CN117660250A

CN117660250A - Low-temperature lactobacillus and application thereof

Info

Publication number: CN117660250A
Application number: CN202311681463.4A
Authority: CN
Inventors: 杨惠清; 梁运祥; 刘洋洋; 杨轶成; 谢澳文; 张恒; 李金山; 朱曦; 李英俊; 梅余霞
Original assignee: Huazhong Agricultural University
Current assignee: Huazhong Agricultural University
Priority date: 2023-12-08
Filing date: 2023-12-08
Publication date: 2024-03-08
Anticipated expiration: 2043-12-08
Also published as: CN117660250B

Abstract

The invention discloses a low-temperature lactobacillus and application thereof, and relates to the field of fermented feed. The low-temperature lactobacillus is lactobacillus plantarum (Lactobacillus plantarum) Liang which is preserved in the China center for type culture Collection, with a preservation address of China, university of Wuhan, and a preservation number of CCTCC NO: m20231507. According to the invention, lactobacillus plantarum Liang with low temperature resistance, acid resistance and high growth speed is screened from the fermented grains of Xiaoqu liquor in Hubei Huang Danjin wine works, and verified that the lactobacillus plantarum Liang can remarkably reduce the low-temperature fermentation period of fermented feed (silage/silage) and improve the fermentation quality.

Description

Low-temperature lactobacillus and application thereof

Technical Field

The invention relates to the field of fermented feed, in particular to a low-temperature lactobacillus and application thereof.

Background

Because of the climate characteristics of the north of China, the winter time is long, the air temperature is low, and the forage grass season is unbalanced, so that forage grass supply is in shortage in winter, and the development of northern animal husbandry is seriously affected. Crop straw resources in China are rich, but are not reasonably utilized, and are usually burnt or discarded, so that environmental pollution and resource waste are caused. The crop straw is fed, so that the ecological environment can be protected, the problem of forage shortage in winter can be relieved, the development of the breeding industry is promoted, and huge economic benefits are brought.

The feed prepared by fermenting crop straws by lactic acid bacteria under anaerobic conditions has sour and fragrant smell, good palatability and high digestibility, the nutritional value of the straws is reserved to the maximum extent, the aerobic stability is high, and the storage time of the straws is effectively prolonged. In addition, lactic acid bacteria are used as probiotics, and the thallus and the metabolites thereof are beneficial to the gastrointestinal health of animals. Metabolites produced by lactobacillus fermentation, such as lactic acid, short chain fatty acid, extracellular polysaccharide and the like, can enhance the activity of rumen bacteria, inhibit the growth and reproduction of pathogenic bacteria in intestinal tracts, regulate intestinal flora and improve the feed efficiency and growth performance.

The optimal growth temperature of lactobacillus is 37 ℃, and when the temperature is lower than 28 ℃, the growth metabolism of the strain is affected. Due to northern climate, the harvesting time of crops is 9-10 months with lower air temperature, lactic acid bacteria cannot grow and reproduce rapidly and secrete a large amount of organic acid under the low temperature condition, the pH of the straw is reduced to a level for inhibiting the growth of spoilage microorganisms, and the storage and quality of the straw can be seriously affected. Therefore, the method for obtaining the lactobacillus suitable for the northern low-temperature fermentation condition has positive significance.

Disclosure of Invention

The invention aims to provide a low-temperature lactobacillus and application thereof, which are used for solving the problems in the prior art, wherein the low-temperature lactobacillus can obviously reduce the low-temperature fermentation period of fermented feed (silage/silage) and improve the fermentation quality.

In order to achieve the above object, the present invention provides the following solutions:

the invention provides a low-temperature lactobacillus which is lactobacillus plantarum (Lactispan bacillus) Liang, wherein the lactobacillus plantarum Liang is preserved in China center for type culture Collection, the preservation address is China, university of Wuhan, and the preservation number is CCTCC NO: m20231507.

The invention also provides application of the low-temperature lactobacillus in preparation of a low-temperature starter.

The invention also provides a low-temperature starter, which comprises the low-temperature lactobacillus.

The invention also provides application of the low-temperature lactobacillus or the low-temperature starter in preparing fermented feed at low temperature.

The invention also provides application of the low-temperature lactobacillus or the low-temperature starter in shortening the low-temperature fermentation period of the fermented feed.

The invention also provides application of the low-temperature lactobacillus or the low-temperature starter in improving the nutrition quality of the fermented feed.

Further, the fermented feed is silage fermented feed or silage fermented feed.

The invention also provides a method for preparing the fermented feed at low temperature, which comprises the step of preparing the fermented feed by fermenting the fermentation raw material at low temperature by utilizing the low-temperature lactobacillus.

The invention also provides a method for shortening the low-temperature fermentation period of the fermented feed, which comprises the step of fermenting the fermentation raw material at a low temperature by utilizing the low-temperature lactobacillus so as to reduce the fermentation period.

The invention also provides a method for improving the nutritional quality of the fermented feed, which comprises the step of fermenting the fermentation raw material at a low temperature by utilizing the low-temperature lactobacillus so as to improve the nutritional quality of the fermented feed.

The invention discloses the following technical effects:

the invention screens out a strain of Lactobacillus plantarum (Lactplatinum) Liang with low temperature resistance, acid resistance and high growth speed from the fermented grains of Xiaoqu liquor in Hubei Huang Danjin winery by using a physiological and biochemical method. The screened strain Liang and the control strain are respectively added into different straws, and are put into a low-temperature environment for anaerobic fermentation, the quality of the fermented straws is analyzed and compared after unsealing, and the result proves that the lactobacillus plantarum Liang can obviously reduce the low-temperature fermentation period of fermented feed (silage/silage) and improve the fermentation quality.

The lactobacillus plantarum Liang improves the quality of straw feed, has low cost, is safe and reliable, has low temperature requirement, has better effect compared with other feed fermenting agents especially in low-temperature environment, and overcomes the problem of poor feed fermentation caused by slow growth and slow acid production of lactobacillus under low-temperature condition.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 shows the growth curves of Lactobacillus plantarum Liang under conditions of 37 ℃ (A), 15 ℃ (B) and 10 ℃ (C);

FIG. 2 shows the pH profile of Lactobacillus plantarum Liang at 15℃and 10℃respectively.

Detailed Description

Various exemplary embodiments of the invention will now be described in detail, which should not be considered as limiting the invention, but rather as more detailed descriptions of certain aspects, features and embodiments of the invention.

It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. In addition, for numerical ranges in this disclosure, it is understood that each intermediate value between the upper and lower limits of the ranges is also specifically disclosed. Every smaller range between any stated value or stated range, and any other stated value or intermediate value within the stated range, is also encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded in the range.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference for the purpose of disclosing and describing the methods and/or materials associated with the documents. In case of conflict with any incorporated document, the present specification will control.

It will be apparent to those skilled in the art that various modifications and variations can be made in the specific embodiments of the invention described herein without departing from the scope or spirit of the invention. Other embodiments will be apparent to those skilled in the art from consideration of the specification of the present invention. The specification and examples of the present invention are exemplary only.

As used herein, the terms "comprising," "including," "having," "containing," and the like are intended to be inclusive and mean an inclusion, but not limited to.

Example 1

1. Isolation, screening, identification and preservation of strains

Separating low-temperature lactobacillus from the fermented grains of the Xiaoqu liquor of Hubei Huang Danjin winery:

1.1 isolation and seed protection of lactic acid bacteria

Taking 1g of fermented grain culture sample, performing gradient dilution with sterile physiological saline, and selecting 1×10 ^-3 、1×10 ^-4 、1×10 ^-5 Three dilutions, each of which is absorbed by 200 mu L of the solution and uniformly coated on the surface of a bromophenol purple-MRS solid flat plate, are subjected to three-parallel culture at 37 ℃ for 48 hours, and are picked up to enable the culture medium to be purified by a single colony which turns into yellow, and are subjected to continuous 3 times of streaking separation, so that isolated strains are obtained. It was subjected to gram staining, catalase test, and seed protection with 20% glycerol.

1.2 screening of Low temperature lactic acid bacteria

1.2.1 determination of growth characteristics at different temperatures

The isolated strain was activated and inoculated into MRS broth, and after inoculation, the strain was cultured in an incubator at 15℃and 10℃for 5 days, and OD values were measured at 600nm, and the results are shown in Table 1. Let OD <0.1 be-, OD <0.5 be +, OD <0.5 be ++, OD <1 be ++, OD >1 be ++.

TABLE 1 Table of Strain growth ability at 10℃and 15 ℃

The lactobacillus is screened according to the low-temperature environment, the lactobacillus plantarum Liang performs optimally, and compared with other strains, the lactobacillus plantarum Liang can rapidly start growth metabolism at the temperature of 10 ℃ and 15 ℃; culturing at 10deg.C for 72 hr to obtain OD ₆₀₀ The value can reach 1.257; culturing at 15deg.C for 48 hr to obtain OD ₆₀₀ The value can reach 1.442; culturing at 28deg.C for 24 hr to obtain OD ₆₀₀ The value can reach 2.118.

1.2.2 measurement of acid resistance of lactic acid bacteria

After the pH values of the prepared MRS broth culture media were adjusted to pH2.0, pH3.0 and pH4.0, respectively, with 1mol/L hydrochloric acid solution, the culture media were autoclaved at 115℃for 30 minutes, after which the strain Liang was inoculated in 1% inoculum size into the MRS broth culture media of pH2.0, pH3.0 and pH4.0, respectively, cultured in an incubator at 37℃for 3 hours, the viable count of 0 hours and 3 hours was measured by dilution coating and the survival rate was calculated. The results are shown in Table 2, and the results show that the strain Liang has excellent acid resistance and can be well adapted to the acidic environment of the fermented feed.

TABLE 2 survival rate of Lactobacillus plantarum Liang incubated at pH2.0, pH3.0, pH4.0 for 3h

pH value of	Bacterial count 0h (. Times.10) ⁸ cfu/mL)	3h bacterial count (. Times.10) ⁸ cfu/mL)	Survival rate
				2.0	44.67	10.25	22.9％
3.0	46.67	36	77.1％
				4.0	48	46.3	96.5％

1.3 identification of strains

The strain Liang is gram-positive bacillus, the catalase test is negative, and the colony morphology is white, raised, wet and slippery on the surface and regular on the edge of the colony.

The isolated strain was picked up and cultured in MRS liquid medium at 37℃for 24 hours, DNA was extracted with TIANamp Bacteria DNA Kit (Tiangen Biotechnology Co., ltd.) kit, PCR amplification was performed with 1492R (TACGGCTACCTTGTTACGACTT) and 27F (AGAGTTTGATCCTGGCTCAG) primers, and the amplified product was sent to WUHANQINGSHU Biotechnology Co., ltd. For 16S rRNA sequencing. And (3) comparing the sequencing results in an NCBI database, wherein the similarity of the strain Liang and lactobacillus plantarum (Lactplatinum sp.) is more than 99%, and the strain Liang and lactobacillus plantarum are of the same species.

The 16S amplification sequence (SEQ ID NO. 1) is as follows:

TTAGGCGGCTGGTTCCTAAAAGGTTACCCCACCGACTTTGGGTGTTACAAACTCTCATGGTGTGACGGGCGGTGTGTACAAGGCCCGGGAACGTATTCACCGCGGCATGCTGATCCGCGATTACTAGCGATTCCGACTTCATGTAGGCGAGTTGCAGCCTACAATCCGAACTGAGAATGGCTTTAAGAGATTAGCTTACTCTCGCGAGTTCGCAACTCGTTGTACCATCCATTGTAGCACGTGTGTAGCCCAGGTCATAAGGGGCATGATGATTTGACGTCATCCCCACCTTCCTCCGGTTTGTCACCGGCAGTCTCACCAGAGTGCCCAACTTAATGCTGGCAACTGATAATAAGGGTTGCGCTCGTTGCGGGACTTAACCCAACATCTCACGACACGAGCTGACGACAACCATGCACCACCTGTATCCATGTCCCCGAAGGGAACGTCTAATCTCTTAGATTTGCATAGTATGTCAAGACCTGGTAAGGTTCTTCGCGTAGCTTCGAATTAAACCACATGCTCCACCGCTTGTGCGGGCCCCCGTCAATTCCTTTGAGTTTCAGCCTTGCGGCCGTACTCCCCAGGCGGAATGCTTAATGCGTTAGCTGCAGCACTGAAGGGCGGAAACCCTCCAACACTTAGCATTCATCGTTTACGGTATGGACTACCAGGGTATCTAATCCTGTTTGCTACCCATACTTTCGAGCCTCAGCGTCAGTTACAGACCAGACAGCCGCCTTCGCCACTGGTGTTCTTCCATATATCTACGCATTTCACCGCTACACATGGAGTTCCACTGTCCTCTTCTGCACTCAAGTTTCCCAGTTTCCGATGCACTTCTTCGGTTGAGCCGAAGGCTTTCACATCAGACTTAAAAAACCGCCTGCGCTCGCTTTACGCCCAATAAATCCGGACAACGCTTGCCACCTACGTATTACCGCGGCTGCTGGCACGTAGTTAGCCGTGGCTTTCTGGTTAAATACCGTCAATACCTGAACAGTTACTCTCAGATATGTTCTTCTTTAACAACAGAGTTTTACGAGCCGAAACCCTTCTTCACTCACGCGGCGTTGCTCCATCAGACTTTCGTCCATTGTGGAAGATTCCCTACTGCTGCCTCCCGTAGGAGTTTGGGCCGTGTCTCAGTCCCAATGTGGCCGATTACCCTCTCAGGTCGGCTACGTATCATTGCCATGGTGAGCCGTTACCCCACCATCTAGCTAATACGCCGCGGGACCATCCAAAAGTGATAGCCGAAGCCATCTTTCAAGCTCGGACCATGCGGTCCAAGTTGTTATGCGGTATTAGCATCTGTTTCCAGGTGTTATCCCCCGCTTCTGGGCAGGTTTCCCACGTGTTACTCACCAGTTCGCCACTCACTCAAATGTAAATCATGATGCAAGCACCAATCAATACCAGAGTTCGTTCGACTGC。

1.4 Strain preservation

The strain Liang is preserved in China center for type culture Collection (CCTCC NO) at the 8 th month and 21 th year 2023, and the preservation address is China university of Wuhan, and the preservation number is CCTCC NO: m20231507.

2. Determination of growth curves

Activating and inoculating the strain Liang into MRS broth culture medium, respectively placing into culture boxes at 37 ℃, 15 ℃ and 10 ℃ for culture, culturing at 37 ℃ for 14 hours, sampling every 30min, and measuring OD value at 600 nm; culturing at 15deg.C for 4d, sampling every 12 hr, and measuring OD value at 600 nm; the cells were incubated at 10℃for 7 days, sampled every 24 hours, and OD was measured at 600 nm. The growth curve was plotted with the incubation time on the abscissa and the OD on the ordinate, and the results are shown in fig. 1.

The strain Liang can be started rapidly at 37 ℃ and is subjected to a stabilization period after 7 hours of fermentation; entering a logarithmic growth phase after 12 hours at 15 ℃ and entering a stationary phase within 72 hours; at 10 ℃, the growth phase enters after 24 hours, and the stabilization phase enters within 120 hours. The adaptation phase and the logarithmic growth phase of lactobacillus plantarum are prolonged with the decrease of the ambient temperature, but the OD values finally reached are consistent.

3. Determination of acid production Rate

The strain Liang was activated and inoculated in MRS broth, and after inoculation, placed in 15℃and 10℃incubators, respectively, for cultivation. Culturing at 15deg.C for 4d, sampling every 12 hr; culturing at 10deg.C for 7d, sampling every 24 hr. The pH value in the sample was measured by using a calibrated METTLER TOLEDO FE K pH meter, the pH value of the sample was plotted on the ordinate with the incubation time on the abscissa, and the pH change curve was plotted, and the result is shown in FIG. 2.

The results showed that the pH of the Lactobacillus plantarum Liang broth dropped rapidly to 4.6 within 48 hours at 15 ℃; the pH of the broth was reduced to 4.0 within 72 hours at 10deg.C, and eventually remained stable at pH 3.6.

4. Determination of lactic acid, acetic acid and propionic acid content in lactic acid bacterium fermentation broth

The lactic acid, acetic acid and propionic acid contents of the lactic acid bacteria fermentation broth were measured by an Aglient 1200 high performance liquid chromatograph, and the results are shown in Table 3. Using an Aminex HPX-87H chromatographic column at 40 ℃; using a differential refractive detector; the detector temperature is 35 ℃; the flow rate of the mobile phase is 0.6mL/min; mobile phase 5mmol/LH ₂ SO ₄ Filtering the solution with a 0.45 μm filter membrane by a vacuum pump, and performing ultrasonic treatment for 20 min.

Lactic acid, acetic acid and propionic acid standard starter preparation:

preparing chromatographic grade standard substances of lactic acid, acetic acid, propionic acid and butyric acid, weighing 1g of the chromatographic grade standard substances of acetic acid and propionic acid, dissolving the chromatographic grade standard substances with ultrapure water, and fixing the volume to 100mL to prepare 10g/L standard stock solution; 4g of lactic acid standard substance was weighed, dissolved in ultrapure water and fixed to 100mL to prepare 40g/L standard stock solution. The standard stock solution was diluted to the corresponding working solution and all samples were filtered with a 0.22 μm filter before liquid phase sampling. Lactic acid working solution concentration: 0.5g/L,1.0g/L, 2.0g/L, 5.0g/L, 10.0g/L, 40.0g/L; acetic acid and propionic acid working solution concentration: 0.1g/L, 0.5g/L,1.0g/L, 2.0g/L, 5.0g/L. And drawing a standard curve by taking the concentration of the standard substance as an abscissa and the peak area as an ordinate. The components of each peak in the peak diagram of the sample are determined according to the peak time of the standard substance, and the contents of lactic acid, acetic acid and propionic acid in the lactobacillus fermentation broth can be determined according to the peak area of each component.

The lactobacillus fermentation supernatant is filtered by a 0.22 mu m filter membrane to prepare an upper sample, and the sample injection amount of the upper sample is 20 mu L. The components of each peak in the peak diagram of the sample are determined according to the peak time of the standard substance, and the contents of lactic acid, acetic acid and propionic acid in the lactobacillus fermentation broth can be determined according to the peak area of each component.

TABLE 3 lactic acid, acetic acid and propionic acid content in Lactobacillus plantarum Liang fermentation supernatant

Strain	Lactic acid (g/L)	Acetic acid (g/L)	Propionic acid (g/L)
				Lactobacillus plantarum Liang	17.30	3.67	0.30

5. Determination of bacteriostatic Activity

Preparation of an indicator bacterium suspension:

coli, salmonella, listeria and pseudomonas aeruginosa are inoculated into sterilized LB or MRS broth medium respectively, shake cultured for 24 hours at 37 ℃, and then diluted into bacterial suspensions with sterile water.

Preparing lactobacillus filtrate:

taking out the strain Liang from the refrigerator at the temperature of minus 80 ℃, inoculating the strain Liang into an MRS broth culture medium after overnight activation and propagation, standing and culturing for 24 hours at the temperature of 37 ℃, centrifuging for 10 minutes at the speed of 10000rpm, taking supernatant, passing through a filter membrane of 0.22 mu m, and taking filtrate for an antibacterial test.

Preparation of detection plates:

placing the prepared LB agar medium in an autoclave, sterilizing for 20min at 121 ℃, pouring 20mL of the medium into a sterilized disposable plate, solidifying the plate, drying the water thoroughly, sucking 200 mu L of the indicator fungus suspension on the plate by a pipette, and uniformly coating the plate with a sterilized glass triangular rod. The plates coated with the indicator fungus suspension were perforated with a sterilized 6mm punch and the liquid was aspirated from the wells, 4 wells were punched per plate, and 100 μl of lactic acid bacteria filtrate was added to each well. Placing the plate in a refrigerator at 4 ℃ for 4 hours, culturing for 24 hours at 37 ℃ and observing whether a bacteriostasis ring exists around the hole, performing 3 times of parallelization for each test, measuring the diameter of the bacteriostasis ring and taking an average value. The bacteriostasis diameter is more than or equal to 20mm and is marked as extremely sensitive "++ +"; the antibacterial diameter of 15mm or less and 20mm is high sensitivity "++"; the antibacterial diameter of 10mm or less and 15mm is the sensitization "+"; antibacterial diameters < 10mm are hypoallergenic or ineffective "-". The inhibition of Salmonella, E.coli, listeria monocytogenes and Pseudomonas aeruginosa by Lactobacillus plantarum Liang is shown in Table 4.

TABLE 4 inhibition of Lactobacillus plantarum Liang against Salmonella, E.coli, listeria monocytogenes and Pseudomonas aeruginosa

Strain	Salmonella bacteria	Coli bacterium	Listeria monocytogenes	Pseudomonas aeruginosa
					Lactobacillus plantarum Liang	+	++	++	+++

Example 2

In this example, two commercial low temperature silage ferments were selected for comparison

The tests are divided into a control group, a test group I (commercial low-temperature yellow storage starter of a certain company), a test group II (commercial low-temperature composite lactobacillus starter of a certain company) and a test group III (lactobacillus plantarum Liang bacterial liquid).

Cutting previously air-dried corn stalk into 2cm pieces according to 1×10 ⁶ cfu/g. The moisture of the straw feed after the bacterial liquid is added is controlled at 55 percent, and the straw feed is filled into polyethylene silage bags according to the standard of 200g per bag, and is vacuumized for anaerobic fermentation. Three replicates of each treatment were stored at 3℃for 15 days.

Fermentation quality analysis: after the silage bag is unsealed, 20g of the evenly mixed fermentation straw is put into a polyethylene sealing bag, 180mL of sterile water is added, the mixture is evenly mixed, soaked for 1h at 10 ℃, and 20mL of the mixture is taken after being evenly mixed again and centrifuged for 1min at 800 rpm. The supernatant was taken and the pH of the supernatant was measured by a pH meter, and the results are shown in Table 5.

TABLE 5 pH Change during yellow storage fermentation

The corn straw after anaerobic fermentation is bright yellow, has obvious sour and fragrant flavor and has moist texture.

Example 3

In this example, two commercial low temperature silage ferments were selected for comparison.

The tests are divided into a control group, a test group I (commercialized low-temperature silage starter for a certain company), a test group II (commercialized low-temperature composite lactobacillus starter for a certain company) and a test group III (lactobacillus plantarum Liang bacterial liquid).

Crushing whole silage corn by a kneader, and respectively spraying corresponding lactobacillus preparations on the silage corn in test groupsThe addition amount of the corn is 10 according to the commodity instruction ⁶ cfu/gram corn stalk, treating the control group with equal amount of sterile physiological saline, mixing uniformly, weighing 200g, packaging into silage bags, compacting, sealing, fermenting at 3deg.C for 30d, unsealing, sampling, analyzing silage fermentation quality and nutrient content, and measuring.

(1) Sensory evaluation. And evaluating according to silage quality evaluation standard.

Silage of test group III shows yellowish green color, has luster, and has faint scent of fermented lactic acid. The stem leaf structure is kept good.

(2) And (5) fermentation quality measurement. Mixing 20g of silage samples, adding 180mL of sterile water, mixing, soaking for 1h at 10 ℃, mixing again, and centrifuging for 1min at 8000rpm with 20mL of mixed solution. The supernatant was taken, the pH value of the supernatant was measured by a pH meter, and the contents of lactic acid and acetic acid were measured by a high performance liquid chromatograph, and the results are shown in Table 6.

TABLE 6 pH, lactic acid and acetic acid content variation during silage fermentation

After the lactobacillus plantarum Liang bacterial liquid is fermented for 30 days at low temperature, the pH values of a control group and a test group are obviously reduced, and compared with other groups, the lactic acid content of a test group III is highest; the content of acetic acid was also significantly increased compared to the control group.

(3) Determination of nutritional quality

Mixing each bag of silage sample uniformly, taking 20g, drying at 65 ℃ and crushing to 40 meshes. The contents of Dry Matter (DM), crude Protein (CP), neutral washing fiber (NDF), acid washing fiber (ADF), soluble carbohydrate (WSC) and crude Ash (Ash) were measured, and the results are shown in table 7. Crude Protein (CP): measuring by a Kjeldahl nitrogen determination instrument; neutral wash fiber (NDF) and acid wash fiber (ADF): performing a Van der Waals washing fiber analysis method; coarse Ash (Ash): the burning method is adopted for measurement; soluble Carbohydrates (WSC): the determination was performed using an anthrone-sulfuric acid colorimetric method.

TABLE 7 chemical composition of fresh straw and post-fermentation silage

Note that: the other indexes are based on dry matters except the dry matters.

The results show that the dry matter mass consumption of the test group III is minimal compared with the other groups, and the crude protein content is obviously improved compared with fresh straws.

The above embodiments are only illustrative of the preferred embodiments of the present invention and are not intended to limit the scope of the present invention, and various modifications and improvements made by those skilled in the art to the technical solutions of the present invention should fall within the protection scope defined by the claims of the present invention without departing from the design spirit of the present invention.

Claims

1. The low-temperature lactobacillus is lactobacillus plantarum (Lactiplantibacillus plantarum) Liang, and the lactobacillus plantarum Liang is preserved in China center for type culture Collection (China, university of Wuhan and Wuhan with a preservation number of CCTCC NO: m20231507.

2. Use of a strain of the low temperature lactic acid bacterium according to claim 1 in the preparation of a low temperature starter.

3. A low temperature starter comprising the low temperature lactic acid bacterium according to claim 1.

4. Use of a strain of the low temperature lactic acid bacteria of claim 1 or the low temperature starter of claim 3 for the low temperature preparation of a fermented feed.

5. Use of a strain of the low temperature lactic acid bacteria of claim 1 or the low temperature starter of claim 3 for shortening the low temperature fermentation period of a fermented feed.

6. Use of a strain of the low temperature lactic acid bacteria of claim 1 or the low temperature starter of claim 3 for improving the nutritional quality of a fermented feed.

7. The use according to any one of claims 4 to 6, wherein the fermented feed is silage or silage.

8. A method for preparing a fermented feed at a low temperature, comprising the step of fermenting a fermentation raw material at a low temperature by using the low-temperature lactic acid bacterium according to claim 1, thereby preparing the fermented feed.

9. A method for shortening the low-temperature fermentation period of a fermented feed, comprising the step of subjecting a fermentation raw material to low-temperature fermentation using the low-temperature lactic acid bacterium according to claim 1 to reduce the fermentation period.

10. A method for improving the nutritional quality of a fermented feed, comprising the step of low-temperature fermenting a fermentation raw material with the low-temperature lactic acid bacterium according to claim 1 to improve the nutritional quality of the fermented feed.