Screening method of dominant flora for efficiently treating rural biomass waste

Abstract

The invention discloses a method for screening dominant bacterial communities for efficiently treating rural biomass wastes. The method comprises the following steps: step 1, collecting rural organic matter wastes and rural local activated sludge rich in microorganisms; step 2, mixing the collected organic matter waste and activated sludge according to a plurality of different mass ratios to obtain mixtures A1, A2,...... An; according to the method, organic matter waste and activated sludge rich in microorganisms are collected in rural areas, the organic matter waste and the activated sludge are mixed according to different mass ratios, activated carbon with different mass percentages is added, a culture dish is used for packaging, and samples are cultured in different temperature environments; finally, dominant bacterial communities for treating the organic waste are screened out through microorganism high-throughput sequencing, the optimal temperature interval for efficiently treating the organic waste and the optimal adding proportion of the activated carbon are obtained, and the method plays a key role in achieving large-scale treatment of the rural biomass waste.

Description

Technical Field

[0001] The present invention relates to the technical field of rural organic waste treatment, and specifically to a method for screening dominant bacteria groups for efficient treatment of rural biomass waste. Background Art

[0002] Rural biomass waste refers to organic waste generated during agricultural production, processing, and daily life, mainly including crop straws, rice husks, edible mushroom substrates, offcuts, firewood, tree barks, peanut shells, livestock and poultry manure, etc. These wastes have the characteristics of renewability, sustainability, rich resources, and diverse utilization methods.

[0003] Using microorganisms to treat rural biomass waste is a utilization method that has received much attention in recent years. Microorganisms have strong decomposition capabilities and can convert organic substances in biomass waste into harmless or low-toxic substances, while producing bioproducts with economic value.

[0004] After retrieval, there are few reports on the research work of using microorganisms to treat rural biomass waste. The growth and reproduction of microorganisms require suitable environmental conditions, such as temperature, humidity, pH value, etc. The composition of biomass waste is complex and contains various harmful substances, such as heavy metals, antibiotics, etc., which may have a negative impact on the growth and metabolism of microorganisms.

[0005] Therefore, exploring methods for using microorganisms to treat rural biomass waste and screening dominant bacteria groups plays a key role in the large-scale treatment of rural biomass waste. Summary of the Invention

[0006] The purpose of the present invention is to provide a method for screening dominant bacteria groups for efficient treatment of rural biomass waste to solve the problems raised in the above background art.

[0007] To achieve the above purpose, the present invention provides the following technical solutions: A method for screening dominant bacteria groups for efficient treatment of rural biomass waste, comprising the following steps: Step 1: Collect organic waste in rural areas and active sludge rich in microorganisms in rural areas. Step 2: Mix the collected organic waste and active sludge in various different mass ratios to obtain mixtures A1, A2, A3... An. Step 3: Divide the mixture A1 into several equal groups, and add activated carbon with different mass ratios to each group of mixtures to obtain samples A11, A12, A13... samples A1n. Step 4: Set up several constant-temperature incubators, evenly divide samples A11, A12, A13... A1n into multiple culture dishes, and place the culture dishes in incubators at different temperatures for cultivation; Step 5: Repeat Step 3 and Step 4 for mixtures A2, A3... An; Step 6: Sample the samples in the incubator every 7 days. With 28 days as a cycle, screen out the dominant bacteria for treating organic waste through microbial high-throughput sequencing, and obtain the optimal temperature range for efficiently treating organic waste and the optimal addition ratio of activated carbon.

[0008] As a further scheme of the present invention: The organic matter waste in rural areas is one or a combination of crop straws, poultry and livestock manure, and domestic kitchen waste.

[0009] As a further scheme of the present invention: In Step 2, the mass ratios of organic matter waste to activated sludge in each group of mixtures are 100:1, 90:1, 80:1... 10:1 respectively.

[0010] As a further scheme of the present invention: In Step 3, the mass percentages of activated carbon in each sample are 0.10%, 0.11%, 0.12%, 0.13%... 1.00% respectively.

[0011] As a further scheme of the present invention: In Step 4, the temperatures of each incubator are set at an arithmetic difference of 5°C, specifically 10 - 40°C.

[0012] Compared with the prior art, the beneficial effects of the present invention are: By collecting local organic matter waste and activated sludge rich in microorganisms in rural areas, mixing the organic matter waste and activated sludge in different mass ratios, adding activated carbon with different mass percentages, encapsulating with culture dishes, and culturing the samples in different temperature environments, the present invention finally screens out the dominant bacteria for treating organic waste through microbial high-throughput sequencing, and obtains the optimal temperature range for efficiently treating organic waste and the optimal addition ratio of activated carbon, which plays a key role in realizing the large-scale treatment of rural biomass waste. Specific Embodiments

[0013] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0014] In an embodiment of the present invention, a method for screening dominant bacteria groups for efficient treatment of rural biomass waste includes the following steps: Step 1: Collect organic waste from rural areas and active sludge rich in microorganisms from local rural areas. Step 2: Mix the collected organic waste and active sludge in various different mass ratios to obtain mixtures A1, A2, A3... An. Step 3: Divide the mixture A1 into several equal groups, and add activated carbon with different mass ratios to each group of the mixture to obtain samples A11, A12, A13... A1n. Step 4: Set up several constant-temperature incubators, evenly distribute the samples A11, A12, A13... A1n into multiple culture dishes, and place the culture dishes in incubators at different temperatures for cultivation. Step 5: Repeat Step 3 and Step 4 for the mixtures A2, A3... An. Step 6: Sample the samples in the incubator every 7 days, with 28 days as a cycle. Screen out the dominant bacteria groups for treating organic waste through microbial high-throughput sequencing, and obtain the optimal temperature range for efficient treatment of organic waste and the optimal addition ratio of activated carbon.

[0015] In the above Step 6, the instrument used for microbial high-throughput sequencing is the IIumina second-generation high-throughput sequencer, and the specific screening method is as follows: 1. Sample preparation: Detect and process the extracted DNA or RNA to ensure the purity and integrity of the sample. This step is crucial because the quality of the sample directly affects the accuracy and reliability of subsequent sequencing. 2. Library construction: Fragment the processed nucleic acid. Usually, use ultrasonic waves to break the DNA into lengths suitable for sequencing (such as 200 - 300 bp). Repair the ends of the fragmented DNA, add an "A" tail for subsequent addition of adapter sequences. Add specific adapter sequences to both ends of the DNA fragment. These adapter sequences include sequencing primer binding sites, tag sequences (used to distinguish different samples), and specific adapter sequences. After completing adapter ligation, perform library quality control to ensure that the library concentration and fragment size meet the sequencing requirements. 3. Bridge amplification: Load the constructed library onto the Flowcell (flow cell). The Flowcell is the carrier for the sequencing reaction, and its inner surface is coated with oligonucleotide sequences complementary to the sequences at both ends of the library. Perform bridge PCR amplification on the Flowcell to form a large number of DNA clusters to increase the signal intensity during sequencing. 4. Sequencing Reaction: Fluorescently labeled nucleotides are added. These nucleotides are sequentially added to the DNA strand being synthesized during DNA synthesis. By laser excitation and detection of the fluorescence signal, DNA sequence information is obtained. The Illumina sequencer uses the method of sequencing while synthesizing, that is, the fluorescence signal is detected every time a nucleotide is added, thereby gradually constructing a complete DNA sequence; 5. Data Analysis: A large amount of obtained sequencing data is processed and interpreted, including removing low-quality data, aligning with the reference genome, etc. Through data analysis, different microbial communities in the sample can be identified, and the dominant microbial communities can be screened according to their abundances.

[0016] The organic waste in the rural area is one or a combination of crop straws, livestock and poultry manure, and domestic kitchen waste.

[0017] In the above step two, the mass ratios of the organic waste to the activated sludge in each group of mixtures are 100:1, 90:1, 80:1... 10:1 respectively.

[0018] In the above step three, the mass percentages of activated carbon in each sample are 0.10%, 0.11%, 0.12%, 0.13%... 1.00% respectively.

[0019] In the above step four, the temperatures of each incubator are set at an arithmetic difference of 5°C, specifically 10 - 40°C.

[0020] Through a series of experiments using the above embodiments, the results obtained by the present invention show that the optimal temperature range for the cultured dominant microbial communities is 20°C - 30°C, the addition amount of activated carbon to promote the growth of microorganisms is 0.12% - 0.15%, and the optimal mass mixing ratio of rural organic waste to activated sludge is between 90:1 and 60:1.

[0021] The activated sludge used in the present invention is collected from a local natural sludge pond and contains anaerobic bacteria and aerobic bacteria. As the saying goes, "the soil and water in a place nourish the people there", and microbial strains also have such characteristics. Local strains have particularly good effects on treating local organic waste, which also conforms to the result of the evolution of the time microbial community. The activated sludge is collected from a local natural sludge pond and is not a commercially available product. The activated sludge is cultured in the laboratory to explore suitable conditions for the dominant microbial community, and then, the types of microorganisms can be determined through DNA sequencing technology.

[0022] The general rural organic waste used in the present invention includes human and livestock feces, grass and crop straws, and other domestic wastes. It has the characteristics of rural waste. The rural wastes at home and abroad are essentially the same, except that the microbial populations of activated sludge are different due to climate differences. The method for screening dominant bacterial strains in the present invention has universality and generality, and the screened microbial flora has obvious environmental protection advantages and economic value.

[0023] The incubator used in the present invention belongs to the prior art and can be a closed instrument with fixed temperature, humidity, and light.

[0024] The essence of the "solid wastes such as rural crop straws, livestock feces, and domestic kitchen wastes" adopted in the present invention, that is, its nature is organic waste. General rural organic waste includes human and livestock feces, grass and crop straws, and other domestic wastes. The target object to be studied and treated in the present invention is the organic matter therein, which has nothing to do with the content of various components of the "solid wastes such as rural crop straws, livestock feces, and domestic kitchen wastes" / "rural organic waste". Therefore, the rural waste adopted in the present invention belongs to the existing well-known term and has no concept of specific ratio.

[0025] The experimental results of the present invention show that by selecting a suitable temperature field, using activated carbon as a high-efficiency microbial culture agent, selecting a suitable mass ratio of waste to activated sludge, the method of using microorganisms to treat the waste generated in rural production and life is an efficient and feasible method.

[0026] Although the present invention has been described in detail with reference to the foregoing embodiments, for those skilled in the art, they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for screening dominant bacterial flora for efficiently treating rural biomass waste, characterized by: The following steps are involved: Step 1: Collect organic waste from rural areas and local activated sludge rich in microorganisms; Step 2: Mixing the collected organic waste with activated sludge in various mass ratios to obtain mixtures A1, A2, A3, ..., An; Step 3: Divide the mixture A1 into several groups in equal amounts, and add activated carbon in different mass ratios into each group of the mixture to obtain sample A11, sample A12, sample A13, ... sample A1n; Step 4: Set up several constant temperature incubators, and evenly load sample A11, sample A12, sample A13, ... sample A1n into multiple culture dishes, and place the culture dishes in incubators at different temperatures for culture; Step 5: Repeat steps 3 and 4 for mixtures A2, A3, ...An; Step 6: Samples in the incubator are collected every 7 days, with a cycle of 28 days. The dominant bacterial flora for treating organic waste is screened out through microbial high-throughput sequencing, and the optimal temperature range for efficient treatment of organic waste and the optimal addition ratio of activated carbon are obtained.

2. The method for screening dominant bacterial flora for efficiently treating rural biomass waste according to claim 1, characterized in that: The rural organic waste is one or a combination of crop straw, poultry and livestock excrement and domestic kitchen waste.

3. The method for screening dominant bacterial flora for efficiently treating rural biomass waste according to claim 1, characterized in that: In the step 2, the mass ratios of organic waste to activated sludge in each group of mixtures are 100:1, 90:1, 80:1...10:1 respectively.

4. The method for screening a dominant bacterial community for efficiently treating rural biomass waste according to claim 1, characterized in that: In the step three, the mass percentages of activated carbon in each sample are 0.10%, 0.11%, 0.12%, 0.13%...1.00% respectively.

5. The method for screening dominant bacterial flora for efficiently treating rural biomass waste according to claim 1, characterized in that: In step 4, the temperature of each incubator is set at an equal interval of 5°C, specifically 10-40°C.