CN115820456A - Bacillus coagulans for efficiently degrading zearalenone and application thereof - Google Patents

Abstract

The invention discloses bacillus coagulans for efficiently degrading zearalenoneBacillus coagulans) The bacillus coagulans is named as ASAG215, is preserved in the China Committee for culture Collection of microorganisms, and has the preservation number of CGMCC No.18368, and belongs to the field of biotechnology. The conditions for the optimal degradation effect are as follows:the initial concentration of Bacillus coagulans is 10 ⁸ CFU/mL, pH value of 6.6-7.0, culture temperature of 40-48 ℃, and rotation speed of 120-160 rpm. The strain degrades zearalenone with the concentration of 50 mu g/mL into a nontoxic product within 2h, and the degradation rate reaches more than 92%. The invention also provides a bacterial preparation containing the bacterial strain and used for degrading zearalenone, and application of the bacterial preparation. The preparation method of the bacterial preparation used by the invention is simple, does not contain antibiotic components, has no toxic or side effect, has no drug resistance and no pollution, and has obvious economic benefit and practical application value.

Description

Bacillus coagulans for efficiently degrading zearalenone and application thereof

Technical Field

The invention belongs to the technical field of beneficial microbial degradation, and particularly relates to bacillus coagulans capable of efficiently degrading zearalenone and application thereof.

Background

Zearalenone (ZEA) also called F-2 toxin is a lactone compound of 2, 4-dihydroxy benzoic acid and mainly prepared from Fusarium graminearumFusarium.graminearum) Fusarium roseum (F. Roseum) (II)F.roseum) And Fusarium oxysporum (F.), (F.oxysporum) And so on. ZEA has estrogen-like effect, and can be irreversibly combined with intrauterine estrogen receptor, thereby influencing reproductive physiology of animals. Estimated by the food and agriculture organization of the united nations, 25% of crops worldwide are contaminated with mycotoxins each year, wherein ZEA contamination is severe, and global livestock and poultry suffer economic losses of nearly billions of dollars each year due to the consumption of ZEA contaminated feed. The intake of ZEA-polluted feed by livestock and poultry causes the reduction of animal production performance and reproductive performance and reduces animal immunity-induced diseases. Meanwhile, ZEA can also remain in animal products such as meat, eggs and dairy products, and poses a great threat to human health through a food chain. Research shows that ZEA can be remained in sow milk, so that the red and swollen vulva of a newly born piglet can be caused.

In recent years, a large number of detoxification methods related to ZEA have been reported. There are mainly physical, chemical and biological methods. Physical methods and chemical methods are traditional ZEA detoxification methods, but the methods have the defects of incomplete detoxification, influence on feed palatability, loss of nutrient components, difficulty in large-scale production and the like, and are not widely applied. The microorganism and the ZEA method thereof degraded by the biological enzyme are concerned by researchers due to the advantages of safety, environmental protection, thorough detoxification, strong specificity and the like. At present, although researches report that fungi, bacteria and metabolic enzymes thereof can degrade ZEA, on one hand, due to the safety consideration, some microbial strains with high ZEA degrading activity cannot be directly applied to food or feed; on the other hand, the microbial degrading enzyme is difficult to be applied to actual production due to the problems of complex separation and purification process, unstable activity and the like.

In summary, in order to solve the problem of ZEA pollution in agricultural products, feed raw materials and feeds, it is necessary to separate and screen microbial strains capable of degrading ZEA safely and efficiently from natural resources, especially strains capable of being directly utilized in actual production, and further research the biological characteristics and toxicity of degradation products, so as to research and develop ZEA microbial strain preparations suitable for feed industry and reduce economic loss of breeding industry. Most of the strains involved in the degradation of ZEA are fungi (yeasts) or bacteria that do not allow their direct use in the actual production (Pseudomonas). In the prior art, the invention patent with publication number CN105385616A discloses a Bacillus subtilis ASAGF141 for degrading zearalenone, and the strain reacts for 6 hours to ensure that the degradation rate of ZEA with the final concentration of 20 mu g/mL reaches more than 90%. And the degradation time of the bacterial strain in the existing patent is longer, so that the ZEA can not be completely degraded before food is discharged out of the intestinal tract, and the degradation effect of the existing bacterial strain on the high-concentration ZEA is to be improved.

Disclosure of Invention

In order to overcome the defects in the prior art and solve the technical problems that the ZEA is long in degradation time, cannot be completely degraded before food is discharged out of an intestinal tract and is poor in degradation effect on high-concentration ZEA, the invention provides bacillus coagulans capable of rapidly and efficiently degrading zearalenone and application thereof.

The invention is realized by the following technical scheme.

A bacillus coagulans ASAG215 is classified as: bacillus coagulans bacterium (A), (B) and (C)Bacillus coagulans) The culture medium is preserved in China general microbiological culture Collection center with the preservation number of CGMCC No.18368 and the preservation unit address of: beijing CityWest road No.1 hospital No. 3 in morning sun, the preservation date is: 8 and 6 months in 2019. The bacillus coagulans ASAG215 (preservation number: CGMCC No. 18368) strain capable of efficiently degrading ZEA provided by the invention is separated from donkey intestinal contents of Taiyuan ancient intercropped donkey base in Shanxi province, and the ASAG215 still can be mutated or mutated. For example, mutagenized strains obtained by chemical agents such as Nitrosoguanidine (NTG), or physical methods such as UV, irradiation, provided that the characteristics of the ability to degrade ZEA are retained, are also part of the present invention.

Further, the bacillus coagulans ASAG215 strain grows on an LB culture medium, colonies are round, white, flat, irregular in edges, gram-positive bacteria, cells are rod-shaped, flagellate and telogenic spores are absent, the spores are 1.2-1.5 microns in diameter, are oval to columnar, and thalli do not expand obviously after the spores are formed. Glucose: +; sucrose: +; lactose: +; mannitol: +; starch hydrolysis: +; corn starch: +; indole production: +; methyl red: +; liquefaction of gelatin: +; urease: +; and (3) casein decomposition: +; growth at 50 ℃: +.

Extracting and amplifying the genome DNA of the strain according to the steps of a Takara bacterial genome DNA extraction kit and a PCR method, determining the full length of a 16SrRNA gene sequence to be about 1500bp, comparing the sequence at NCBI (national center for Biotechnology) by using Blast, and carrying out phylogenetic analysis on related sequences from a GenBank database, and finding that the sequence has 100 percent of homology with the AB362708.116SrRNA gene sequence of the bacillus coagulans, and combining physiological and biochemical characteristics to identify the bacillus coagulans.

A microbial inoculum for efficiently degrading zearalenone, wherein: the active ingredient of the microbial inoculum is bacillus coagulans ASAG215 or a mutant strain derived from the bacillus coagulans ASAG215, and the preservation number of the bacillus coagulans ASAG215 is CGMCC No.18368.

Further, the microbial inoculum is a liquid microbial inoculum or a solid microbial inoculum.

The preparation method of the microbial inoculum comprises the following steps:

(1) Activating 30% of glycerol and bacillus coagulans ASAG215 with the preservation number of CGMCC No.18368 or mutant strain liquid derived from the bacillus coagulans ASAG215 on a solid culture medium, wherein the volume ratio of the strain liquid to the glycerol is 1; the solid culture medium comprises the following components: the solid culture medium comprises the following components: 10g of peptone, 5g of yeast extract, 5g of sodium chloride, 20g of agar and 1000mL of distilled water, wherein the pH value is 6.5 to 7.0;

(2) Inoculating 1mL of the activated bacterial liquid obtained in the step (1) into 50mL of seed culture liquid, and culturing until the OD value is 0.7-0.8, and reaching the logarithmic phase to obtain a seed liquid; the seed culture solution comprises the following components: 10g of peptone, 60g of glucose, 5g of yeast extract ₄ ·7H ₂ O0.5g，CaCO ₃ 10g, 1000mL of distilled water, and 6.8 to 7.2 of pH value;

(3) Inoculating the seed solution obtained in the step (2) into a fermentation culture medium, and culturing until the seed solution reaches a stable period, wherein the OD value is 1.0 to 1.2, so as to prepare a liquid microbial inoculum; the fermentation medium comprises the following components: 10g of peptone, 10g of glucose, 6g of yeast extract powder, mgSO 6 ₄ ·7H ₂ O1.0g，K ₂ HPO ₄ ·3H ₂ 1000mL of O2.0g of distilled water, and the pH value is 6.5 to 7.0.

Further, the method comprises the steps of uniformly mixing the liquid microbial inoculum and the corncob powder according to the mass ratio of 1 to 5, adding a protective agent accounting for 2 to 5 percent w/v, uniformly stirring, and then carrying out spray drying to obtain a solid microbial inoculum; the spray drying conditions are as follows: the air inlet temperature is 160 to 180 ℃, the outlet temperature is 60 to 90 ℃, and the feeding speed is 1 to 1.5L/h.

The bacillus coagulans ASAG215 or the microbial inoculum is applied to degradation of zearalenone.

Further, the bacillus coagulans ASAG215 has an intracellular enzyme effect on zearalenone degradation.

Further, the degradation of zearalenone by bacillus coagulans ASAG215 comprises the following steps: initial concentration of Bacillus coagulans ASAG215 is 10 ⁸ CFU/mL, pH value of 6.6-7.0, culture temperature of 40-48 ℃, and rotation speed of 120rpm-160rpm. When the initial concentration of ZEA is 50 mug/mL, the degradation rate of the Bacillus coagulans reaches 92% after 2 hours.

The method for determining the degradation of ZEA active components by bacillus coagulans ASAG215 is carried out according to the following steps: and (3) applying fermentation liquor, somatic cells and intracellular extracts of bacillus coagulans ASAG215 to degrade ZEA. The degradation rate of the fermentation supernatant on ZEA is found to be remarkably higher than that of somatic cells and intracellular extracts, and the fact that the active components of the ZEA degraded by the bacillus coagulans ASAG215 are present in the fermentation supernatant is proved.

Further, when the bacillus coagulans liquid microbial inoculum is used for degrading zearalenone, the bacillus coagulans liquid microbial inoculum is sprayed on the zearalenone polluted grain or feed raw materials according to the mass ratio of 1 ⁸ CFU/mL。

Further, when the bacillus coagulans solid microbial inoculum is used for degrading zearalenone, the bacillus coagulans solid microbial inoculum is added into grains, feed raw materials or feed according to the addition amount of 0.05-0.10%, the mixture is uniformly mixed, and the number of living cells of the solid microbial inoculum reaches 10 ⁸ CFU/mL。

Further, the grains include corn, wheat, peanut meal, rice or sorghum and the like; the feed raw materials and the feed comprise corn, wheat, peanut meal, rice, sorghum and other feed raw materials and the feed processed by the corn, the wheat, the peanut meal, the rice, the sorghum and the like.

Compared with the prior art, the invention has the beneficial effects that:

1. the bacillus coagulans ASAG215 used in the invention can degrade ZEA efficiently and rapidly. When the initial concentration of ZEA is 50 mug/mL, the degradation rate of Bacillus coagulans ASAG215 reaches 95% after 2 hours;

2. the bacillus coagulans ASAG215 used in the invention can be directly used as a feed additive to be added into feed for use, does not damage the nutrient components in the feed, has no influence on the sensory quality of the feed, and has safe strains, low production cost, easy operation and high temperature resistance. Solves the problem of pollution of feed raw materials and feed ZEA, and improves the economic benefit of animal husbandry.

Drawings

FIG. 1 is a graph showing the efficiency of Bacillus coagulans ASAG215 in degrading zearalenone.

Detailed Description

The present invention will be described in further detail with reference to examples.

The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention. Unless otherwise specified, the examples follow conventional experimental conditions. In addition, it will be apparent to those skilled in the art that various modifications or improvements can be made to the material components and amounts in these embodiments without departing from the spirit and scope of the invention as defined in the appended claims.

The percent in the examples means% by mass unless otherwise specified; the percent of the solution refers to the grams of solute contained in 100 mL.

Example 1 isolation and characterization of Bacillus coagulans ASAG215 degrading ZEA

1. And (3) separating bacteria:

(1) After the donkeys in the Taiyuan ancient intercropping donkeys base in Shanxi province are slaughtered, the aseptic tube collects the intestinal contents and notes the information of collection name, place, time and the like. Putting 1g of intestinal contents in 10mL of separation buffer solution, centrifuging, taking supernatant, and diluting by 10, 100, 1000 and 1000 times step by using a concentration gradient method;

(2) Coating the intestinal content suspension liquid diluted by different concentrations on a solid flat plate, culturing for 36h at 42 ℃, selecting bacterial strains with different morphological characteristics, colors and sizes on the flat plate, carrying out flat plate scribing purification, inoculating the purified bacterial strains to carry out a ZEA degradation test, and analyzing to obtain a strain with the highest degradation efficiency, wherein the bacterial strain is numbered as ASAG215.

2. And (3) identification of bacteria:

(1) The strain ASAG215 is round, white, flat, irregular in edge, gram-positive bacteria on an LB culture medium, and cells are rod-shaped, have no flagella and have terminal spores. The diameter of the spore is 1.2 to 1.5 mu m, and the shape is elliptical to columnar. The thalli is not obviously expanded after the spores are formed; glucose: +; sucrose: +; lactose: +; mannitol: +; starch hydrolysis: +; corn starch: +; indole production: +; methyl red: +; liquefaction of gelatin: +; urease: +; and (3) casein decomposition: +; growth at 50 ℃: +. The biochemical characteristics conform to the characteristics of bacillus coagulans;

(2) The 16S rRNA gene sequence is obtained by PCR amplification, and the total length is about 1500 bp. After sequencing, the relevant sequences were obtained from the GenBank database using Blast alignment at NCBI and phylogenetic analysis, the sequencing results are shown in SEQ ID NO 1. The results show that the homology of the ASAG215 and the 16S rRNA of the bacillus coagulans (AB 362708.1) reaches 100 percent, and the gene analysis shows that the ASAG215 is the bacillus coagulans.

SEQ ID NO:1：

1~60 tagagtttga tcatggctca ggacgaacgc tggcggcgtg cctaatacat gcaagtcgtg

61~120 cggacctttt aaaagcttgc ttttaaaagg ttagcggcgg acgggtgagt aacacgtggg

121~180 caacctgcct gtaagatcgg gataacgccg ggaaaccggg gctaataccg gatagttttt

181~240 tcctccgcat ggaggaaaaa ggaaagacgg cttcggctgt cacttacaga tgggcccgcg

241~300 gcgcattagc tagttggtgg ggtaacggct caccaaggca acgatgcgta gccgacctga

301~360 gagggtgatc ggccacattg ggactgagac acggcccaaa ctcctacggg aggcagcagt

361~420 agggaatctt ccgcaatgga cgaaagtctg acggagcaac gccgcgtgag tgaagaaggc

421~480 cttcgggtcg taaaactctg ttgccgggga agaacaagtg ccgttcgaac agggcggcgc

481~540 cttgacggta cccggccaga aagccacggc taactacgtg ccagcagccg cggtaatacg

541~600 taggtggcaa gcgttgtccg gaattattgg gcgtaaagcg cgcgcaggcg gcttcttaag

601~660 tctgatgtga aatcttgcgg ctcaaccgca agcggtcatt ggaaactggg aggcttgagt

661~720 gcagaagagg agagtggaat tccacgtgta gcggtgaaat gcgtagagat gtggaggaac

721~780 accagtggcg aaggcggctc tctggtctgt aactgacgct gaggcgcgaa agcgtgggga

781~840 gcaaacagga ttagataccc tggtagtcca cgccgtaaac gatgagtgct aagtgttaga

841~900 gggtttccgc cctttagtgc tgcagctaac gcattaagca ctccgcctgg ggagtacggc

901~960 cgcaaggctg aaactcaaag gaattgacgg gggcccgcac aagcggtgga gcatgtggat

961~1020 taattcgaag caacgcgaag aaccttacca ggtcttgaca tcctctgacc tccctggaga

1021~1080 cagggccttc cccttcgggg gacagagtga caggtggtgc atggttgtcg tcagctcgtg

1081~1140 tcgtgagatg ttgggttaag tcccgcaacg agcgcaaccc ttgaccttag ttgccagcat

1141~1200 tcagttgggc actctaaggt gactgccggt gacaaaccgg aggaaggtgg ggatgacgtc

1201~1260 aaatcatcat gccccttatg acctgggcta cacacgtgct acaatggatg gtacaaaggg

1261~1320 ctgcgagacc gcgaggttaa gccaatccca gaaaaccatt cccagttcgg attgcaggct

1321~1380 gcaacccgcc tgcatgaagc cggaatcgct agtaatcgcg gatcagcatg ccgcggtgaa

1381~1440 tacgttcccg ggccttgtac acaccgcccg tcacaccacg agagtttgta acacccgaag

1441~1500 tcggtgaggt aacctttacg gagccagccg ccgaaggtgg gacagatgat tggggtgaag

1501~1542 tcgtaacaag gtagccgtat cggaaggtgc ggttggatca cc

Example 2 degradation of ZEA by Bacillus coagulans ASAG215

ZEA determination method:

detecting ZEA by high performance liquid chromatography under the following conditions of Agilent C ₁₈ Columns (4.6 mm. Times.150 mm. Times.5 μm); mobile phase: acetonitrile: water: methanol (46; flow rate: 1.0 mL/min; column temperature: 27C; detection wavelength: λ ex =274 nm, λ em =440 nm; sample injection amount: 20. μ L. And obtaining the ZEA content according to the peak area comparison standard curve.

2. Degradation of ZEA by Bacillus coagulans ASAG215

(1) Inoculating 1mL of the deposited Bacillus coagulans ASAG215 into 50mL of a sterilization medium (10 g of peptone, 5g of yeast extract, 5g of sodium chloride, 1000mL of distilled water, pH 6.5-7.0), culturing at 42 ℃ and 160rpm for 24h (OD value of 0.8), and taking 900 muL of fermentation culture solution (concentration of 10) ⁸ CFU/mL) was mixed with 100 μ L ZEA standard to a final ZEA standard concentration of 50 μ g/mL; meanwhile, the culture medium containing the same final concentration of ZEA is used as a control, samples are taken at reaction time of 0h, 2h, 4h, 6h, 8h, 16h and 24h respectively, and the ZEA concentration is determined;

(2) ZEA degradation rate (%) = (initial ZEA concentration-measured ZEA concentration after sampling)/initial ZEA concentration × 100%;

(3) And (4) analyzing results: FIG. 1 shows the effect of the strain of the invention on the degradation of ZEA at different times. The ZEA content in the stock culture solution gradually decreased with the increase of time by comparison with the control group. At 2h, the degradation rate for ZEA reached 92%, and at 8h the presence of ZEA was not detectable under laboratory conditions.

3. Determination of degradation of ZEA active ingredient by bacillus coagulans ASAG 215:

(1) Selecting 100mL of Bacillus coagulans ASAG215 fermentation liquor, centrifuging at 10000g for 10min in a refrigerated centrifuge at 4 ℃, and taking out supernatant for later use (placing in ice); washing the thallus cell precipitate twice with PBS buffer solution, re-dissolving in the buffer solution and placing in ice for later use; washing and redissolving the other thallus cell precipitate, crushing the thallus cell twice by using an ultrasonic cell crusher to release intracellular active substances, centrifuging at 12000g for 20min at 4 ℃, taking supernate, filtering by using a sterilized cellulose membrane with the thickness of 0.22 mu m to obtain an intracellular extract of the thallus, and placing the intracellular extract in ice for later use;

(2) Mixing 900 muL of fermentation supernatant (cell suspension, intracellular extract) with 100 muL of ZEA standard (final concentration is 50 mug/mL) respectively; meanwhile, a culture medium containing the ZEA with the same final concentration is used as a control, the ZEA concentration is measured after the reaction is carried out for 2 hours, and the degradation rate is calculated;

(3) And (4) analyzing results: the degradation rate of the fermentation supernatant on ZEA is obviously higher than that of the thallus cells and the intracellular extract, the 2h degradation rate of the fermentation supernatant on ZEA is 90.4 percent, and the thallus and the intracellular extract on AFB ₁ The degradation rates of (a) and (b) were 5.3% and 2.7%, respectively, demonstrating that the bacillus coagulans ASAG215 degraded the ZEA active ingredient present in the fermentation supernatant.

Example 3 preparation of liquid inoculant of ASAG215 for degradation of ZEA

Activating strains: ASAG215 or a mutant strain derived therefrom, which was deposited in 30% glycerol (bacteria solution: glycerol = 1), was inoculated on a solid medium, cultured at 40 ℃ for 24 hours, and the degradation rate of degrading ZEA was measured. Wherein: the solid culture medium comprises the following components: 10g of peptone, 5g of yeast extract, 5g of sodium chloride, 20g of agar and 1000mL of distilled water, wherein the pH value is 6.5 to 7.0;

seed culture: inoculating the activated bacterial liquid with the ZEA degradation rate reaching 92% in 2h to a liquid culture medium, and culturing until the OD value is 0.8 and the logarithmic phase is reached to obtain the standby seed liquid. Wherein: the liquid culture medium comprises the following components: 10g of peptone, 60g of glucose, 5g of yeast extract ₄ ·7H ₂ O 0.5g，CaCO ₃ 10g, 1000mL of distilled water, and 6.8 to 7.2 of pH; then, the above-mentioned strain was inoculated in a 10L seed tank at an inoculum size of 2% (1.1 kg/cm) after sterilization ² Pressure and high-pressure moist heat sterilization at 121 ℃), culturing at 45 ℃, stirring at 160rpm, and introducing sterile air into the culture medium for about 24 to 32 hours to a logarithmic phase, wherein the mass ratio of the sterile air to the culture medium is 1.

Fermentation culture: inoculating the seed solution into sterilized (1.1 kg/cm) in a 500L production tank at an inoculation amount of 2% ² Pressure and high-pressure moist heat sterilization at 121 ℃) to obtain a liquid microbial inoculum, wherein the viable count of the liquid microbial inoculum at least reaches 10 ⁸ CFU/mL. Wherein: the fermentation medium comprises the following components: 10g of peptone, 10g of glucose, 6g of yeast extract powder ₄ ·7H ₂ O 1.0g，K ₂ HPO ₄ ·3H ₂ 1000mL of O2.0g of distilled water, wherein the pH value is 6.5 to 7.0; the fermentation conditions were: the ventilation volume is 1 to 1.2, the stirring speed is 120 to 180 rpm, the culture temperature is 45 to 48 ℃, and the culture time is about 24 to 32h.

Example 4 preparation of AF-degrading ASAG215 solid inoculum

The ASAG215 liquid microbial inoculum produced in the example 3 and corncob powder are uniformly mixed according to the mass ratio of 1 to 5, the content of the protective agent is 2 to 5 w/v, and the mixture is uniformly stirred and then spray-dried. To obtain the solid microbial inoculum. The spray drying conditions are as follows: the air inlet temperature is 160 to 180 ℃, the outlet temperature is 60 to 90 ℃, and the feeding speed is 1 to 1.5L/h.

Example 5 degradation effect of asaga 215 liquid inoculant on ZEA in cereals

The liquid agent of ASAG215 (viable cell count is 10) produced in example 3 ⁸ CFU/mL) is sprayed in Zea polluted corn flour according to the mass ratio of 1The nutrient is sprayed to the corn flour polluted by AF in the same proportion to be used as a control group; after mixing uniformly, reacting for 6h at 40 ℃.

Respectively selecting and weighing 25 g of samples from the test group and the control group, placing the samples in a 250 mL conical flask, adding 5g of sodium chloride and 100mL of methanol aqueous solution (volume ratio is 6. 10mL of the filtrate was diluted with 40 mL of PBS buffer and then filtered. The filtrate was purified by ZEA immunoaffinity column (beijing, zhongweikang technologies ltd), and the results showed that the degradation rate of ASAG215 liquid microbial inoculum to ZEA flour contaminated by ZEA was 79.3%, and the control group had no degradation effect.

Example 6 degradation Effect of ASAG215 solid inoculant on ZEA in cereals

The ASAG215 solid microbial inoculum (the number of living cells reaches 10) prepared in the example 5 ⁸ CFU/mL) was added to the ZEA contaminated corn flour at 0.05, 0.10% addition, mixed well and reacted at 40 ℃ for 2h. The ZEA content of the ZEA contaminated corn flour with added solid inoculant and non-solidified inoculant was determined according to the method of example 5, and the results showed that the degradation rate of ZEA contaminated corn flour by ASAG215 solid inoculant was 89.92%.

Example 7 relief Effect of ASAG215 on porcine ZEA intoxication symptoms

Selecting 20 young sows with 35.21 + -0.11 kg weight, red and swollen vulva, length X big ternary hybridization in Du' a and Xia as long as 20, dividing into 4 groups, and each group has 5 sows. The method comprises the following steps: group 1: sow feed without zearalenone pollution; group 2: the zearalenone pollutes the feed of the sow; group 3: ASAG215 solid microbial inoculum (viable cell count up to 10) prepared in example 5 ⁸ CFU/mL) is added into the feedstuff of the sow polluted by zearalenone according to the addition amount of 0.10 percent; group 4: the ASAG215 solid inoculum prepared in example 5 was added to the zearalenone contaminated sow diet at an addition level of 0.30%.

After feeding for 7 days, the vulvar area and the red and swollen symptoms of the sows of each treatment group are counted, and the results are shown in the following table 1.

As can be seen from the data in Table 1, the bacterium preparation of the invention is added according to the proportion of 0.10 to 0.30 percent, the vulva area of the young sow is restored to a normal level, and the red and swollen symptom of the vulva is avoided, so that the influence of the zearalenone on the young sow is reduced, and the bacterium preparation has a good application prospect.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.

Claims (12)

1. The bacillus coagulans ASAG215 is preserved in the China general microbiological culture Collection center of the Committee for culture Collection of microorganisms with the preservation number as follows: CGMCC No.18368.

2. The bacillus coagulans ASAG215 of claim 1, wherein: the bacillus coagulans ASAG215 strain grows on an LB culture medium, the bacterial colony is circular, white, flat, irregular in edge, gram-positive bacteria, the cell is rod-shaped, has no flagella and terminal spores, the diameter of the spores is 1.2 to 1.5 mu m, the spores are oval to columnar, and the thalli do not expand obviously after the spores are formed.

3. A microbial inoculum for efficiently degrading zearalenone is characterized in that: the active ingredient of the microbial inoculum is bacillus coagulans ASAG215 or a mutant strain derived from the bacillus coagulans ASAG215, and the preservation number of the bacillus coagulans ASAG215 is as follows: CGMCC No.18368.

4. The microbial inoculum of claim 3, wherein: the microbial inoculum is a liquid microbial inoculum or a solid microbial inoculum.

5. A method for producing the microbial agent according to claim 3, characterized by comprising the steps of:

(1) Activating 30% of glycerol and bacillus coagulans ASAG215 with the preservation number of CGMCC No.18368 or mutant strain liquid derived from the bacillus coagulans ASAG215 on a solid culture medium, wherein the volume ratio of the strain liquid to the glycerol is 1; the solid culture medium comprises the following components: the solid culture medium comprises the following components: 10g of peptone, 5g of yeast extract, 5g of sodium chloride, 20g of agar and 1000mL of distilled water, wherein the pH value is 6.5 to 7.0;

(2) Inoculating 1mL of the activated bacterial liquid obtained in the step (1) into 50mL of seed culture liquid, and culturing until the OD value is 0.7-0.8, and reaching the logarithmic phase to obtain a seed liquid; the seed culture solution comprises the following components: 10g of peptone, 60g of glucose, 5g of yeast extract ₄ ·7H ₂ O0.5g，CaCO ₃ 10g, 1000mL of distilled water, and 6.8 to 7.2 of pH value;

(3) Inoculating the seed solution obtained in the step (2) into a fermentation culture medium, and culturing until the seed solution reaches a stable period, wherein the OD value is 1.0 to 1.2, so as to prepare a liquid microbial inoculum; the fermentation medium comprises the following components: 10g of peptone, 10g of glucose, 6g of yeast extract powder, mgSO 6 ₄ ·7H ₂ O 1.0g，K ₂ HPO ₄ ·3H ₂ O2.0g and 1000mL of distilled water, wherein the pH value is 6.5 to 7.0.

6. The method for producing a bacterial agent according to claim 5, characterized in that: the method also comprises the steps of uniformly mixing the liquid fungicide and the corncob powder according to the mass ratio of 1 to 5, adding a protective agent accounting for 2 to 5 percent w/v, uniformly stirring, and carrying out spray drying to prepare the solid fungicide; the spray drying conditions are as follows: the air inlet temperature is 160 to 180 ℃, the outlet temperature is 60 to 90 ℃, and the feeding speed is 1 to 1.5L/h.

7. Use of bacillus coagulans ASAG215 according to claim 1 or the microbial inoculum according to any one of claims 3 or 5 for degrading zearalenone.

8. Use according to claim 7, characterized in that: the bacillus coagulans ASAG215 has the degradation effect on zearalenone and is an intracellular enzyme.

9. Use according to claim 7, characterized in that: the degradation of zearalenone by bacillus coagulans ASAG215 comprises the following steps: initial concentration of Bacillus coagulans ASAG215 is 10 ⁸ CFU/mL, pH value of 6.6 to 7.0, culture temperature of 40 to 48 ℃, and rotation speed of 120rpm to 160rpm.

10. Use according to claim 7, characterized in that: when the bacillus coagulans liquid microbial inoculum is used for degrading zearalenone, the bacillus coagulans liquid microbial inoculum is sprayed on zearalenone polluted grains or feed raw materials according to the mass ratio of 1 ⁸ CFU/mL。

11. Use according to claim 7, characterized in that: when the bacillus coagulans solid microbial inoculum is used for degrading zearalenone, the bacillus coagulans solid microbial inoculum is added into grains, feed raw materials or feed according to the addition amount of 0.05-0.10%, and the mixture is uniformly mixed, wherein the number of living cells of the solid microbial inoculum is 10 ⁸ CFU/mL。

12. Use according to claim 7, characterized in that: when the poisoning symptom of zearalenone on sows is relieved, the bacillus coagulans solid microbial inoculum is added into feed in an adding amount of 0.10-0.30%, and the mixture is uniformly mixed, wherein the number of living cells of the solid microbial inoculum is 10 ⁸ CFU/mL。

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