Bifidobacterium lactis and use thereof for the preparation of products for the prevention and / or treatment of obesity and / or weight loss

Abstract

The present application belongs to the technical field of microbial inoculants, and particularly relates to a Bifidobacterium lactis, and further discloses a use of the Bifidobacterium lactis in preparation of an anti-obesity product and / or a weight loss product. A YG2013 strain is screened from healthy adult feces, and is identified as the Bifidobacterium lactis and classified as Bifidobacterium lactis. According to experimental identification, the Bifidobacterium lactis YG2013 strain can realize white adipose beige and activate brown adipose metabolism heat production through targeted regulation of tgr5 / Il-27, so as to achieve the effect of efficient weight loss, and has a good effect of treating weight loss and weight loss.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of microbial agents, and specifically relates to a Bifidobacterium lactis, and further discloses the use of the Bifidobacterium lactis in preparing an anti-obesity product and / or a weight loss product. BACKGROUND

[0002] According to the Report on the Status of Nutrition and Chronic Diseases Among Chinese Residents (2020), the rate of overweight and obesity among Chinese residents continues to rise, among which, the rate of overweight and obesity among adult residents is over 50%, and the rate of overweight and obesity among children and adolescents aged 6-17 and under 6 is 19% and 10.4%, respectively. It is reported that overweight or obesity can significantly increase the risk of type 2 diabetes, hypertension, non-alcoholic fatty liver, cardiovascular disease and cancer, and has become a potential hidden danger affecting the health of residents, posing a major challenge to human health. It can be seen that overweight or obesity has become a global public health problem.

[0003] It has been shown by research that overweight or obesity is mainly due to the imbalance between energy intake and consumption. At present, the main anti-obesity strategy is to limit energy intake and absorption through weight loss drugs. However, these drugs not only have great side effects, but some even have hepatotoxicity, for example, Orlistat is prone to cause diarrhea, endocrine disorders, insomnia and other adverse reactions during medication, and there is a situation of regaining weight after stopping the drug. Therefore, it is expected in the field to find natural and safe drugs or functional foods to achieve the purpose of treating obesity.

[0004] Brown adipose tissue (BAT) is a highly metabolically active tissue that contains a large number of mitochondria, which increases the conductivity of the mitochondrial inner membrane by highly expressing uncoupling protein 1 (ucp1), thereby inducing BAT mitochondria to generate heat. The process of white adipose tissue turning into beige adipose tissue is the browning of white adipose tissue, and beige adipocytes have similar morphology and function to BATs, and can utilize lipids and blood glucose, thereby improving blood lipid and glucose metabolism. At present, by activating BAT activity and promoting the formation of beige adipose tissue, it has become an attractive method to increase energy consumption to combat diet-induced obesity and related metabolic diseases.

[0005] More and more evidence shows that there is a close relationship between the intestinal microbiome and obesity, and the intestinal microbiota has the effect of regulating the phenotype and function of adipocytes. Therefore, it is a new effective treatment method for preventing and treating obesity to find a natural and safe drug or food capable of regulating the intestinal microbiota, so as to activate the metabolic heat production by up-regulating BAT and ucp1 in brown adipose tissue. A large number of studies have proved that probiotics have been proved to be able to improve obesity and its related metabolic disorders, mainly in promoting intestinal peristalsis, preventing constipation and the like. However, the abundance of traditional probiotics in the human body is low, and the individual difference is large, and the existing probiotic products have no obvious regulation on the intestinal flora and the mechanism is single, resulting in a long time for weight loss and an unsatisfactory product effect. SUMMARY

[0006] Therefore, the technical problem to be solved by the present application is to provide a lactobacillus bifidus with the effect of promoting the whitening of brown adipose tissue, which can reduce the inflammation of white adipose tissue and induce the remodeling of brown adipose tissue, so as to achieve the effect of resisting obesity.

[0007] The second technical problem to be solved by the present application is to provide the use of the above-mentioned lactobacillus bifidus for preparing a product for preventing or treating obesity and / or weight loss.

[0008] To solve the above technical problems, the present application discloses a lactobacillus bifidus with the effect of promoting the whitening of brown adipose tissue, which can reduce the inflammation of white adipose tissue and induce the remodeling of brown adipose tissue, so as to achieve the effect of resisting obesity. tgr5 Il-27 The use of a regulatory agent with the effect of regulating the targeted regulation of the pathway for preparing a product with the effect of weight loss and weight reduction; wherein,

[0009] The regulatory agent is based on the targeted regulation of the pathway, tgr5 Il-27 promoting the whitening of white adipose tissue and reducing its inflammatory effect, and activating the metabolic heat production of brown adipose tissue and reducing its inflammatory effect.

[0010] The present application also discloses the use of a preparation with the effect of improving the intestinal flora characteristic of obesity for preparing a product with the effect of weight loss and weight reduction; wherein,

[0011] The improvement of the intestinal flora includes increasing the abundance of beneficial bacteria and / or reducing the abundance of harmful bacteria;

[0012] Preferably, the improvement of the intestinal flora includes increasing the abundance of uncultured bacteria, f_Lachnospiraceae, Duncaniella, Lactobacillus, Limosilactobacil and Eubacterium improving the production of SCFAs;

[0013] Preferably, the improvement of the intestinal flora includes increasing the abundance of beneficial bacteria, unclassified_f_Lachnospiraceae , Duncaniella , Lactobacillus , Eubacterium ​​Abundance of the flora, reducing harmful bacteria Ileibacterium 、 Vampirovibrio 、 Clostridium Abundance of the flora.

[0014] The present application discloses a Bifidobacterium lactis YG2013, which is classified as Bifidobacterium lactis Bifidobacterium lactis , and has been preserved in the China General Microbiological Culture Collection Center on June 7, 2023, with a preservation number of CGMCC No. 27579.

[0015] The present application also discloses the use of the Bifidobacterium lactis YG2013 and its inactivated substances and metabolites for preparing a probiotic preparation.

[0016] The present application also discloses a probiotic preparation, wherein the active ingredients of the probiotic preparation include the bacterial bodies of the Bifidobacterium lactis YG2013 and its inactivated substances and / or metabolites.

[0017] Specifically, in the probiotic preparation, the effective bacterial body quantity of the Bifidobacterium lactis YG2013 is 5.0×10 9 -1.0×10 11 CFU / day / person.

[0018] Specifically, the probiotic preparation includes at least one of a powder, a granule, a pill, a capsule, a tablet, a paste, a liquid preparation, a gel, a spray or a solid beverage.

[0019] The present application also discloses a method for preparing the probiotic preparation, which includes the steps of culturing the bacterial bodies of the Bifidobacterium lactis YG2013, and processing the selected dosage form according to the conventional process and by adding conventional excipients.

[0020] The present application also discloses the use of the Bifidobacterium lactis YG2013 and its inactivated substances and metabolites or the probiotic preparation for preparing a functional product having at least one of the following (1)-(10) effects:

[0021] (1) preventing and treating obesity;

[0022] (2) having a weight loss effect;

[0023] (3) remodeling the whitish fat into beige fat;

[0024] (4) activating brown fat metabolism to generate heat;

[0025] (5) targeting the regulation of the tgr5 / Il-27 pathway;

[0026] (6) reducing inflammation of white adipose tissue;

[0027] (7) Alleviates hepatocyte steatosis and inflammatory response;

[0028] (8) It produces a variety of short-chain fatty acids, which regulate energy metabolism;

[0029] (9) Increase the number of unsorted animals by cross-feeding. f_Lachnospiraceae, Duncaniella, Lactobacillus, Limosilactobacil and Eubacterium The abundance of the microbial community increases the yield of SCFAs;

[0030] (10) Targeted improvement of the characteristic gut microbiota of obesity and enhancement of beneficial bacteria unclassified_f_ Lachnospiraceae , Duncaniella , Lactobacillus , Eubacterium Increase the abundance of bacterial flora and reduce harmful bacteria. Ileibacterium , Vampirovibrio , Clostridium Increase the abundance of gut microbiota and restore the health of the gut microbiota.

[0031] Specifically, the functional products include pharmaceuticals.

[0032] The present invention also discloses a probiotic preparation with white fat beige remodeling function, wherein the active ingredients of the probiotic preparation include the aforementioned Bifidobacterium lactis YG2013 and its inactivated products and / or metabolites.

[0033] Preferably, the effective bacterial count of the Bifidobacterium lactis YG2013 is 1.0 × 10⁻⁶. 10 -5.0×10 10 CFU / day / person.

[0034] The present invention also discloses a probiotic preparation with weight loss effect, wherein the active ingredients of the probiotic preparation include the aforementioned Bifidobacterium lactis YG2013 and its inactivated products and / or metabolites;

[0035] Preferably, the effective bacterial count of the Bifidobacterium lactis YG2013 is 2.0 × 10⁻⁶. 10 -8.0×10 10 CFU / day / person.

[0036] This invention obtained a strain YG2013 from the feces of healthy adults, which was identified as Bifidobacterium lactis and classified as such. Bifidobacterium lactis Experimental identification showed that the Bifidobacterium lactis strain YG2013 can be targeted and regulated. tgr5 / Il-27 It achieves efficient weight loss by turning white fat into beige and activating the metabolic heat production of brown fat, and has a good therapeutic effect on weight loss.

[0037] The strain disclosed by the application first discovers and verifies that the Bifidobacterium lactis has a targeted regulation on the pathway tgr5 / Il-27 , has a role in promoting beige of white adipose tissue, thereby realizing beige of white adipose tissue and activation of brown adipose tissue metabolic heat production, further playing a role in reducing inflammation of white adipose tissue and inducing beige remodeling, realizing anti-obesity effect, and realizing the effect of efficient weight loss.

[0038] The strain disclosed by the application first discovers and verifies that the Bifidobacterium lactis has a targeted regulation on the pathway Il-27 , thereby playing a role in reducing inflammation of brown adipose tissue and activating metabolic heat production, realizing anti-obesity effect.

[0039] The Bifidobacterium lactis YG2013 disclosed by the application is verified by experiments to have a role in playing efficient weight loss through differential new target points. The Bifidobacterium lactis YG2013 disclosed by the application plays a role in improving high-fat high-sugar disorder through a comprehensive mechanism, and the specific performance is as follows:

[0040] a, targeted regulation tgr5 / Il-27 pathway, promoting beige of white adipose tissue and reducing inflammation effect thereof;

[0041] b, targeted regulation Il-27 pathway, activating metabolic heat production of brown adipose tissue and reducing inflammation effect thereof;

[0042] c, relieving hepatocyte steatosis and inflammation reaction;

[0043] d, producing various short-chain fatty acids to regulate energy metabolism;

[0044] e, targeted improvement of intestinal flora characteristic of obesity, increase of abundance of beneficial bacteria, decrease of abundance of harmful bacteria, and recovery of health of intestinal flora.

[0045] The Bifidobacterium lactis YG2013 disclosed by the application is a new generation of probiotic agent, and can be prepared into a probiotic agent according to a conventional mode based on the Bifidobacterium lactis YG2013 as an active ingredient, thereby not only solving the problem of many side effects existing in the current drug weight loss mode, but also effectively solving the defects of low abundance of the current traditional probiotic product in the human body and large individual difference affecting the efficacy of the product.

[0046] The probiotic preparation for preventing and treating obesity and / or weight loss and weight reduction disclosed by the application has an active ingredient including the Bifidobacterium lactis YG2013, inactivates and / or metabolites thereof, can select to add other active ingredients, or only use the Bifidobacterium lactis YG2013 as an active ingredient, utilize the active effect of the Bifidobacterium lactis YG2013, play a role in weight loss, fat reduction and weight reduction, and has the advantages of safe medication and significant improvement effect. Attached Figure Description

[0047] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings, wherein...

[0048] Figure 1 The results show the cholesterol-degrading ability of the strain described in Example 2.

[0049] Figure 2 The results are the detection results of bile salt hydrolase activity of the strain described in Example 3;

[0050] Figure 3 The results of the tolerance test of the strain described in Example 4 to the simulated gastrointestinal environment;

[0051] Figure 4 The results of the SCFAs production capacity test of the strain described in Example 5;

[0052] Figure 5 The results of the cell adhesion ability test of the strain described in Example 6;

[0053] Figure 6 The results of the hemolytic activity test of the strain described in Example 7;

[0054] Figure 7 The results of the YG2013 strain in Example 8 reducing weight gain and fat accumulation in HFD mice;

[0055] Figure 8 The results of YG2013 strain in Example 8 reducing inflammation and inducing beige remodeling of eWAT;

[0056] Figure 9 The results of the YG2013 strain in Example 8 reducing inflammation and activating the thermogenic activity of brown fat;

[0057] Figure 10 Example 8 shows that strain YG2013 reduced liver inflammation and improved hepatic steatosis; where A is a liver HE-stained section; B is a liver Oil Red O-stained section; C is the liver pathological score; and D is the liver gene detection result.

[0058] Figure 11 The results of the YG2013 strain intervention in HFD-fed mice showed the changes in SCFA concentrations.

[0059] Figure 12Fig. 1. The results of YG2013 changed the diversity and composition of intestinal microbiota of HFD-fed mice; A-B are Chao and Shannon, a- diversity analysis indicators, respectively; C is the PCoA plot analysis result of each sample; D is the Venn diagram result, showing the observed ASV overlap; E is the phylum level in the feces of mice; F is the bacterial community result at the family level;

[0060] Figure 13 Fig. 2. The results of YG2013 on intestinal bacterial composition; A is the analysis result of the genus level heat map; B is the LEfSe analysis (LDA>3); C-D are the Kruskal-Wallis H test bar chart at the genus level and the test chart at the species level (*p<0.05, **p<0.01, ***p<0.001);

[0061] Figure 14 Fig. 3. Correlation analysis between intestinal microbiota and obesity-related indices and pathways between groups; A is the correlation between intestinal flora and biochemical indicators; B is the correlation between intestinal flora and eWAT and BAT gene expression; C is the path predicted to have different abundances between groups according to KEGG pathway analysis. DETAILED DESCRIPTION

[0062] In the results of the following examples and drawings, the strain YG2013 can be expressed as YGMCC2013 or simply as 2013, which all represent the screening strain YG2013 of the present application, and this is hereby stated.

[0063] Example 1 Isolation and identification of the strain

[0064] 1. Isolation of Bifidobacterium lactis

[0065] Sample source

[0066] The strain used in this example was isolated from the feces of healthy adults.

[0067] Isolation and screening of strains

[0068] 1g of the fecal sample was placed in 9mL of PBS buffer (LQQiao, CM1022), vortexed and mixed, then diluted with sterile normal saline in ten-fold gradient, and 10 -6 , 10 -7 , 10 -8Three dilution gradients, each gradient takes 100 μL of diluent evenly coated on MRS medium (Land Bridge, CM188) + 0.03% L-cysteine hydrochloride (Land Bridge, P-63) agar medium, i.e. mMRS medium, at 37°C anaerobic culture for 48h to have obvious single colony formation, then pick the colonies to continue to purify on the mMRS plate for more than 3 times until the colony morphology on the plate is consistent.

[0069] 2. Identification of Bifidobacterium lactis

[0070] Colony characteristics

[0071] The screened strain is cultured on mMRS medium for 24-48h, the diameter is between 0.5-1.0mm, the colony is milky white, and the surface is smooth, which is named YG2013.

[0072] 16S rRNA gene sequencing

[0073] The screened Bifidobacterium lactis strain is sent to Shanghai Shengong for 16S rRNA gene sequencing, and the 16S rRNA gene sequence of Bifidobacterium lactis strain 2013 is shown as SEQ ID No. 1.

[0074]

[0075] The 16S rRNA sequence results were subjected to BLAST comparison on the NCBI database (https: / / blast.ncbi.nlm.nih.gov / Blast.cgi), combined with the morphological characteristics of the strains, and the screening strain YG2013 was preliminarily determined as Bifidobacterium lactis (Bifidobacterium lactis). Bifidobacterium lactis )。

[0076] The Bifidobacterium lactis YG2013 screened in this example is classified and named as Bifidobacterium lactis Bifidobacterium lactis , which is preserved in the General Microbiological Center of the Chinese Microorganism Strain Preservation Management Committee (CGMCC for short, address: No. 3, Beichen West Road, Chaoyang District, Beijing, Institute of Microbiology of Chinese Academy of Sciences, postcode: 100101), with the preservation number CGMCC No. 27579 and the preservation date June 7, 2023.

[0077] Example 2

[0078] In this example, the ability of the strain to reduce cholesterol in vitro was detected based on HPLC method.

[0079] Cholesterol powder medium preparation: take cholesterol 0.2 g, Tween-80 2.0 mL, sucrose ester 0.2 g, and ice acetic acid 10.0 mL, mix, filter sterilization after ultrasonic (10 min, 20% power) to obtain cholesterol emulsion (16.7 mg / ml). Add the prepared cholesterol emulsion above to the mMRS medium after dispensing to make the final concentration 0.1 mg / mL. The activated strain was inoculated in the amount of OD=1.0, 4×10 7 CFU in the cholesterol medium (200 μl into 1.8 mL culture system). The uninfected test tube was used as a blank control. Incubate at 37°C for 48 h, centrifuge and store the supernatant at -80°C.

[0080] Liquid phase detection: sample pretreatment: filter through 0.22 μm organic filter membrane, filter liquid is moved into the on-machine vial for use, for high performance liquid chromatography analysis. Detection conditions: chromatographic column: C18 reversed phase chromatographic column (4.6 mm×150 mm, 5 μm); mobile phase: 100% methanol (V / V, analytical pure), B tube; detection wavelength: 205 nm; flow rate: 2.0 mL / min; column temperature: 40°C; injection volume 5 μL.

[0081] Cholesterol degradation rate = (Ac-As) / Ac x 100%;

[0082] In the formula, Ac is the initial cholesterol concentration of the culture solution; As is the residual cholesterol concentration in the culture solution after culture.

[0083] In this embodiment, the above-mentioned in vitro cholesterol degradation method is used to select five different bifidobacteria for screening probiotics with anti-obesity potential, and the results are shown in the accompanying Figure 1

[0084] As shown in the results in the accompanying Figure 1 Among the experimental strains, Bifidobacterium lactis YG2013 and Bifidobacterium breve YGMCC2007 have significantly higher cholesterol degradation activity than Lactobacillus rhamnosus GG (16.37%); among them, YGMCC2007 and YG2013 have higher cholesterol degradation activity, reaching 28.28% and 23.26%, respectively. It can be seen that the screening strain YG2013 of the present application has high cholesterol degradation activity and is a bifidobacterium with anti-obesity potential, and further analysis of its probiotic properties is needed.

[0085] Example 3

[0086] In this embodiment, the HPLC method is used to detect the enzyme activity of the screening strain BSH and evaluate its ability to degrade bile salts.

[0087] pH 5.0 0.1M HAc-NaAc buffer preparation: take 14.8mL 0.2M HAc + 35.2mL 0.2M NaAc, add water to 100mL.

[0088] The activated strain is inoculated into MRS or BHIS liquid medium at an inoculation amount of 1% (v / v) v / v ) and cultured overnight to measure the OD600 value. Each strain is adjusted to OD=1 (the fermentation broth needs to be cultured in advance, about 20ml), centrifuged, the supernatant is discarded, the bacterial cells are washed once with 0.1M HAcNaAc buffer (pH 5.0), and the bacterial cells are resuspended in an equal volume. After mixing 400μL of bacterial suspension and 400μL of 20mM bile salt mixture (TDCA+GDCA), 37℃ water bath for 1h. The control sample is a mixture of 400μL of 20mM bile salt mixture and 400μL of HAcNaAc buffer. After water bath, add 800μL of 15% TCA termination solution to terminate the reaction, mix well, centrifuge and take the supernatant to store at -80°.

[0089] ​Liquid Chromatography (HPLC) Detection: Sample Pretreatment: Filter the supernatant through a 0.22µm nylon membrane. Transfer the filtrate to a vial for use in HPLC analysis. Detection Conditions: Column: Agilent TC-18 C18 reversed-phase column (5µm, 4.6mm × 250mm); Detector: Diode array detector; Detection wavelength: 200nm; Injection volume: 20µL; Column temperature: 30℃; Column flow rate: 1mL / min; Mobile phase B: 7.5mmol / L tetrabutylammonium bisulfate in acetonitrile-water (60:40) solution (pH 2.5); Mobile phase C: 7.5mmol / L tetrabutylammonium bisulfate in acetonitrile-water (30:70) solution (pH 2.5); Gradient elution: Mobile phase B 10%, mobile phase C 90%, with the proportion of mobile phase B increasing from 10% to 70% within 30min.

[0090] In this embodiment, using the above-described in vitro degradation method for bound bile salts, five different Bifidobacteria were selected to screen for probiotics with anti-obesity potential. The results are shown in the appendix. Figure 2 As shown.

[0091] As attached Figure 1 The results show that among the experimental strains, YG2013 exhibited the best bile salt degradation ability, achieving 100% degradation rates for both GDCA and TDCA, significantly higher than the activities of LGG (6.64% and 2.48%). All tested strains showed differences in TDCA degradation activity; YG2013's degradation ability was significantly higher than the other three Bifidobacteria, followed by YGMCC2019, while YGMCC2007 and YGMCC2031 were relatively lower, at only 11.53% and 13.69%, respectively. Therefore, the strain YG2013 screened in this invention possesses highly efficient bile salt degradation activity and is a Bifidobacterium with anti-obesity potential; further analysis of its probiotic properties is needed.

[0092] Example 4

[0093] Gastrointestinal tolerance is an important evaluation indicator for assessing the probiotic properties of bacterial strains. In this embodiment, the gastrointestinal fluid tolerance of the screened strains was tested.

[0094] Preparation of pH 3.0 artificial gastric juice: Dissolve 0.15g of pepsin in 50mL of sterile physiological saline (0.9%w / v) to a final enzyme concentration of 3g / L. Adjust the pH to 3.0 with hydrochloric acid. Filter the pepsin solution through a 0.22μm sterile filter membrane. Prepare and use immediately.

[0095] Preparation of pH 8.0 artificial colonic fluid: Dissolve 0.05g of trypsin in 50mL of sterile physiological saline (0.9%w / v) until the final enzyme concentration is 1g / L. Adjust the pH to 8.0 with NaOH solution. Filter the solution through a 0.22μm sterile membrane for sterilization. Prepare and use immediately.

[0096] Take the activated bacteria liquid, centrifuge and discard the supernatant, 0.2 mL of bacteria liquid is washed once with PBS and resuspended in 0.2 mL of PBS for gradient dilution, and the titer method is used for counting N0 (0h treatment). Another 1.2 mL of bacteria liquid is centrifuged and the supernatant is discarded, and after washing once with PBS, it is resuspended in 1.2 mL of artificial simulated gastric juice at pH 3.0, and after anaerobic culture at 37°C for 2h, 0.2 mL of bacteria liquid is taken, centrifuged and discarded, washed once with PBS and resuspended in 0.2 mL of PBS, and used for viable bacteria counting N1 (gastric juice treatment for 2h); 1 mL of bacteria liquid is washed once and resuspended in 1 mL of artificial simulated colon juice at pH 8.0, and after anaerobic culture at 37°C for 4h, the supernatant is centrifuged and discarded, and after washing once with PBS, it is resuspended in 1 mL of PBS, and after 37°C culture for 48h, the colony count N2 (intestinal juice treatment for 4h).

[0097] In this embodiment, the screening strains YG2013 and LGG are selected for gastrointestinal tolerance experiment, and the results are shown in the following table. Figure 3

[0098] As shown in the results Figure 3 , the survival rates of the screening strain YG2013 in the above-mentioned gastric juice and intestinal juice are 113.77% and 93.44% respectively, and there is no significant difference with LGG, indicating that YG2013 has similar excellent tolerance to gastrointestinal environment as LGG.

[0099] Example 5

[0100] The ability of the strain to produce SCFAs is an important evaluation index for evaluating the probiotic characteristics of the strain. In this embodiment, the content of SCFAs produced by the strain is detected based on HPLC method.

[0101] Precisely take 1.00g of lactic acid, 1.00g of acetic acid, 0.250g of propionic acid, 0.250g of butyric acid and 0.250g of succinic acid, dissolve and dilute to 10mL in a volumetric flask (lactic acid 100g / L, acetic acid 100g / L, propionic acid 25g / L, butyric acid 25g / L, succinic acid 25g / L) with appropriate amount of ultrapure water, shake well, and then dilute 1mL of each of the five standard solutions to obtain five concentration gradients (see Table 1 below). After filtration through a 0.22μm filter membrane, the acid standard control solution is obtained.

[0102] Table 1 Five concentration gradients of mixed standard

[0103]

[0104] ​Five organic acid standards were mixed and injected, and the chromatographic conditions shown in Table 2 were used for detection. The chromatographic peaks of each acid were well separated. The elution times of lactic acid, acetic acid, succinic acid, propionic acid and butyric acid were approximately 3.24, 3.53, 4.21, 6.27 and 13.84 min, respectively, indicating that the detection method can detect five organic acids simultaneously.

[0105] Table 2 Chromatographic conditions

[0106]

[0107] Note: Phosphate solution: 20 mmol / L NaH2PO4 (adjust pH to 2.7 with phosphoric acid).

[0108] Linear regression was performed with peak area as the ordinate (y) and mass concentration as the abscissa (x, g / L) to obtain the linear regression equations for lactic acid, acetic acid, propionic acid, butyric acid, and succinic acid, as shown in Table 3 below. The results show that the five organic acids have good linear relationships within the concentration range, with correlation coefficients r reaching 0.99, indicating good linearity.

[0109] Table 3 Linear Relationships of Short-Chain Fatty Acids

[0110]

[0111] In this embodiment, the ability of two bacterial strains to produce SCFAs was detected by HPLC. Strains frozen at -80℃ were transferred to the corresponding liquid culture medium and statically cultured at 37℃ under anaerobic conditions for 24-48 hours. This process was repeated for three generations. The fermentation broth from the third generation, cultured for 20 hours, was centrifuged at 11000 rpm for 1 minute at 4℃. The supernatant was filtered through a 0.22 μm filter and transferred to a liquid chromatography vial. The content of each organic acid in the MRS medium was detected using the above method. Finally, the acid production of *Bifidobacterium lactis* YG2013 and *Lactobacillus rhamnosus* LGG after 20 hours of fermentation was calculated. The results are shown in the appendix. Figure 4 .

[0112] As attached Figure 4 The results show that LGG can only produce one short-chain fatty acid—lactic acid, and the lactic acid content is as high as 139.97 mM; unlike LGG, the YG2013 strain screened in this invention can produce high levels of acetic acid (60.37 mM) while producing only a small amount of lactic acid (19.06 mM).

[0113] Example 6

[0114] Cell adhesion ability is an important evaluation indicator for assessing the probiotic properties of bacterial strains. In this embodiment, self-aggregation and hydrophobicity assays were used to evaluate the adhesion ability of two bacterial strains.

[0115] After incubation at 37°C for 18 hours, the absorbance of the Bacteroides strain in PBS at 600 nm (A0 or H0) was 0.60. In simpler terms, 4 mL of cell suspension from each strain was incubated at 20°C for 24 hours, and the absorbance of 1 mL of the upper phase was measured as the OD value at 600 nm (A1).

[0116] The formula for calculating self-aggregation capability is as follows: A (%) = (1 - A1 / A0) × 100%.

[0117] Add 1 mL of chloroform to 3 mL of cell suspension and shake for 3 min. After incubation at 37 °C for 1 h, measure at 600 nm (H1).

[0118] The hydrophobicity value is calculated as follows: H (%) = (1) (H1 / H0) × 100%.

[0119] The calculation results are attached. Figure 5 As shown, the YG2013 strain screened in this invention has a high cell surface hydrophobicity, reaching 74.16%, which is significantly higher than LGG (61.02%). However, the self-agglutination ability of the YG2013 strain is 75.23%, which is slightly lower than LGG (84.03%), indicating that the YG2013 strain screened in this invention has good cell adhesion and intestinal colonization ability.

[0120] Example 7

[0121] Hemolytic properties are an important evaluation indicator for assessing the probiotic properties of bacterial strains. In this example, Columbia blood agar plates were used to determine the hemolytic properties of three bacterial strains.

[0122] The strain was inoculated onto Columbia agar containing 5% sheep blood and incubated at 37°C for 48 hours. After incubation, hemolytic activity was assessed and classified based on the lysis of erythrocytes in the medium surrounding the colony. On Columbia blood agar plates, a clear area around the colony (β-hemolysis) and no area around the colony (γ-hemolysis) were considered normal. Only strains exhibiting γ-hemolysis were considered safe.

[0123] As attached Figure 6 The results shown are consistent with S. aureus Compared to CICC 10473 (positive reference), the YG2013 strain screened in this invention did not form any hydrolysis zone around the colony, indicating that it is a safe probiotic candidate strain.

[0124] Example 8: Study on the anti-obesity effect of Bifidobacterium lactis YG2013

[0125] Animal experimental design

[0126] Experimental animals: 40 C57BL / 6J male mice aged 7-8 weeks were purchased from Beijing Vital River Laboratory Animal Technology Co., Ltd.

[0127] Strain preparation: First, the strain YG2013 stored at -80℃ was taken out, and the obtained bacteria were activated by three generations of inoculation at a 2% inoculation amount for expansion culture. Then, the bacteria were centrifuged at a speed of 7500 rpm / min for 10-15 min, and then pre-cooled PBS was added for repeated blowing and washing. After the supernatant was discarded, the bottom bacteria were left. Finally, the pre-cooled 20% glycerol solution was added for resuspension to prepare 1.9×10 10 CFU / mL of cryopreservation solution, and immediately placed in a -80℃ refrigerator for preservation. Before gavage, the bacterial solution was diluted with PBS to the required number of viable bacteria (1×10 9 CFU / mL) for each group of gavage.

[0128] Experimental grouping: ND group (mice were fed with maintenance feed and gavaged with PBS 100ul / day / one), HFD group (mice were fed with 48.5% high-fat feed and gavaged with PBS 100ul / day / one), HFD+Orlistat group (mice were fed with 48.5% high-fat feed and gavaged with Orlistat 1.2mg / day / one), HFD+YG2013 group (mice were fed with 48.5% high-fat feed and gavaged with YG2013 bacterial solution 1×10 9 CFU / day / one).

[0129] The mice were adaptively fed for one week, and after one week, the mice in each group (except the ND group) were changed to 48.5% high-fat feed (Beijing Botai Hongda). All mice began gavage, which lasted for 8 weeks. The body weight of the mice was recorded once a week during the modeling period. At the 8th week, the feces of the mice were collected and placed in sterile EP tubes, frozen in liquid nitrogen and stored at -80℃ for fecal microbial diversity detection. After 8 weeks, the mice were fasted for 24h, and the eyeball blood was taken. After treatment, the serum was stored at -80℃. The body shape pictures of the mice in each group were taken, and the brown adipose tissue, epididymal fat, posterior abdominal wall fat, liver, cecal contents were taken out under sterile conditions, weighed and photographed. A part of each tissue was fixed with 4% cell tissue fixative and stored at room temperature. The remaining part was placed in a cryogenic tube and stored at -80℃.

[0130] Determination method

[0131] 1. Pathological detection

[0132] Fixed livers, epididymal fat, and brown fat were embedded in paraffin, 5 mm sections were cut, hematoxylin and eosin (H&E) stained, and the stained slides were observed under an optical microscope. Frozen liver samples were processed on a cryostat, fixed, and subjected to oil red O staining. The liver was evaluated for hepatocyte steatosis and inflammatory infiltrates using the following criteria. Criteria for hepatocyte steatosis: hepatic steatosis (0-3 points, <5%, 5-33%, 33-66%, >66% of parenchymal cells / total cells), lobular inflammation (0-3 points, <2, 2-4, >4 lesions per 200x field), hepatocyte ballooning (0-2 points, no change, few ballooned cells, many ballooned cells / protrusions). White fat was measured for cell maximum diameter using software randomly in 10 fields per slide.

[0133] 2. Fecal microbiota determination and analysis

[0134] Fresh feces of mice were taken in sterile EP tubes, frozen in liquid nitrogen, and stored at -80°C. Genomic DNA was extracted, and the dominant species in the samples were analyzed by 16S rRNA high-throughput sequencing technology to obtain the composition of the microbial community in the samples and the relative abundance differences between them.

[0135] 3. Gene detection

[0136] Total RNA was extracted from the liver, epididymal fat, and brown fat using the Total RNA Extraction Kit from Qiagen. The extraction process for the liver was performed according to the instructions, and for the adipose tissue, 4°C, 12000 rpm centrifugation for 10 min was required after Trizol lysis, which improved the purity of the extracted RNA.

[0137] Takara reverse transcription kit was used for reverse transcription to obtain cDNA samples, and the qPCR detection was performed using the Fast Fluorescent Quantitative PCR Reagent Kit from Tiangen and the Fluorescent Quantitative PCR Amplifier (Roche® 480). The primers are shown in Table 4 below. The detection indexes include thermogenic-related factors tgr5, dio2, Il-27, Il-27ra, elovl3, prdm16, ucp1, pparα, pgc1α ; pro-inflammatory factors Il-1β, tnf- α, Il-6, Il-8 ; anti-inflammatory factors Il-4, foxp3 .

[0138] Table 4 qPCR primers

[0139]

[0140] 4. Cecal content SCFAs detection

[0141] Preparation of mixed standards: Take 9840 μL of n-butanol (HPLC grade), put it into a 15 mL centrifuge tube, add appropriate amounts of 8 short-chain fatty acid standards, vortex and mix well to obtain mixed standard stock solution A of 8 short-chain fatty acids. Preparation of internal standard: Take 9990 μL of n-butanol (HPLC grade), put it into a 15 mL centrifuge tube, add 10 μL of internal standard 2-ethylbutyric acid, vortex and mix well to obtain internal standard stock solution B. Take the above mixed standard A and B solutions and dilute them with n-butanol to prepare 7 working solutions of different concentrations, put them into sample vials and perform GC-MS detection and analysis. Sample processing: Weigh 20 mg of cecal contents sample into a 2 mL grinding tube, add 800 μL of 0.5% phosphoric acid water (containing 10 μg / mL of internal standard 2-ethylbutyric acid). The sample was cryogenically ground for 3 min (50 Hz), then sonicated for 10 min, and centrifuged at 13000g for 15 min at 4 ℃. 200 μL of the supernatant was transferred to a 1.5 mL centrifuge tube, and then extracted with 200 μL of n-butanol. The mixture was vortexed for 10 s, sonicated at low temperature for 10 min, and centrifuged at 13000g for 5 min at 4 ℃. The supernatant was then transferred to a vial for GC-MS analysis. GC-MS detection: The analytical instrument used in this experiment was an Agilent Technologies Inc. (CA, UAS) 8890B-7000D GC / MSD system. Chromatographic conditions: HP FFAP capillary column (30 m × 0.25 mm × 0.25 μm, Agilent J&W Scientific, Folsom, CA, USA), carrier gas was high-purity helium (purity not less than 99.999%), flow rate was 1.0 mL / min, and the injection port temperature was 180 ℃. The injection volume was 1 μL, injected via split at a split ratio of 10:1, with a solvent delay of 2.5 min. Temperature programming: the initial temperature of the column oven was 80℃, increased to 120℃ at a rate of 20℃ / min, then to 160℃ at a rate of 5℃ / min, followed by a hold at 220℃ for 3 min. Mass spectrometry conditions: Electron impact ionization (EI) source, ion source temperature 230℃, quadrupole temperature 150℃, transfer line temperature 230℃, electron energy 70 eV. Selected ion scan mode (SIM) was used. Data analysis: Masshunter quantitative software (Agilent Technologies, v10.0.707.0) with default parameters was used for automatic identification and integration of ion fragments of the target short-chain fatty acids, supplemented by manual verification. The detection concentration of each sample was calculated using a standard curve to determine the actual content of short-chain fatty acids in the sample.

[0142] Test results

[0143] 1. YG2013 strain for preventing obesity caused by a high-fat diet

[0144] In this embodiment, the specific experimental methods were designed for animal experiments. The results of the YG2013 strain reducing weight gain and fat accumulation in HFD mice are shown in the appendix. Figure 7 .

[0145] like Figure 7 As shown in the results in AD, compared with ND-fed mice, HFD significantly increased body weight, epididymal weight, abdominal wall adipose tissue weight, and liver weight. After 8 weeks of YG2013 and Orlistat intervention, the HFD-induced increase in body and liver weight was effectively inhibited, and it helped to significantly reduce the epididymal and abdominal wall adipose tissue weight in HFD mice (see Appendix). Figure 7 (C and D). Among them, the YGMCC 2013 mice consistently had a lower body weight than the ND group from the first to the fifth week of intervention (see attached). Figure 7 (A)

[0146] 2. The YG2013 strain promotes beige transformation of white fatty tissue and reduces inflammation.

[0147] In this embodiment, the specific experimental methods were designed for animal experiments. The results of the YG2013 strain in alleviating inflammation and inducing beige remodeling of epididymal adipose tissue (eWAT) are shown in the appendix. Figure 8 .

[0148] As attached Figure 8 The results showed that strain YG2013 promoted beige cell development in eWAT and significantly reduced the size of adipocytes in the abdominal wall tissue of HFD mice (see Appendix). Figure 8 Mice in group B, compared to mice fed a normal diet, produced adipocyte morphology similar to that of mice in group B (see appendix). Figure 8 (A). Early studies have shown that bile acid G protein-coupled receptor 5 ( tgr5 Activation of ) increases energy expenditure and reduces fat mass, thus contributing to weight loss. tgr5 It is expressed in both white and brown adipose tissue, and bile acid activation of it increases energy expenditure and reduces diet-induced obesity. Il-27-Il-27Rα Signaling plays a crucial role in improving thermogenesis, preventing diet-induced obesity, and improving insulin resistance. Mechanistic studies have shown that... Il-27 It directly targets adipocytes, activates p38 MAPK–PGC-1α signaling, and stimulates the production of ucp1. Il-27 It plays a crucial role in coordinating metabolic processes and is a very promising target for anti-obesity immunotherapy. (See attached image) Figure 8 As shown in Figure D, this invention has found that in the epididymal adipose tissue of mice treated with YG2013,tgr5 , dio2 and Il-27 , Il-27Rα mRNA expression was significantly upregulated. To confirm the thermogenesis mechanism related to energy expenditure from YG2013 treatment, this study examined several markers associated with browning of white adipocytes in abdominal wall tissue. In epididymal tissue treated with YG2013 strain... ucp1 , pgc1α , prdm16 and pparα The significant upregulation of the gene indicates that YG2013 can regulate... Il-27 and tgr5 This process remodeled white adipocytes into beige ones. Compared to ND, HFD-fed mice showed no significant inflammatory response in their epididymal adipose tissue, while intervention with the YG2013 strain significantly increased anti-inflammatory factors. foxp3 The content (see appendix) Figure 8 (C)

[0149] 3. The YG2013 strain reduces inflammation and promotes thermogenic activity in BAT (baby-induced inflammatory response).

[0150] In this embodiment, the specific experimental methods were designed for animal experiments. The results of the YG2013 strain in reducing inflammation and activating brown adipose tissue thermogenic activity are shown in the appendix. Figure 9 .

[0151] As attached Figure 9 As shown in Figure AB, H&E staining indicated that YG2013 supplementation could reverse the enhanced BAT whitening process and the enlargement of intracellular lipid vesicles induced by HFD. This example found that YG2013 significantly upregulated [the process] in brown adipose tissue of mice treated with this strain. Il-27 and Il-27Rα mRNA expression was investigated. To confirm the thermic mechanism related to energy expenditure from the YG2013 treatment, several biomarkers associated with the thermic activity of brown adipose tissue were further examined. (See attached image) Figure 9 As shown in Figure D, treatment with strain YG2013 significantly upregulated the thermogenic gene in brown adipose tissue. ucp1 and pparα, elovl3 The expression of [something] indicates that strain YG2013 can regulate [something]. Il-27-Il-27Rα This amplifies the thermogenic metabolic effects of activating brown adipocytes in mice.

[0152] Brown adipose tissue contains a high concentration of mitochondria and releases large amounts of uncoupling protein 1 (UCP1) from the inner mitochondrial membrane. This uncoupling of mitochondrial respiratory chain oxidation and ADP phosphorylation transforms the process into a thermogenic one, leading to increased energy expenditure and heat production, thus achieving fat consumption and resulting in weight loss. HFD-fed mice also exhibited enhanced inflammatory responses and significantly increased inflammatory genes in their brown adipose tissue. Il-β, tnf-α , Il-6 and Il-8 expression, while YG2013 strain intervention significantly reduced the expression of inflammatory genes Il-4 and foxp3 (see Fig. C in the Appendix). Figure 9

[0153] 4. YG2013 strain improved liver steatosis and inflammation

[0154] In this example, the specific experimental methods are described in the Animal Experimental Design. The results of YG2013 strain reducing liver inflammation and improving liver steatosis are shown in Fig. A and C in the Appendix. Figure 10

[0155] As can be seen, YG2013 strain can significantly reduce HFD-induced liver lipid accumulation and hepatocyte swelling and inflammatory infiltration (see Fig. A and C in the Appendix). Moreover, YG2013 strain can significantly reduce HFD-induced liver lipid accumulation (see Fig. B in the Appendix). Compared with the ND group, HFD-fed mice also produced enhanced inflammatory response in liver tissue, increasing the expression of inflammatory genes Figure 10 and Figure 10 . While YG2013 strain intervention significantly reduced the expression of inflammatory genes Il-β , tnf-α (see Fig. D in the Appendix). Il-β, Il-6 tnf-α Figure 10 5. YG2013 intervention increased the concentration of SCFAs in HFD-fed mice

[0156] In this example, the specific experimental methods are described in the Animal Experimental Design. The results of YG2013 strain intervention increasing the concentration of SCFAs in HFD-fed mice are shown in Fig. in the Appendix.

[0157] As shown in Fig. in the Appendix, compared with fresh culture medium, the content of acetate and lactate in YG2013 culture medium increased, but the propionate and butyrate levels were similar between the culture medium and fresh culture medium (see the results of Example 3). Since cross-feeding, such as the use of acetate by butyrate-producing bacteria, is an important metabolic interaction between intestinal bacteria. This example further determined the concentration of various SCFAs in the cecal contents of mice by GC-MS analysis. As shown in Fig. A in the Appendix, acetate, propionate and butyrate are the main SCFAs in the cecal contents. Compared with the ND group, HFD feeding significantly reduced the levels of acetate, propionate, butyrate and total SCFAs in mice (see Fig. B in the Appendix). Figure 11

[0158] As shown in Fig. in the Appendix, compared with fresh culture medium, the content of acetate and lactate in YG2013 culture medium increased, but the propionate and butyrate levels were similar between the culture medium and fresh culture medium (see the results of Example 3). Since cross-feeding, such as the use of acetate by butyrate-producing bacteria, is an important metabolic interaction between intestinal bacteria. This example further determined the concentration of various SCFAs in the cecal contents of mice by GC-MS analysis. As shown in Fig. A in the Appendix, acetate, propionate and butyrate are the main SCFAs in the cecal contents. Compared with the ND group, HFD feeding significantly reduced the levels of acetate, propionate, butyrate and total SCFAs in mice (see Fig. B in the Appendix). Figure 11 Figure 11 Figure 11 ​​​​​​​​

[0159] In addition, YG2013 intervention significantly increased the levels of acetate (p<0.01), propionate (p<0.01), butyrate (p<0.001), isocaproate (p<0.01), isobutyrate (p<0.05), and valerate (p<0.0001) in the cecum of obese mice. These results collectively indicate that the YG2013 strain screened by the present application does not produce propionate and butyrate, but can provide acetate and lactate substrates to other intestinal symbiotic bacteria, thereby leading to an increase in the levels of propionate and butyrate in feces.

[0160] 6. YG2013 reshapes the intestinal microbiota of obese mice

[0161] In the present study, we investigated the effects of YG2013 on the diversity and composition of the intestinal microbiota of obese mice. For the analysis of microbial diversity, the present embodiment used 16S rRNA gene sequences.

[0162] As shown in Figure 12 The results of YG2013 changing the diversity and composition of the intestinal microbiota of HFD-fed mice; wherein A-B are Chao and Shannon, respectively, α-diversity analysis indicators; C is the PCoA plot analysis result of each sample; D is the Venn diagram result, showing the observed ASV overlap; E is the phylum level in the feces of mice; F is the bacterial community result at the family level.

[0163] As shown in Figure 12 The results show that the α-diversity of the high-fat diet group and the orlistat treatment group is significantly reduced, measured by the Shannon index and the Simpson index. However, the use of YG2013 treatment can reduce this decrease and maintain the diversity and richness of the intestinal microbiota. To further explore the differences in microbial structure, we performed principal coordinate analysis (PCoA) according to the unweighted UniFrac distance. The four groups all showed different microbial community compositions, but the YG2013 treatment group was more clustered with the ND group. This indicates that the supplementation of YG2013 can restore the composition of the intestinal microbiota to a level closer to that of mice on a normal diet. Analysis of operational taxonomic units (OTUs) showed that the number of unique OTUs in the YG2013 intervention group was significantly higher compared with the ND group and the orlistat treatment group. In addition, the YG2013 intervention group shared the most common OTUs (628) with the ND group. This indicates that YG2013 treatment retains the presence of specific microbial groups in mice on a normal diet. Further classification abundance analysis showed that the relative abundance of Firmicutes, Verrucomicrobia and Actinobacteria was higher in the HFD group compared with the ND group, while Bacteroidota was lower. However, compared with the HFD group, after the supplementation of YG2013, Verrucomicrobiaand Actinobacteria decreased, while Firmicutes and Bacteroidota increased. These changes indicated that YG2013 affected the relative abundance of different phyla in the gut microbiota of obese mice. At the family level, community abundance analysis showed that the YG2013 group had higher abundance of Muribaculaceae, Lachnospiraceae, Lactobacillaceae and Oscillospiraceae , while Akkermansiaceae, Clostridiaceae and unclassified_o_Vampirovibrionales were lower. These differences indicated that YG2013 treatment affected the composition of the gut microbiota at the family level. In summary, our study showed that the intervention of YG2013 improved the composition and diversity of the gut microbiota of obese mice. These research results indicated that YG2013 could be a potential therapeutic option for controlling the gut microbiota dysbiosis associated with obesity.

[0164] In this study, the composition of the gut microbiota of experimental mice was further analyzed, focusing on the abundance of 30 specific bacterial genera. As shown in Figure 13 , the results of the effect of YG2013 on the composition of intestinal bacteria; where A is the results of the genus-level heat map analysis; B is the LEfSe analysis (LDA>3); C-D are the Kruskal-Wallis H test bar chart at the genus level and the test chart at the species level (*p<0.05, **p<0.01, ***p<0.001).

[0165] As shown in the results in Figure 13 , compared with the ND group, the HFD group of mice had higher abundance of certain bacteria, including Allobaculum, Ileibacterium, Bifidobacterium, Akkermansia, Vampirovibrio, Clostridium, Dubosiella and Prevotella . Conversely, the HFD group had less Lactobacillus, Alistipes, Ruminococcus, Bacteroides, Limosilactobacillus, unclassified_f_Prevotellaceae and Lawsonibacter . To further study the effect of YG2013 treatment on the gut microbiota of high-fat diet-fed mice, we performed LEfSe analysis (see Figure 13 B). We found different bacteria associated with each group. Among them, the dominant genera of the ND, HFD and YG2013 groups were Muribaculum, Akkermansia and Allobaculum , respectively. Compared with the HFD group, YG2013 treatment led to a decrease in the abundance of Akkermansia, Ileibacterium, Vampirovibrio and Clostridium , while unclassified_f_Lachnospiraceae, Duncaniella, Lactobacillus and Eubacterium increased. In addition, we also analyzed the changes in the abundance of specific bacterial species using Kruskal-Wallis report (see Figure 13 C-D). Taking YG2013 led to an increase in beneficial bacteria, such as Limosilactobacillus reuteri,Bifidobacterium animalis and Duncaniella freteri . Also, it reduced the number of harmful bacteria such as Faecalibaculum rodentium, Ileibacterium valens, Romboutsia ilealis, unclassified_g_Clostridium These findings suggest that the composition of the gut microbiota of mice fed with a high-fat diet was altered, and the changes induced by YG2013 were beneficial. YG2013 treatment promoted the growth of beneficial bacteria and reduced the number of harmful bacteria, suggesting that it could be a therapeutic intervention to modulate the gut microbiota in obesity-related diseases.

[0166] Considering that YG2013 could improve obesity and gut microbiota dysbiosis in HFD-induced obese mice, we performed spearman correlation analysis to explore the associations between the dominant bacterial genera in the gut and metabolites (SCFAs) and obesity-related parameters (see Figure 14 A-B in the Methods section). Lactobacillus, Limosilactobacillus, Parabacteroides, unclassified_o_Eubacteriales and unclassified_f_Prevotellaceae strong positive correlation with the levels of at least four SCFAs. These genera also showed strong negative correlations with three obesity-related parameters. This suggests that these gut bacterial genera could play a role in SCFA production and the modulation of obesity-related parameters. On the other hand, Vampirovibrio, Romboutsia, Akkermansia, Prevotella and Clostridium showed significant negative correlations with the four SCFA indices. In addition, these genera also showed strong positive correlations with four obesity-related parameters. This suggests that these gut bacterial genera could be associated with reduced SCFA production and increased obesity-related indicators. Based on these findings, we investigated specific gut microbes related to the beneficial effects of YG2013 intervention on eWAT browning and BAT energy metabolism-related gene expression. We found that Lactobacillus, Bacteroides, Ruminococcus, Alistipes and Parabacteroides, showed positive correlations with eWAT browning but negative correlations with BAT energy metabolism and inflammatory factors such as Il-β , tnf-α , Il-6 and Il-8 On the other hand, Vampirovibrio, Ileibacterium and Faecalibacterium showed the opposite pattern. Notably, Allobaculum, Eubacterium, Dubosiella, Bifidobacterium and Romboutsia showed positive correlations with both eWAT browning and BAT energy metabolism. These findings demonstrate the complex interactions between gut bacteria in mice, SCFAs, obesity-related parameters, and metabolic processes. Understanding these interactions can provide valuable insights into the mechanisms of obesity and related diseases. Further research is needed to fully elucidate these mechanisms and explore potential therapeutic interventions targeting the gut microbiota and treating obesity and related diseases.

[0167] To gain a deeper understanding of the impact of YG2013 on gut bacterial function, we performed a KEGG pathway analysis to predict the functional pathways involved. Figure 14 The study analyzed the correlation between gut microbiota and obesity-related indices, as well as the pathways between different groups. Specifically, A represents the correlation between gut microbiota and biochemical indicators; B represents the correlation between gut microbiota and eWAT and BAT gene expression; and C represents the prediction of pathways with different abundances among groups based on KEGG pathway analysis.

[0168] like Figure 14 As shown in Figure C, all the aforementioned signaling pathways were significantly inhibited in the HFD group compared to the ND group. Similar effects were observed in the groups treated with orlistat, a drug known for its weight-loss effects. However, the groups treated with YG2013 completely reversed these signaling pathways, exhibiting effects similar to the ND group. More specifically, YG2013 significantly affected various metabolic pathways, increasing their activity. These pathways included energy metabolism pathways such as glycolysis I, II, and III, the pentose phosphate pathway – non-oxidative branch, and glycogen degradation I. YG2013 also affected carbohydrate metabolism pathways such as starch degradation V, pyruvate fermentation to acetic acid and lactate II, pyruvate fermentation to isobutanol, and isolate fermentation. These findings suggest that YG2013 may influence energy metabolism and the production of metabolites such as SCFAs by modulating the gut microbiota. This modulation of gut bacterial function may contribute to improving obesity in mice fed a high-fat diet. In conclusion, this analysis provides valuable insights into the potential mechanisms underlying the beneficial effects of YG2013 on gut bacteria and metabolism. It provides a promising avenue for further research and potential interventions for obesity-related diseases.

[0169] In summary, the Bifidobacterium lactis YG2013 described in this invention can be targeted and regulated. tgr5 / Il-27 This approach promotes the beige transformation of white adipose tissue and reduces its inflammatory effects, while also activating thermogenesis in brown adipose tissue and reducing its inflammatory effects. It can also alleviate hepatocyte steatosis and inflammatory responses, and produce various short-chain fatty acids to regulate energy metabolism. The strain can target and improve the characteristic gut microbiota of obesity, increasing the abundance of beneficial bacteria, reducing the abundance of harmful bacteria, and restoring the health of the gut microbiota, thus possessing significant application value.

[0170] Example 9

[0171] The Bifidobacterium lactis YG2013 described in this embodiment can be used to prepare probiotic preparations in various dosage forms, such as powders, granules, solid beverages, and compressed candies.

[0172] The Bifidobacterium lactis YG2013 described in the present embodiment can be added with conventional adjuvants or other active ingredients in the art, such as galacto-oligosaccharides, inulin, dietary fibers, and other beneficial ingredients, and can also be added with functional sugar alcohols for flavoring, fruit powders, and other ingredients, or functional ingredients such as malt dextrin.

[0173] In the probiotic preparation containing the Bifidobacterium lactis YG2013 as the active ingredient described in the present embodiment, the number of viable probiotic bacteria is controlled to be greater than 5 x 10 9 CFU / day / person.

[0174] The preparation method of the probiotic preparation containing the Bifidobacterium lactis YG2013 as the active ingredient described in the present embodiment can be processed using conventional processes in the art.

[0175] Obviously, the above embodiments are merely examples for the purpose of clear illustration, and are not intended to limit the embodiments. Based on the above description, other different forms of changes or variations can also be made by those of ordinary skill in the art. It is not necessary or possible to exhaust all the embodiments. The obvious changes or variations derived therefrom are still within the protection scope of the present application.

Claims

1. A strain of Bifidobacterium lactis ( Bifidobacterium lactis YG2013, characterized in that, It has been deposited at the China General Microbiological Culture Collection Center (CGMCC) with accession number CGMCC No. 27579 and deposit date of June 7, 2023.

2. The use of the Bifidobacterium lactis YG2013 according to claim 1 in the preparation of probiotic preparations.

3. A probiotic preparation, characterized in that, The active ingredient of the probiotic preparation includes the cells of Bifidobacterium lactis YG2013 as described in claim 1.

4. The probiotic preparation according to claim 3, characterized in that, The probiotic preparation is selected from at least one of the following: powder, granules, pills, capsules, tablets, ointments, liquid preparations, gels, or sprays.

5. A method for preparing the probiotic preparation according to any one of claims 3-4, characterized in that, It includes the step of culturing the Bifidobacterium lactis YG2013 as described in claim 1, and the step of processing the selected dosage form according to conventional processes and adding conventional excipients.

6. The use of the Bifidobacterium lactis YG2013 of claim 1 or the probiotic preparation of any one of claims 3-4 for the preparation of a functional medicament having at least one of the following effects (1)-(3): (1) Prevention and treatment of obesity; (2) It has a weight loss effect; (3) Relieves hepatocyte steatosis.

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