A composite microbial preparation for solid excrement degradation, and a preparation method and application thereof

Abstract

This invention discloses a composite microbial preparation for solid fecal degradation, its preparation method, and its application, belonging to the field of microbial preparation technology. The composite microbial preparation comprises a composite microbial agent and an exogenous composite enzyme preparation; the composite microbial agent includes laccase-producing bacteria, keratinase-producing bacteria, auxiliary degradation bacteria, and composite probiotics; the exogenous composite enzyme preparation includes cellulase, neutral protease, and xylanase. This invention employs a mixed strategy of "exogenous enzyme + enzyme-producing bacteria," rapidly decomposing cellulose, protein, and hemicellulose in the initial stage of composting by adding exogenous cellulase, protease, and xylanase, providing readily available carbon and nitrogen sources for the microorganisms, shortening the composting start-up time to less than 24 hours; simultaneously, the laccase-producing bacteria and keratinase-producing bacteria continuously produce laccase and keratinase during composting, achieving deep degradation of lignin and keratin. This invention has advantages such as rapid start-up, continuous degradation, good deodorization effect, high nitrogen retention rate, and low cost, and has good prospects for industrial application.

Description

Technical Field

[0001] This invention relates to the field of microbial preparation technology, and more specifically, to a composite microbial preparation for solid fecal degradation, its preparation method and application, particularly a composite microbial preparation using exogenous enzymes and enzyme-producing bacteria in synergistic supply. Background Technology

[0002] With the large-scale and intensive development of livestock and poultry farming, the treatment of large quantities of solid manure has become a key issue restricting the sustainable development of the industry. Improper treatment not only causes serious environmental pollution but also wastes the organic matter and nutrients in the manure. Aerobic composting using compound microbial agents is the main technical means to achieve the harmless and resource-based treatment of solid manure.

[0003] Currently, compound microbial agents used for fecal degradation mainly face the following technical problems: First, the active ingredients in microbial agents are limited, resulting in limited degradation efficiency. Existing microbial agents mainly rely on enzymes produced by the metabolism of microorganisms to degrade organic matter in feces. However, microbial enzyme production requires a long adaptation period, and composting starts slowly, typically requiring 48-72 hours to raise the temperature to above 50°C. Furthermore, they are insufficient in degrading recalcitrant substances in feces, such as lignin and keratin.

[0004] Second, the cost of exogenous enzyme preparations is high. In recent years, some technologies have begun to explore adding exogenous enzyme preparations to microbial agents to improve degradation efficiency. For example, patent CN202410498901.1 discloses a microbial-enzyme co-fermentation composition that achieves co-fermentation by adding laccase, fig protease, and phosphatase. However, the high cost of exogenous enzyme preparations hinders large-scale application.

[0005] Third, existing technologies are insufficiently targeted at the recalcitrant components in manure. In addition to conventional cellulose and protein, solid manure contains a high proportion of lignin (5-15%) and keratin (up to 15% in chicken manure). Lignin has a stable structure and is difficult to decompose by conventional microorganisms; keratin contains a large number of disulfide bonds, making it difficult for common proteases to effectively degrade. Existing technologies are generally inadequate in processing these two substances, affecting the maturity and quality of compost products.

[0006] Fourth, the timing of enzyme production by microorganisms and the interaction between exogenous enzymes lacks a systematic design. In existing technologies, neither pure microbial agents nor synergistic microbial-enzyme schemes adequately consider the timing of different enzymes' action at different stages of composting, resulting in low enzyme utilization efficiency.

[0007] To address the aforementioned issues, this invention provides an innovative hybrid strategy: some key enzymes are added exogenously for rapid initiation in the initial stage of composting; another portion of key enzymes are produced in situ by specific enzyme-producing bacteria during composting for the continuous degradation of recalcitrant substances. Through the temporal synergy between exogenous enzymes and enzyme-producing bacteria, both rapid initiation and continuous degradation are ensured. Summary of the Invention

[0008] The present invention aims to overcome the shortcomings of the prior art and provide a solid fecal degradation compound microbial preparation, its preparation method and application.

[0009] In a first aspect, the present invention provides a solid fecal degradation compound microbial preparation. It includes: (1) Compound microbial agents, including laccase-producing bacteria, keratinase-producing bacteria, auxiliary degradation bacteria and compound probiotics; The laccase-producing bacteria were selected from white-rot fungi ( Phanerochaete chrysosporium ) or Yunzhi ( Trametes versicolor ); Keratin-producing bacteria were selected from Bacillus licheniformis ( Bacillus licheniformis ), the auxiliary degrading bacteria include Bacillus cereus ( Bacillus cereus ) and yeast ( Saccharomyces cerevisiae The compound probiotic is composed of lactic acid bacteria, photosynthetic bacteria, and actinomycetes; (2) Exogenous complex enzyme preparations, including cellulase, neutral protease and xylanase; The laccase-producing bacteria and keratinase-producing bacteria produce laccase and keratinase in situ during the degradation of solid feces. The exogenous compound enzyme preparation plays a role in the early stage of composting, providing an effective carbon and nitrogen source for the rapid reproduction of microorganisms.

[0010] Preferably, the mass ratio of the compound microbial agent to the exogenous compound enzyme preparation is (10-15):(3-6).

[0011] Preferably, the viable count of the laccase-producing bacteria is ≥1×10⁻⁶. 8 CFU / g, the viable count of the keratinase-producing bacteria is ≥1×10⁻⁶. 9 CFU / g, the viable count of the *Bacillus cereus* is ≥2×10¹ 0 CFU / g, the viable count of the yeast is ≥1×10¹ 0 CFU / g, the total viable count of the compound probiotics is ≥1×10⁻⁶. 9 CFU / g.

[0012] Preferably, the compound microbial preparation further includes a matrix carrier, which is one or more of wheat bran, rice bran, and corn flour.

[0013] Preferably, the compound microbial preparation comprises the following raw materials in parts by weight: Matrix components: 55-75 parts wheat bran, 16.5-24.5 parts rice bran or rice husk powder, and 15-30 parts corn flour or starch; Nutritional composition: 5-15 parts bovine bone peptone, 3-6 parts brown sugar, 0.5-1.5 parts potassium dihydrogen phosphate; Microbial agent components: 1-3 parts laccase-producing bacteria, 2-5 parts keratinase-producing bacteria, 2-6 parts Bacillus cereus, 1.5-4.5 parts yeast, and 1.5-4.5 parts compound probiotics; Enzyme preparation components: 0.5-1.5 parts cellulase, 0.2-0.8 parts neutral protease, and 0.2-0.8 parts xylanase.

[0014] Secondly, the present invention provides a method for preparing the above-mentioned compound microbial preparation, comprising the following steps: (1) Laccase-producing bacteria, keratinase-producing bacteria, Bacillus cereus, yeast, and compound probiotics were cultured in liquid fermentation until the number of live bacteria reached the required level. (2) Mix the cultured bacterial solutions in proportion and collect the bacterial cells by centrifugation; (3) Grind wheat bran, rice bran and corn flour into 80-100 mesh, dry them to a moisture content of ≤12%, and mix them evenly with bovine bone peptone, brown sugar and potassium dihydrogen phosphate to obtain a matrix carrier; (4) Mix the bacterial cells collected in step (2) with the substrate carrier in step (3) and dry them at a low temperature of 35-45℃ until the water content is ≤10% to obtain a composite microbial agent; (5) Mix cellulase, neutral protease and xylanase in a certain proportion to obtain an exogenous complex enzyme preparation; (6) Package the compound microbial inoculant and the exogenous compound enzyme preparation separately.

[0015] Thirdly, the present invention provides a method for applying the above-mentioned compound microbial preparation, comprising the following steps: (1) Enzyme pre-degradation stage: Mix exogenous compound enzyme preparation with solid feces at a mass ratio of 1:500-1:1000, adjust the moisture content to 50%-60%, control the temperature at 40-50℃, and let it stand for 2-4 hours to degrade the cellulose, protein and hemicellulose in the feces into small molecules. (2) Activation and inoculation stage: Add all the compound microbial agents and activate them at 35-45℃ for 1-2 hours to preferentially activate Bacillus cereus and achieve step-by-step and orderly activation of the bacterial community.

[0016] (3) Composting fermentation stage: After inoculation, the material is piled into strips. First, the temperature is controlled at 35~42℃ for medium-temperature degradation for 3~4 days to ensure the activity of white rot fungi to degrade lignin. Then, the temperature is naturally raised to 55~65℃ for high-temperature composting for 3~4 days. When the temperature exceeds 65℃, the pile is turned over. The total fermentation cycle is 10~15 days. The pile is turned over once a day for the first 3 days, and then once every 2~3 days thereafter.

[0017] Preferably, in step (1), the pH is controlled at 6.5-7.5 during the enzymatic hydrolysis process, and the mixture is stirred once every 30 minutes.

[0018] Preferably, in step (3), the compost pile is turned over once a day for the first 3 days of fermentation, and then once every 2-3 days thereafter.

[0019] Beneficial effects The compound microbial agent of the present invention has the following significant advantages: This invention employs a functional microbial community design, and for the first time constructs a composite microbial system dominated by a core degrading microbial community and synergistically supported by multi-target functional microbial communities, achieving integrated fecal degradation and multi-target pollution control. Specifically, this invention addresses the decomposition challenges of lignin and keratin, two recalcitrant substances, through the synergistic combination of laccase-producing bacteria (white-rot fungi or Trametes versicolor) and keratinase-producing bacteria (Bacillus licheniformis); the auxiliary degrading microbial community composed of Bacillus cereus and yeast rapidly decomposes cellulose, protein, and hemicellulose in the early stages of composting, providing readily available carbon and nitrogen sources for the entire microbial community; and the composite probiotic community composed of lactic acid bacteria, photosynthetic bacteria, and actinomycetes in a 2:1:1 ratio creates a suitable microecological environment, inhibits the proliferation of putrefactive bacteria, and provides growth factors. The various bacterial communities form a metabolic complementarity and synergistic effect: Bacillus cereus decomposes large protein molecules to produce small peptides and amino acids, providing nutrient substrates for other functional bacterial communities; photosynthetic bacteria utilize ammonia nitrogen to synthesize amino acids, reducing ammonia volatilization; lactic acid bacteria produce acid to inhibit the growth of ammonia-producing bacteria; laccase-producing bacteria secrete laccase, which catalyzes the addition reaction of phenols and ammonia to form a humic-nitrogen complex, fixing ammonia nitrogen in the humic material. This systematic design overcomes the technical shortcomings of existing technologies, such as simple bacterial community mixing, single function, and lack of synergy, achieving integrated functions such as efficient degradation of organic matter in feces, ammonia emission reduction, nitrogen retention, and decomposition of recalcitrant substances.

[0020] This invention employs a hybrid strategy of "exogenous enzymes + enzyme-producing bacteria" and a time-sequential synergistic process of exogenous enzymes and microbial strains to achieve rapid initiation and continuous degradation of compost. By adding exogenous cellulase, neutral protease, and xylanase, cellulose, protein, and hemicellulose are rapidly decomposed in the early stages of composting, providing readily available carbon and nitrogen sources for the microorganisms, shortening the composting initiation time to less than 24 hours. Laccase-producing and keratinase-producing bacteria continuously produce laccase and keratinase during composting, achieving deep degradation of lignin and keratin, with lignin reaching over 30% and keratin over 45%. Simultaneously, this invention uses a step-by-step activation process to achieve orderly activation and synergistic symbiosis of the microbial community: first, Bacillus cereus is added and statically activated, allowing its spores to germinate in a directed manner and initiating protease synthesis; the resulting amino acids and other small molecules provide nutrients for the subsequently added microbial community. Then, laccase-producing bacteria, keratinase-producing bacteria, and a compound probiotic are added and statically activated, forming an orderly microbial succession relationship. This temporal co-culture design solves the problem of competitive inhibition in multi-species co-culture, resulting in a complex microbial community with stronger resistance to ammonia nitrogen and acid / alkali.

[0021] This invention's microbial agent boasts low raw material costs and a simple preparation process, making it suitable for large-scale application. The formula primarily utilizes agricultural byproducts such as wheat bran, rice bran, and corn flour as the matrix carrier, supplemented with conventional raw materials like industrial-grade bovine bone peptone, brown sugar, and potassium dihydrogen phosphate. It eliminates the need for expensive high-purity reagents, reducing raw material costs by over 30% compared to pure exogenous enzyme solutions. Furthermore, this invention replaces laccase and keratinase with in-situ production from the microbial strain. The entire preparation process is carried out at room temperature and pressure, requiring minimal equipment; a batch can be produced within 2.5 hours. This makes it suitable for on-site preparation and use in grassroots units such as farms and sanitation stations, significantly reducing transportation and storage costs and demonstrating substantial market competitiveness and industrialization potential. Detailed Implementation

[0022] The present invention will be further described below with reference to specific embodiments, but the scope of protection of the present invention is not limited to these embodiments. The strains used are from the following sources: All strains used in this invention are publicly available standard strains, and have been deposited at the China General Microbiological Culture Collection Center (CGMCC). The deposit information is as follows: White-rot fungus Phanerochaete chrysosporium: Accession number CGMCC 5.0776 Trametes versicolor: Collection number CGMCC 5.113 Bacillus licheniformis: Accession number CGMCC 1.804 Bacillus cereus: Accession number CGMCC 1.126 Saccharomyces cerevisiae (brewing yeast): Accession number CGMCC 2.399 Lactobacillus plantarum, photosynthetic bacteria, and actinomycetes were all selected from commercially available standard strains, which can be obtained from CGMCC or commercial strain libraries.

[0023] Note: All the strains mentioned above are publicly available strains that can be purchased directly by those skilled in the art without the need for isolation and screening.

[0024] Example 1: Preparation of the bacterial agent of the present invention According to the formulation range described in claim 6 of this invention, three different formulations of microbial agents were prepared. The specific composition of each formulation is shown in the table below: Table 1. Raw material composition of Example 1A1C compound microbial preparation

[0025] The fermentation broths of each strain were prepared separately: laccase-producing bacteria were inoculated into PDA medium and cultured at 28°C for 5 days, and the spore suspension was collected; keratinase-producing bacteria, Bacillus cereus, and yeast were inoculated into LB medium and cultured at 37°C for 24 hours; a compound probiotic (lactic acid bacteria, photosynthetic bacteria, and actinomycetes) was inoculated into its respective optimized medium, and after culture, they were mixed at a viable count ratio of 2:1:1. The viable counts of each fermentation broth met the requirements: laccase-producing bacteria ≥1×10⁻⁶. 8 CFU / g, keratinase-producing bacteria ≥1×10 9 CFU / g, Bacillus cereus ≥2×10¹ 0 CFU / g, yeast ≥1×10¹ 0 CFU / g, total live bacteria count of compound probiotics ≥1×10 9 CFU / g.

[0026] Preparation steps (taking Example 1B as an example; the preparation methods for Examples 1A and 1C are the same). 1. Grind wheat bran, rice bran, and corn flour into 90 mesh, dry them to a moisture content of 10%, mix them with bovine bone peptone, brown sugar, and potassium dihydrogen phosphate, and stir for 18 minutes until uniform to obtain the matrix carrier.

[0027] 2. Mix the fermentation broths after culture according to the ratio, centrifuge at 4℃ and 8000–10000 r / min for 15–20 min, discard the supernatant and collect the bacterial cells; wash the bacterial cells twice with sterile physiological saline, centrifuge at 4℃ and 8000–10000 r / min for 10 min each time, discard the supernatant to obtain purified bacterial cells.

[0028] 3. Mix the collected bacterial cells with the substrate carrier and dry them at 40°C until the moisture content is 8% to obtain a compound microbial agent.

[0029] 4. Cellulase, neutral protease and xylanase were mixed in proportion (0.5:0.2:0.2 in Example 1A, 0.8:0.4:0.4 in Example 1B, and 1.2:0.6:0.6 in Example 1C) to obtain an exogenous complex enzyme preparation.

[0030] 5. Package the compound microbial inoculant and the exogenous compound enzyme preparation separately.

[0031] Example 2: Test on the degradation and deodorization effect of the microbial agent of the present invention on chicken manure Fresh chicken manure (65% moisture content) was used as the experimental material. After being mixed evenly, it was divided into the following 5 groups, with 3 replicates in each group and 50 kg of manure treated in each replicate: (1) Enzyme pre-degradation stage Mix the exogenous compound enzyme preparation with solid feces in a certain proportion, adjust the moisture content of the material to 50%~60%, control the temperature at 40~50℃ and the pH at 6.5~7.5, stir once every 30 minutes, and let it stand for enzymatic hydrolysis for 2~4 hours.

[0032] (2) Activation and inoculation stage Add all the compound microbial agents and activate them at 35-45℃ for 1-2 hours to preferentially activate Bacillus cereus and achieve step-by-step and orderly activation of the bacterial community.

[0033] (3) Composting fermentation stage After inoculation, the material is piled into strips and the temperature is controlled at 35-42℃ for 3-4 days for mesophilic degradation to ensure the activity of white rot fungi to degrade lignin. Then, the temperature is naturally raised to 55-65℃ for 3-4 days for high-temperature composting. When the temperature exceeds 65℃, the pile is turned over. The total fermentation cycle is 10-15 days. The pile is turned over once a day for the first 3 days, and then once every 2-3 days thereafter.

[0034] Table 2 Experimental Grouping and Treatment Methods

[0035] Fecal samples from all groups were placed under the same environmental conditions: temperature 25±2℃, humidity 60%, and the samples were turned regularly. Gas and samples were collected before and after treatment to detect relevant indicators. The test results for each group after 72 hours of treatment are as follows: Table 3. Degradation and deodorization effects of each group after 72 hours of treatment.

[0036] Results Analysis: The removal rates of ammonia and hydrogen sulfide, as well as the degradation rates of lignin, keratin, and cellulose, of the microbial agents in experimental groups A, B, and C were significantly higher than those in the commercially available control group. This demonstrates that laccase-producing bacteria and keratinase-producing bacteria played a crucial role. All three formulations exhibited excellent degradation and deodorization effects, and the effects remained stable as the dosage varied within the scope of the claims, proving the rationality of the scope defined by the claims of this invention.

[0037] Example 3: Comparison of temperature changes and start-up time during composting Each group was set up according to the method in Example 2. The temperature change of the compost pile was monitored during the composting process. The composting start-up time (time required to reach 50°C), the highest temperature, and the time of high temperature maintenance were recorded. The results are as follows: Table 4 Comparison of composting temperature and start-up time

[0038] Results analysis: The composting start-up time of experimental group B was only 22 hours, while that of experimental groups A and C was 26 hours and 20 hours, respectively, both significantly better than the commercially available control group (36 hours). Regarding the maximum temperature, experimental groups A, B, and C reached 62℃, 63℃, and 65℃, respectively, with high-temperature maintenance times of 5 days, 6 days, and 7 days, respectively. In contrast, the commercially available control group only reached a maximum temperature of 52℃, with a high-temperature maintenance time of only 3 days. The results indicate that within the formulation range defined in the claims of this invention, the microbial agent can achieve rapid start-up and efficient fermentation.

[0039] Example 4: Verification of nitrogen retention effect Each group was set up according to the method in Example 2. After composting, the total nitrogen content was determined by the Kjeldahl method, and the nitrogen loss rate was calculated. The results are as follows: Table 5 Comparison of nitrogen retention effects before and after fermentation

[0040] Results analysis: The nitrogen loss rates of experimental groups A, B, and C were 15.1%, 12.8%, and 11.2%, respectively, all significantly lower than those of the commercially available control group (22.5%) and the blank group (36.1%). This indicates that laccase secreted by laccase-producing bacteria catalyzes the addition reaction of phenols and ammonia to form a humic-nitrogen complex, which fixes ammonia nitrogen in the humic material, effectively reducing nitrogen loss and improving the fertilizer efficiency of compost products.

[0041] Example 5: Verification of Seed Germination Index Each group was set up according to the method in Example 2. After composting, cucumber seeds were used to conduct a germination test, and the seed germination index was calculated. Seed germination index (GI) determination method Weigh 10 g of composted product and add sterile water at a material-to-liquid ratio of 1:10 (w / v). Extract by shaking at 25°C for 1 h and filter to obtain the extract. Use cucumber seeds as indicator seeds, place 20 seeds in each dish, and add 5 mL of extract evenly. Use sterile water as a blank control. Repeat each group 3 times. Incubate in a constant temperature incubator at 25°C in the dark for 48 h, and count the seed germination rate and measure the root length.

[0042] Calculation formula: GI (%) = (germination rate of treatment group × average root length of treatment group) ÷ (germination rate of control group × average root length of control group) × 100% The results are as follows: Table 6. Results of Seed Toxicity and Maturity Tests for Decomposed Products

[0043] Results analysis: The seed germination indices of experimental groups A, B, and C were 72.5%, 85.3%, and 90.2%, respectively. Among them, experimental groups B and C both exceeded the requirement of ≥70% in the "Organic Fertilizer" standard (NY / T 525-2021), and experimental group A was also close to the standard. This indicates that the compost products treated with the microbial agent of this invention have high maturity, no plant toxicity, and can be used directly as organic fertilizer.

[0044] Example 6: Effect of different bacterial community ratios on efficacy To verify the optimal ratio range of each bacterial group, following the method of Example 1B, the matrix and enzyme components were kept constant, while the proportions of laccase-producing bacteria, keratinase-producing bacteria, Bacillus cereus, yeast, and compound probiotics in the bacterial agent components were varied to prepare bacterial agents with different ratios. The ammonia removal rate, lignin degradation rate, and keratin degradation rate were then tested according to the method of Example 2 over 72 hours. The results are as follows: Table 7. Comparison of functional effects under different strain ratios

[0045] Results analysis: When the mass ratio of laccase-producing bacteria: keratinase-producing bacteria: Bacillus cereus: yeast: compound probiotics was (1-2):(2-3):(2-3):(1.5-2):(1.5-2), all indicators reached their optimal levels. Ratios that were too low or too high led to decreased efficacy, indicating a synergistic effect among the bacterial groups, requiring a certain ratio range to fully realize their potential.

[0046] In summary, the present invention has fully demonstrated and verified the technical solution through Examples 1-6. Example 1 provides the specific composition and preparation method of three typical ratios within the formulation range defined in claim 6, proving that the formulation of the present invention is adjustable and that each component can achieve good preparation effect within the stated range. Examples 2-5 use chicken manure as the treatment object to systematically verify the excellent performance of the microbial agent of the present invention in terms of degradation and deodorization, composting initiation, nitrogen retention, and compost maturity. The results show that the microbial agent of the present invention is significantly better than commercially available products at each ratio, and the effect remains stable as the formulation dosage changes within the scope of the claims, proving the rationality of the scope defined by the claims of the present invention. Example 6 further verifies the synergistic effect between the functional microbial groups and determines the optimal microbial ratio range. The above examples fully demonstrate that the present invention, by adopting a mixed strategy of exogenous enzyme + enzyme-producing bacteria and a sequential synergistic process of enzyme first and bacteria later, can achieve multiple beneficial effects such as rapid composting initiation, deep degradation of recalcitrant substances, efficient deodorization, and nitrogen retention. This compound bacteria can be directly applied to crops with significant effects: the core functions are as follows: the core functions of direct application 1. Promotes root growth and seedling development: Bacillus, yeast, and compound probiotics colonize around the root system, secrete auxins and enzymes, promote root development, and enhance crop absorption capacity.

[0047] 2. Disease suppression and stress resistance: Beneficial bacteria compete for space, inhibiting soil-borne pathogens (such as root rot and damping-off), and improving the crop's resistance to drought, cold, and continuous cropping.

[0048] 3. Nutrient activation: Laccase, keratinase, and other enzymes decompose solidified organic matter, stubble, and insoluble nutrients in the soil, transforming them into forms that crops can absorb, essentially acting as a "bio-fertilizer processing plant".

[0049] 4. Continuous soil improvement: Rice bran, rice husk powder, and other carriers gradually decompose, increasing soil organic matter and improving soil structure. Long-term application yields more significant results. Furthermore, the raw materials are inexpensive and the preparation process is simple, making it a promising candidate for industrial application and worthy of widespread adoption.

[0050] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or basic characteristics. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0051] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A composite microbial preparation for the degradation of solid feces, characterized in that, include: (1) Compound microbial inoculant, comprising: Laccase-producing fungi are white-rot fungi ( Phanerochaete chrysosporium ) or Yunzhi ( Trametes versicolor ); Keratinase-producing bacteria, selected from Bacillus licheniformis ( Bacillus licheniformis ); Auxiliary degrading bacteria, including Bacillus cereus ( Bacillus cereus ) and yeast ( Saccharomyces cerevisiae ); Complex probiotics, including lactic acid bacteria, photosynthetic bacteria and actinomycetes; (2) Exogenous complex enzyme preparations, including: cellulase, neutral protease and xylanase; The laccase-producing bacteria and keratinase-producing bacteria produce laccase and keratinase in situ during the degradation of solid feces. The exogenous compound enzyme preparation plays a role in the early stage of composting, providing an effective carbon and nitrogen source for the rapid reproduction of microorganisms.

2. The compound microbial preparation according to claim 1, characterized in that, The ratio of live bacteria, lactic acid bacteria, photosynthetic bacteria, and actinomycetes in the compound probiotics is (1-3):1:(1-2).

3. The compound microbial preparation according to claim 1, characterized in that, The mass ratio of the compound microbial agent to the exogenous compound enzyme preparation is (10-15):(3-6).

4. The compound microbial preparation according to claim 1, characterized in that, The viable count of the laccase-producing bacteria is ≥1×10⁻⁶. 8 CFU / g, the viable count of the keratinase-producing bacteria is ≥1×10⁻⁶. 9 CFU / g, the viable count of the *Bacillus cereus* is ≥2×10¹ 0 CFU / g, the viable count of the yeast is ≥1×10¹ 0 CFU / g, the total viable count of the compound probiotics is ≥1×10⁻⁶. 9 CFU / g.

5. The compound microbial preparation according to any one of claims 3 and 4, characterized in that, Includes the following components in parts by weight: Matrix components: 55-75 parts wheat bran, 16.5-24.5 parts rice bran or rice husk powder, and 15-30 parts corn flour or starch; Nutritional composition: 1.5–2.5 parts bovine bone peptone, 2–4 parts brown sugar, 0.5–0.8 parts potassium dihydrogen phosphate; Microbial agent components: 1-3 parts laccase-producing bacteria, 2-5 parts keratinase-producing bacteria, 2-6 parts Bacillus cereus, 1.5-4.5 parts yeast, and 1.5-4.5 parts compound probiotics; Components of the exogenous complex enzyme preparation: 0.5-1.5 parts cellulase, 0.2-0.8 parts neutral protease, and 0.2-0.8 parts xylanase.

6. A method for preparing a compound microbial preparation as described in any one of claims 1-5, characterized in that, Includes the following steps: (1) Laccase-producing bacteria, keratinase-producing bacteria, Bacillus cereus, yeast, and compound probiotics were cultured in liquid fermentation until the number of live bacteria reached the required level. (2) Mix the cultured fermentation broth in proportion and collect the cells by centrifugation; (3) The matrix carrier raw material is crushed to 80-100 mesh, dried to a moisture content of ≤12%, and mixed evenly with bovine bone peptone, brown sugar and potassium dihydrogen phosphate to obtain the matrix carrier; (4) Mix the bacterial cells collected in step (2) with the substrate carrier in step (3) and dry them at a low temperature of 35-45℃ until the water content is ≤10% to obtain a composite microbial agent; (5) Mix cellulase, neutral protease and xylanase in a certain proportion to obtain an exogenous complex enzyme preparation; (6) Package the compound microbial inoculant and the exogenous compound enzyme preparation separately.

7. The preparation method according to claim 6, characterized in that, The low-temperature drying in step (4) is performed using fluidized bed drying or vacuum drying.

8. A method of applying the compound microbial preparation as described in any one of claims 1-5, characterized in that, Includes the following steps: (1) Enzyme pre-degradation stage: Mix exogenous compound enzyme preparation with solid feces at a mass ratio of 1:500-1:1000, adjust the moisture content to 50%-60%, control the temperature at 40-50℃, and let it stand for 2-4 hours for enzymatic hydrolysis. (2) Inoculation stage: Add compound microbial agent to the enzymatic hydrolysate at 0.3%-0.5% of the fecal mass. Add all the mixed compound microbial agent to the enzymatic hydrolysate and mix evenly. Utilize the differences in bacterial tolerance, first let it stand at 35-45℃ for 1-2 hours to activate Bacillus cereus to germinate and produce nutrients, thus creating a suitable microenvironment for the system. (3) Composting fermentation stage: The inoculated material is piled into a pile, and the pile temperature is controlled at 35-42℃ for 3-4 days for mesophilic degradation to ensure the growth of white rot fungi and lignin degradation. Then, the temperature is naturally raised to 55-65℃ for high-temperature fermentation for 3-4 days. When the temperature exceeds 65℃, the pile should be turned over in time to control the temperature to not exceed 65℃. The total fermentation time is 10-15 days. The pile should be turned over once a day for the first 3 days, and then once every 2-3 days thereafter.

9. The application method according to claim 8, characterized in that, In step (1), the pH is controlled at 6.5-7.5 during the enzymatic hydrolysis process, and the mixture is stirred once every 30 minutes; in step (2), the activation temperature is 35-40℃ and the activation time is 1 hour.

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