Microbial complex microbial inoculant, method for promoting rapid composting of organic fertilizer and application

Abstract

The present application relates to the technical field of fertilizer, in particular to a kind of microbial compound inoculant, method and application for promoting the fast maturation of organic fertilizer;The method of the present application comprises inoculating microbial compound inoculant formed by Brevundimonas AFB I, Alcaligenes faecalis AFB II and achromobacter AFB III to compost containing cow dung and corn straw, and carrying out fermentation under natural conditions, the effective bacteria number ratio of Brevundimonas AFB I, Alcaligenes faecalis AFB II and achromobacter AFB III in microbial compound inoculant is 1:1:1, and cow dung and straw are mixed according to dry weight 3:1;The microbial compound inoculant developed by the present application can significantly improve the degradation efficiency of organic waste, accelerate the composting process, shorten the composting period, and improve the stability and fertility of compost products, providing new technical support for the resource utilization of agricultural waste.

Description

Technical Field

[0001] This invention relates to the field of fertilizer technology, specifically to a microbial compound inoculant, a method for promoting the rapid decomposition of organic fertilizer, and its application. Background Technology

[0002] As a vast treasure trove of organic matter and nutrients, straw and livestock manure are rich in nutrients such as nitrogen, phosphorus, and potassium, and have abundant organic matter content. However, livestock manure also contains many pollutants, including toxic gases such as ammonia and hydrogen sulfide, as well as pathogenic microorganisms such as bacteria. These can cause serious air pollution and affect the health of livestock and humans. Therefore, studying the current status and development path of agricultural waste treatment is an important means to solve environmental problems and achieve sustainable development.

[0003] Composting is a common method for converting agricultural waste into organic fertilizer. It utilizes aerobic microorganisms (bacteria, actinomycetes, fungi, etc.) under suitable conditions of ventilation, oxygen supply, temperature, moisture content, pH, and C / N ratio to effectively promote the transformation of biodegradable organic matter into stable humus. However, traditional composting suffers from problems such as long fermentation cycles, slow organic matter degradation, low humification levels, and safety concerns regarding compost products, becoming key factors restricting the industrialization of composting. Furthermore, agricultural waste typically contains high levels of recalcitrant organic carbon components, such as lignin, hemicellulose, and cellulose. Due to their complex structure and physicochemical composition, these components are among the most stable organic compounds in compost, leading to a low fermentation rate and hindering humus formation. Summary of the Invention

[0004] In view of the shortcomings of the prior art, the present invention aims to provide a microbial compound inoculant, a method and application for promoting the rapid decomposition of organic fertilizer, so as to improve the composting fermentation rate.

[0005] To solve the above problems, the present invention adopts the following technical solution:

[0006] A microbial compound inoculant includes *A. shortwave monoclonalis* AFB Ⅰ, *Alcaligenes faecalis* AFB Ⅱ, and *Achromobacterium afferentum* AFB Ⅲ; wherein, *A. shortwave monoclonalis* AFB Ⅰ was deposited at the China General Microbiological Culture Collection Center (CGMCC) on January 14, 2025, with accession number CGMCC No. 33411; *Alcaligenes faecalis* AFB Ⅱ was deposited at the same center on January 14, 2025, with accession number CGMCC No. 33412; and *Achromobacterium afferentum* AFB Ⅲ was deposited at the same center on January 14, 2025, with accession number CGMCC No. 33413.

[0007] An accelerator for rapid composting of organic fertilizer, comprising the aforementioned microbial compound inoculant.

[0008] An organic fertilizer comprising the aforementioned accelerator.

[0009] A method for promoting the rapid decomposition of organic fertilizer includes inoculating the aforementioned microbial compound agent into compost containing cow dung and corn stalks, and fermenting it under natural conditions.

[0010] As one possible implementation method, the compost inoculated with the microbial compound agent is turned over every three days during the 30 days before inoculation, and every five days after inoculation.

[0011] As one possible implementation method, the preparation method of the microbial compound inoculant includes inoculating shortwave monocytogenes AFB Ⅰ, alkali-producing bacteria AFB Ⅱ, and achromobacterium AFB Ⅲ into conical flasks containing LB medium and culturing them on a shaker at room temperature for 48 hours at a shaking speed of 200 rpm / min; the LB liquid medium consists of 10 g peptone, 5 g yeast extract, 10 g NaCl, and distilled water to a final volume of 1000 mL; and sterilizing at 121°C for 20 min using high-temperature moist heat.

[0012] After incubation on a shaker, the colony count was measured to be 1.0 × 10⁻⁶. 8 CFU·mL -1 A fermentation tank culture medium was prepared using peptone as a substrate. After autoclaving, the bacterial solution was mixed at a ratio of 1:1:1 and then introduced into the fermentation tank for fermentation culture for 48 hours. The colony count was measured and found to be up to standard, thus obtaining a liquid microbial compound inoculant.

[0013] As one possible implementation method, the effective colony count ratio of Shortwave Monoclonal bacteria AFB I, Alcaligenes faecalis AFB II, and Achromobacterium AFB III in the microbial compound inoculant is 1:1:1.

[0014] As one possible implementation method, the compost preparation method includes cutting corn stalks into small pieces of 0.5-1 cm, naturally air-drying cow dung and corn stalks, mixing cow dung and stalks at a dry weight ratio of 3:1 (w / w), and adjusting the initial compost moisture content to 60-65% with distilled water.

[0015] As one possible implementation method, the amount of the microbial compound agent added is 5%.

[0016] As one possible implementation method, the fermentation time under natural conditions is no less than 30 days.

[0017] Application of microbial compound inoculants in promoting rapid decomposition of organic fertilizer.

[0018] As one possible implementation method, the microbial compound inoculant promotes the increase of compost fermentation temperature and prolongs the thermophilic stage of compost fermentation.

[0019] As one possible implementation method, the microbial compound inoculant reduces nitrogen loss in compost and increases the humic acid content and cellulose degradation rate of compost.

[0020] The beneficial effects of this invention are as follows: the microbial compound inoculant provided by this invention can significantly improve the degradation efficiency of organic waste, accelerate the composting process, shorten the composting cycle, and enhance the stability and fertility of compost products. It provides new technical support for the resource utilization of agricultural waste. By optimizing the composting process and the application of the inoculant, it can improve composting efficiency, accelerate the humification process, and promote the efficient production of organic fertilizers, thus providing effective technical support for realizing the resource utilization of agricultural waste. Attached Figure Description

[0021] Figure 1 This is a temperature change curve during aerobic composting of cow dung and corn stalks.

[0022] Figure 2 A graph showing the change in moisture content during aerobic composting of cow dung and corn stalks.

[0023] Figure 3 This is a graph showing the pH change during aerobic composting of cow dung and corn stalks.

[0024] Figure 4 This is a graph showing the change in total carbon content in aerobic composting of cow dung and corn stalks.

[0025] Figure 5 This is a graph showing the change in total nitrogen content in aerobic compost of cow dung and corn stalks.

[0026] Figure 6 The graph shows the change in the carbon-to-nitrogen ratio (C / N ratio) during aerobic composting of cow dung and corn stalks.

[0027] Figure 7 A bar chart showing the changes in humic acid content in aerobic compost of cow dung and corn stalks.

[0028] Figure 8 A bar chart showing the changes in cellulose content in aerobic compost of cow manure and corn stalks. Detailed Implementation

[0029] The present invention will be further described in detail below with reference to specific embodiments.

[0030] It should be noted that these embodiments are only used to illustrate the present invention and are not intended to limit the present invention. Simple improvements to the method under the premise of the present invention are all within the scope of protection claimed by the present invention.

[0031] Example 1

[0032] The microbial compound inoculant of the present invention includes shortwave monocytogenes AFB I, alkaloidobacterium fecalith AFB II, and achromobacterium AFB III.

[0033] Among them, shortwave monocytogenes AFB I ( Brevundimonas sp. It was deposited on January 14, 2025, at the China General Microbiological Culture Collection Center (CGMCC), located at No. 3, Courtyard 1, Beichen Road, Chaoyang District, Beijing, with accession number CGMCC No. 33411.

[0034] Fecal alkaloid bacteria AFB II ( Alcaligenes faecalis It was deposited on January 14, 2025, at the China General Microbiological Culture Collection Center (CGMCC), located at No. 3, Courtyard 1, Beichen Road, Chaoyang District, Beijing, with accession number CGMCC No. 33412.

[0035] Achromobacterium hydroxychloroquine AFB III ( Achromobacter sp. It was deposited on January 14, 2025, at the China General Microbiological Culture Collection Center (CGMCC), located at No. 3, Courtyard 1, Beichen Road, Chaoyang District, Beijing, with accession number CGMCC No. 33413.

[0036] Preparation of compound microbial agents

[0037] The degrading bacteria are three types of cellulose-degrading bacteria (AFB I, α-shortwave monocytogenes) screened and preserved from cow manure compost, corn stalk piles, and farmland humus soil. Brevundimonas sp. ), fecal alkaloid bacteria AFB II ( Alcaligenes faecalis Achromobacterium IL-13 (Achromobacterium IL-13) Achromobacter sp. A highly efficient lignin-cellulose degrading strain combination H3 (effective colony count ratio of shortwave monocytogenes AFB Ⅰ, alkaloidobacterium coliforme AFB Ⅱ, and achromobacterium aFB Ⅲ 1:1:1) was screened out, and there was no antagonistic effect among them.

[0038] Shortwave monocytogenes AFB I, Alcaligenes faecalis AFB II, and Achromobacterium AFB III were inoculated into Erlenmeyer flasks containing 500 mL of LB medium and incubated on a shaker at room temperature for 48 hours at 200 rpm / min. LB liquid medium consisted of 10 g peptone, 5 g yeast extract, 10 g NaCl, and distilled water to a final volume of 1000 mL; the medium was then sterilized at 121 °C for 20 min using a high-temperature moist heat method.

[0039] After incubation on a shaker, the colony count was measured to be 1.0 × 10⁻⁶. 8 CFU·mL -1A fermentation culture medium was prepared using peptone as a substrate. After autoclaving, the bacterial solution was mixed at a ratio of 1:1:1 and inoculated into the fermenter for fermentation for 48 hours. The colony count was then measured to determine whether it met the standard, and a liquid microbial compound inoculant was obtained.

[0040] Example 2

[0041] aerobic composting experiment with cow dung and corn stalks

[0042] The composting materials used were fresh cow manure and corn stalks. The corn stalks were cut into small pieces of 0.5-1 cm, and the fresh cow manure and corn stalks were naturally air-dried in an experimental greenhouse to remove excess surface moisture. The main physicochemical properties of the compost materials are shown in Table 1. Cow manure and straw were mixed at a ratio of 3:1 (w / w, dry weight) to achieve a carbon-to-nitrogen ratio of approximately 25. The initial compost moisture content was adjusted to 60-65% with distilled water.

[0043] Table 1 Basic Physicochemical Properties of Compost Materials

[0044]

[0045] Two treatments were set up (CK-control group, inoculum H3), with three replicates for each treatment. The initial weight of each pile was 200 kg, and the volume of each pile was approximately 1 m × 0.8 m × 1 m (length × width × height). The concentration of the functional microbial inoculum was 1.0 × 10⁻⁶. 8 CFU·mL -1 Inoculation was performed at a concentration of 5%. The control group was inoculated with an equal volume of deionized water.

[0046] At the start of composting, a plastic film was placed over the pile to ensure proper heating. Composting then proceeded under natural conditions. For the first 30 days, the pile was manually turned every 3 days to ensure adequate ventilation; after day 30, it was turned every 5 days. Temperatures of the top, middle, and bottom layers of the pile were measured daily at 8:00 AM and 4:00 PM, and the daily average temperature was used for further analysis, while the ambient temperature was monitored. Samples were taken on days 1, 3, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, and 60 of the composting process, at depths of 0.25m, 0.5m, and 0.75m from the top of the pile, respectively. Three sub-samples were collected from each layer using a five-point sampling method. All sub-samples were thoroughly mixed to form a composite sample for that period. The composite sample was stored at 4°C for the determination of physicochemical properties.

[0047] Example 3

[0048] Determination and analysis of physicochemical indicators

[0049] from Figure 1As can be seen, the temperature of each treatment group rose rapidly in the initial stage of composting (the first 5 days), especially the H3 compound microbial agent group, which showed a significantly faster temperature rise than the control group. This indicates that inoculation with microbial agents can accelerate the metabolism of the compost material and quickly enter the thermophilic stage (temperature exceeding 50℃). The addition of the compound microbial agent significantly increased the compost temperature (5-10℃) and prolonged the thermophilic stage (5-7 days). Meanwhile, the H3 treatment group maintained a high temperature close to 50℃ around day 20, which helped to more effectively kill pathogens, insect eggs, and weed seeds in the compost, and promoted the degradation of recalcitrant organic matter (such as lignin and cellulose).

[0050] See Figure 2 As composting progressed, the moisture content of all treatment groups showed a decreasing trend. This reduction in moisture is typically related to the rapid decomposition of organic matter by microorganisms. Due to the active metabolism of microorganisms, they quickly utilize the moisture in the compost, promoting the decomposition of organic matter. Simultaneously, the increased composting temperature accelerates moisture evaporation, leading to a gradual decrease in moisture content. In the H3 compound microbial agent group, the vigorous metabolism of microorganisms promoted the degradation of organic matter and accelerated water utilization efficiency, resulting in a 20% decrease in moisture content.

[0051] See Figure 3 In the initial stage of composting, the pH value of each treatment group rose rapidly, reaching approximately 8.2-8.5. This is likely due to the ammonia produced during the initial decomposition of organic matter, which raises the pH value of the composting environment. The H3 group showed a significantly higher pH than the control group. Subsequently, the pH value showed a significant downward trend, approaching 7.6-7.8. The H3 group experienced a significantly greater decrease than the control group. This is because during microbial metabolism, some organic matter decomposes to produce organic acids (such as acetic acid and lactic acid), which lower the pH of the compost. In the later stage of composting, the pH value rose again, reaching 8.0-8.3. This is likely due to the gradual decomposition of organic acids, with the remaining organic matter being degraded to produce alkaline substances such as ammonia or carbonates. As the organic acids are consumed, the increase in alkaline substances in the composting environment leads to a rebound in pH.

[0052] See Figure 4 Initially, the total carbon content was high, approaching 350 g / kg in all groups. As composting progressed, the total carbon content in all treatment groups gradually decreased, especially in the first 20 days, with a significant drop. The total carbon content in group H3 decreased to around 270 g / kg, significantly lower than the control group. Afterward, the carbon content stabilized with minimal fluctuations. This is likely because during composting, microorganisms decompose organic matter, consuming carbon as an energy source. The high temperature in the early stages of composting led to active microorganisms and rapid degradation of organic matter, releasing carbon dioxide and causing a rapid decrease in total carbon content. As composting progressed into the humus stage, the recalcitrant components in the organic matter began to dominate the degradation process, thus gradually slowing the rate of decrease in total carbon.

[0053] See Figure 5 Unlike total carbon, the initial total nitrogen content was low, approximately 15 g / kg in the control group and slightly higher in group H3. During composting, the total nitrogen content gradually increased, peaking around day 30-40, then fluctuating slightly before stabilizing between 20-23 g / kg. Nitrogen transformation during composting was primarily driven by microbial activity. With the decomposition of organic matter, some nitrogen may be converted to ammonium and nitrate nitrogen through nitrification and denitrification in the nitrogen cycle. Simultaneously, nitrogen fixation occurs in the composting system, leading to a continuous increase in total nitrogen content. Compared to the control group, the addition of the compound microbial agent significantly reduced nitrogen loss by approximately 4.54% and improved nitrogen fixation capacity.

[0054] See Figure 6 In the initial stage, the C / N ratios of all treatment groups were high. As composting progressed, the C / N ratio decreased significantly, especially rapidly in the first 30 days, before gradually stabilizing and eventually settling between 12 and 14. The decrease in the C / N ratio during composting mainly reflects the rapid consumption of carbon and the accumulation of nitrogen. In the initial stage of vigorous microbial activity, carbon, as an energy source, was preferentially consumed, leading to a rapid decrease in the C / N ratio. As carbon decreased, the relative nitrogen concentration increased, consistent with the upward trend in total nitrogen content. When composting reached its later stages, the C / N ratio tended to stabilize, indicating that organic matter degradation had entered a relatively stable phase, and the degradation activity of microorganisms slowed down. As shown in the figure, compared to the control group, inoculation with the compound microbial agent significantly accelerated the degradation of organic matter and reduced nitrogen loss.

[0055] See Figure 7 In the initial stage of composting, easily decomposable organic matter such as sugars and proteins is rapidly degraded by microorganisms, generating a large amount of fulvic acid. The H3 treatment group, due to the addition of microbial degrading bacteria, exhibited stronger initial microbial activity, resulting in faster fulvic acid production and a relatively lower humic acid content. During the thermophilic stage, the humic acid content began to rise significantly, reaching 8.68 g / kg in the H3 group, 1.34 g / kg higher than the control group. This increase in humic acid indicates an accelerated humification process, with complex organic matter such as cellulose and lignin gradually decomposing and generating more humic acid, further enhancing the stability of the compost. In the maturity stage, the humic acid content continued to increase, reaching 10.59 g / kg in the H3 group, significantly higher than the control group's 8.15 g / kg. This trend indicates that the addition of the compound microbial agent accelerated humus formation; the humic acid content in the H3 group was 2.44 g / kg higher than the control group, an increase of approximately 29.94%, significantly improving the maturity and stability of the compost product.

[0056] See Figure 8During the initial and thermophilic stages of composting, the cellulose content in the control group and the H3 compound microbial agent group showed little change, indicating that cellulose degradation was slow in the initial stage, microbial activity was just beginning, and complex organic matter had not yet been significantly decomposed. During the thermophilic stage, the cellulose degradation rate in the control group began to slow down, and the cellulose content decreased more slowly, while the cellulose degradation in the H3 group accelerated significantly. The addition of the H3 compound microbial agent accelerated microbial metabolic activity and promoted rapid cellulose degradation. In the mature stage, the cellulose content in both the control and H3 groups decreased further, but the degradation effect in the H3 group was more significant, with the cellulose content dropping to 35.83 mg / g, far lower than the 53.78 mg / g in the control group. Overall, the cellulose content in the H3 treatment group decreased from the initial 104.97 g / kg to 35.83 g / kg, with a degradation rate of approximately 66.2%, demonstrating a significant degradation effect. In contrast, the cellulose content in the control group decreased from 106.86 g / kg to 53.78 g / kg, with a degradation rate of approximately 49.7%, indicating a slower degradation rate. H3 compound microbial agent improved cellulose degradation efficiency by approximately 16.5%, accelerated the decomposition of organic matter, and promoted composting.

[0057] Compared with the control group, the H3 group warmed up faster, the thermophilic phase was prolonged by 5-7 days, nitrogen loss was reduced by 4.54%, humic acid content was increased by 29.94%, and cellulose degradation rate was increased by 16.5%. Regarding the physicochemical changes in compost, the changes in total carbon and total nitrogen content in the H3 group indicate that microbial activity promoted the degradation of organic matter and nitrogen transformation. Meanwhile, indicators such as pH and C / N ratio also showed a trend conducive to improving soil fertility.

[0058] In summary, the compound microbial agent developed in this invention can significantly improve the degradation efficiency of organic waste, accelerate the composting process, shorten the composting cycle, and enhance the stability and fertility of compost products. It provides new technical support for the resource utilization of agricultural waste. By optimizing the composting process and the application of the microbial agent, it can improve composting efficiency, accelerate the humification process, and promote the efficient production of organic fertilizers, thus providing effective technical support for realizing the resource utilization of agricultural waste.

[0059] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described with reference to preferred embodiments, those skilled in the art should understand that various changes in form and detail can be made without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A microbial compound inoculant, characterized in that, By shortwave monocytogenes AFB I ( Brevundimonas sp. ), fecal alkaloid bacteria AFB II ( Alcaligenes faecalis ) and Achromobacterium IFN-γ ( Achromobacter sp. The sample consists of: *A. shortwave monocytogenes* AFB Ⅰ, which was deposited on January 14, 2025, at the China General Microbiological Culture Collection Center (CGMCC) with accession number CGMCC No. 33411; *A. fecal algae-producing bacteria* AFB Ⅱ, which was deposited on January 14, 2025, at the China General Microbiological Culture Collection Center (CGMCC) with accession number CGMCC No. 33412; and *A. achromobacterium* AFB Ⅲ, which was deposited on January 14, 2025, at the China General Microbiological Culture Collection Center (CGMCC) with accession number CGMCC No. 33413.

2. A rapid composting accelerator for organic fertilizer, characterized in that, Includes the microbial compound inoculant as described in claim 1.

3. An organic fertilizer, characterized in that, Includes the promoter as described in claim 2.

4. A method for promoting the rapid decomposition of organic fertilizer, characterized in that, The microbial compound agent described in claim 1 is inoculated into compost containing cow dung and corn stalks, and fermented under natural conditions.

5. The method for promoting rapid decomposition of organic fertilizer according to claim 4, characterized in that, It also includes turning the compost inoculated with microbial compound agents every three days for 30 days before inoculation, and every five days after inoculation.

6. The method for promoting rapid decomposition of organic fertilizer according to claim 4, characterized in that, The preparation method of the microbial compound inoculant includes inoculating shortwave monocytogenes AFB Ⅰ, alkali-producing bacteria AFB Ⅱ, and achromobacterium AFB Ⅲ into conical flasks containing LB medium and culturing them on a shaker at room temperature for 48 hours at a shaking speed of 200 rpm / min; the LB liquid medium consists of 10 g peptone, 5 g yeast extract, 10 g NaCl, and distilled water to a final volume of 1000 mL; and sterilizing at 121℃ for 20 min. After incubation on a shaker, the colony count was measured to be 1.0 × 10⁻⁶. 8 CFU·mL −1 A fermentation tank culture medium was prepared using peptone as a substrate. After autoclaving, the bacterial solution was mixed at a ratio of 1:1:1 and then introduced into the fermentation tank for fermentation culture for 48 hours. The colony count was measured and found to be up to standard, thus obtaining a liquid microbial compound inoculant.

7. The method for promoting rapid decomposition of organic fertilizer according to claim 4, characterized in that, The method for preparing the compost includes cutting corn stalks into small pieces of 0.5-1 cm, air-drying cow dung and corn stalks naturally, mixing cow dung and stalks at a dry weight ratio of 3:1, and adjusting the initial compost moisture content to 60-65% with distilled water.

8. The application of the microbial compound inoculant as described in claim 1 in promoting the rapid decomposition of organic fertilizer.

9. The application according to claim 8, characterized in that, The microbial compound inoculant promotes the increase of compost fermentation temperature and prolongs the thermophilic stage of compost fermentation.

10. The application according to claim 8, characterized in that, The microbial compound agent reduces nitrogen loss in compost and increases the humic acid content and cellulose degradation rate of compost.

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