168 results about "Intestinal cell" patented technology

The invention belongs to the technical field of biology, and discloses a reagent combination or kit for constructing intestinal organs and application of the reagent combination or kit. According to the reagent combination or the kit, intestinal organs can be obtained from cell-derived epithelial cells obtained from a donor in a non-invasive manner, and the obtained intestinal organs can be cryopreserved and recovered and can be amplified in vitro for a long time; transcriptome characteristics are similar to those of real human small intestine tissues, and typical marker genes of various small intestine pedigree cell types are highly expressed; compared with intestinal organs obtained through induction of pluripotent stem cells, the intestinal organs have more intestinal pedigree characteristics, and the intestinal function development is more mature; after being promoted to be mature, the intestinal organ also highly expresses genes related to drug absorption and metabolism, has drug absorption capability similar to that of an immortalized intestinal cell line, but more prominently shows intestinal cell lineage characteristics, is closer to an intestinal environment in a real human body, and can be used for screening intestinal disease drugs; the intestinal barrier function is realized.

The invention relates to a bifidobacterium animalis subsp. Lactis YYSJ001 with a blood sugar reducing effect and application of the bifidobacterium animalis subsp. Lactis YYSJ001. The classification name of the strain is bifidobacterium animalis subsp. Lactis, and the preservation number is CGMCC (China General Microbiological Culture Collection Center) No.33471. The invention further relates to a preparation method of the bifidobacterium animalis subsp. Lactis YYSJ001. The bacterial strain has good artificial gastric juice resistance, artificial intestinal juice resistance and intestinal tract adhesion ability, has an inhibition effect on numerous pathogenic bacteria such as escherichia coli, staphylococcus aureus, salmonella, klebsiella pneumoniae and quail chicken enterococcus, and can stimulate intestinal cells to generate glucagon-like peptide-1, so that the bacterial strain can be applied to preparation of various pathogenic bacteria. Diseases of diabetic mice can be effectively improved, and the compound can be used for preparing products for preventing and treating diabetes or assisting in reducing blood sugar.

The invention provides a composition capable of penetrating an intestinal barrier by oral administration. The composition contains a carrier or an auxiliary material of a targeted Microflod cell Dectin-1 receptor, and one or / and a plurality of medicinal components / components, wherein the carrier or the auxiliary material of the target Microflood cell Dectin-1 receptor is beta-glucan, and the carrier or the auxiliary material of the target Microflood cell Dectin-1 receptor is beta-glucan. The effective components / components are traditional Chinese medicine effective components / components, or / and probiotics, or / and chemical medicine components, or / and biological medicines. The invention relates to a composition capable of realizing oral administration and penetrating through an intestinal barrier, which is based on the discovery of the inventor that the composition reaches colon through gastrointestinal tracts, targets colon Microflood cells, is taken by the Microflood cells, penetrates through the intestinal barrier and enters immune tissue Colonic Patches of a colon submucosa. Based on the research, the composition disclosed by the invention can be used for treating various diseases, such as ulcerative colitis, Crohn's disease, colon cancer, rheumatoid arthritis or bacterial pneumonia after being orally taken and absorbed by rectum.

The invention discloses an inflammatory bowel disease model, a construction method and application thereof and a drug evaluation method based on the inflammatory bowel disease model, and belongs to the technical field of inflammatory bowel disease model construction. A highly bionic intestinal crypt-villus three-dimensional structure is formed based on self-organization of an intestinal cell line C2BBe1, the intestinal crypt-villus three-dimensional structure and a DMEM complete medium containing dextran sulfate sodium are added into an upper chamber of a double-layer culture chamber Transwell, the DMEM complete medium is added into a lower chamber of the double-layer culture chamber Transwell, culture is performed for 2 days, and the inflammatory bowel disease model is obtained. The method takes effect quickly and is highly simulated, the obtained model can simulate the space-time dynamic development process of intestinal inflammation molecular characteristics, and the natural recovery model and the drug treatment model constructed based on the model can provide a brand new platform for researching an inflammation regression mechanism and a drug intervention effect.

The invention relates to the technical field of microorganisms, in particular to lactobacillus rhamnosus HZBX-05 and application thereof.The lactobacillus rhamnosus HZBX-05 is sent to the China General Microbiological Culture Collection Center on July 27th, 2023 to be preserved in the China General Microbiological Culture Collection Center, the preservation number of the lactobacillus rhamnosus HZBX-05 is CGMCC NO.987, and the preservation number of the lactobacillus rhamnosus HZBX-05 is CGMCC NO.989. The lactobacillus rhamnosus HZBX-05 is CGMCC NO.989. The lactobacillus rhamnosus HZBX-05 is CGMCC NO.989. The preservation number is CGMCC (China General Microbiological Culture Collection Center) NO.28035, and the address is Institute of Microbiology, Chinese Academy of Sciences, No.3, No.1 Yard, West Beichen Road, Chaoyang District, Beijing; the separated Lactobacillus rhamnosus HZBX-05 is continuously treated for 7 hours in a simulated gastric acid cholate environment, and the result shows that the HZBX-05 still has high survival rate, has the capability of being highly adsorbed to intestinal cells Caco-2 cells, has the capability of inhibiting various pathogenic bacteria, has immunoregulation and anti-inflammation effects, has the effect of resisting helicobacter pylori, and can be used for preparing an anti-inflammatory drug. The symptoms of female vaginitis can be improved.

The invention relates to the technical field of microorganisms, in particular to compound probiotics capable of degrading indole and preventing or relieving nephropathy and application of the compound probiotics. The compound probiotics comprise bifidobacterium animalis subsp. Lactis YYS-J9 with the preservation number of CGMCC (China General Microbiological Culture Collection Center) NO.28185 and bifidobacterium longum subsp. Longum YYS-BSM8 with the preservation number of CGMCC NO.28611. The invention further discloses a preparation method of the compound probiotics. Compared with the use of a single YYS-J9 strain or YYS-BSM8 strain, the two strains have synergistic effects after being compounded, the viable count is remarkably increased after mixed culture, the inhibition effect on pathogenic enterobacteria and the adhesion to intestinal cells are remarkably enhanced, the degradation capacity on indole and oxalic acid is higher, the proliferation and phagocytic activity of macrophages is remarkably improved, and the application range of the YYS-J9 strain and the YYS-BSM8 strain is widened. And when being applied to food, health-care products or medicines, the exopolysaccharide can be used for effectively preventing or improving nephropathy and kidney stone, regulating intestinal health and improving intestinal immunity.

The invention discloses a prebiotic-loaded intestinal targeting exosome and a preparation method and application thereof.The preparation method comprises the steps that firstly, plasmids containing intestinal cell targeting peptide sequences are constructed through a gene editing technology, the plasmids are transfected and introduced into cells, the transfected cells are screened with antibiotics, and cell strains stably expressing intestinal cell targeting peptides are obtained; then culturing and adding prebiotics, and continuously culturing to enable the cells to take in the prebiotics and release the exosomes loaded with the prebiotics; and finally, collecting cell culture supernate, and centrifuging and resuspending for multiple times under a low-temperature condition to obtain the prebiotics-loaded intestinal targeting exosome. According to the preparation method, extraction of the exosome, loading of the prebiotics and an intestinal targeting modification process are optimized, so that the prepared intestinal targeting exosome loaded with the prebiotics can be used for remarkably improving the loading efficiency and intestinal targeting of the prebiotics and enhancing the stability of the exosome in gastrointestinal tracts; therefore, the delivery efficiency and the treatment effect of the prebiotics in the intestinal tract are improved.

Provided are a substance and method for improving intestinal health and homeostasis, and the nutrition and development of a subject. The substance is an odd carbon fatty acid. Specifically, provided is the use of an odd carbon fatty acid in the preparation of a preparation or drug for increasing the protein expression abundance of related tight junction proteins of a subject, reducing the content of a corticotropin-releasing hormone in the intestinal tissue of a subject, improving or enhancing the intestinal mechanical barrier of a subject, maintaining the intestinal immune homeostasis of a subject, promoting the intestinal development of a subject, maintaining the energy homeostasis in intestinal cells of a subject, improving intestinal energy metabolism, promoting the development and metabolism of muscle tissue in a subject, promoting the development and metabolism of adipose tissue in a subject, reducing allergic reactions of the body and the intestinal tract of a subject, reducing the insulin resistance in a pregnant subject, controlling the blood glucose level in a pregnant subject, preventing gestational diabetes mellitus, preventing or improving intrahepatic cholestasis in a pregnant subject, preventing or treating diseases caused by Helicobacter pylori bacteria in a subject, etc.

The invention belongs to the field of functional substance research, and particularly relates to a nutritional composition for promoting absorption of fatty acid and mineral substances and application. The nutritional composition provided by the invention comprises necessary active ingredients shown as the following (I) and (II): (I) 1, 3-dioleic acid-2-palmitic acid triglyceride; (II) a milk fat globule membrane, and / or, 2 '-fucosyllactose; moreover, in the nutritional composition, the mass ratio of the necessary active component shown in (I) to the necessary active component shown in (II) is (5-10): (0.5-10). The combination of OPO and MFGM and / or 2 '-FL provided by the invention can be beneficial to promoting the absorption of the body to fatty acids and mineral substances, and especially can be beneficial to promoting the transmembrane transport capability of intestinal cells of the body to fatty acids and mineral substances, so that the absorption efficiency is improved.

The invention relates to the technical field of pharmaceutical preparations, and particularly provides colon-targeted pH-responsive nano-liposome and application thereof in improving oral bioavailability of saponin. Aiming at the problems of gastric acid damage, small intestine metabolism inactivation and low colon absorption efficiency during oral delivery of saponin, a three-layer core-shell structure design is adopted, wherein an inner core is composed of a saponin-phospholipid crystal compound; the middle layer is a chitosan-PEG bimolecular layer, and pH response release is realized in a colon environment with pH of 7.4; and the outer layer is modified with a folic acid-PE conjugate to enhance colon cell targeted recognition. The uniform nanoparticles with the particle size of 80 + / -5 nm are prepared by combining a gradient pH drug loading method with a microfluidic focusing technology. According to the preparation, the saponin bioavailability (AUC0-12 reaches 43.31 h. Microgram / mL) is remarkably improved, and the colon targeting property (the cell uptake rate is 52.9%) is enhanced. The innovativeness is that the gastrointestinal segmented protection and accurate colon release are synergistically realized through a multi-layer functional design, and the solubilization-permeation paradox of the traditional delivery technology is broken through.

The invention discloses a 3D (three-dimensional) visual bionic intestine-blood vessel-nerve interface organ simulation chip, which is characterized in that a micro-fluidic chip is used as a platform to construct an intestinal tract-blood vessel-brain system which simulates biological transformation of perfluorinated compounds in intestinal tracts under near physiological conditions and biologically transports the perfluorinated compounds through blood vessels; a neuronal cell culture chamber, a vascular endothelial cell culture chamber and an intestinal tract cell culture chamber are respectively arranged on the micro-fluidic chip, the culture chambers are communicated through micro-columns, and the vascular endothelial cell culture chamber serves as a barrier in the middle; perfluorinated compounds enter corresponding cell culture cavities for culture through reagent injection channels of different cell culture channels, generated metabolites are discharged through the channels, and multi-organ interaction and toxicity induced by the perfluorinated compounds are analyzed. The chip can simulate an intestinal barrier structure, a blood vessel and a neural network structure, can highly simulate biological transport and transformation of a perfluorinated compound between intestines and brains, and effectively reduces cost and time.

The invention provides a method for evaluating drug enterotoxicity in vitro through an intestinal organ model, and relates to the field of biological medicine. Comprising the following steps: preparing six different culture media, culturing the hESC by using the different culture media, inducing the hESC to respectively perform directional endoderm cell differentiation, posterior intestinal bulb differentiation, intestinal organ differentiation and intestinal organ maturation, and evaluating the drug enterotoxicity by using a prepared intestinal organ model. The intestinal organ model prepared by the invention is similar to human intestinal cells in composition, can accurately reflect the toxic effect of the medicine in the physiological environment in the human body, can be repeatedly obtained in quantity, and avoids clinical risks and ethical constraints; the sensitivity of drugs with different enterotoxicity can be reflected through cell viability, and the method is suitable for rapid evaluation of in-vitro high-flux drug enterotoxicity.

The invention relates to the technical field of microorganisms, in particular to compound probiotics for relaxing bowel and improving intestinal immunity and application thereof. The compound probiotics comprise a plant lactobacillus BXM2 strain with the preservation number of CGMCC (China General Microbiological Culture Collection Center) NO.16436 and a bifidobacterium longum subsp. Longum YYS-BSM8 strain with the preservation number of CGMCC NO.28611, and the ratio of the viable count of the plant lactobacillus BXM2 to the viable count of the bifidobacterium longum subsp. Longum YYS-BSM8 is (1-10): (1-10). After the two bacteria are compounded and combined, the gastrointestinal motility efficiency of zebra fish is accelerated, constipation is relieved, enteropathogenic bacteria are inhibited, the adhesive force of intestinal cells is improved, exopolysaccharides are produced at high yield, proliferation and phagocytic activity of macrophages are promoted, oxidative damage is remarkably relieved, and synergistic interaction is achieved in the aspects of improving the intestinal motility efficiency, relieving constipation and improving body immunity; the important application value is realized.

The invention discloses enrofloxacin composite nanogel for promoting intestinal absorption and a preparation method of the enrofloxacin composite nanogel. The enrofloxacin composite nanogel comprises 0.1-3% of sodium alginate; 0.1 to 1% of carboxymethyl chitosan; 0.05 to 0.5 percent of mint exosome; and 0.05 to 1 percent of enrofloxacin. According to the composite nanogel disclosed by the invention, the mint exosome and the enrofloxacin are prevented from being damaged by gastric juice through a shell structure of sodium alginate, so that the stability of the mint exosome and the enrofloxacin in the gastric juice is improved; after the enrofloxacin composite nanogel reaches the intestinal tract, the sodium alginate is used as a shell and is subjected to pH responsive swelling hydrolysis, and the wrapped carboxymethyl chitosan-enrofloxacin nanoparticles and the mint exosome are released; the released mint exosome opens close connection of intestinal cells, enrofloxacin is slowly released from carboxymethyl chitosan-enrofloxacin nanoparticles to achieve a slow release effect, and the mint exosome and the enrofloxacin are synergistically targeted to promote absorption of enrofloxacin in intestinal tracts, so that the drug concentration of enrofloxacin in plasma is enhanced.

The application discloses a pachymic acid medicine composition for preventing and treating ulcerative colitis and application thereof, and relates to the technical field of medical application. The composition is prepared from the following components in parts: pachymic acid 100-500 parts, carboxymethyl cellulose solution 10-100 parts, medicinal adjuvant 10-120 parts, synergistic adjuvant 10-100 parts, solvent 10-50 parts, and purified water 100-120 parts. The pachymic acid is used as a clear monomer active ingredient to prepare a medicine for preventing and treating ulcerative colitis. Compared with the existing compound, extract or multi-component combination technical scheme, the application has the characteristics of clear active ingredient, relatively clear efficacy basis, convenient quality control and subsequent development. It is clear that the ulcerative colitis can be prevented and treated by inhibiting the cGAS-STING and NF-κB signal pathways, reducing the damage of the colon epithelial cells, inhibiting the release of pro-inflammatory factors, repairing the damaged intestinal mucus barrier and intestinal epithelial barrier, regulating the apoptosis balance of intestinal cells, and enhancing the antioxidant activity of the intestinal tract. The application plays a role in preventing and treating ulcerative colitis from multiple targets such as inflammation inhibition, barrier repair and antioxidant.

The invention provides a method for relieving intestinal barrier injury caused by fluorine overexposure by using tea polyphenol. The method for relieving intestinal barrier injury caused by fluorine overexposure by using tea polyphenol comprises the following steps: carrying out an in-vitro test on porcine jejunum epithelial cells (IPEC-J2 cells) and establishing a NaF induction model by using the IPEC-J2 cells, and specifically comprises the following steps: S1, preparing test materials: the IPEC-J2 cells, a DMEM culture medium, a sterile phosphate buffer solution, fetal calf serum, mycillin and a cell freezing medium; s2, carrying out cell resuscitation, and establishing a NaF-induced cell model. The method for relieving intestinal barrier injury caused by fluorine overexposure by tea polyphenol has the advantages that the integrity of the intestinal barrier is increased and the intestinal microecology is repaired by increasing the activity of antioxidant enzyme, reducing the permeability of the intestinal tract, reducing the production of reactive oxygen species (ROS) and relieving oxidative stress and intestinal cell apoptosis caused by NaF.

Organs-on-chips are microfluidic devices for culturing living cells in micrometer sized chambers in order to model physiological functions of tissues and organs. Engineered patterning and continuous fluid flow in these devices has allowed culturing of intestinal cells bearing physiologically relevant features and sustained exposure to bacteria while maintaining cellular viability, thereby allowing study of inflammatory bowl diseases. However, existing intestinal cells do not possess all physiologically relevant subtypes, do not possess the repertoire of genetic variations, or allow for study of other important cellular actors such as immune cells. Use of iPSC-derived epithelium, including IBD patient-specific cells, allows for superior disease modeling by capturing the multi-faceted nature of the disease.

The invention discloses a liver-protecting beverage containing a composite plant exosome with optimized antioxidant capacity. The liver-protecting beverage comprises a plant exosome solution and a liver-protecting component, the plant exosome solution is a silybum marianum exosome solution and at least two of a Pingyin red rose exosome solution, a radix puerariae exosome solution, a turmeric exosome solution and a dandelion exosome solution; the liver protection component is at least one of silybum marianum micro-capsule powder, a radix puerariae extract, corn peptide, a dandelion extract and S-acetyl-L-glutathione. Hydroxyl and amido on small molecules are combined with lipid structures on the surfaces of multiple plant exosomes, small molecule active ingredients are combined through adsorption or reaction on the surfaces of the lipid structures of the exosomes, the oxidation resistance of the product can be improved, absorption of intestinal cells and probiotics is facilitated, cell metabolism is promoted, and then the fatigue feeling is reduced.

The invention belongs to the technical field of health-care food, and particularly relates to a prune exosome, a preparation method thereof and application of the prune exosome in preparation of bowel relaxing products. According to the preparation method of the prune exosome, deep processing is carried out on prune, the prune exosome is extracted from the prune, and miRNA nucleic acid contained in the prune exosome is used for promoting expression of mucoprotein genes in goblet cells and proliferation of beneficial bacteria such as bifidobacteria and lactic acid bacteria; the adverse effect of oxidative stress on intestinal cells and microbial communities is reduced by using the antioxidant activity of the prune exosome, and the effect of relaxing bowel is realized, so that the technical problem that deep processing research of prune is lacked in the prior art is solved.

The invention discloses a medicine compound for treating inflammatory diseases of colitis. The medicine compound is formed by compounding acetylated gastrodia elata gum and oxsalazine, the mass ratio of the acetylated gastrodia elata gum to the oxsalazine is (50-150): 20; the acetylated gastrodia elata gum is prepared by reacting a colloidal white solid obtained by water extraction and alcohol precipitation of gastrodia elata with acetic anhydride. According to the medicine compound, the gastrodia elata colloid polysaccharide with specific molecular weight is acetylated and subjected to porous treatment and then compounded with the oxsalazine according to a specific ratio, so that the medicine compound can be continuously released at a colon focus part, has colon targeting and slow release effects, can remarkably reduce oxidative stress of colon cells, and can be used for treating the colon focus part. The effect is better than that of any single gastrodia elata colloid polysaccharide and oxalazine, the synergistic effect is generated in the aspect of protecting colon cells, and the gastrodia elata colloid polysaccharide and oxalazine composition has actual popularization and application value.

The invention relates to the field of biology and medicine, and discloses application of dapam nitrile in prevention and / or treatment of radioactive intestinal injury. The inventor of the invention finds that dapam nitrile can protect radioactive intestinal injury induced by ionizing radiation local irradiation, including improvement of tissue pathological injury, promotion of intestinal crypt cell regeneration, inhibition of intestinal cell apoptosis, improvement of intestinal cell pyroptosis and reduction of serum inflammatory factor level; therefore, the compound can be used as a potential medicine for preventing and / or treating radioactive intestinal injury.

The invention discloses an application of an NR4A1 inhibitor in preparation of drugs related to porcine reproductive and respiratory syndrome, the invention proposes that the NR4A1 inhibitor DIM-C-pPhCO2Me can relieve intestinal injury caused by the porcine reproductive and respiratory syndrome for the first time, and the NR4A1 inhibitor can effectively improve abnormal death of intestinal cells caused by the porcine reproductive and respiratory syndrome. Experimental data show that the NR4A1 inhibitor DIM-C-pPhCO2Me can be used for effectively treating and reducing the porcine reproductive and respiratory syndrome and reducing the diarrhea rate of piglets; meanwhile, the porcine reproductive and respiratory syndrome prognosis can be effectively improved, and the growth performance of tolerant piglets is improved.

The invention provides an efficient muscle and weight gaining nanoemulsion and a preparation method thereof. The nanoemulsion is an O / W type nanoemulsion, a water phase coats creatine through maltodextrin to form a slow-release carrier, curcumin and inulin are coated in a double-layer mode in combination with phospholipid, intestinal cell absorption is enhanced through micelle membrane fusion, and the synergistic effect of curcumin anti-inflammation and inulin regulation flora is achieved; the oil phase adopts a chitosan-sodium alginate polymer to embed a BCAA / MCT compound, branched chain amino acid is released in an intestinal tract in a targeted manner to activate an mTOR pathway, MCT is slowly released to continuously supply energy, gastrointestinal discomfort caused by sudden rising of osmotic pressure is avoided, and the muscle and weight gaining efficiency is remarkably improved through a multi-component synergistic controlled release technology.

The present invention relates to an intestinal epithelium model faithfully reproducing the pathophysiological mechanisms observed in vivo in the context of an inflammatory state of the intestinal barrier. The model according to the present invention comprises two compartments separated by a semi-permeable membrane. The first compartment, corresponding to the apical pole of the intestinal epithelium, comprises a coculture of Caco-2 cells differentiated into enterocytes and HT29-MTX cells differentiated into goblet cells. The second compartment, corresponding to the basolateral pole of the intestinal epithelium, comprises a culture of THP-1 monocytic cells differentiated into macrophages.The model according to the present invention is characterized in that the cells contained in the first compartment produce interleukin (IL-6) at a concentration greater than 100 pg / mL, and interleukin 8 (IL-8) at a concentration greater than 150 pg / mL, and the cells contained in the second compartment produce tumor necrosis factor α (TNF-α) at ​​a concentration greater than 40 pg / mL and interleukin 1β (IL-1β) at a concentration greater than 90 pg / mL. The present invention also relates to the method for obtaining this model as well as to a method for selecting candidate compounds for the treatment of inflammatory bowel diseases by verifying their ability to stop inflammation upon increase in permeability or to verify the restoration of permeability and the mucus layer.

The gut microbiota produces a wide variety of metabolites, which interact with intestinal cells by modulating either gene transcription or post-translational modifications of gut proteins. The effect of gut commensal bacteria on SUMOylation, an essential ubiquitin-like modification in intestinal physiology, remains however unknown. Here, the inventors show that branched chain fatty acids (BCFAs) increase protein SUMOylation in different intestinal cell lines. They demonstrated that the hyperSUMOylation induced by BCFAs inhibits the activation of the NF-κB pathway by blocking the degradation of the inhibitory factor IκBα in response to TNFα. This results in a decrease in pro-inflammatory cytokines expression as well as a decrease in intestinal epithelial permeability in response to TNFα. Accordingly, the present invention relates to the use of Branched Chain Fatty Acids (BCFAs) for the treatment of diseases associated with intestinal inflammation such as Inflammatory Bowel Diseases and Irritable Bowel Syndrome.

The invention discloses an in-vitro drug intestinal permeability determination method based on a high-flux barrier chip, and belongs to the technical field of microfluidics and organ chips. The high-flux barrier chip adopts a three-layer structural design of a pore plate layer, a porous membrane layer and a channel layer; the porous membrane not only realizes physical separation of the pore plate layer and the channel layer, but also undertakes the core function of interlayer substance exchange, and by matching with a gravity flow driving system provided by the swing table, the fluid dynamic characteristics in the chip are guaranteed. The hole pitch of the chip is strictly matched with the standard of a commercialized pore plate, and the chip can be directly compatible with various conventional analytical instruments and has good universality. The method is suitable for determining the intestinal permeability of the passive transport compound which can be absorbed by intestinal cells. Compared with the prior art, the human intestinal cells are adopted to construct the chip model, animal experiments do not need to be carried out, related ethical disputes are thoroughly avoided, the whole operation process is simple and easy to implement, and the detection time is greatly shortened.

The invention provides a lactobacillus fermentation extraction method of marine red algae polysaccharide and application of the marine red algae polysaccharide, and the method comprises the following steps: mixing marine red algae powder with water, and carrying out pasteurization at 60-70 DEG C for 20-40 minutes; adding lactobacillus plantarum into the sterilized marine red algae turbid liquid, and performing fermentation culture to obtain a marine red algae fermentation mixed liquid; heating and extracting the marine red algae fermentation mixed solution at 85-95 DEG C for 1.5-2.5 hours, centrifuging, collecting supernate, carrying out rotary evaporation and concentration to 1 / 5 of the original volume, then adding ethanol, standing overnight, discarding the supernate, adding distilled water into precipitate for redissolving, and deproteinizing by using a Sevag method to obtain a polysaccharide solution; and dialyzing the polysaccharide solution, and concentrating and freeze-drying the dialysate to obtain the marine red algae polysaccharide. According to the method, the low-molecular-weight modified polysaccharide is obtained through lactobacillus plantarum fermentation, extraction and purification, and the low-molecular-weight modified polysaccharide is high in sulfate group content, loose in structure, capable of remarkably inhibiting AGEs-induced intestinal cell oxidative stress and inflammatory reaction, capable of being used for preparing the glycosylation injury resisting medicine and good in industrialization prospect.

The application relates to application of iron-nitrogen doped graphene in preparation of anti-radioactive enteritis drugs and belongs to the technical field of biological medicines. ZIF-8 powder, 1,10-phenanthroline powder, iron (II) acetate powder and a grinding medium are placed in a closed container to perform mechanical ball milling treatment to obtain a mixed powder; under the protection of inert gas, the mixed powder is placed in a preheated tube furnace to perform pyrolysis treatment, and is cooled to room temperature to obtain iron-nitrogen doped graphene. The iron-nitrogen doped graphene has NADH oxidase-like activity, can directly catalyze the conversion of NADH into NAD + , can rapidly supplement NAD + depletion caused by radiation, can enhance PARP-dependent DNA damage repair, can reduce the generation of active oxygen (ROS), can reduce intestinal cell death and can protect the integrity of intestinal structure, and can realize efficient protection of radioactive enteritis. Moreover, the problem of low-efficiency biosynthesis of NAD + supplementation in existing radioactive intestinal injury protection technologies is solved.

The invention discloses a monitoring method for dynamically evaluating the nano-plastic intake and discharge capacity of intestinal cells, and belongs to the technical field of environmental health risk evaluation. According to the method, full-chain dynamic evaluation of'intake-discharge 'of the intestinal cells to the nano-plastics is realized: in the intake stage, the nano-plastics marked by fluorescence act on a standardized intestinal cell model, fluorescence signals in the cells are regularly detected by flow cytometry, and a time-dependent intake rule is quantified; and in the discharge stage, continuously tracking the fluorescence intensity of the supernatant through an enzyme-linked immunosorbent assay instrument, dynamically analyzing the discharge rate of the nano-plastics, and finally evaluating the migration potential of the nano-plastics penetrating through the intestinal barrier through the permeation ratio (discharge amount / exposure amount). According to the invention, synchronous dynamic monitoring of the whole process of ingestion-discharge of nano-plastic transmembrane transport is realized for the first time, the retention kinetics law of nano-plastic is disclosed, the static limitation of traditional single-time-point detection is broken through, the method has the advantages of simple operation, high sensitivity and low cost, and an accurate and dynamic evaluation tool is provided for the intestinal barrier permeation risk of nano-plastic in the environment.

The invention relates to the technical field of biology, in particular to recombinant lactic acid bacteria capable of improving the serum melatonin level and a construction method of the recombinant lactic acid bacteria. According to the recombinant lactic acid bacteria, melatonin synthetase AANAT and HIOMT genes are introduced through a genetic engineering technology and are stably expressed in genomes of the recombinant lactic acid bacteria, so that the recombinant lactic acid bacteria have the capability of secreting melatonin synthetase. The lactic acid bacteria are food-grade strains without resistance selection markers, have good biological safety and can enter intestinal tracts through oral administration. After oral administration, the recombinant lactic acid bacteria secrete melatonin synthetase in intestinal tracts, promote intestinal cells to synthesize melatonin, and improve the level of melatonin in serum through an intestinal-blood barrier. Serum detection shows that the recombinant lactic acid bacteria can significantly improve the concentration of serum melatonin. Compared with the prior art, the invention provides a safe and effective food-grade recombinant lactic acid bacteria preparation which is suitable for promoting the improvement of the endogenous melatonin level of a human body and has a wide application prospect.