Application of a strain of Lactobacillus rhamnosus

Abstract

This invention belongs to the field of microbial technology, and specifically relates to the application of a strain of *Lactobacillus rhamnosus*. This invention discovers *Lactobacillus rhamnosus* 203-10, preservation number GDMCC No. 61778. In addition to possessing the conventional acid resistance, bile salt resistance, and immune-enhancing effects of *Lactobacillus rhamnosus*, this strain also effectively lowers uric acid, protects against kidney damage, lowers blood sugar, has strong antioxidant properties, regulates intestinal flora to restore intestinal health, and increases short-chain fatty acid levels. It is a multifunctional *Lactobacillus rhamnosus* strain with promising health applications and industrialization potential.

Description

Technical Field

[0001] This invention belongs to the field of microbial technology, and in particular, this invention relates to the application of a strain of Lactobacillus rhamnosus. Background Technology

[0002] Lactobacillus rhamnosus is one of the most thoroughly studied probiotics. It is a Gram-positive bacterium, morphologically short rod-shaped, non-spore-forming, facultative anaerobic, and exhibits good acid and bile salt tolerance and intestinal adhesion and colonization capabilities. Some health benefits of Lactobacillus rhamnosus include regulating gut microbiota to promote intestinal health, immune modulation, and anti-allergy effects.

[0003] Hyperuricemia and diabetes mellitus are two chronic metabolic diseases with a continuously rising global incidence. Hyperuricemia is characterized by abnormally high levels of uric acid in the blood, while diabetes mellitus is characterized by hyperglycemia due to insufficient insulin secretion or impaired insulin action. In recent years, numerous epidemiological and clinical studies have revealed a close and complex bidirectional link between these two diseases, which together constitute a core component of metabolic syndrome and significantly increase the risk of complications such as cardiovascular disease, kidney disease, and gout.

[0004] The interaction mechanism between hyperuricemia and hyperglycemia mainly manifests in two aspects. On the one hand, hyperuricemia is an independent risk factor for the development of type 2 diabetes. Elevated uric acid interferes with the insulin signaling pathway through pathways such as inducing oxidative stress and activating inflammasomes, leading to insulin resistance in peripheral tissues. Uric acid can also directly damage pancreatic β-cell function, reducing insulin secretion and thus causing hyperglycemia. On the other hand, blood glucose status also profoundly affects uric acid metabolism. In the early stages of the disease or the insulin resistance phase, the accompanying hyperinsulinemia can inhibit renal excretion of uric acid, leading to elevated serum uric acid levels. This dynamic and complex relationship means that the two diseases often coexist clinically and promote each other, posing a significant challenge to treatment.

[0005] Currently, clinical treatment for hyperuricemia mainly relies on xanthine oxidase inhibitors such as allopurinol and febuxostat to reduce uric acid production, or drugs such as benzbromarone to promote uric acid excretion. For diabetes, oral hypoglycemic agents (such as metformin and sulfonylureas) or insulin are used to control blood sugar. However, existing chemical drugs often have single targets, making it difficult to simultaneously intervene in two disease states, and long-term use may be accompanied by various side effects such as liver and kidney damage, gastrointestinal reactions, and allergies. Probiotic therapy, as an emerging microecological intervention strategy, has attracted widespread attention due to its high safety, few side effects, and potential to regulate host metabolism through multiple targets. CN201910336556.0 discloses a Lactobacillus rhamnosus that can lower blood uric acid levels, and can simultaneously degrade and utilize guanosine and its degradation product guanine, thus inhibiting both exogenous uric acid intake and endogenous uric acid elevation. CN202010699218.6 discloses a strain of Lactobacillus rhamnosus whose unactivated and inactivated fermentation supernatant (extracellular secretions), bacterial suspension (bacterial cells), and cell fragment supernatant (intracytoplasmic material) can significantly inhibit the activity of xanthine oxidase in zebrafish with high uric acid and significantly reduce the uric acid content in zebrafish with high uric acid.

[0006] Oxidative stress and chronic inflammation are important triggers for various metabolic diseases. Furthermore, the development of metabolic diseases leads to excessive production of inducible reactive oxygen species (ROS) in the body, activating inflammatory signaling pathways and creating a vicious cycle that exacerbates tissue damage and metabolic disorders. In addition, gut microbiota metabolites, such as short-chain fatty acids, have multiple physiological functions, including maintaining intestinal barrier integrity, inhibiting inflammatory responses, regulating energy metabolism, and improving insulin sensitivity. High uric acid and high blood sugar also affect gut microbiota composition and metabolic changes. While there are some reports of *Lactobacillus rhamnosus* simply lowering blood sugar, as the "Scientific Consensus on Probiotics (2020 Edition)" points out, different probiotic species have significant genomic differences, and even different strains of the same probiotic species exhibit variations. Because different strains of the same probiotic species contain or express different functional genes, they can exert different probiotic effects. Therefore, probiotics need to be characterized and described at the microbial strain level. *Lactobacillus rhamnosus*, with its more diverse functional characteristics, also requires further exploration. Summary of the Invention

[0007] In order to explore solutions to health problems such as high uric acid and high blood sugar, this invention has been developed through long-term research and testing. It has been found that Lactobacillus rhamnosus 203-10 has multiple functions such as lowering uric acid, lowering blood sugar, and anti-oxidation. This invention was thus completed.

[0008] In this invention, the Lactobacillus rhamnosus 203-10 is disclosed in the prior art CN202410047053.2, with accession number GDMCCNo.61778, accession date July 5, 2021, and accession address Guangdong Provincial Microbial Culture Collection Center, located at 5th Floor, Building 59, No. 100 Xianlie Middle Road, Guangzhou, Guangdong Institute of Microbiology.

[0009] In one aspect, the present invention discloses the application of Lactobacillus rhamnosus 203-10 in the preparation of products, said products having one or more of the following functions: (1) Reduce the body's uric acid content; (2) Lowering blood glucose levels or helping to maintain blood glucose balance in the body; (3) Antioxidant; (4) Regulate the gut microbiota, restore gut health, and increase the level of short-chain fatty acids in the gut.

[0010] In some embodiments, the present invention discloses the application of Lactobacillus rhamnosus 203-10 in the preparation of uric acid-lowering products.

[0011] In some embodiments, the present invention discloses the use of Lactobacillus rhamnosus 203-10 in the preparation of hypoglycemic or adjunctive hypoglycemic products.

[0012] In some embodiments, the present invention discloses the use of Lactobacillus rhamnosus 203-10 in the preparation of antioxidant products.

[0013] In some embodiments, the present invention discloses the application of Lactobacillus rhamnosus 203-10 in the preparation of a product that regulates intestinal flora and increases the level of short-chain fatty acids in the intestine.

[0014] In some embodiments, the product further includes one or more of the following: probiotics, prebiotics, dietary fiber, protein, polypeptides, amino acids, lipids, carbohydrates, vitamins, minerals, and plant extracts.

[0015] As used herein, the term “probiotic” is defined as any non-pathogenic microorganism that, when administered to a host in sufficient quantities in live form, can have a beneficial effect on the host’s health.

[0016] In some embodiments, the probiotics are strains listed in the list of bacteria that can be used in food. Preferably, the probiotics are selected from one or a combination of Bifidobacterium, Lactobacillus, Lactobacillus casei, Lactobacillus fermentum, Lactobacillus reuteri, Lactobacillus plantarum, Lactobacillus salivarius, Streptococcus thermophilus subsp. saliva, Lactococcus lactis subsp. lactis, Lactococcus fat, Propionibacterium propionate, Leuconostoc mesenteroides subsp. mesenteroides, Pediococcus lactis, Weizmann's coagulans, and Kluyveromyces martensii.

[0017] In some embodiments, the prebiotic is selected from fructooligosaccharides, galactooligosaccharides, inulin, lactulose, isomaltooligosaccharides, polydextrose, human milk oligosaccharides (HMOs), xylooligosaccharides, resistant starch, soybean oligosaccharides, and stachyose.

[0018] In some embodiments, the carbohydrate is selected from monosaccharides (glucose, fructose, xylose), disaccharides (sucrose, maltose, lactose), polysaccharides, sugar alcohols (xylitol, sorbitol, mannitol, erythritol) or any combination thereof.

[0019] In some embodiments, the product is selected from food, health food, dietary supplements, and pharmaceuticals.

[0020] In this invention, the term "food" has a broad meaning, including food or beverages for humans or animals. The food is selected from solid beverages, confectionery, liquid beverages, biscuits or dairy products, freeze-dried powders, chocolate, and ice cream. In animals, the food is provided in the form of animal feed.

[0021] In this invention, the dietary supplement refers to an edible product that can increase the nutritional value or health benefits for consumers, and is used to supplement the dietary nutrients such as amino acids, vitamins, and minerals required by the human body.

[0022] In this invention, the term "medicine" refers to a product intended for the prevention or treatment of disease. The medicine is applicable to both humans and animals. Animals, especially those closely related to human production and daily life, include poultry, livestock, and pets.

[0023] In some embodiments, the product can be processed into various dosage forms. Common dosage forms for pharmaceuticals include powders, gels, oral liquids, capsules, and tablets; common dosage forms for health foods and dietary supplements include hard capsules, soft capsules, tablets, powders, oral liquid preparations, gel candies, pills, and drops.

[0024] In some embodiments, the health food, dietary supplement, and pharmaceutical product also contain additives / excipients acceptable to food, health food, and pharmaceutical product.

[0025] In some embodiments, the excipients include fillers (diluents), binders, lubricants, flow aids, thickeners, flavoring agents, disintegrants, edible oils, stabilizers, suspending agents, surfactants, or any combination thereof. The specific selection and combination of excipients can be made by those skilled in the art based on the product's dosage form, usage requirements, and desired effects.

[0026] In some embodiments, the filler is selected from soluble starch, resistant dextrin, starch, corn starch, and microcrystalline cellulose; the binder is selected from hydroxymethyl cellulose, povidone, dextrin, syrup, sugar alcohol, hydroxymethyl cellulose, hydroxypropyl cellulose, and methyl cellulose; the disintegrant is selected from crospovidone, crospovidone, and polyvinylpyrrolidone; and the lubricant is selected from stearic acid, magnesium stearate, polyethylene glycol, and hydrogenated vegetable oil.

[0027] In some embodiments, the additive is selected from sweeteners, flavoring agents, colorings, antioxidants, preservatives, edible flavorings, edible spices, enzyme preparations, and moisture retainers.

[0028] In some embodiments, the compositions / products of the present invention include one or more of the following: live Lactobacillus rhamnosus 203-10, dried Lactobacillus rhamnosus 203-10, strain metabolites, and inactivated strains (post-biotics).

[0029] In some embodiments, the composition / product of the present invention contains more than 10 probiotics, including Lactobacillus rhamnosus 203-10. 6 CFU / g or greater than 10 6 CFU / mL.

[0030] In some embodiments, the compositions, ferments, and products of the present invention contain more than 10 *Lactobacillus rhamnosus* 203-10. 6 The amount of CFU / dose present (e.g., 10) 7 CFU / dosage, 10 8 CFU / dosage, 10 9 CFU / dosage, 10 10 CFU / dosage, 10 11 CFU / dosage, 10 12 CFU / dosage). The unit of dosage can be g or mL.

[0031] As used in this article, the term "CFU (Colony-Forming Units)" refers to the total number of microbial communities such as bacteria, fungi, and yeast in a product, and is usually used to calculate the number of viable cells.

[0032] In this invention, Lactobacillus rhamnosus 203-10 has the following functions: (1) Reduce the body's uric acid content; (2) Lowering blood glucose levels or helping to maintain blood glucose balance in the body; (3) Antioxidant; (4) Regulate the gut microbiota, restore gut health, and increase the level of short-chain fatty acids in the gut.

[0033] Beneficial effects This invention discovers that *Lactobacillus rhamnosus* 203-10, in addition to possessing the conventional acid resistance, bile salt resistance, and immune-enhancing effects of *Lactobacillus rhamnosus*, also effectively lowers uric acid, protects against kidney damage, lowers blood sugar, has strong antioxidant properties, regulates intestinal flora to restore intestinal health, and increases short-chain fatty acid levels. It is a multifunctional *Lactobacillus rhamnosus* strain, laying the foundation for expanding its health applications and industrialization. Attached Figure Description

[0034] Figure 1 The protective effect of Lactobacillus rhamnosus 203-10 against kidney damage induced by hyperuricemia in rats.

[0035] Figure 2 Analysis of rat gut microbiota NMDS.

[0036] Figure 3 Analysis of LEfSe in rat gut microbiota. Detailed Implementation

[0037] The embodiments of the present invention will be described in detail below with reference to examples. However, those skilled in the art will understand that the following examples are for illustrative purposes only and should not be considered as limiting the scope of the invention. Unless otherwise specified, specific conditions in the examples are performed under conventional conditions or conditions recommended by the manufacturer. Reagents or instruments used without specified manufacturers are all commercially available conventional products. Unless otherwise specified, "room temperature" in the examples refers to 20-25°C.

[0038] Reagents and materials: Allopurinol was purchased from Sigma-Aldrich (USA); potassium oxonate and sodium xanthine were purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.; high-purine feed was purchased from Jiangsu Xietong Pharmaceutical Bioengineering Co., Ltd.; uric acid standard and xanthine oxidase activity assay kit were purchased from Beijing Solarbio Biotechnology Co., Ltd.; metformin hydrochloride tablets were purchased from Sino-American Shanghai Squibb Co., Ltd.; egg yolk powder and glucose were purchased from Shanghai Maclean Biochemical Technology Co., Ltd.

[0039] Strain source: Lactobacillus rhamnosus 203-10, which has been disclosed in prior invention CN202410047053.2, accession number GDMCCNo.61778, accession date July 5, 2021, accession address Guangdong Provincial Microbial Culture Collection Center, accession address is Guangdong Institute of Microbiology, 5th Floor, Building 59, No. 100 Xianlie Middle Road, Guangzhou.

[0040] Lactobacillus rhamnosus 207-18, Lactobacillus rhamnosus 232-41, and Lactobacillus rhamnosus 203-18 are from By-Health's proprietary strain library.

[0041] Example 1: Screening for uric acid-lowering Lactobacillus rhamnosus using zebrafish test 1.1 Test Method Wild-type AB strain zebrafish, 5 days post-fertilization (5 dpf), were randomly selected and placed in 6-well plates. Each well (experimental group) contained 30 zebrafish, and each well had a volume of 3 mL. A normal control group, a model control group, an allopurinol group (positive control), and a probiotic group were established. The normal control group was fed normally, while the other groups were given potassium oxonate and sodium xanthine in water to establish a zebrafish hyperuricemia model. The positive control group was given 1000 μM allopurinol in water, and the probiotic group was given 1×10⁻⁶ μM allopurinol in water. 7 CFU / mL probiotics were used, with strains all derived from *Lactobacillus rhamnosus* isolated from the Tomson Biotech strain library. After treatment at 28℃ for 1 day, data were collected using the AmplexRed Uric uric acid kit and multi-functional microplate reader software. The uric acid fluorescence value of the zebrafish was analyzed, and the statistical analysis results of this index were used to evaluate the uric acid-lowering efficacy of the samples.

[0042] 1.2 Test Results Table 1 shows that under the test conditions, the uric acid level in the model control group of zebrafish was significantly higher than that in the normal control group, indicating that the experimental model was successfully established. Compared with the model control group, intervention with *Lactobacillus rhamnosus* 203-10 significantly reduced the uric acid level in zebrafish, indicating that *Lactobacillus rhamnosus* 203-10 has a uric acid-lowering effect. However, the uric acid-lowering effects of *Lactobacillus rhamnosus* 207-18 and *Lactobacillus rhamnosus* 232-41 were not significant.

[0043] Table 1: Uric acid fluorescence values ​​of different groups

[0044] Note: Compared with the model control group, *P < 0.05, **P < 0.01, ***P < 0.001.

[0045] Example 2: Screening for hypoglycemic Lactobacillus rhamnosus using zebrafish test 2.1 Test Method Wild-type AB strain zebrafish, 5 days post-fertilization (5 dpf), were randomly selected and placed in beakers, with 30 zebrafish treated in each beaker (experimental group). Samples (concentrations shown in Table 2) were administered in water, along with a positive control of metformin at a concentration of 400 μg / mL. A normal control group and a model control group were also included. Each beaker contained 25 mL of glucose. Except for the normal control group, the other test groups were administered a 0.15% egg yolk powder solution during the day and a 3% glucose solution at night to establish a zebrafish hyperglycemia model. After treatment at 28℃ for 2 days, the zebrafish were washed three times with standard dilution water, and data were collected using a glucometer. The glucose levels of the zebrafish were analyzed and statistically analyzed to evaluate the hypoglycemic efficacy of the samples.

[0046] 2.2 Test Results Table 2 shows that under the test conditions, the blood glucose level of the zebrafish in the model control group was significantly higher than that in the normal control group, indicating that the hyperglycemia model was successfully established. Compared with the model control group, intervention with *Lactobacillus rhamnosus* 203-10 significantly reduced the glucose level of zebrafish, indicating that *Lactobacillus rhamnosus* 203-10 has a hypoglycemic effect. However, the hypoglycemic effects of *Lactobacillus rhamnosus* 207-18 and *Lactobacillus rhamnosus* 232-41 were not significant. Furthermore, although *Lactobacillus rhamnosus* 207-18 had a stronger uric acid-lowering ability than *Lactobacillus rhamnosus* 232-41, its hypoglycemic ability was weaker, reflecting the differences in different efficacy directions among different strains.

[0047] Table 2. Results of the experiment evaluating the hypoglycemic effect of zebrafish

[0048] Note: Compared with the model control group, *P < 0.05, **P < 0.01, ***P < 0.001.

[0049] Example 3: Screening of antioxidant Lactobacillus rhamnosus by zebrafish test 3.1 Test Method Wild-type AB strain zebrafish, 5 days post-fertilization (5 dpf), were randomly selected and placed in 6-well plates, with 30 zebrafish treated in each well (experimental group). A normal control group, a glutathione group (positive control), and a probiotic group were set up, with samples administered in water (concentrations shown in Table 3). The solutions were diluted to 3 mL per well with ROS fluorescence detection buffer. After treatment at 28℃ for 24 h, the zebrafish from each experimental group were transferred to black 96-well microplates, 2 zebrafish per well, with a volume of 100 µL per well. ROS fluorescence values ​​of the zebrafish in each experimental group were analyzed using a multi-functional microplate reader. The statistical analysis results of this index were used to evaluate the antioxidant efficacy of the samples.

[0050] 3.2 Test Results As shown in Table 3, under the test conditions, the ROS fluorescence values ​​of zebrafish in the glutathione group (positive control) and the Lactobacillus rhamnosus 203-10 group were significantly lower than those in the normal control group. The ROS value of Lactobacillus rhamnosus 203-10 was close to that of the glutathione positive group, indicating that Lactobacillus rhamnosus 203-10 has a very strong antioxidant effect.

[0051] Table 3. Results of antioxidant experiments in zebrafish

[0052] Note: Compared with the normal group, *P < 0.05, **P < 0.01, ***P < 0.001.

[0053] Example 4. Test for reducing uric acid in rats using Lactobacillus rhamnosus 203-10. 4.1 Test Animals Male SD rats aged 6–8 weeks (weighing 200–220 g) were housed in an environment meeting the specific pathogen-free (SPF) standard. The ambient temperature was 21±2℃, the humidity was 50±10%, and there was a 12-hour light-dark cycle. The rats had free access to water and food during the test period.

[0054] 4.2 Test Methods After one week of acclimatization, 32 rats were randomly divided into four groups: normal control group (Con group), hyperuricemia model group (HUA group), positive drug intervention group (AP group), and Lactobacillus rhamnosus 203-10 group (LR group). The Con group was fed a normal diet, while the other groups were fed a high-purine diet (containing 20% ​​yeast extract and 0.1% adenine) and administered 300 mg / kg potassium oxonate daily by gavage to establish a hyperuricemia model. One hour after administering potassium oxonate daily, the AP group was administered 20 mg / kg allopurinol by gavage, and the LR group was administered 1×10 mg / kg allopurinol by gavage. 8 Rats in the CFU-containing Lactobacillus rhamnosus 203-10 group (Con group and HUA group) were administered an equal volume of sterile saline by gavage. The test lasted for 4 weeks, and uric acid levels in tail vein blood were measured at weeks 0, 2, and 4. At the end of the test, serum, liver, kidney, and colon samples were collected for further analysis.

[0055] 4.3 Test Results (a) Blood uric acid level Table 4 shows that at the beginning of the experiment (week 0), the serum uric acid levels of rats in all groups were at the same level, with no significant differences between groups. From week 2 after modeling, the serum uric acid level in the HUA group was significantly higher than that in the Con group, and by week 4, the serum uric acid level had increased to 2.2 times that of the Con group, indicating that the hyperuricemia model was successfully established. The LR group rats began to exert a uric acid-lowering effect as early as week 2, and the serum uric acid levels in weeks 2 and 4 were significantly lower than those in the HUA model group, indicating that *Lactobacillus rhamnosus* 203-10 can significantly alleviate hyperuricemia.

[0056] Table 4. Changes in serum uric acid levels in rats (n = 8)

[0057] Note: Compared with the HUA group, *P < 0.05, **P < 0.01, ***P < 0.001.

[0058] (ii) Blood glucose level Hyperuricemia can induce insulin resistance and pancreatic β-cell dysfunction, thereby increasing the risk of type 2 diabetes. Table 5 shows that after four weeks of hyperuricemia modeling, the blood glucose level in rats was significantly higher than that in the Con group (P < 0.05), indicating that hyperuricemia increases the risk of hyperglycemia in rats. Compared with the HUA group, although the AP group showed a trend towards lowering blood glucose, the difference was not statistically significant, while the blood glucose level in the LR group was significantly lower (P < 0.001), indicating that *Lactobacillus rhamnosus* 203-10 can maintain blood glucose balance in rats with hyperuricemia and has a highly significant hypoglycemic effect, which is an unexpected result.

[0059] Table 5. Blood glucose levels in rats (n = 8)

[0060] Note: Compared with the HUA group, *P < 0.05, **P < 0.01, ***P < 0.001.

[0061] (III) Changes in liver function Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) are important indicators for assessing liver function. When liver cells are damaged, AST and ALT are released from the liver, causing elevated levels in the blood. Table 6 shows that serum ALT and AST levels in the HUA group were significantly higher than those in the Con group, indicating that hyperuricemia induced liver damage. Compared with the HUA group, serum ALT and AST levels in the LR group were significantly decreased, recovering to levels consistent with the Con group. These results indicate that *Lactobacillus rhamnosus* 203-10 can alleviate liver damage caused by hyperuricemia.

[0062] Table 6. Serum liver function indicators in rats (n = 8)

[0063] Note: Compared with the HUA group, *P < 0.05, **P < 0.01, ***P < 0.001.

[0064] (iv) Changes in renal function The kidneys are vital organs for uric acid excretion. Elevated blood uric acid levels lead to urate crystal deposition that obstructs renal tubules, activates inflammatory responses and oxidative stress, and damages vascular endothelium, resulting in renal dysfunction. At the end of the test, H&E-stained sections of kidney tissue from rats in each group were observed, and pathological scores were assigned based on uric acid deposition, inflammatory infiltration, and secondary structural damage. Figure 1 It was found that, compared with the Con group, the HUA group rats showed significant uric acid crystal deposition in their kidneys, with extensive inflammatory cell infiltration and cavitary necrosis in the interstitial region. In contrast, the LR group rats showed significantly improved uric acid crystal formation in their kidneys compared with the HUA group, and their pathological scores were significantly lower.

[0065] Creatinine (Cr) and blood urea nitrogen (BUN) are two important indicators for clinically assessing renal function. When the kidneys are damaged, the levels of serum creatinine and BUN will significantly increase. Table 7 shows that serum Cr and BUN levels in the HUA group were significantly higher than those in the Con group, indicating renal impairment. The AP group had no protective effect against renal damage, showing virtually no reduction in serum Cr and BUN levels. Compared with the HUA group, the LR group showed a significant decrease in Cr and BUN levels. These results indicate that *Lactobacillus rhamnosus* 203-10 can alleviate renal pathological damage caused by hyperuricemia.

[0066] Table 7. Serum renal function indicators in rats (n = 8)

[0067] Note: Compared with the HUA group, *P < 0.05, **P < 0.01, ***P < 0.001.

[0068] (iv) Inflammation status As shown in Table 8, compared with the HUA model group, the serum IL-6 and IL-1β levels in the LR group rats were significantly reduced, indicating that Lactobacillus rhamnosus 203-10 can significantly inhibit inflammation caused by hyperuricemia.

[0069] Table 8. Serum inflammatory factor levels in rats (n = 8)

[0070] Note: Compared with the HUA group, *P < 0.05, **P < 0.01, ***P < 0.001.

[0071] This embodiment demonstrates that Lactobacillus rhamnosus 203-10 has the effects of lowering blood uric acid and blood sugar in rats with hyperuricemia, and can significantly improve liver and kidney damage and systemic inflammation.

[0072] (v) Short-chain fatty acid levels Short-chain fatty acids (SCFAs) are key metabolites produced by the gut microbiota and are one of the core indicators reflecting the health level of the gut microbiota, playing an important role in regulating host physiological functions. SCFAs such as acetic acid, propionic acid, and butyric acid are not only the main energy source for colonic epithelial cells but also influence systemic metabolic homeostasis by regulating immune responses, maintaining intestinal barrier integrity, and affecting immune function. The concentration of SCFAs in the cecal contents was measured. As shown in Table 9, the levels of the three SCFAs in the cecum of rats with hyperuricemia were significantly reduced after the model was established. Compared with the HUA model group, the levels of acetic acid, propionic acid, and butyric acid in the cecum of the LR group rats were significantly increased, approaching normal levels, indicating that *Lactobacillus rhamnosus* 203-10 can increase the level of SCFAs and has the potential to regulate the gut microbiota.

[0073] Table 9. Short-chain fatty acid levels in rat cecal contents (n = 8)

[0074] Note: Compared with the HUA group, *P < 0.05, **P < 0.01, ***P < 0.001.

[0075] (vi) Changes in gut microbiota Gut microbiota dysbiosis is closely associated with hyperuricemia; therefore, 16S rRNA amplicon sequencing was used to further analyze the composition of the gut microbiota in the test mice. NMDS (Nonmetric Multidimensional Scaling) plots were used to visually reduce the dimensionality and observe the differences in bacterial community structure among the groups. Figure 2 It was found that the Con group and the HUA group were significantly separated, indicating that the hyperuricemia model led to significant changes in the gut microbiota structure. A certain degree of separation existed between the LR group and the HUA group, suggesting that *Lactobacillus rhamnosus* 203-10 can regulate the gut microbiota structure under hyperuricemia model conditions. Further LEfSe analysis (linear discriminant effect size analysis) was used to identify differences in bacterial taxa among the different groups. Figure 3 It can be seen that the LR group promoted g_ Prevotellaceae_Ga6A1_group , g_NK4A214_group and g_Lacticaseibacillus enrichment, Lacticaseibacillus It is a widely studied genus of probiotics, and g_Prevotellaceae_Ga6A1_groupand g_ NK4A214_group The correlation with the production of short-chain fatty acids indicates that intervention with Lactobacillus rhamnosus 203-10 effectively increased the abundance of beneficial gut bacteria and short-chain fatty acid-producing bacteria.

[0076] In summary, this invention has discovered that Lactobacillus rhamnosus 203-10 has multiple functions, including lowering uric acid, lowering blood sugar, anti-oxidation, increasing the level of short-chain fatty acids in the intestine, and regulating the intestinal flora to restore intestinal health. This lays the foundation for expanding the application scope and industrialization of this probiotic.

[0077] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. The application of *Lactobacillus rhamnosus*, wherein *Lactobacillus rhamnosus* is *Lactobacillus rhamnosus* 203-10, preservation number GDMCC No. 61778, characterized in that, Lactobacillus rhamnosus 203-10 is used to prepare a product, which has one or more of the following functions: (1) Reduce the body's uric acid content; (2) Lowering blood glucose levels or helping to maintain blood glucose balance in the body; (3) Antioxidant; (4) Regulate the gut microbiota, restore gut health, and increase the level of short-chain fatty acids in the gut.

2. The application according to claim 1, characterized in that, The product also contains one or more of the following: probiotics, prebiotics, dietary fiber, protein, polypeptides, amino acids, lipids, carbohydrates, vitamins, minerals, and plant extracts.

3. The application according to claim 2, characterized in that, The probiotics are selected from one or a combination of Bifidobacterium, Lactobacillus, Lactobacillus fermentum, Lactobacillus reuteri, Lactobacillus plantarum, Lactobacillus salivarius, Streptococcus thermophilus subsp. saliva, Lactococcus lactis subsp. lactis, Lactococcus fat-producing bacteria, Propionibacterium propionitum, Leuconostoc mesenteroides subsp. mesenteroides, Pediococcus lactis, Weizmann's coagulans, and Kluyveromyces maculae.

4. The application according to claim 2, characterized in that, The prebiotics are selected from fructooligosaccharides, galactooligosaccharides, inulin, lactulose, isomaltooligosaccharides, polydextrose, human milk oligosaccharides (HMOs), xylooligosaccharides, resistant starch, soybean oligosaccharides, and stachyose.

5. The application according to claim 2, characterized in that, The carbohydrates are selected from monosaccharides (glucose, fructose, xylose), disaccharides (sucrose, maltose, lactose), polysaccharides, sugar alcohols (xylitol, sorbitol, mannitol, erythritol) or any combination thereof.

6. The application according to claim 2, characterized in that, The products are selected from food, health food, dietary supplements, and pharmaceuticals.

7. The application according to claim 6, characterized in that, The food, health food, dietary supplement, and medicine mentioned also contain additives / excipients that are acceptable in food, health food, and medicine.

8. The application according to claim 2, characterized in that, The product includes one or more of the following: live Lactobacillus rhamnosus 203-10, dried Lactobacillus rhamnosus 203-10, strain metabolites, and inactivated strains (post-biotics).

9. The application according to claim 2, characterized in that, The dosage forms of the product are hard capsules, soft capsules, tablets, powders, oral liquid preparations, gel candies, pills, and drops.

10. The application according to claim 2, characterized in that, The product contains more than 10% Lactobacillus rhamnosus 203-10. 6 The amount of CFU / dose present.

Images