Application of bacteroides fragilis in improvement and / or treatment of enteritis

Abstract

Different animal colitis model tests prove that the bacteroides fragilis, especially the inactivated bacterial liquid and inactivated bacterial powder of the bacteroides fragilis ZY-312 with the preservation number of CGMCC (China General Microbiological Culture Collection Center) No.10685, have the effects of improving and treating infectious enteritis and non-infectious enteritis. The inactivated bacteroides fragilis powder with the complete form, provided by the invention, has a good effect on improving non-infectious enteritis and colitis under different concentration formulas, has no side effects on organisms, and has very good edible and application prospects.

Description

Technical Field

[0001] The present invention relates to an application of Bacteroides fragilis, and in particular to an application of Bacteroides fragilis in improving and / or treating enteritis. Background Art

[0002] Enteritis refers to an inflammatory reaction of the intestine caused by various reasons such as microbial infection, ischemia, radiation or immune disorders. The most common symptoms are abdominal pain, diarrhea, bloody stools, fever, etc. In severe cases, it can cause dehydration and electrolyte imbalance, and even threaten life. Enteritis can be divided into inflammatory enteritis and non-infectious enteritis according to the different causes of the disease. Inflammatory enteritis can be divided into Crohn's disease and ulcerative colitis according to the different locations of the disease. Non-infectious enteritis includes allergic colitis, radiation enteritis, necrotizing enteritis, ischemic enteritis and dysbacteriosis enteritis.

[0004] When clinical symptoms such as abdominal pain, diarrhea, bloody stools and fever occur, medical treatment should be sought promptly. At present, the diagnosis of enteritis is mainly based on laboratory tests (blood-related tests, stool tests) and imaging tests (CT or MRI, contrast examinations, mesenteric vascular CT angiography). If necessary, small intestinal endoscopy, colonoscopy, sigmoidoscopy, rectoscopy, etc. can be selected according to the location of the lesion. When lesions are found under endoscopy, the lesion tissue can be further taken for pathological examination. In the early treatment of infectious enteritis in the clinic, sensitive anti-infective drugs can be selected empirically, and drugs can be adjusted in time according to the results of bacterial culture. More sensitive anti-infective drugs can be selected. Long-term use of drugs is prone to antibiotic resistance. Inflammatory enteritis is mostly treated with immunosuppressive therapy. Clinical treatment is mainly based on anti-inflammatory drugs such as salicylates, glucocorticoids and immunosuppressants. The condition is prone to relapse, and long-term medication often brings a large economic and social burden.

[0005] Current evidence shows that probiotics play an important role in Clostridium difficile infection, inflammatory bowel disease, irritable bowel syndrome, infectious gastroenteritis and necrotizing enteritis. Huang M et al. used mesalazine combined with triple live bifidobacteria to treat UC. The results showed that the clinical symptom scores, disease activity index, and inflammatory factors of patients were significantly lower than those of the control group, and the incidence of adverse reactions was low. It showed a great protective effect on the mucosa of UC patients, suggesting that probiotics can restore the intestinal mucosal barrier function. At present, most of the research on probiotics is live bacteria, while there are few studies on inactivated bacteria. In order to fill this research gap, new ideas are provided for the subsequent development of probiotic products. Summary of the invention

[0006] In view of the above problems, the present invention provides use of Bacteroides fragilis in improving and / or treating enteritis.

[0007] In order to better solve the above problems, the present invention adopts the following technical solutions:

[0008] In a first aspect, the present invention provides the use of Bacteroides fragilis in preparing a product for improving and / or treating enteritis, wherein the Bacteroides fragilis is a killed bacterium;

[0009] The Bacteroides fragilis is selected from Bacteroides fragilis ZY-312 and Bacteroides fragilis NCTC9343 with a deposit number of CGMCC No.10685.

[0010] According to an embodiment of the present invention, the enteritis includes non-infectious enteritis and colitis;

[0011] According to an embodiment of the present invention, the non-infectious enteritis includes radiation enteritis and allergic colitis;

[0012] And / or, the colitis includes Crohn's disease and ulcerative colitis.

[0013] According to an embodiment of the present invention, the radiation enteritis is radiation colitis caused by X-rays;

[0014] And / or, the allergic colitis is diet-induced idiopathic colitis.

[0015] According to an embodiment of the present invention, the inactivated bacteria are morphologically intact inactivated bacteria and / or morphologically incomplete inactivated bacteria.

[0016] According to an embodiment of the present invention, the inactivated bacteria are inactivated by any one or more of dry heat, wet heat, filtration, organic solvents, chemical reagents, ultraviolet or infrared rays, fermentation, freeze drying, gene recombination, gene modification or transformation.

[0017] According to an embodiment of the present invention, the inactivated bacteria is inactivated Bacteroides fragilis bacteria powder.

[0018] Preferably, the preparation method of the inactivated Bacteroides fragilis powder is as follows: fermenting and culturing Bacteroides fragilis and centrifuging to obtain bacterial cells, washing the bacterial cells with a sodium chloride aqueous solution and centrifuging to obtain washed bacterial cells, adding an excipient to resuspend, inactivating and centrifuging to obtain inactivated bacterial sludge, and drying.

[0019] Further preferably, the preparation method of the inactivated Bacteroides fragilis powder is as follows:

[0020] (1) fermenting Bacteroides fragilis, centrifuging the fermentation broth after the fermentation is completed, and collecting the bacterial cells;

[0021] (2) adding sodium chloride aqueous solution at a weight volume ratio of 1 g of bacterial cells to sodium chloride aqueous solution (10-30) mL) for washing, and centrifuging to obtain washed bacterial cells;

[0022] (3) adding the first excipient solution to the washed bacterial cells, mixing and resuspending to obtain a bacterial cell solution, then performing an inactivation treatment, centrifuging, and collecting the inactivated bacterial sludge;

[0023] (4) adding a second excipient solution to the inactivated bacteria sludge obtained in step (3) to obtain an inactivated bacteria stock solution;

[0024] (5) Drying the inactivated bacteria stock solution obtained in step (4) until the residual moisture is less than 5 wt %, thereby obtaining inactivated Bacteroides fragilis bacteria powder.

[0025] According to an embodiment of the present invention, the inactivated bacteria is a suspension of inactivated bacteria powder;

[0026] Preferably, the preparation method of the inactivated bacterial powder suspension is as follows: fermenting and culturing Bacteroides fragilis and centrifuging to obtain bacterial cells, washing the bacterial cells with a sodium chloride aqueous solution and centrifuging to obtain washed bacterial cells, adding an excipient to resuspend, inactivating and centrifuging to obtain inactivated bacterial mud, drying to obtain inactivated bacterial powder, and stirring the inactivated bacterial powder with water to prepare the inactivated bacterial powder suspension;

[0027] Further preferably, the preparation method of the inactivated bacteria powder suspension is as follows:

[0028] (1) fermenting Bacteroides fragilis, centrifuging the fermentation broth after the fermentation is completed, and collecting the bacterial cells;

[0029] (2) adding sodium chloride aqueous solution at a weight volume ratio of 1 g of bacterial cells to sodium chloride aqueous solution (10-30) mL) for washing, and centrifuging to obtain washed bacterial cells;

[0030] (3) adding the first excipient solution to the washed bacterial cells, mixing and resuspending to obtain a bacterial cell solution, then performing an inactivation treatment, centrifuging, and collecting the inactivated bacterial sludge;

[0031] (4) adding a second excipient solution to the inactivated bacteria sludge obtained in step (3) to obtain an inactivated bacteria stock solution;

[0032] (5) drying the inactivated bacteria stock solution obtained in step (4) until the residual moisture content is less than 5 wt %, thereby obtaining inactivated Bacteroides fragilis bacteria powder;

[0033] (6) Add water to the inactivated bacteria powder obtained in step (5) in a mass ratio of bacteria powder to water = 1: (2-5), stir with a stirrer, and prepare an inactivated bacteria powder suspension.

[0034] According to an embodiment of the present invention, in step (1), the bacterial count of the fermentation liquid reaches 10 8 CFU / mL and above.

[0035] According to an embodiment of the present invention, in step (2), the mass concentration of the sodium chloride aqueous solution is 0.6-1.5wt%, preferably 0.65-1.2wt%, more preferably 0.8-1.0wt%, most preferably 0.85-0.95wt%, for example 0.9wt% sodium chloride aqueous solution.

[0036] According to an embodiment of the present invention, the first excipient in step (3) is the same as or different from the second excipient in step (4), and is independently selected from at least one of mannitol, sorbitol, maltodextrin, lactose, sodium chloride, maltose, sucrose, glucose, trehalose, dextran, proline, lysine, alanine, casein, and skim milk.

[0037] According to an embodiment of the present invention, in step (3), the weight-to-volume ratio of the bacteria to the first excipient solution is 1 g:(5-40) mL.

[0038] According to an embodiment of the present invention, in step (3) and / or step (4), the mass fraction of the excipient is 4 to 30 wt%.

[0039] According to an embodiment of the present invention, in step (3) and / or step (4), the excipient solution is selected from a sodium chloride aqueous solution; preferably, the excipient solution is selected from physiological saline, such as a 0.9 wt % sodium chloride aqueous solution.

[0040] According to an embodiment of the present invention, in step (3), the inactivation method is selected from at least one of heat inactivation, freeze inactivation or chemical inactivation, preferably heat inactivation.

[0041] Exemplarily, the temperature of the heat inactivation is 60 to 100° C., and the time of the heat inactivation is 10 to 60 minutes.

[0042] According to an embodiment of the present invention, in step (4), a second excipient solution is added to make the total weight of the inactivated bacterial stock solution consistent with the weight of the bacterial solution before inactivation in step (3).

[0043] Illustratively, the second excipient solution is the same as the first excipient solution.

[0044] According to an embodiment of the present invention, in step (5), the drying method is selected from vacuum freeze drying and spray drying, preferably vacuum freeze drying.

[0045] According to an embodiment of the present invention, the conditions for vacuum freeze-drying include: a freezing temperature of -20 to -40°C, a freezing time of 1 to 3 hours, and a vacuum degree of 0.20 to 0.25 mbar; illustratively, the process of vacuum freeze-drying includes: pre-freezing at -40±2°C for 1 to 3 hours, pre-freezing at -20±2°C for 0.5 to 1h, and finally freezing at -40±2°C for 0.5 to 2h, and preparing the inactivated bacterial powder through primary drying and analytical drying under a vacuum degree of 0.25 mbar.

[0046] According to an embodiment of the present invention, in the preparation method, the centrifugal conditions are not specifically limited, as long as the desired centrifugal effect can be achieved, for example, the centrifugal speed is 10000-20000 rpm.

[0047] According to an embodiment of the present invention, in step (6), the stirrer is stirred at 500 to 1000 rpm for 10 to 30 min until there are no particles visible to the naked eye in the suspension;

[0048] and / or, prepared to a bacterial concentration of 2×10 10 Cells / g or above inactivated bacteria powder suspension.

[0049] According to an embodiment of the present invention, the product may be any one of a pharmaceutical composition, a food, a health product or a food additive.

[0050] Preferably, the pharmaceutical composition contains a pharmaceutically effective dose of inactivated Bacteroides fragilis ZY-312 powder with a preservation number of CGMCC No.10685.

[0051] In the above-mentioned pharmaceutical composition, the pharmaceutically effective dose is 10 7 -10 9 Cells / mL.

[0052] In the above-mentioned pharmaceutical composition, the dosage form of the pharmaceutical composition is pills, tablets, granules, capsules, powders, suspensions, oral liquids or enema; preferably, the pharmaceutical composition is administered orally or by enema.

[0053] The above-mentioned pharmaceutical composition has an administration cycle of intermittent administration, periodic administration, continuous administration or long-term administration.

[0054] In a second aspect, the present invention provides the use of Bacteroides fragilis in preparing a product for improving and / or treating non-infectious enteritis, wherein the Bacteroides fragilis is a live bacterium; the Bacteroides fragilis is Bacteroides fragilis ZY-312 with a preservation number of CGMCC No.10685.

[0055] According to an embodiment of the present invention, the non-infectious enteritis includes radiation enteritis and allergic colitis.

[0056] According to an embodiment of the present invention, the radiation enteritis is radiation colitis caused by X-rays;

[0057] And / or, the allergic colitis is diet-induced idiopathic colitis.

[0058] According to an embodiment of the present invention, the product may be any one of a pharmaceutical composition, a food, a health product or a food additive.

[0059] In the above-mentioned pharmaceutical composition, the dosage form of the pharmaceutical composition is pills, tablets, granules, capsules, powders, suspensions, oral liquids or enema; preferably, the pharmaceutical composition is administered orally or by enema.

[0060] The above-mentioned pharmaceutical composition has an administration cycle of intermittent administration, periodic administration, continuous administration or long-term administration.

[0061] Compared with the prior art, the present invention has the following beneficial effects:

[0062] The present invention proves through different animal colitis model tests that Bacteroides fragilis, especially the inactivated bacterial liquid and inactivated bacterial powder of Bacteroides fragilis ZY-312 with a deposit number of CGMCC No. 10685, has the effect of improving and treating infectious enteritis and non-infectious enteritis. The inactivated bacterial powder of Bacteroides fragilis with complete morphology provided by the present invention has good effects on improving non-infectious enteritis and colitis under different concentration formulas and has no side effects on the body, and has good edible and application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 This is a colony morphology diagram of Bacteroides fragilis ZY-312 after anaerobic culture of the present invention;

[0064] Figure 2 This is a Gram staining microscopic image of Bacteroides fragilis ZY-312 of the present invention;

[0065] Figure 3 It is a transmission electron microscope image of the inactivated Bacteroides fragilis ZY-312 bacterial powder of the present invention.

[0066] The microbial strains used in the implementation of the present invention have been deposited in the General Microbiological Center (CGMCC) of the China Microbiological Culture Collection Committee (No. 3, Yard No. 1, Beichen West Road, Chaoyang District, Beijing) on ​​April 2, 2015. Classification name: Bacteroides fragilis ZY-312, deposit number CGMCC No.10685. Bacteroides fragilis ZY-312 was isolated and obtained by the applicant of the present invention, and has been protected by a patent (patent number 201510459408.X). According to the provisions of the Patent Examination Guidelines, the public can buy it from commercial channels or it has been authorized, and no deposit is required, that is, no deposit certificate is required. DETAILED DESCRIPTION

[0067] The technical scheme of the present invention will be further described in detail below in conjunction with specific embodiments. It should be understood that the following embodiments are only exemplary descriptions and explanations of the present invention and should not be construed as limiting the scope of protection of the present invention. All technologies implemented based on the above content of the present invention are included in the scope that the present invention is intended to protect.

[0068] Unless otherwise specified, the raw materials and reagents used in the following examples are commercially available or can be prepared by known methods.

[0069] In the following examples and comparative examples, unless otherwise specified, Bacteroides fragilis was fermented and cultured using methods known in the art, wherein the deposit number of Bacteroides fragilis ZY-312 is NO.10685.

[0070] Example 1 Fermentation culture of Bacteroides fragilis

[0071] The Bacteroides fragilis ZY-312 strain was streaked onto a blood plate and cultured anaerobically for 48 hours. The colony morphology, staining characteristics, size, club shape, and distribution were observed.

[0072] Colony characteristics: After 48 hours of culture on a blood plate, Bacteroides fragilis ZY-312 is round, slightly convex, translucent, white, smooth, and non-hemolytic. The colony diameter is between 1 and 3 mm. Figure 1 .

[0073] Microscopic morphology: Gram staining of Bacteroides fragilis ZY-312 showed that it was a Gram-negative bacterium with a typical rod shape, blunt and darkly stained ends, and a non-stained part in the middle of the bacteria that looked like a vacuole. Figure 2 .

[0074] A single colony was selected and inoculated into the culture medium for fermentation culture for 8 hours (temperature was 37°C). The obtained bacterial solution was centrifuged at a speed of 3000 r / min for 15 min. The supernatant was removed and the precipitate was collected to obtain Bacteroides fragilis ZY-312 bacterial sludge.

[0075] Example 2 Sample preparation

[0076] 1. Preparation of live and inactivated Bacteroides fragilis solutions

[0077] (1) Enrichment: A single colony was selected from the anaerobically cultured colonies in Example 1 and inoculated into TSB (tryptone soy broth containing 5% fetal bovine serum) for enrichment and fermentation. The resulting bacterial solution was stored for later use.

[0078] (2) Bacteroides fragilis ZY-312 live bacterial solution: The bacterial solution prepared in step (1) was measured for bacterial count using a McFarland turbidimeter tube and diluted to 10 with physiological saline. 6 CFU / mL, 10 7 CFU / mL, 10 8 CFU / mL, 10 9 CFU / mL and 10 10 CFU / mL, save for future use.

[0079] (3) Inactivated Bacteroides fragilis ZY-312 solution: Prepare inactivated Bacteroides fragilis solution by high temperature or ultraviolet irradiation. 7 CFU / mL, 10 9 5 mL of live bacterial solution of Bacteroides fragilis with a CFU / mL is placed in a beaker, and the beaker containing the bacterial solution is placed in a constant temperature water bath at 100°C for 20 to 30 minutes or in an ultraviolet environment for 30 to 60 minutes to prepare the inactivated bacterial solution of Bacteroides fragilis.

[0080] 2. Preparation of inactivated Bacteroides fragilis powder

[0081] (1) Take the fermentation broth of Bacteroides fragilis prepared in Example 1, centrifuge the fermentation broth, collect wet bacteria, add physiological saline at a ratio of bacteria: physiological saline = 1: (10-30) (m:v) to resuspend and wash the bacterial sludge, and centrifuge again to collect the washed bacteria. m represents mass and v represents volume.

[0082] (2) Add an excipient prepared by mixing 5% maltodextrin and 0.9% sodium chloride to the bacterial cells obtained in step (1) at a ratio of bacterial cells: excipient = 1: (5-15) (m:m), stir and disperse, heat inactivate at (60-90) ± 5°C for (30-50) ± 5 minutes, and then centrifuge to collect the bacterial sludge.

[0083] (3) adding excipients to the inactivated bacteria sludge collected in step (2) to make the total weight consistent with the weight of the bacteria solution before inactivation, stirring to completely dissolve, and obtaining an inactivated bacteria powder stock solution.

[0084] (4) The inactivated bacterial powder stock solution obtained in step (3) is subjected to vacuum freeze drying, pre-frozen at -40±2°C for 1 to 3 hours, pre-frozen at -20±2°C for 0.5 to 1 hour, and finally pre-frozen at -40±2°C for 0.5 to 2 hours, and then dried once (at -5±2°C and 0±2°C) and dried by desorption (at 35±2°C) under a vacuum degree of 0.25 mbar to prepare inactivated bacterial powder, wherein the bacterial count of the bacterial powder reaches 1×10 11 Cells / g or more. It can be seen from the transmission electron microscopy that the bacteria in the prepared inactivated bacteria powder have complete morphology. Figure 3 .

[0085] 3. Preparation of inactivated Bacteroides fragilis powder suspension:

[0086] (1) Take the fermentation broth of Bacteroides fragilis prepared in Example 1, centrifuge the fermentation broth, collect wet bacteria, add physiological saline at a ratio of bacteria: physiological saline = 1: (10-30) (m:v) to resuspend and wash the bacterial sludge, and centrifuge again to collect the washed bacteria. m represents mass and v represents volume.

[0087] (2) Add an excipient prepared by mixing 5% maltodextrin and 0.9% sodium chloride to the bacterial cells obtained in step (1) at a ratio of bacterial cells: excipient = 1: (5-15) (m:m), stir and disperse, heat inactivate at (60-90) ± 5°C for (30-50) ± 5 minutes, and then centrifuge to collect the bacterial sludge.

[0088] (3) adding excipients to the inactivated bacteria sludge collected in step (2) to make the total weight consistent with the weight of the bacteria solution before inactivation, stirring to completely dissolve, and obtaining an inactivated bacteria powder stock solution.

[0089] (4) The inactivated bacterial powder stock solution obtained in step (3) is subjected to vacuum freeze drying, pre-frozen at -40±2°C for 1 to 3 hours, pre-frozen at -20±2°C for 0.5 to 1 hour, and finally pre-frozen at -40±2°C for 0.5 to 2 hours, and then dried once (at -5±2°C and 0±2°C) and dried by desorption (at 35±2°C) under a vacuum degree of 0.25 mbar to prepare inactivated bacterial powder, wherein the bacterial count of the bacterial powder reaches 1×10 11 Cells / g or above.

[0090] (5) Add the inactivated bacterial powder obtained in step (4) to purified water in a ratio of bacterial powder to purified water = 1: (2-5) (m:m), stir at 500-1000 rpm for 10-30 min until there are no visible particles in the suspension, and prepare a suspension with a bacterial cell concentration of 2×10 10The same method as above was used to prepare NCTC 9343 inactivated bacteria powder and inactivated bacteria powder suspension.

[0091] The inactivated bacteria liquid and inactivated bacteria powder suspension (inactivated bacteria liquid) prepared in this example were used in the following examples.

[0092] Example 3 Effects of Bacteroides fragilis on rats with radiation enteritis

[0093] 1. Experimental Design

[0094] 160 SD female rats with a body weight of (160±20)g were selected as experimental animals. The rats were kept in the animal room for 2 weeks and the rats were observed to determine that the rats were in good condition. The rats were randomly divided into a blank group of 20 and a modeling group of 140, and randomly divided into a model group, a positive control group, a NCTC 9343 inactivated bacterial powder group, a Bacteroides fragilis Bd-312 live bacterial liquid and a Bacteroides fragilis ZY-312 live bacterial liquid, inactivated bacterial liquid and inactivated bacterial powder group, with 20 mice in each group. The modeling group was anesthetized with 7% chloral hydrate (600-700μL) and fixed with a fixing frame (4 rats each time) and placed on the small animal radiation research platform (SARRP). The rats were irradiated once with a dose of 20Gy in the Department of Radiation of the Cancer Hospital, ranging from the pubic symphysis to the anus, and the irradiation field area was 4cm×5cm to construct a rat radiation rectal injury model. After irradiation, the rats were returned to the cage, and the temperature in the animal room was maintained at 25℃, humidity at 10%, and light-dark cycle at 12h. The body weight of rats was recorded every day.

[0095] After successful modeling, the normal group and the model group were gavaged with physiological saline at 0.01 mL / g body weight once a day, and the standard strain of Bacteroides fragilis, live bacterial liquid, inactivated bacterial liquid and inactivated bacterial powder suspension at 0.01 mL / g body weight once a day for 28 consecutive days. Samples were collected on the 5th, 14th, 21st and 28th days after administration to observe the rectal tissue characteristics of the rats.

[0096] Rat rectal tissue was baked at 60℃ for 1-2h; dewaxed and rehydrated; hematoxylin stained for 5min; rinsed in distilled water; differentiated in 0.1% HCl / ethanol: differentiated in 0.1% HCl / ethanol for a few seconds, washed and sliced ​​again, 3 times in total; 10min each time; stained with eosin staining solution for 2-3min (can be extended to 10min depending on the actual situation); rinsed in tap water for 5min; baked the slices at 60℃ for 15min; dehydrated in 80% ethanol.

[0097] The experimental results were analyzed using SPSS 25.0 statistical software. The measurement data were expressed as mean ± standard deviation (x ± s). One-way ANOVA was used for comparison among multiple groups, and LSD test was used for pairwise comparison of means among groups.

[0098] Table 1 Effect groups and dosing regimens in rats with radiation enteritis

[0099] Group Dosage regimen Blank group Intragastric administration of saline Model Group Intragastric administration of saline Positive control group (mesalazine) Oral administration of 10 mL / kg mesalazine NCTC 9343 inactivated bacteria powder group <![CDATA[Gavage with 1×10 8 Cells / mL suspension of heat-inactivated NCTC 9343 bacterial powder]]> Bacteroides fragilis Bd-312 live bacteria liquid group <![CDATA[Gavage with 1×10 8 CFU / mL of live Bacteroides fragilis suspension]]> Bacteroides fragilis ZY-312 live bacteria liquid group <![CDATA[Gavage with 1×10 8 CFU / mL live Bacteroides fragilis suspension]]> Bacteroides fragilis ZY-312 inactivated bacteria liquid group <![CDATA[Gavage with 1×10 8 Cells / mL of heat-inactivated Bacteroides fragilis]]> Bacteroides fragilis ZY-312 inactivated bacteria powder group <![CDATA[Gavage with 1×10 8 Cells / mL suspension of heat-inactivated Bacteroides fragilis]]>

[0100] 2. Experimental Results

[0101] Table 2 Effect of Bacteroides fragilis on body weight of rats with radiation colitis

[0102]

[0103]

[0104] Note: Compared with the model group, ***P<0.001; compared with the positive drug group, # P<0.05; compared with the inactivated Bacteroides fragilis ZY-312 liquid group, + P<0.05

[0105] As shown in Table 2, there was no significant difference in the body weight of rats in each group at the time of enrollment (P>0.05). At the end of the experiment, the changes in body weight of rats were compared with those in the normal group. The body weight of rats in the modeling group irradiated with 20Gy X-rays was reduced, and the body weight reduction rate of rats in the positive drug group and the Bacteroides fragilis groups slowed down. After 7 days, the body weight of rats gradually increased. After one-way analysis of variance, the difference between the model group and the drug group was statistically significant (P<0.001); further test and analysis showed that compared with the positive drug group, the Bacteroides fragilis ZY-312 inactivated bacterial solution group, the Bacteroides fragilis ZY-312 inactivated bacterial powder group and the Bacteroides fragilis ZY-312 live bacterial solution group had a stronger therapeutic effect (P<0.05), and there was no difference between the NCTC 9343 inactivated bacterial powder group and the Bacteroides fragilis Bd-312 live bacterial solution group (P>0.05). Compared with the inactivated Bacteroides fragilis ZY-312 liquid group, the therapeutic effect of the live Bacteroides fragilis ZY-312 liquid group was weaker (P<0.05), while the therapeutic effect of the inactivated Bacteroides fragilis ZY-312 powder group was equivalent to that of the live Bacteroides fragilis ZY-312 liquid group (P>0.05).

[0106] The pathological changes of rectal tissues in the normal group were normal; on the 5th day after irradiation, the modeling group had inflammatory reaction, local neutrophil infiltration under the mucosa, mucosal edema, hyperplasia, congestion, intestinal gland expansion, goblet cell reduction, intestinal mucosal congestion aggravated after 14 days, muscle fiber slight degeneration, goblet cell reduction significantly, intestinal mucosal shedding occurred after 21 days; on the 5th day after irradiation, the positive control group had local neutrophil infiltration under the mucosa, mucosal edema, hyperplasia, slight congestion, bleeding disappeared on the 14th day, and slight edema appeared in the intestinal mucosa after 28 days; on the 5th day after irradiation, the enteritis symptoms of the NCTC9343 inactivated bacteria powder group and the Bacteroides fragilis Bd-312 live bacteria liquid group were similar to those of the modeling group, with a small amount of lymphocyte infiltration in the submucosal layer, mild The symptoms of enteritis disappeared after 21 days. The enteritis symptoms of the Bacteroides fragilis ZY-312 live bacteria liquid group were similar to those of the modeling group on the 5th day after radiation, with a small amount of lymphocyte infiltration in the submucosal layer, mild bleeding, and a decrease in goblet cells. After 7 days, the lymphocyte infiltration in the rectal mucosa was restored, and the goblet cells increased. After 14 days, the symptoms of enteritis disappeared. The symptoms of enteritis of the Bacteroides fragilis ZY-312 inactivated bacteria liquid group and the Bacteroides fragilis ZY-312 inactivated bacteria powder group were similar to those of the modeling group on the 5th day after radiation, with a small amount of lymphocyte infiltration in the submucosal layer, mild bleeding, slight edema of the mucosa on the 7th day, and the bleeding disappeared. After 14 days, the symptoms of enteritis disappeared.

[0107] Example 4 Effect of Bacteroides fragilis on allergic colitis mice

[0108] 1. Experimental Design

[0109] 80 healthy female BALB / c mice aged 7 days were selected. The mice were breastfed by their mothers before 3 weeks of age. After 3 weeks of age, they ate and drank water by themselves and were exposed to day and night cycles of light. At about 7-8 weeks of age, they were randomly divided into a blank group of 10 mice and a modeling group of 70 mice. They were randomly divided into a model group, a positive control group, a NCTC 9343 inactivated bacterial powder group, and a Bacteroides fragilis Bd-312 live bacterial liquid, a Bacteroides fragilis ZY-312 live bacterial liquid, an inactivated bacterial liquid, and an inactivated bacterial powder group, with 10 mice in each group. The Bacteroides fragilis group was continuously gavaged with a suspension of Bacteroides fragilis live bacterial liquid, inactivated bacterial liquid, and inactivated bacterial powder (0.02 mL / g body weight) for 15 days, once a day (days 0 to 14 of the experiment). The model group and the blank group were gavaged with 0.2 mL / 10 g of normal saline, and the positive control group was gavaged with 0.5 mg / kg of promethazine. On the 15th day of the experiment, the abdominal skin of the young mice was shaved to a size of 2 cm × 2 cm. The model group was sensitized by skin instillation of 0.2 mL of 3% oxazolone 100% ethanol solution, while the blank group was sensitized by skin instillation of an equal volume of PBS solution, which was then air-dried and repeated 24 hours later (the 16th day of the experiment). After 5 days (the 21st day of the experiment), colon perfusion was performed. First, 10% chloral hydrate (0.3 mL per 100 g of the body weight of the young mice) was injected intraperitoneally for anesthesia. The modeling group was given 0.15 mL of 1% oxazolone 50% ethanol solution enema with an enema device (inserted about 3 to 4 cm into the anus of the young mice, and the blank group was given an equal volume of normal saline enema. After injection, the young mice were inverted for 60 seconds to allow the sensitizing solution to fully contact the colon. After the second day of enema, the body weight, stool characteristics and occult blood in the stool of the young mice were recorded daily for 3 consecutive days (the 22nd to 24th day of the experiment), and diarrhea scores were performed. If the young mice eat less, lose weight, have dull fur, are lazy, have reduced activity, have loose stools or have a positive blood test in the stool, the modeling is considered to be successful.

[0110] Samples were collected 3 days after colon perfusion (24th day of the experiment). The mice were killed after anesthesia, the skin was cut along the midline of the abdomen, the abdominal cavity was opened to expose the colon, and the colon tissue with obvious lesions was taken. After carefully scraping off the feces and other contents, the intestinal segment (about 1 to 1.5 cm) was cut and rinsed with PBS solution, and the expression levels of related cytokines IFN-γ and IL-10 were measured.

[0111] The experimental results were analyzed using SPSS 25.0 statistical software. The measurement data were expressed as mean ± standard deviation (x ± s). One-way ANOVA was used for comparison among multiple groups, and LSD test was used for pairwise comparison of means among groups.

[0112] 2. Experimental Results

[0113] Table 3 Effects of Bacteroides fragilis on body weight and diarrhea scores of BALB / c mice with allergic colitis

[0114]

[0115]

[0116] Note: Compared with the model group, **P<0.01, **P<0.001; compared with the positive drug group, #P<0.05; compared with the Bacteroides fragilis ZY-312 inactivated bacteria liquid group, + P<0.05

[0117] As shown in Table 3, after the experiment, the body weight of mice in the positive control group and each group of Bacteroides fragilis was significantly higher than that in the model group (P<0.01). From the perspective of diarrhea index, the positive control group and each group of Bacteroides fragilis could improve the diarrhea of ​​mice (P<0.001). Further test and analysis showed that compared with the positive drug group, the Bacteroides fragilis ZY-312 inactivated bacterial liquid group, the Bacteroides fragilis ZY-312 inactivated bacterial powder group and the Bacteroides fragilis ZY-312 live bacterial liquid group had stronger therapeutic effects (P<0.05), and there was no difference between the NCTC 9343 inactivated bacterial powder group and the Bacteroides fragilis Bd-312 live bacterial liquid group (P>0.05). Compared with the Bacteroides fragilis ZY-312 inactivated bacterial liquid group, the Bacteroides fragilis ZY-312 live bacterial liquid group had weaker efficacy (P<0.05), and the Bacteroides fragilis ZY-312 inactivated bacterial powder group had equivalent efficacy (P>0.05).

[0118] Table 4 Effects of Bacteroides fragilis on IFN-γ and IL-10 in mouse colon

[0119] Group IFN-γ (pg / mL) IL-10 (pg / mL) Blank group <![CDATA[372.6±18.6 *** ]]> <![CDATA[75.2±6.5 *** <!-- 8 -->]]> Model Group 170.8±11.2 44.0±4.0 Positive control group (promethazine) <![CDATA[303.8±24.3 *** ]]> <![CDATA[68.1±8.6 ***+ ]]> NCTC 9343 inactivated bacteria powder group <![CDATA[303.8±17.2 *** ]]> <![CDATA[68.5±14.1 ***+ ]]> Bacteroides fragilis Bd-312 live bacteria liquid group <![CDATA[301±16.4 *** ]]> <![CDATA[65.8±5.7 ***+ ]]> Bacteroides fragilis ZY-312 live bacteria liquid group <![CDATA[338.6±15.9 ***#+ ]]> <![CDATA[80.3±8.4 ***#+ ]]> Bacteroides fragilis ZY-312 inactivated bacteria liquid group <![CDATA[358.6±10.9 ***# ]]> <![CDATA[92.3±8.3 ***# ]]> Bacteroides fragilis ZY-312 inactivated bacteria powder group <![CDATA[351.6±9.2 ***# ]]> <![CDATA[90.8±7.5 ***# ]]>

[0120] Note: Compared with the model group, ***P<0.001; compared with the positive control group, # P<0.05; compared with the inactivated Bacteroides fragilis ZY-312 liquid group, + P<0.05.

[0121] As shown in Table 4, after the experiment, compared with the model group, the IFN-γ and IL-10 levels in the rat tissues of the positive control group and the Bacteroides fragilis groups were significantly higher than those in the model group. The one-way ANOVA showed that the differences between the model group and the drug-treated group were statistically significant. Further test and analysis showed that compared with the positive drug group, the Bacteroides fragilis ZY-312 inactivated bacterial solution group, the Bacteroides fragilis ZY-312 inactivated bacterial powder group and the Bacteroides fragilis ZY-312 live bacterial solution group had stronger therapeutic effects (P<0.05), and there was no difference between the NCTC9343 inactivated bacterial powder group and the Bacteroides fragilis Bd-312 live bacterial solution group (P>0.05). Compared with the Bacteroides fragilis ZY-312 inactivated bacterial solution group, the Bacteroides fragilis ZY-312 live bacterial solution group had weaker efficacy (P<0.05), and the Bacteroides fragilis ZY-312 inactivated bacterial powder group had equivalent efficacy (P>0.05).

[0122] Example 5 Effect of inactivated Bacteroides fragilis on Crohn's disease mice

[0123] 1. Experimental Design

[0124] 160 healthy male BALB / c mice aged 6-8 weeks, weighing 18-22g, were randomly divided into a blank group of 20 mice and a modeling group of 140 mice, and randomly divided into a model group, a positive control group, a NCTC 9343 inactivated bacterial powder group, a Bacteroides fragilis Bd-312 live bacterial liquid group, and a Bacteroides fragilis ZY-312 live bacterial liquid, inactivated bacterial liquid and inactivated bacterial powder group, with 20 mice in each group. The model group was anally infused with 100μL of a mixture of TNBS aqueous solution and 50% ethanol (1:1), and fasted for 24h before modeling, but not water. The control group mice were anally infused with 100μL of normal saline. After the liquid was slowly infused, the catheter was removed, and the mice were kept in an inverted position for 60s. After enema, they were fed normally. The disease activity of the mice was observed and recorded daily. If the weight of the mice continued to decrease for 3 consecutive days and bloody stools appeared, the modeling was successful.

[0125] After modeling, the mice were gavaged and administered (0.1 mL / 10 g body weight) twice a day for 28 consecutive days. After 28 days, blood was drawn from the abdominal aorta to detect the levels of IL-6 and IL-10 in the mouse serum, and the mice were killed by cervical dislocation. The weight, stool characteristics and blood in stool of each group of mice were recorded every day, and the disease activity index (DAI) score of the mice was calculated.

[0126] The experimental results were analyzed using SPSS 25.0 statistical software. The calculation results were expressed as mean ± standard deviation (x ± s). One-way ANOVA was used for comparison among multiple groups, and LSD test was used for pairwise comparison of means among groups. The survival rate was analyzed by chi-square test.

[0127] Table 5 Experimental groups and dosing regimens for the effects of TNBS on Crohn's disease mice

[0128] Group Dosage regimen Blank group Intragastric administration of saline Model Group Intragastric administration of saline Positive control group (sulfasalazine) Intragastric administration of 0.5 g / kg sulfasalazine NCTC 9343 inactivated bacteria powder group <![CDATA[Gavage with 1×10 8 Cells / mL suspension of heat-inactivated NCTC 9343 bacterial powder]]> Bacteroides fragilis Bd-312 live bacteria liquid group <![CDATA[Gavage with 1×10 8 CFU / mL live Bacteroides fragilis solution]]> Bacteroides fragilis ZY-312 live bacteria liquid group <![CDATA[Gavage with 1×10 8 CFU / mL Bacteroides fragilis live bacteria solution]]> Bacteroides fragilis ZY-312 inactivated bacteria liquid group <![CDATA[Gavage with 1×10 8 Cells / mL of heat-inactivated Bacteroides fragilis <!-- 9 -->]]> Bacteroides fragilis ZY-312 inactivated bacteria powder group <![CDATA[Gavage with 1×10 8 Cells / mL of inactivated Bacteroides fragilis powder suspension]]>

[0129] 2. Experimental Results

[0130] Table 6 Effect of Bacteroides fragilis on the survival rate of TNBS-induced CD mice

[0131]

[0132] Note: Compared with the model group, **P<0.01; compared with the positive control group, #P<0.05; compared with the Bacteroides fragilis ZY-312 inactivated bacteria solution group, + P<0.05.

[0133] The mice in the blank group survived well during the experiment without death, and the mortality rate was 0. The survival rate of mice in the model group was 50% (10 / 20). The chi-square test showed that P<0.01, indicating that the difference between the model group and the blank group was statistically significant.

[0134] The model group was compared with the drug group. The chi-square test showed that the survival rates between the model group and the drug group were not completely equal, and the difference was statistically significant. Further analysis showed that compared with the positive drug group, the Bacteroides fragilis ZY-312 inactivated bacterial liquid group, the Bacteroides fragilis ZY-312 inactivated bacterial powder group and the Bacteroides fragilis ZY-312 live bacterial liquid group had stronger therapeutic effects (P<0.05), and there was no difference between the NCTC 9343 inactivated bacterial powder group and the Bacteroides fragilis Bd-312 live bacterial liquid group (P>0.05). Compared with the Bacteroides fragilis ZY-312 inactivated bacterial liquid group, the Bacteroides fragilis ZY-312 live bacterial liquid group had weaker efficacy (P<0.05), and the Bacteroides fragilis ZY-312 inactivated bacterial powder group had equivalent efficacy (P>0.05).

[0135] In summary, live bacterial liquid, inactivated bacterial liquid and inactivated bacterial powder of Bacteroides fragilis ZY-312 can be used to replace the positive drug sulfasalazine.

[0136] Table 7 Effect of Bacteroides fragilis on DAI scores of surviving mice after TNBS-induced CD

[0137]

[0138]

[0139] Note: Compared with the model group, **P<0.01, ***P<0.001; compared with the positive control group, # P<0.05; compared with the inactivated Bacteroides fragilis ZY-312 liquid group, + P<0.05.

[0140] As shown in Table 7, compared with the blank, the DAI score of the modeling group increased to varying degrees; compared with the model group, the DAI score of the treatment group was significantly reduced, and there was a very significant difference (P<0.001). Further test and analysis showed that compared with the positive drug group, the Bacteroides fragilis ZY-312 inactivated bacterial liquid group, the Bacteroides fragilis ZY-312 inactivated bacterial powder group and the Bacteroides fragilis ZY-312 live bacterial liquid group had a strong therapeutic effect (P<0.05), and there was no difference between the NCTC 9343 inactivated bacterial powder group and the Bacteroides fragilis Bd-312 live bacterial liquid group (P>0.05). Compared with the Bacteroides fragilis ZY-312 inactivated bacterial liquid group, the Bacteroides fragilis ZY-312 live bacterial liquid group had a weaker therapeutic effect (P<0.05), and the Bacteroides fragilis ZY-312 inactivated bacterial powder group had a comparable therapeutic effect (P>0.05).

[0141] Table 8 Effect of Bacteroides fragilis on serum IL-6 and IL-10 in surviving mice after TNBS-induced CD

[0142] Group IL-6 IL-10 Blank group <![CDATA[103.55±0.85 * ]]> <![CDATA[341.60±4.02 *** ]]> Model Group 261.90±7.62 87.80±1.07 Positive control group (sulfasalazine) <![CDATA[158.91±2.11 ** ]]> <![CDATA[225.97±4.86 ***+ ]]> NCTC 9343 inactivated bacteria powder group <![CDATA[140.40±1.58 **# ]]> <![CDATA[225.85±3.18 ***+ ]]> Bacteroides fragilis Bd-312 live bacteria liquid group <![CDATA[145.97±2.98 **# ]]> <![CDATA[220.17±4.28 ***+ ]]> Bacteroides fragilis ZY-312 live bacteria liquid group <![CDATA[123.02±4.35 **#+ ]]> <![CDATA[242.47±4.84 ***#+ ]]> Bacteroides fragilis ZY-312 inactivated bacteria liquid group <![CDATA[110.17±3.56 ** ]]> <![CDATA[253.57±3.79 ***# ]]> Bacteroides fragilis ZY-312 inactivated bacteria powder group <![CDATA[117.95±1.65 ** ]]> <![CDATA[260.72±4.83 ***# ]]>

[0143] Note: Compared with the model group, ** P<0.01, *** P<0.001, compared with the positive control group, # P<0.05; compared with the inactivated Bacteroides fragilis ZY-312 liquid group, + P<0.05.

[0144] As shown in Table 8, compared with the blank group, the expression level of IL-6 in the modeling group increased, and the expression level of IL-10 decreased; compared with the model group, the expression level of IL-6 in the treatment group decreased (P<0.01), and the expression level of IL-10 increased (P<0.001). Further test and analysis showed that compared with the positive drug group, the Bacteroides fragilis ZY-312 inactivated bacterial liquid group, the Bacteroides fragilis ZY-312 inactivated bacterial powder group, and the Bacteroides fragilis ZY-312 live bacterial liquid group had a strong therapeutic effect (P<0.05), and there was no difference between the NCTC 9343 inactivated bacterial powder group and the Bacteroides fragilis Bd-312 live bacterial liquid group (P>0.05). Compared with the Bacteroides fragilis ZY-312 inactivated bacterial liquid group, the Bacteroides fragilis ZY-312 live bacterial liquid group had a weaker therapeutic effect (P<0.05), and the Bacteroides fragilis ZY-312 inactivated bacterial powder group had a comparable therapeutic effect (P>0.05).

[0145] Example 6 Effect of inactivated Bacteroides fragilis on rats with ulcerative colitis

[0146] 1. Experimental Design

[0147] 80 SPF male SD rats with a body weight of (180±10) g were selected. After one week of adaptation, the rats were randomly divided into a blank group of 10 and a modeling group of 70. They were randomly divided into a model group, a positive control group, a NCTC 9343 inactivated bacterial powder group, a Bacteroides fragilis Bd-312 live bacterial liquid group, and a Bacteroides fragilis live bacterial liquid, inactivated bacterial liquid and inactivated bacterial powder group, with 10 mice in each group. The model group was anesthetized with pentobarbital (35 mg / kg), and the syringe was inserted from the anus to 8 cm from the anus, and 0.8 mL of TNBS (trinitrobenzene sulfonic acid) (2.0 mg / mL) containing 50% ethanol was slowly injected. The normal group was treated with an equal amount of normal saline enema. Grouping and drug treatment began 5 days after modeling.

[0148] The rats were divided into groups and given medication according to Table 9, once a day for 7 consecutive days. The behavioral characteristics and clinical symptoms of the rats were observed and recorded. After the end of the medication, the rats were fasted for 24 hours and blood was collected from the abdominal aorta. The rats were killed by cervical dislocation, and colon tissue was collected 8 cm away from the anus to observe the pathological changes of mucosal injury tissue.

[0149] The experimental results were analyzed using SPSS 25.0 statistical software. The measurement data were expressed as mean ± standard deviation (x ± s). One-way ANOVA was used for comparison among multiple groups, and LSD test was used for pairwise comparison of means among groups.

[0150] Table 9 Experimental groups and dosing regimens for the effects of TNBS on ulcerative colitis in rats

[0151] Group Dosage regimen Blank group Intragastric administration of saline Model Group Intragastric administration of saline Positive control group Mesalazine 10 mL / kg NCTC 9343 inactivated bacteria powder group <![CDATA[intragastric administration of 5×10 8 Cells / mL suspension of heat-inactivated NCTC 9343 bacterial powder]]> Bacteroides fragilis Bd-312 live bacteria liquid group <![CDATA[Gavage with 5×10 8 CFU / mL live Bacteroides fragilis suspension]]> Bacteroides fragilis ZY-312 live bacteria liquid group <![CDATA[Gavage with 5×10 8 CFU / mL live Bacteroides fragilis solution]]> Bacteroides fragilis ZY-312 inactivated bacteria liquid group <![CDATA[Gavage with 5×10 8 Cells / mL of heat-inactivated Bacteroides fragilis]]> Bacteroides fragilis ZY-312 inactivated bacteria powder group <![CDATA[Gavage with 5×10 8 Cells / mL inactivated suspension of Bacteroides fragilis]]>

[0152] 2. Experimental results:

[0153] Table 10 Effect of Bacteroides fragilis on diarrhea scores in SD rats with ulcerative colitis

[0154]

[0155]

[0156] Note: Compared with the model group, ***P<0.001, compared with the positive control group, # P<0.05; compared with the inactivated Bacteroides fragilis ZY-312 liquid group, + P<0.05.

[0157] As shown in Table 10, compared with the blank group, the model group had a significant decrease in body weight; compared with the model group, the treatment group had a slight recovery in body weight, and there was a very significant difference (P<0.001); compared with the blank group, the diarrhea score in the modeling group was significantly increased; compared with the model group, the diarrhea in the treatment group was significantly reduced, and there was a very significant difference (P<0.001). Further test and analysis showed that compared with the positive drug group, the Bacteroides fragilis ZY-312 inactivated bacterial liquid group, the Bacteroides fragilis ZY-312 inactivated bacterial powder group, and the Bacteroides fragilis ZY-312 live bacterial liquid group had a strong therapeutic effect (P<0.05), and there was no difference between the NCTC 9343 inactivated bacterial powder group and the Bacteroides fragilis Bd-312 live bacterial liquid group (P>0.05). Compared with the inactivated Bacteroides fragilis ZY-312 liquid group, the therapeutic effect of the live Bacteroides fragilis ZY-312 liquid group was weaker (P<0.05), while the therapeutic effect of the inactivated Bacteroides fragilis ZY-312 powder group was equivalent to that of the live Bacteroides fragilis ZY-312 liquid group (P>0.05).

[0158] Table 11 Effect of Bacteroides fragilis on IL-10 in SD rats with ulcerative colitis

[0159] Group IL-10 Blank group <![CDATA[340.81±4.74 *** ]]> Model Group 85.76±3.40 Positive control group (mesalazine) <![CDATA[222.31±5.01 ***+ ]]> NCTC 9343 inactivated bacteria powder group <![CDATA[220.69±4.62 ***+ ]]> Bacteroides fragilis Bd-312 live bacteria liquid group <![CDATA[218.65±3.12 ***+ ]]> Bacteroides fragilis ZY-312 live bacteria liquid group <![CDATA[243.88±4.42 ***#+ ]]> Bacteroides fragilis ZY-312 inactivated bacteria liquid group <![CDATA[261.02±5.10 ***# ]]> Bacteroides fragilis ZY-312 inactivated bacteria powder group <![CDATA[261.61±4.88 ***# ]]>

[0160] Note: Compared with the model group, ***P<0.001, compared with the positive control group, #P<0.05; compared with the inactivated Bacteroides fragilis ZY-312 liquid group, + P<0.05.

[0161] As shown in Table 11, compared with the blank, the expression level of IL-10 in the modeling group was reduced; compared with the model group, the expression level of IL-10 in the treatment group was increased, with a significant difference (P<0.001). Further test and analysis showed that compared with the positive drug group, the Bacteroides fragilis ZY-312 inactivated bacterial liquid group, the Bacteroides fragilis ZY-312 inactivated bacterial powder group and the Bacteroides fragilis ZY-312 live bacterial liquid group had a strong therapeutic effect (P<0.05), and there was no difference between the NCTC 9343 inactivated bacterial powder group and the Bacteroides fragilis Bd-312 live bacterial liquid group (P>0.05). Compared with the Bacteroides fragilis ZY-312 inactivated bacterial liquid group, the Bacteroides fragilis ZY-312 live bacterial liquid group had a weaker therapeutic effect (P<0.05), and the Bacteroides fragilis ZY-312 inactivated bacterial powder group had a comparable therapeutic effect (P>0.05).

[0162] The above is an explanation of the embodiments of the present invention. However, the present invention is not limited to the above embodiments. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. Use of Bacteroides fragilis in preparing a product for improving and / or treating enteritis, wherein the Bacteroides fragilis is a killed bacterium; The Bacteroides fragilis is selected from Bacteroides fragilis ZY-312 and Bacteroides fragilis NCTC9343 with a deposit number of CGMCC No. 10685; Preferably, the enteritis includes non-infectious enteritis and colitis.

2. The use according to claim 1, characterized in that: The non-infectious enteritis includes radiation enteritis and allergic colitis; and / or, the colitis includes Crohn's disease and ulcerative colitis; Preferably, the radiation enteritis is radiation colitis caused by X-rays; And / or, the allergic colitis is diet-induced idiopathic colitis.

3. The use according to claim 1 or 2, characterized in that: The inactivated bacteria are morphologically intact inactivated bacteria and / or morphologically incomplete inactivated bacteria; Preferably, the inactivated bacteria are inactivated by any one or more of dry heat, moist heat, filtration, organic solvents, chemical reagents, ultraviolet or infrared rays, fermentation, freeze drying, genetic recombination, genetic modification or transformation.

4. The use according to any one of claims 1 to 3, characterized in that: The inactivated bacteria is inactivated Bacteroides fragilis powder; Preferably, the preparation method of the inactivated Bacteroides fragilis powder is as follows: fermenting and culturing Bacteroides fragilis and centrifuging to obtain bacterial cells, washing the bacterial cells with a sodium chloride aqueous solution and centrifuging to obtain washed bacterial cells, adding an excipient to resuspend, inactivating and centrifuging to obtain inactivated bacterial sludge, and drying; Further preferably, the preparation method of the inactivated Bacteroides fragilis powder is as follows: (1) fermenting Bacteroides fragilis, centrifuging the fermentation broth after the fermentation is completed, and collecting the bacterial cells; (2) adding sodium chloride aqueous solution at a weight volume ratio of 1 g of bacterial cells to sodium chloride aqueous solution (10-30) mL) for washing, and centrifuging to obtain washed bacterial cells; (3) adding the first excipient solution to the washed bacterial cells, mixing and resuspending to obtain a bacterial cell solution, then performing an inactivation treatment, centrifuging, and collecting the inactivated bacterial sludge; (4) adding a second excipient solution to the inactivated bacteria sludge obtained in step (3) to obtain an inactivated bacteria stock solution; (5) Drying the inactivated bacteria stock solution obtained in step (4) until the residual moisture is less than 5 wt %, thereby obtaining inactivated Bacteroides fragilis bacteria powder.

5. The use according to any one of claims 1 to 3, characterized in that: The inactivated bacteria is a suspension of inactivated bacteria powder; Preferably, the preparation method of the inactivated bacterial powder suspension is as follows: fermenting and culturing Bacteroides fragilis and centrifuging to obtain bacterial cells, washing the bacterial cells with a sodium chloride aqueous solution and centrifuging to obtain washed bacterial cells, adding an excipient to resuspend, inactivating and centrifuging to obtain inactivated bacterial mud, drying to obtain inactivated bacterial powder, and stirring the inactivated bacterial powder with water to prepare the inactivated bacterial powder suspension; Further preferably, the preparation method of the inactivated bacteria powder suspension is as follows: (1) fermenting Bacteroides fragilis, centrifuging the fermentation broth after the fermentation is completed, and collecting the bacterial cells; (2) adding sodium chloride aqueous solution at a weight volume ratio of 1 g of bacterial cells to sodium chloride aqueous solution (10-30) mL) for washing, and centrifuging to obtain washed bacterial cells; (3) adding the first excipient solution to the washed bacterial cells, mixing and resuspending to obtain a bacterial cell solution, then performing an inactivation treatment, centrifuging, and collecting the inactivated bacterial sludge; (4) adding a second excipient solution to the inactivated bacteria sludge obtained in step (3) to obtain an inactivated bacteria stock solution; (5) drying the inactivated bacteria stock solution obtained in step (4) until the residual moisture content is less than 5 wt %, thereby obtaining inactivated Bacteroides fragilis bacteria powder; (6) Add water to the inactivated bacteria powder obtained in step (5) in a mass ratio of bacteria powder to water = 1: (2-5), stir with a stirrer, and prepare an inactivated bacteria powder suspension.

6. The use according to claim 4 or 5, characterized in that: In step (1), the bacterial count of the fermentation liquid reaches 10 8 CFU / mL or above; And / or, in step (2), the mass concentration of the sodium chloride aqueous solution is 0.6-1.5wt%, preferably 0.65-1.2wt%, more preferably 0.8-1.0wt%, most preferably 0.85-0.95wt%, for example, 0.9wt% sodium chloride aqueous solution; and / or, the first excipient in step (3) is the same as or different from the second excipient in step (4), and is independently selected from at least one of mannitol, sorbitol, maltodextrin, lactose, sodium chloride, maltose, sucrose, glucose, trehalose, dextran, proline, lysine, alanine, casein, and skim milk; and / or, in step (3), the weight volume ratio of the bacterial cells to the first excipient solution is 1 g: (5-40) mL; and / or, in step (3) and / or step (4), the mass fraction of the excipient is 4 to 30 wt %; and / or, in step (3) and / or step (4), the excipient solution is selected from a sodium chloride aqueous solution; preferably, the excipient solution is selected from a physiological saline solution, such as a 0.9 wt % sodium chloride aqueous solution; And / or, in step (3), the inactivation method is selected from at least one of heat inactivation, freeze inactivation or chemical inactivation, preferably heat inactivation; illustratively, the heat inactivation temperature is 60 to 100° C., and the heat inactivation time is 10 to 60 min; and / or, in step (4), adding a second excipient solution so that the total weight of the inactivated bacteria stock solution is consistent with the weight of the bacterial solution before inactivation in step (3); and / or, the second excipient solution is the same as the first excipient solution; And / or, in step (5), the drying method is selected from vacuum freeze drying and spray drying, preferably vacuum freeze drying; preferably, the conditions of the vacuum freeze drying include: a freezing temperature of -20 to -40°C, a freezing time of 1 to 3 hours, and a vacuum degree of 0.20 to 0.25 mbar; illustratively, the vacuum freeze drying process includes: pre-freezing at -40±2°C for 1 to 3 hours, pre-freezing at -20±2°C for 0.5 to 1 hour, and finally freezing at -40±2°C for 0.5 to 2 hours, and preparing the inactivated bacteria powder by primary drying and analytical drying under a vacuum degree of 0.25 mbar; And / or, in step (6), the agitator is stirred at 500-1000 rpm for 10-30 min until no particles are visible to the naked eye in the suspension; And / or, in step (6), the bacterial cell concentration is prepared to be 2×10 10 Cells / g or above inactivated bacteria powder suspension.

7. The use according to any one of claims 1 to 6, characterized in that: The product may be any of a pharmaceutical composition, a food, a health product or a food additive; Preferably, the pharmaceutical composition contains a pharmaceutically effective dose of inactivated Bacteroides fragilis ZY-312 powder with a deposit number of CGMCC No. 10685; Preferably, the pharmaceutically effective dose is 10 7 -10 9 Cells / mL. Preferably, the dosage form of the pharmaceutical composition is pills, tablets, granules, capsules, powders, suspensions, oral solutions or enema; Preferably, the pharmaceutical composition is administered orally or by enema. Preferably, the administration cycle of the pharmaceutical composition is intermittent administration, periodic administration, continuous administration or long-term administration.

8. Use of Bacteroides fragilis in preparing a product for improving and / or treating non-infectious enteritis, wherein the Bacteroides fragilis is a live bacterium; the Bacteroides fragilis is Bacteroides fragilis ZY-312 with a deposit number of CGMCC No. 10685; Preferably, the non-infectious enteritis includes radiation enteritis and allergic colitis. Preferably, the radiation enteritis is radiation colitis caused by X-rays; And / or, the allergic colitis is diet-induced idiopathic colitis.

9. The use according to claim 8, characterized in that: The product may be any of a pharmaceutical composition, a food, a health product or a food additive; Preferably, the dosage form of the pharmaceutical composition is pills, tablets, granules, capsules, powders, suspensions, oral solutions or enema; Preferably, the pharmaceutical composition is administered orally or by enema; Preferably, the administration cycle of the pharmaceutical composition is intermittent administration, periodic administration, continuous administration or long-term administration.

Images