CGMCC (China General Microbiological Culture Collection Center) No.35419. The fermentation supernatant of the plant lactobacillus cj001 shows good anti-aging activity and in-vitro antioxidant activity, and the growth ability of HaCaT cells is promoted. After the combined fermentation product of the plant lactobacillus cj001 and the lactobacillus paracasei Grx701 is subjected to ultraviolet radiation, the proliferation of HaCaT cells can be promoted, the endogenous antioxidant capacity of human skin cells can be enhanced, the photooxidation damage can be effectively relieved, and the combined fermentation product has a wide application value in the field of preparation of products with antioxidant, anti-aging, anti-ultraviolet damage, anti-photoaging and the like.

The invention discloses a plant source leaf surface resistance and control agent for efficiently reducing the cadmium content of wheat and a preparation method thereof. According to the invention, S-allyl-L-cysteine is used as an important component of the foliar blocking and controlling agent, so that the bioavailability of cadmium ions is effectively reduced, and the absorption and transport of cadmium in plants are reduced, thereby reducing the cadmium content in wheat grains. Meanwhile, S-allyl-L-cysteine has relatively strong antioxidant capacity, so that free radicals in the plant body can be removed, and cells are protected from oxidative damage. As a plant growth regulator, S-allyl-L-cysteine can improve nutrient absorption and utilization of plants and promote photosynthesis and energy metabolism of the plants, so that the yield and quality of wheat are improved. The S-allyl-L-cysteine can activate a defense mechanism in a plant body, enhance the resistance of the plant to environmental stress, including the resistance to heavy metal pollution, and improve the overall health and yield of wheat.

The invention discloses a ganoderma lucidum lipid exosome containing a liver protection component and a preparation method and application thereof.The preparation method comprises the steps that the liver protection component is wrapped with a coarsely extracted ganoderma lucidum exosome, then the liver protection component is wrapped with lipidosome, and therefore a lipidosome-exosome-liver protection component three-layer structure is formed from outside to inside; in the three-layer structure, the outer layer liposome can protect the storage of the liver protection component and can improve the transmembrane transport efficiency, the middle layer exosome serves as a carrier and can reach a designated position to be released, and the inner layer contains the liver protection component and can improve the transmembrane transport efficiency. Cell cycle arrest can be prevented, antioxidant enzyme activity can be improved, cell membranes can be protected from oxidative damage, and redox steady state can be maintained to relieve cell aging. The prepared ganoderma lucidum lipid exosome containing the liver protection component realizes slow release synergy through a three-layer structure, and the action time of the active component is remarkably prolonged.

The invention relates to the technical field of microorganisms, in particular to lactobacillus paracasei DT33 and application of the lactobacillus paracasei DT33 in preparation of products with microplastic adsorption, removal and defecation promotion functions. The lactobacillus paracasei DT33 disclosed by the invention can be used for producing various SCFAs at high yield, has better acid-resistant and cholate-resistant capabilities and safety, and can be developed into edible probiotics; the strain has the function of promoting defecation, and can improve intestinal health and immune function; in addition, the strain can adsorb micro-plastics, accelerate discharge of the micro-plastics, reduce micro-plastic residues in intestinal tracts, reduce oxidative damage and inflammatory response caused by accumulation of the micro-plastics, and provide great benefits for intestinal health of human bodies and animals.

The invention discloses an algin composite membrane which is prepared by the following steps: adding 0.8-1.2 g of algin, 0.8-1.2 g of hydroxypropyl methyl cellulose, 0.8-1.2 mL of glycerol, 0.4-0.6 g of titanium dioxide and 0.8-1.2 g of polylysine into water, uniformly mixing, fixing the volume, putting into a container, drying, immersing into a CaCl2 solution for crosslinking treatment, and drying, thereby obtaining the algin composite membrane. The algin composite film can be used as or used for preparing a food preservative film. The algin composite film disclosed by the invention realizes good balance between strength and ductility, has good antioxidant capacity and remarkable antibacterial effect, and can effectively enhance the antioxidant defense capacity of the cape gooseberries, reduce oxidative damage, prolong the storage period and improve the fresh-keeping effect of the cape gooseberries. According to the method, the economic value of the sargassum is favorably improved, and powerful support is provided for sustainable development of the food industry.

The invention discloses application of polydatin in preparation of a medicine for relieving hepatotoxicity caused by zearalenone, and belongs to the technical field of biological medicine. The invention reveals that polydatin inhibits hepatotoxicity caused by zearalenone through targeted xanthine oxidase for the first time, so that the toxicity of zearalenone to an organism is relieved. Polydatin can be directly combined with xanthine oxidase to inhibit the catalytic activity of xanthine oxidase, so that the oxidative stress injury of the liver after ZEA exposure is reduced, meanwhile, the content of malondialdehyde (MDA) in the liver can be remarkably reduced, the activity of superoxide dismutase (SOD) is improved, the liver oxidation-antioxidant balance is recovered, and liver cells are protected from oxidative injury of ZEA. The invention provides a new scientific basis and development direction for application of polydatin in the fields of mycotoxin detoxification, oxidation resistance, liver protection and the like.

The invention provides an edible coating fresh-keeping liquid suitable for low-temperature refrigeration of harvested tropical fruits and a storage and fresh-keeping method. The low-temperature cold storage edible film coating fresh-keeping liquid is soybean oil. When bananas or mangoes are coated with the edible coating liquid for low-temperature refrigeration, the occurrence of fruits under low-temperature refrigeration can be effectively inhibited, and the sensory quality and shelf life of the fruits can be maintained. Bananas or mangoes are subjected to soybean oil coating treatment, so that the relative conductivity of fruit tissues can be effectively reduced, and the integrity of fruit cell membranes is maintained; according to the present invention, the production of H2O2, O2 <-> and MDA can be significantly reduced, the activity of POD can be inhibited, and the activity of PPO, SOD and CAT can be enhanced so as to activate the anti-oxidation defense system of fruits, reduce the oxidative damage caused by cold injury, and enhance the accumulation of osmotic regulation substances; the content of antioxidant carotenoid can be increased, so that the stress resistance of the fruits is improved, and the cold injury of the fruits in the low-temperature storage process is reduced.

The invention belongs to the technical field of mesenchymal stem cell exosome compositions, and discloses a preparation method and application of a mesenchymal stem cell exosome composition. The mesenchymal stem cell exosome composition is prepared from a mesenchymal stem cell exosome, a hyaluronic acid-arginine grafted copolymer, acetyl tetrapeptide-5, resveratrol, mannose, polyglycerol-8 octoate and a buffer solution. Arginine residues contained in the hyaluronic acid-arginine graft copolymer in the composition can be specifically combined with integrin receptors (such as alpha v beta 3) highly expressed by fibroblasts at the wrinkle part, so that the exosome can actively anchor the wrinkle part, can be accurately and directionally enriched at the wrinkle part, and is high in utilization rate and high in anti-wrinkle efficiency. The composition constructs a three-dimensional anti-wrinkle network of mesenchymal stem cell exosome, acetyl tetrapeptide-5 and resveratrol, skin collagen degradation and oxidative damage are effectively restrained, and generation of skin wrinkles is blocked through multiple channels.

The invention discloses an application of costunolide in preparation of a medicine for treating and / or preventing a non-alcoholic fatty liver disease. It is found that costunolide can activate an Nrf2-ARE signal channel of a body, liver cell lipid metabolism abnormality is effectively improved from the molecular level, and meanwhile the pathological influence of oxidative damage on liver tissue is remarkably relieved. Experimental data show that the compound has a remarkable intervention effect on NAFLD, a scientific basis is provided for development of a novel liver disease treatment agent due to the unique dual regulation and control mechanism of the compound, particularly, the compound shows an important development prospect in the field of clinical intervention of metabolism-related liver injury, and an innovative solution is provided for NAFLD lacking a special-effect therapy at present.

The invention discloses a lactobacillus mucus fermentation strain. The microbial preservation number of the lactobacillus mucus fermentation strain is CCTCC (China Center for Type Culture Collection) NO: M 20252262. The strain can inhibit enterotoxigenic escherichia coli, and can treat or slow down diarrhea, intestinal oxidative damage, intestinal inflammation damage, intestinal morphological damage, intestinal barrier function damage and intestinal flora disorder caused by the enterotoxigenic escherichia coli. The strain is a probiotic with a clinical application prospect.

The invention provides a cassava low-temperature-resistant MeSR34b gene. The CDS sequence of the cassava low-temperature-resistant MeSR34b gene is as shown in SEQ ID NO: 1. The cassava low-temperature-resistant MeSR34b gene is cloned from cassava for the first time, the expression of the MeSR34b gene in the cassava is inhibited under low-temperature stress, and research shows that the gene can remarkably improve the low-temperature resistance of the cassava, increase the malondialdehyde content, the proline cumulant and the like in the cassava, reduce oxidative damage of cells, yellow newborn leaves of the cassava and improve the yield of the cassava. The expression of various protein genes is regulated and controlled. The invention provides a new candidate gene for research on improvement of low temperature resistance, oxidative damage resistance and the like of plants.

The invention belongs to the technical field of preparation of peptides, and particularly relates to camel placenta hydrolysate as well as a preparation method and application thereof. According to the preparation method of the camel placenta hydrolysate and the preparation method of the camel placenta hydrolysate provided by the invention, the camel placenta hydrolysate has remarkable scavenging activity on DPPH, ABTS, hydroxyl free radicals and iron ions, so that the antioxidant activity is exerted; in a fruit fly acute oxidative damage model, the camel placenta hydrolysate can prolong the survival time of fruit flies in an oxidative stress environment; in a normal fruit fly model, the camel placenta hydrolysate can prolong the life of normal aging fruit flies, improve the action ability of the aging fruit flies and play an anti-aging role by improving the activity of in-vivo antioxidant enzymes such as total superoxide dismutase, copper-zinc superoxide dismutase and catalase and reducing the malondialdehyde level on the premise of not reducing the food intake of the fruit flies. The camel placenta hydrolysate can be used as an ideal auxiliary antioxidant and anti-aging medicine and health food raw material.

The invention discloses a preparation method of crocodile liver peptide for improving liver injury, and relates to the technical field of bioactive peptide extraction, and the preparation method comprises the following steps: crocodile liver pretreatment: cutting fresh crocodile liver into blocks, mixing with deionized water, homogenizing, and adding a zirconium phosphate molecular sieve to obtain crocodile liver homogenate; enzymatic hydrolysis reaction: adjusting the pH value of the homogenate, and adding a compound enzyme preparation for enzymatic hydrolysis; carrying out enzyme deactivation treatment, namely heating, cooling, centrifuging and taking supernate; performing ultrafiltration separation, namely filtering the supernate through an ultrafiltration membrane, and collecting a small molecule peptide solution; purifying and refining: purifying through sephadex column chromatography, and freeze-drying to obtain a crocodile liver peptide product; a double-particle-size zirconium phosphate molecular sieve is constructed to cooperate with a compound enzyme preparation for enzymolysis, electron transfer is enhanced by combining phosphorylation modification, the defects of metal inhibition enzyme activity, insufficient concealed peptide fragment cutting and oxidative damage are overcome, meanwhile, the application of the crocodile liver peptide in the aspect of improving the liver function is researched, and the crocodile liver peptide has a good application prospect. And a new choice is provided for prevention and treatment of liver diseases and liver health care.

The invention belongs to the technical field of microorganisms and fermentation engineering, and particularly relates to fermented lactobacillus mucus with an anti-aging function and application of the fermented lactobacillus mucus. The strain is preserved in Guangdong Microbial Culture Collection Center on August 27, 2025, and the preservation number is GDMCC No: 66877. Experimental results show that the bacterium has excellent oxidation resistance, can relieve oxidative damage, delay senescence and inhibit senescence-related gene expression, shows the capabilities of improving memory reproduction capability decline caused by senescence, improving body anti-inflammatory capability and improving intestinal flora imbalance induced by senescence, and can regulate fat factor level and improve energy metabolism, so that the function of resisting senescence is achieved. And the polypeptide shows the potential of resisting fat deposition and protecting liver functions. Therefore, the strain can be used for developing products with multiple beneficial functions of delaying senescence, contributing to resisting oxidation, assisting in improving memory, contributing to regulating intestinal flora and the like, has the advantages of high safety, strong gastrointestinal tract tolerance and good colonization ability, and has a very good application value.

The invention discloses a tumor targeting boron-containing Fe3O4-based nano-enzyme and a preparation method and application thereof, and belongs to the technical field of tumor treatment.The tumor targeting boron-containing Fe3O4-based nano-enzyme takes boron-10 doped Fe3O4 nano-enzyme as a boron-containing drug group and an enzyme activity center, and the surface of the tumor targeting boron-containing Fe3O4-based nano-enzyme is modified with a targeting group; the targeting group is chitosan-folic acid-polyethylene glycol. The tumor targeting boron-containing Fe3O4-based nano-enzyme has relatively strong selective enrichment capacity on tumor cells such as melanoma, shows good biocompatibility and low toxicity, and has relatively strong apoptosis induction and killing effects on the melanoma cells in boron neutron capture therapy; meanwhile, active oxygen free radicals can be generated in boron neutron capture therapy to generate an oxidative damage effect.

The invention belongs to the technical field of fermentation and metagen preparations, and particularly relates to application of bifidobacterium breve metagen in the aspects of scavenging free radicals and relieving oxidative aging. According to the present invention, the oxidative free radical scavenging experiment results show that the bifidobacterium breve NKU BB 1-2 metagen has good oxidative free radical scavenging ability, and has good scavenging ability on hydroxyl free radicals, superoxide anions and DPPH free radicals; meanwhile, through component analysis, it is found that the bifidobacterium breve NKU BB 1-2 metagen contains various antioxidant and anti-aging bioactive substances such as flavonoids, indoles, amino acids, bile acids and ceramides; a cell model experiment verifies that the bifidobacterium breve NKU BB 1-2 metagen can obviously relieve oxidative damage to the cells and improve the oxidation resistance of the cells, so that oxidative aging is relieved.

The invention discloses a complete feed suitable for sows in a perinatal period and a preparation method of the complete feed in the technical field of animal nutrition and feed science, and relates to a beta-glucan sulfated-chitosan conjugate and a nano-embedded quercetin-medium-chain fatty glyceride compound, and application of the beta-glucan sulfated-chitosan conjugate and the nano-embedded quercetin-medium-chain fatty glyceride compound in the complete feed. Wherein the beta-glucan sulfated-chitosan conjugate is formed by carrying out sulfated modification on beta-glucan through chlorosulfonic acid and then carrying out covalent coupling on the modified beta-glucan and chitosan under the conditions of a specific condensing agent and pH (Potential of Hydrogen). The complete feed contains the energy raw material, the protein raw material, the functional additive and the two modified compounds, and is prepared through the processes of step-by-step crushing, mixing and granulation, the complete cycle regulation of relieving constipation, promoting ingestion, reducing oxidative damage and improving lactation performance is finally achieved, and the breeding efficiency of sows and the health level of piglets are remarkably improved.

The invention discloses a preparation method and application of a response type cationized two-dimensional nano catalytic transfection agent, and belongs to the field of biology. According to the transfection agent disclosed by the invention, two-dimensional MXene (such as niobium carbide) is taken as a matrix, and the surface of the matrix is sequentially modified with a multi-amino cationic polymer (such as dendritic polyethyleneimine) and aldehyde group polyethylene glycol (CHO-PEG-CHO), so that PNb2C (at) PEG with pH responsiveness is formed. The preparation method comprises the steps of Nb2C nanosheet stripping, PEI cationization, PEG shielding modification and the like. Material characterization shows that the potential of the transfection agent is-12.5 mV (shielding positive charges) when the pH value is 7.4, the potential of the transfection agent is converted into + 14.0 mV (responding to a tumor acidic microenvironment) when the pH value is 6.5, and the transfection agent has the capability of catalyzing decomposition of active oxygen and can protect cells from oxidative damage. Compared with the traditional cationic liposome, the transfection efficiency is equivalent, but the toxicity is obviously reduced, the raw material cost is low, the gene load is high, and the cationic liposome is suitable for the field of gene delivery.