Preparation method of glucose fermentation product with bacteriostatic activity

Abstract

The invention relates to the technical field of microbial fermentation, in particular to a preparation method of a glucose fermentation product with bacteriostatic activity, which comprises the following steps: (1) inoculating a lactococcus lactis subsp. Lactis seed solution into a glucose-containing fermentation culture solution, and fermenting to obtain a first fermentation solution; (2) inoculating a pediococcus acidilactici seed solution into the first fermentation liquor, supplementing glucose, and fermenting to obtain second fermentation liquor; and (3) adjusting the pH value of the second fermentation liquor to be acidic, filtering, concentrating, and spray-drying to obtain the glucose fermentation product. According to the invention, the characteristic that organic acids and bacteriocin generated by lactococcus lactis subsp. Lactis and pediococcus acidilactici are different in types is fully utilized, metabolites of the two bacteria are obtained at the same time by adopting a sequential sequence type fermentation mode, and the metabolites of the lactococcus lactis subsp. Lactis are converted by pediococcus acidilactici, so that a new substance with bacteriostatic activity is obtained; the antibacterial activity is improved. Meanwhile, the problem of nutrition competition caused by mixed culture of the two bacteria is avoided, and the fermentation efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of microbial fermentation, and in particular to a method for preparing a glucose fermentation product with antibacterial activity. Background Art

[0002] Lactic acid bacteria are named after the lactic acid they produce. They are favored by researchers, producers and consumers for their high safety and good physiological functions, especially for regulating intestinal function and lowering cholesterol. They are also a frequent visitor to fermented foods, such as sauerkraut, mustard tuber, ham, etc. The substances such as lactic acid, acetic acid and bacteriocins produced by lactic acid bacteria play a more obvious role in preserving food and extending shelf life.

[0003] Lactococcus lactis subsp. lactis ( Lactococcus lactis subsp. Lactis ) is a common probiotic, an important subspecies of the genus Lactococcus. It has a spherical or oval cell morphology, and appears as a single, paired or chain arrangement under a microscope. This strain can ferment a variety of sugars and produce lactic acid and other organic acids, giving the product a unique flavor and taste.

[0004] Pediococcus acidilactici ( Pediococcus acidilactici ) belongs to the genus Pediococcus among lactic acid bacteria. This type of bacteria will produce organic acids such as lactic acid and acetic acid during the fermentation process. These organic acids not only have an important influence on the flavor and texture of food, but also have certain antibacterial activity and can be used for food preservation and anti-corrosion.

[0005] In the prior art, when Lactococcus lactis subsp. lactis and Pediococcus acidilactici are used alone, the types of organic acids produced by fermenting glucose are relatively single, and the bacteriocins produced are also very limited, so their antibacterial effects in food will be greatly reduced, and the shelf life of the food will be difficult to achieve expectations. Summary of the invention

[0006] In view of the technical problem that in the existing lactic acid bacteria fermentation glucose production, the fermentation product has a single type of organic acid, resulting in low antibacterial activity, the present invention provides a method for preparing a glucose fermentation product with antibacterial activity, which can improve the antibacterial activity of the glucose fermentation product and extend the shelf life of the product.

[0007] The present invention provides a method for preparing a glucose fermentation product having antibacterial activity, comprising the following steps: (1) inoculating a Lactococcus lactis subspecies lactis seed liquid into a fermentation culture liquid containing glucose to ferment to obtain a first fermentation liquid; (2) inoculating the first fermentation liquid with the seed liquid of Pediococcus acidilactici, adding glucose, and fermenting to obtain the second fermentation liquid; (3) The pH of the second fermentation liquid is adjusted to acidic, and the glucose fermentation product is obtained after filtering, concentrating, and spray drying.

[0008] Furthermore, in step (1), the method for preparing the Lactococcus lactis subsp. lactis seed solution comprises inoculating Lactococcus lactis subsp. lactis at an inoculation rate of 1% to 5% into an MRS liquid culture medium, culturing at a temperature of 28 to 32° C. for 16 to 20 hours, and obtaining an OD 600 The culture solution with an OD value of 2-4 was inoculated into the seed tank at an inoculation rate of 1%-5%, and cultured at 28-32℃ for 8-12h to obtain the OD 600 Seed solution with a value of 2~4.

[0009] Furthermore, in step (1), the fermentation broth comprises the following components in concentrations: 15-30 g / L glucose, 5-15 g / L yeast extract, 1-3 g / L potassium dihydrogen phosphate, 1-3 g / L magnesium sulfate heptahydrate, and 1-2 g / L Tween 80.

[0010] Further, in step (1), the fermentation conditions include: the inoculation amount of Lactococcus lactis subspecies Lactis is 8% to 15%, and the fermentation is carried out at a temperature of 28 to 32°C for 8 to 12 hours to obtain an OD 600 The first fermentation liquid has a value of 6~8 and a lactic acid content of 6~8g / L.

[0011] Furthermore, in step (2), the method for preparing the seed solution of Pediococcus acidilactici comprises inoculating Pediococcus acidilactici with an inoculum amount of 1% to 5% in MRS liquid culture medium, culturing at a temperature of 28 to 32° C. for 16 to 20 hours, and obtaining an OD 600 The culture solution with an OD600 value of 2~4 is added to the seed tank at an inoculation rate of 1%~5%, and cultured at 28~32℃ for 8~12h to obtain a seed solution with an OD600 value of 2~4.

[0012] Further, the MRS liquid culture medium used in the present invention comprises the following components in concentrations: peptone 5-15 g / L, beef extract powder 5-15 g / L, yeast powder 2-6 g / L, glucose 10-20 g / L, sodium acetate 1-5 g / L, diammonium citrate 1-5 g / L, Tween 80 1-2 g / L, dipotassium hydrogen phosphate 1-3 g / L, magnesium sulfate heptahydrate 1-3 g / L, and manganese sulfate 0.1-0.3 g / L.

[0013] Furthermore, in step (2), the inoculation amount of the lactic acid Pediococcus seed solution is 15% to 25%, glucose is added at 20 to 30 g / L, and fermented at a temperature of 28 to 32 ° C for 8 to 12 h to obtain an OD 600 The second fermentation broth has a value of 8~12 and a lactic acid content of 10~15g / L.

[0014] Furthermore, in step (3), hydrochloric acid is used to adjust the pH of the second fermentation liquid to 2-4.

[0015] Furthermore, in step (3), the second fermentation liquid after pH adjustment is filtered using a ceramic membrane, and the filtrate after filtration is concentrated 10 to 15 times to obtain a concentrated liquid.

[0016] Furthermore, 5% to 10% maltodextrin is added to the concentrate and then spray-dried.

[0017] The beneficial effects of the present invention are as follows: the present invention makes full use of the different characteristics of organic acids and bacteriocins produced by Lactococcus lactis subsp. lactis and Pediococcus acidilactici, adopts a sequential fermentation method, obtains metabolites of the two bacteria at the same time, and uses Pediococcus acidilactici to transform the metabolites of Lactococcus lactis subsp. lactis to obtain new substances with antibacterial activity, thereby improving the antibacterial activity. At the same time, the present invention avoids the nutritional competition problem caused by direct mixed bacterial culture of the two bacteria, thereby improving the fermentation efficiency. DETAILED DESCRIPTION

[0018] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0019] The Lactococcus lactis subsp. lactis strain numbered ATCC 11454 and the Pediococcus acidilactici strain numbered DSM 20284 used in the following examples of the present invention are both commercially available.

[0020] Example 1 (1) Preparation of seed solution Prepare MRS liquid culture medium in advance, with the formula containing 5 g of peptone, 5 g of beef extract powder, 2 g of yeast powder, 10 g of glucose, 1 g of sodium acetate, 1 g of diammonium citrate, 2 g of Tween 80, 1 g of dipotassium hydrogen phosphate, 1 g of magnesium sulfate heptahydrate, and 0.1 g of manganese sulfate per liter of culture medium.

[0021] Lactococcus lactis subsp. lactis seed liquid: Pick a single colony of Lactococcus lactis subsp. lactis after activation, inoculate it into liquid MRS medium at a rate of 3%, and culture it in a 30°C incubator for 18 h to obtain the OD 600 The culture solution with a value of 3 was inoculated into the seed tank at a rate of 3% and fermented at 30°C for 10 h to obtain the OD 600 The value is 3 for Lactococcus lactis subsp. lactis seed liquid.

[0022] Seed liquid of Pediococcus acidilactici: Pick a single colony of activated Pediococcus acidilactici and inoculate it into liquid MRS medium at a rate of 3%. Incubate it in a 30°C incubator for 18 h to obtain the OD600 The culture solution with an OD600 value of 3 was inoculated into the seed tank at a 3% inoculation rate and cultured at 30°C for 10 h to obtain a seed solution of Pediococcus acidilactici with an OD600 value of 3.

[0023] (2) Fermentation broth preparation The fermentation culture medium was prepared in advance, and its formula was 20 g / L glucose, 10 g / L yeast extract powder, 2 g / L potassium dihydrogen phosphate, 2 g / L magnesium sulfate heptahydrate, and 1 g / L Tween 80.

[0024] The prepared Lactococcus lactis subspecies lactis seed solution was inoculated into the fermentation culture medium at an inoculation rate of 8%, and cultured at 30°C for 12 h to obtain the OD 600 The first fermentation liquid with a value of 8 and a lactic acid content of 8 g / L was inoculated with the cultured Pediococcus acidilactici seed liquid at a 15% inoculation rate, 30 g / L of glucose was added thereto, and the culture was continued at 30°C for 12 h to obtain an OD 600 The value is 12 and the second fermentation broth has a lactic acid content of 15g / L.

[0025] (3) Extraction and purification The pH value of the second fermentation liquid was adjusted to 2.0 using food-grade hydrochloric acid, kept at 60°C for 30 minutes, cooled to 40°C, and filtered using a ceramic membrane to obtain a filtrate; the ceramic membrane filtrate was concentrated by an ultrafiltration membrane with a molecular weight cutoff of 1000Da, with a concentration multiple of 10 times to obtain a concentrated solution; 10% maltodextrin was added to the concentrated solution, and dried using a spray drying tower to obtain a product, namely, glucose fermentation product.

[0026] Example 2 (1) Preparation of seed solution MRS liquid culture medium was prepared in advance, and the formula was that each liter of culture medium contained 10 g of peptone, 10 g of beef extract powder, 4 g of yeast powder, 15 g of glucose, 3 g of sodium acetate, 3 g of diammonium citrate, 1 g of Tween 80, 2 g of dipotassium hydrogen phosphate, 2 g of magnesium sulfate heptahydrate, and 0.2 g of manganese sulfate.

[0027] Lactococcus lactis subsp. lactis seed liquid: Pick a single colony of Lactococcus lactis subsp. lactis after activation, inoculate it into liquid MRS medium at a rate of 1%, and culture it in a 28°C incubator for 16 hours to obtain the OD 600 The culture solution with a value of 2 was inoculated into the seed tank at a 1% inoculation rate and fermented at 28°C for 8 h to obtain the OD 600 The value is 2 for Lactococcus lactis subsp. lactis seed liquid.

[0028] Seed liquid of Pediococcus acidilactici: Pick a single colony of activated Pediococcus acidilactici and inoculate it into liquid MRS medium at a rate of 1%, and culture it in a 28°C incubator for 16 hours to obtain the OD600 The culture solution with an OD600 value of 2 was inoculated into the seed tank at a 1% inoculation rate and cultured at 28°C for 8h to obtain the lactic acid Pediococcus seed solution with an OD600 value of 2.

[0029] (2) Fermentation broth preparation The fermentation culture medium was prepared in advance, and its formula was 15 g / L glucose, 5 g / L yeast extract powder, 1 g / L potassium dihydrogen phosphate, 1 g / L magnesium sulfate heptahydrate, and 2 g / L Tween 80.

[0030] The prepared Lactococcus lactis subspecies lactis seed solution was inoculated into the fermentation culture medium at a 10% inoculation rate and cultured at 30°C for 10 h to obtain the OD 600 The first fermentation liquid with a value of 7 and a lactic acid content of 7 g / L was inoculated with the cultured Pediococcus acidilactici seed liquid at a 20% inoculation rate into the first fermentation liquid, 25 g / L of glucose was added thereto, and the culture was continued at 28°C for 10 h to obtain the OD 600 The value is 10 and the lactic acid content is 12g / L in the second fermentation broth.

[0031] (3) Extraction and purification The pH value of the second fermentation liquid was adjusted to 4.0 using food-grade hydrochloric acid, kept at 80°C for 10 minutes, cooled to 40°C, and filtered using a ceramic membrane to obtain a filtrate; the ceramic membrane filtrate was concentrated 15 times using an ultrafiltration membrane with a molecular weight cutoff of 1000Da to obtain a concentrated solution; 8% maltodextrin was added to the concentrated solution, and dried using a spray drying tower to obtain a product, namely, glucose fermentation product.

[0032] Example 3 (1) Preparation of seed solution Prepare MRS liquid culture medium in advance, with the formula containing 15 g of peptone, 15 g of beef extract powder, 6 g of yeast powder, 20 g of glucose, 5 g of sodium acetate, 5 g of diammonium citrate, 2 g of Tween 80, 3 g of dipotassium hydrogen phosphate, 3 g of magnesium sulfate heptahydrate, and 0.3 g of manganese sulfate per liter of culture medium.

[0033] Lactococcus lactis subsp. lactis seed liquid: Pick a single colony of Lactococcus lactis subsp. lactis after activation, inoculate it into liquid MRS medium at a rate of 5%, and culture it in a 32°C incubator for 20 h to obtain the OD 600 The culture solution with a value of 4 was inoculated into the seed tank at a 5% inoculation rate and fermented at 32°C for 12 h to obtain the OD 600 A value of 4 for Lactococcus lactis subsp. lactis seed liquid.

[0034] Seed liquid of Pediococcus acidilactici: Pick a single colony of activated Pediococcus acidilactici and inoculate it into liquid MRS medium at a rate of 5%. Incubate it in a 32°C incubator for 20 h to obtain the OD600 The culture solution with an OD600 value of 4 was inoculated into the seed tank at a 5% inoculation rate and cultured at 32°C for 12 h to obtain a seed solution of Pediococcus acidilactici with an OD600 value of 4.

[0035] (2) Fermentation broth preparation The fermentation culture medium was prepared in advance, and its formula was 30 g / L glucose, 15 g / L yeast extract powder, 3 g / L potassium dihydrogen phosphate, 3 g / L magnesium sulfate heptahydrate, and 2 g / L Tween 80.

[0036] The prepared Lactococcus lactis subspecies lactis seed solution was inoculated into the fermentation culture medium at a rate of 15%, and cultured at 32°C for 8 h to obtain the OD 600 The first fermentation liquid with a value of 6 and a lactic acid content of 6 g / L was inoculated with the cultured Pediococcus acidilactici seed liquid at a 25% inoculation rate into the first fermentation liquid, 20 g / L of glucose was added thereto, and the culture was continued at 32°C for 8 h to obtain an OD 600 The second fermentation broth has a value of 8 and a lactic acid content of 10 g / L.

[0037] (3) Extraction and purification The pH value of the second fermentation liquid was adjusted to 3.0 using food-grade hydrochloric acid, kept at 70°C for 20 minutes, cooled to 50°C, and filtered using a ceramic membrane to obtain a filtrate; the ceramic membrane filtrate was concentrated 12 times using an ultrafiltration membrane with a molecular weight cutoff of 1000Da to obtain a concentrated solution; 8% maltodextrin was added to the concentrated solution, and dried using a spray drying tower to obtain a product, namely, glucose fermentation product.

[0038] Comparative Example 1 (1) Preparation of seed solution Prepare MRS liquid culture medium in advance, with the formula containing 5 g of peptone, 5 g of beef extract powder, 2 g of yeast powder, 10 g of glucose, 1 g of sodium acetate, 1 g of diammonium citrate, 2 g of Tween 80, 1 g of dipotassium hydrogen phosphate, 1 g of magnesium sulfate heptahydrate, and 0.1 g of manganese sulfate per liter of culture medium.

[0039] Lactococcus lactis subsp. lactis seed liquid: Pick a single colony of Lactococcus lactis subsp. lactis after activation, inoculate it into liquid MRS medium at a rate of 3%, and culture it in a 30°C incubator for 18 h to obtain the OD 600 The culture solution with a value of 3 was inoculated into the seed tank at a rate of 3% and fermented at 30°C for 10 h to obtain the OD 600 The value is 3 for Lactococcus lactis subsp. lactis seed liquid.

[0040] (2) Fermentation broth preparation The fermentation culture medium was prepared in advance, and its formula was 20 g / L glucose, 10 g / L yeast extract powder, 2 g / L potassium dihydrogen phosphate, 2 g / L magnesium sulfate heptahydrate, and 1 g / L Tween 80.

[0041] The prepared Lactococcus lactis subspecies lactis seed solution was inoculated into the fermentation culture medium at an inoculation rate of 8%, and cultured at 30°C for 12 h to obtain the OD 600 The fermentation liquid has a value of 8 and a lactic acid content of 8g / L.

[0042] (3) Extraction and purification The pH value of the fermentation liquid was adjusted to 2.0 using food-grade hydrochloric acid, kept at 60°C for 30 minutes, cooled to 40°C, and filtered using a ceramic membrane to obtain a filtrate; the ceramic membrane filtrate was concentrated by an ultrafiltration membrane with a molecular weight cutoff of 1000Da, with a concentration multiple of 10 times to obtain a concentrated solution; 10% maltodextrin was added to the concentrated solution, and dried using a spray drying tower to obtain a product, namely, glucose fermentation product.

[0043] Comparative Example 2 (1) Preparation of seed solution Prepare MRS liquid culture medium in advance, with the formula containing 5 g of peptone, 5 g of beef extract powder, 2 g of yeast powder, 10 g of glucose, 1 g of sodium acetate, 1 g of diammonium citrate, 2 g of Tween 80, 1 g of dipotassium hydrogen phosphate, 1 g of magnesium sulfate heptahydrate, and 0.1 g of manganese sulfate per liter of culture medium.

[0044] Seed liquid of Pediococcus acidilactici: Pick a single colony of activated Pediococcus acidilactici and inoculate it into liquid MRS medium at a rate of 3%. Incubate it in a 30°C incubator for 18 h to obtain the OD 600 The culture solution with an OD600 value of 3 was inoculated into the seed tank at a 3% inoculation rate and cultured at 30°C for 10 h to obtain a seed solution of Pediococcus acidilactici with an OD600 value of 3.

[0045] (2) Fermentation broth preparation The fermentation culture medium was prepared in advance, and its formula was 20 g / L glucose, 10 g / L yeast extract powder, 2 g / L potassium dihydrogen phosphate, 2 g / L magnesium sulfate heptahydrate, and 1 g / L Tween 80.

[0046] The prepared lactic acid Pediococcus seed solution was inoculated into the fermentation culture medium at a 15% inoculation rate and cultured at 30 °C for 12 h to obtain the OD 600 The fermentation broth has a value of 12 and a lactic acid content of 15g / L.

[0047] (3) Extraction and purification The pH value of the fermentation liquid was adjusted to 2.0 using food-grade hydrochloric acid, kept at 60°C for 30 minutes, cooled to 40°C, and filtered using a ceramic membrane to obtain a filtrate; the ceramic membrane filtrate was concentrated by an ultrafiltration membrane with a molecular weight cutoff of 1000Da, with a concentration multiple of 10 times to obtain a concentrated solution; 10% maltodextrin was added to the concentrated solution, and dried using a spray drying tower to obtain a product, namely, glucose fermentation product.

[0048] Test Case (1) Cultivation of sensitive bacteria: The sensitive bacteria of Gram-positive bacteria are Staphylococcus aureus, and the solid culture medium used is LB culture medium with a formula of 10 g / L peptone, 5 g / L yeast extract powder, 10 g / L sodium chloride, and 15-20 g / L agar powder.

[0049] The sensitive bacteria of Gram-negative bacteria are Pseudomonas aeruginosa, and the solid culture medium used is LB culture medium with a formula of 10 g / L peptone, 5 g / L yeast extract powder, 10 g / L sodium chloride, and 15-20 g / L agar powder.

[0050] (3) Prepare Staphylococcus aureus and Pseudomonas aeruginosa plates respectively, so that the final bacterial count is 10 5 CFU / mL. After the culture medium solidifies, use a 7 mm borer to punch 4 holes on each plate, remove the agar blocks and set aside.

[0051] (4) The glucose fermentation products obtained in Examples 1 to 3 and Comparative Examples 1 to 2 were diluted to 0.5 g / L, 1.0 g / L, 2.0 g / L, 4.0 g / L, 8.0 g / L, 16.0 g / L and 32.0 g / L respectively using sterile water for later use.

[0052] (5) Take 100uL of glucose fermentation products of different concentrations and add them to the pre-prepared Staphylococcus aureus and Pseudomonas aeruginosa perforated plates. After they are completely absorbed, place them in a 35-37℃ incubator and culture them overnight. Use a vernier caliper to measure the diameter of the inhibition zone. Detailed data are shown in Table 1.

[0053] Table 1 Antibacterial effect data of glucose fermentation products obtained in Examples and Comparative Examples

[0054] It can be seen from Table 1 that the glucose fermentation product prepared in the embodiment of the present invention has good antibacterial effect on Staphylococcus aureus and Pseudomonas aeruginosa. At the same time, it can be seen that under the same fermentation conditions, the glucose fermentation product prepared in Example 1 has a greater antibacterial effect on the two sensitive bacteria than the glucose fermentation product prepared by fermenting Lactococcus lactis subsp. lactis in Comparative Example 1 and the glucose fermentation product prepared by fermenting Pediococcus acidilactici in Comparative Example 2.

[0055] Although the present invention has been described in detail by way of preferred embodiments, the present invention is not limited thereto. Without departing from the spirit and essence of the present invention, a person of ordinary skill in the art may make various equivalent modifications or substitutions to the embodiments of the present invention, and such modifications or substitutions shall be within the scope of the present invention. Any person of ordinary skill in the art may easily conceive of changes or substitutions within the technical scope disclosed by the present invention, and such changes or substitutions shall be within the scope of protection of the present invention.

Claims

1. A method for preparing a glucose fermentation product having antibacterial activity, characterized in that: The steps include: (1) inoculating a Lactococcus lactis subspecies lactis seed liquid into a fermentation culture liquid containing glucose to obtain a first fermentation liquid; (2) inoculating the first fermentation liquid with the seed liquid of Pediococcus acidilactici, adding glucose, and fermenting to obtain the second fermentation liquid; (3) The pH of the second fermentation liquid is adjusted to acidic, and the glucose fermentation product is obtained after filtering, concentrating, and spray drying.

2. The method for preparing a glucose fermentation product having antibacterial activity according to claim 1, characterized in that: In step (1), the method for preparing Lactococcus lactis subsp. lactis seed solution comprises inoculating Lactococcus lactis subsp. lactis at an inoculation rate of 1% to 5% into MRS liquid culture medium, culturing at a temperature of 28 to 32° C. for 16 to 20 hours, and obtaining an OD 600 The culture solution with an OD value of 2-4 was inoculated into the seed tank at an inoculation rate of 1%-5%, and cultured at 28-32℃ for 8-12h to obtain the OD 600 Seed solution with a value of 2~4.

3. The method for preparing a glucose fermentation product with antibacterial activity according to claim 1, characterized in that: In step (1), the fermentation culture medium includes the following components in concentrations: 15-30 g / L glucose, 5-15 g / L yeast extract, 1-3 g / L potassium dihydrogen phosphate, 1-3 g / L magnesium sulfate heptahydrate, and 1-2 g / L Tween 80.

4. The method for preparing a glucose fermentation product having antibacterial activity according to claim 1, characterized in that: In step (1), the fermentation conditions include: the inoculation amount of Lactococcus lactis subspecies Lactis is 8% to 15%, and the fermentation temperature is 28 to 32°C for 8 to 12 hours to obtain OD 600 The first fermentation liquid has a value of 6~8 and a lactic acid content of 6~8g / L.

5. The method for preparing a glucose fermentation product having antibacterial activity according to claim 2, characterized in that: In step (2), the method for preparing the seed solution of Pediococcus acidilactici comprises inoculating Pediococcus acidilactici with an inoculation amount of 1% to 5% in MRS liquid culture medium, culturing at a temperature of 28 to 32° C. for 16 to 20 hours, and obtaining an OD 600 The culture solution with an OD600 value of 2~4 is added to the seed tank at an inoculation rate of 1%~5%, and cultured at 28~32℃ for 8~12h to obtain a seed solution with an OD600 value of 2~4.

6. The method for preparing a glucose fermentation product having antibacterial activity according to claim 5, characterized in that: MRS liquid culture medium was prepared according to the following concentrations of components: peptone 5~15 g / L, beef extract powder 5~15 g / L, yeast powder 2~6 g / L, glucose 10~20 g / L, sodium acetate 1~5 g / L, diammonium citrate 1~5 g / L, Tween 80 1~2 g / L, dipotassium hydrogen phosphate 1~3 g / L, magnesium sulfate heptahydrate 1~3 g / L, and manganese sulfate 0.1~0.3 g / L.

7. The method for preparing a glucose fermentation product having antibacterial activity according to claim 1, characterized in that: In step (2), the inoculation amount of the lactic acid Pediococcus seed solution is 15% to 25%, glucose is added at 20 to 30 g / L, and the mixture is fermented at a temperature of 28 to 32 °C for 8 to 12 h to obtain an OD 600 The second fermentation broth has a value of 8~12 and a lactic acid content of 10~15g / L.

8. The method for preparing a glucose fermentation product having antibacterial activity according to claim 1, characterized in that: In step (3), hydrochloric acid is used to adjust the pH of the second fermentation liquid to 2-4.

9. The method for preparing a glucose fermentation product having antibacterial activity according to claim 1, characterized in that: In step (3), the second fermentation liquid after pH adjustment is filtered using a ceramic membrane, and the filtrate after filtration is concentrated 10 to 15 times to obtain a concentrated liquid.

10. The method for preparing a glucose fermentation product having antibacterial activity according to claim 9, characterized in that: 5% to 10% maltodextrin is added to the concentrate and then spray-dried.

Images