Method and device for producing acid by enriching acid-producing functional bacteria

Abstract

The invention belongs to the technical field of microbial carbon sequestration and emission reduction, and particularly relates to a method and a device for producing acid by enriching acid-producing functional bacteria. The invention provides a method for producing acid by enriching acid-producing functional bacteria, which comprises the following steps: introducing working gas into a closed anaerobic microorganism system until the pressure of the system reaches 0.03-0.08 MPa, enriching the acid-producing functional bacteria and producing acid at the same time, the closed anaerobic microorganism system comprises an inoculation bacterium source; the working gas comprises carbon dioxide and hydrogen. The invention provides a method for rapidly enriching microorganisms with a carbon emission reduction function from different bacterium sources, mass transfer of hydrogen in water can be greatly promoted by controlling pressure, the efficiency of the microorganisms for electrically synthesizing high-added-value chemicals by using carbon dioxide and hydrogen is further improved, and a microbial carbon emission reduction technology is assisted.

Description

Technical Field

[0001] The present invention belongs to the technical field of microbial carbon fixation and emission reduction, and specifically relates to a method and a device for enriching acid-producing functional bacteria to produce acid. Background Art

[0002] In the field of biotechnology, especially in large-scale applications such as microbial carbon reduction, microbial electrosynthesis, and microbial fermentation, the rapid enrichment and screening of acid-producing functional bacteria is a key link in improving production efficiency and reducing production costs. Acid-producing bacteria, such as lactic acid bacteria and acetic acid-producing functional bacteria, are widely used in many fields such as food processing, biopharmaceuticals, and environmental governance. However, traditional enrichment methods often rely on a single inoculum source, such as soil, wastewater, or specific fermentation products. This method is not only time-consuming, but also has limited enrichment efficiency and strain diversity, making it difficult to meet the needs of modern industrial production for high-acid-producing strains.

[0003] In the prior art, although specific culture media and optimized culture conditions have been used to enrich acid-producing bacteria, these methods usually require complex equipment and high operating costs, and in the strain screening process, they can often only be optimized for a specific type of acid-producing bacteria, and cannot effectively cover a variety of acid-producing functional bacteria. For example, the enrichment of lactic acid bacteria is often carried out in a low pH and high sugar environment, while the enrichment of certain acetic acid-producing bacteria requires high oxygen and low sugar conditions. This targeted culture condition limits the diversity and adaptability of the strain. In addition, the traditional enrichment method also has the problems of strain degradation and contamination by foreign bacteria, which affects the quality and stability of the final product. In terms of the screening of electrosynthetic acid-producing functional strains, researchers are looking for strains that can efficiently produce acetic acid under specific electrochemical conditions. For example, starting a microbial electrosynthesis system through heterotrophic pre-culture can shorten the startup cycle and is more conducive to the enrichment of anaerobic acetic acid-producing microorganisms at the cathode, thereby increasing the acetic acid production concentration, but the functional bacteria enriched under this method are limited, and it is easy to enrich other microorganisms that can grow heterotrophically and compete with acetic acid-producing functional bacteria. Therefore, developing a method that can quickly and efficiently enrich a variety of acid-producing functional bacteria from different inoculum sources is of great significance for promoting the advancement of microbial electrosynthesis technology and fermentation technology and improving the quality and production efficiency of biological products. Summary of the invention

[0004] The object of the present invention is to provide a method and device for enriching acid-producing functional bacteria for acid production. The method provided by the present invention can quickly enrich acid-producing functional bacteria with carbon emission reduction function from different bacterial sources.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] The present invention provides a method for enriching acid-producing functional bacteria to produce acid, comprising the following steps:

[0007] The working gas is introduced into the closed anaerobic microbial system until the pressure of the system reaches 0.03-0.08 MPa, so that the acid-producing functional bacteria are enriched and acid is produced at the same time;

[0008] The closed anaerobic microbial system includes an inoculated bacterial source;

[0009] The working gas includes carbon dioxide and hydrogen.

[0010] Preferably, the volume ratio of carbon dioxide to hydrogen in the working gas is 1:2-8.

[0011] Preferably, the inoculated bacterial source includes anaerobic sludge, lake sediment or fermented sludge.

[0012] The present invention also provides a device for enriching acid-producing functional bacteria to produce acid, comprising a pressure detector, a reaction device and a gas pumping device;

[0013] The pressure detector is connected to the reaction device via a pressurizing needle;

[0014] The gas pumping device comprises an air pump and a gas collecting bag which are connected in sequence, and the air pump is connected to the reaction device through a gas pumping needle.

[0015] Preferably, the parameters of the pressure detector include: model YB80A, shell material 304 stainless steel, dial diameter 40 to 120 mm, measurement range -100 to 100 MPa, ambient temperature -20 to 70°C;

[0016] The length of the pressurizing needle is 4 to 12 cm.

[0017] Preferably, a bolt is further provided between the pressure detector and the pressurizing needle;

[0018] The diameter of the bolt is 6-12 mm.

[0019] Preferably, the air pump and the pump needle as well as an air tube between the gas collection bag and the air pump are also included;

[0020] The length of the pump needle is 4 to 12 cm;

[0021] The length of the air tube between the air pump and the air pump needle is 50 to 150 cm, and the length of the air tube between the gas collection bag and the air pump is 50 to 150 cm; the diameter of the air tube is 2*4 to 4*6 mm.

[0022] Preferably, the volume of the gas collection bag is 0.5-1L; the gas collection bag is provided with a double valve, and the valve diameter is 5*7mm.

[0023] Preferably, the parameters of the air pump include: the electrode type is a DC brushed motor, the gas flow rate is ≥1000mL / min, the negative pressure range is ≥0.04MPa, the positive pressure range is ≥0.05MPa, the power is 5W, the rated voltage is 12V, and the applicable temperature is -10℃~55℃.

[0024] Preferably, the reaction device comprises an open glass bottle, the mouth of the open glass bottle is sealed with a silicone plug and a matching perforated cover; the diameter of the bottle mouth is 30 mm; the volume of the open glass bottle is 0.2 to 5 L;

[0025] The pressurizing needle and the air pumping needle are fixed on the silicone plug.

[0026] The present invention provides a method for enriching acid-producing functional bacteria to produce acid, comprising the following steps: introducing a working gas into a closed anaerobic microbial system until the pressure of the system reaches 0.03-0.08 MPa, enriching the acid-producing functional bacteria and producing acid at the same time; the closed anaerobic microbial system comprises an inoculated bacterial source; and the working gas comprises carbon dioxide and hydrogen.

[0027] The present invention provides a method for rapidly enriching microorganisms with carbon emission reduction functions from different bacterial sources. By controlling the pressure, the mass transfer of hydrogen in water can be greatly promoted, and the efficiency of microorganisms in utilizing carbon dioxide and hydrogen for electrosynthesis of high-value-added chemicals can be further improved, thus contributing to microbial carbon emission reduction technology.

[0028] The present invention uses carbon dioxide and hydrogen as working gases, wherein carbon dioxide is used as a carbon source and hydrogen is used as an electron donor source to maintain the growth of microorganisms with carbon emission reduction functions, while inhibiting the growth of other microorganisms; at the same time, the pressurized operation can effectively improve the mass transfer of hydrogen in the solution, so that the microorganisms can efficiently use hydrogen as an electron donor to reduce carbon dioxide to high-value compounds. The method provided by the present invention can quickly screen functional microorganisms from different bacterial sources.

[0029] The present invention also provides a device for enriching acid-producing functional bacteria to produce acid, comprising a pressure detector, a reaction device and an air pumping device; the pressure detector is connected to the reaction device through a pressurizing needle; the air pumping device comprises an air pump and a gas collecting bag which are connected in sequence, and the air pump is connected to the reaction device through the air pumping needle.

[0030] In the device provided by the present invention, each component has low material cost, long service life, simple use, and has the potential for application of a large number of carbon-enriching and carbon-reducing functional bacteria. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1The result schematic diagram of the device provided by the present invention, wherein 1-pressure detector, 2-bolt, 3-pressurization needle, 4-reaction device, 5-pump needle, 6-air tube, 7-air pump, 8-gas collection bag;

[0032] Figure 2 This is a schematic diagram of the structure of using the device to produce acid in the embodiment;

[0033] Figure 3 The schematic diagram of the principle of the method provided by the present invention. DETAILED DESCRIPTION

[0034] The present invention provides a method for enriching acid-producing functional bacteria to produce acid, comprising the following steps:

[0035] The working gas is introduced into the closed anaerobic microbial system until the pressure of the system reaches 0.03-0.08 MPa, so that the acid-producing functional bacteria are enriched and acid is produced at the same time;

[0036] The closed anaerobic microbial system includes an inoculated bacterial source;

[0037] The working gas includes carbon dioxide and hydrogen.

[0038] In the present invention, the pressure reached by the system is 0.03-0.08 MPa, specifically 0.03 MPa, 0.04 MPa, 0.05 MPa, 0.06 MPa, 0.07 MPa, 0.08 MPa.

[0039] In the present invention, the volume ratio of carbon dioxide to hydrogen in the working gas is preferably 1:2-8, specifically 1:1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8.

[0040] In the present invention, the inoculated bacteria source preferably includes anaerobic sludge, lake sediment or fermented sludge. The present invention has no particular limitation on the source of the inoculated bacteria source, and any source known to those skilled in the art can be used.

[0041] The present invention also provides a device for enriching acid-producing functional bacteria to produce acid, comprising a pressure detector, a reaction device and a gas pumping device;

[0042] The pressure detector is connected to the reaction device via a pressurizing needle;

[0043] The gas pumping device comprises an air pump and a gas collecting bag which are connected in sequence, and the air pump is connected to the reaction device through a gas pumping needle.

[0044] In the present invention, the parameters of the pressure detector preferably include: model YB80A, shell material 304 stainless steel, dial diameter 40-120 mm, measurement range -100-100 MPa, ambient temperature -20-70° C. In a specific embodiment, the dial diameter is 80 cm.

[0045] In the present invention, the length of the pressurizing needle is preferably 4 to 12 cm, more preferably 5 to 10 cm, and even more preferably 6 to 8 cm.

[0046] In the present invention, a bolt is preferably provided between the pressure detector and the pressurizing needle. In the present invention, the diameter of the bolt is preferably 6 to 12 mm, more preferably 7 to 10 mm, and even more preferably 8 to 9 mm.

[0047] In the present invention, the reaction device preferably includes an open glass bottle; the material of the open glass bottle is preferably high borosilicate peeling; the mouth of the open glass bottle is preferably sealed with a silicone plug and a matching perforated cover; the model of the silicone plug is preferably GL405; the model of the perforated cover is preferably GL405, the material is preferably PP, and the diameter is preferably 34mm. In the present invention, the diameter of the bottle mouth is preferably 30mm; the volume of the open glass bottle is preferably 0.2 to 5L. In the present invention, the pressurizing needle and the pumping needle are preferably fixed on the silicone plug.

[0048] In the present invention, the gas collection bag is preferably an aluminum foil gas collection bag. In the present invention, the volume of the gas collection bag is preferably 0.5 to 1 L; the gas collection bag is preferably provided with a double valve, and the valve diameter is preferably 5*7 mm (where the first number is the inner diameter and the second number is the outer diameter, i.e., the inner diameter is 5 mm and the outer diameter is 7 mm).

[0049] In the present invention, the length of the air pump needle is preferably 4 to 12 cm.

[0050] In the present invention, the air pump and the pump air needle and the gas collection bag and the air pump preferably also include an air tube; the length of the air tube between the air pump and the pump air needle is preferably 50 to 150 cm, and more preferably 100 cm; the length of the air tube between the gas collection bag and the air pump is preferably 50 to 150 cm, and more preferably 100 cm; the diameter of the air tube is preferably 2*4 to 4*6 mm (the first number is the inner diameter, and the second number is the outer diameter, taking 2*4 mm as an example, the inner diameter is 2 mm and the outer diameter is 4 mm).

[0051] In the present invention, the condition parameters of the air pump preferably include: the electrode type is a DC brushed motor, the gas flow rate is ≥1000mL / min, the negative pressure range is ≥0.04MPa, the positive pressure range is ≥0.05MPa, the power is 5W, the rated voltage is 12V, and the applicable temperature is -10℃~55℃.

[0052] The structural schematic diagram of the device provided by the present invention is as follows Figure 1 As shown, wherein, 1-pressure detector, 2-bolt, 3-pressurization needle, 4-reaction device, 5-gas pump needle, 6-air tube, 7-air pump, 8-gas collection bag.

[0053] The method provided by the present invention is described below in conjunction with the device, specifically as follows:

[0054] The inoculated bacterial source is placed in the reaction device, and the pressure detector, the reaction device and the gas pumping device are assembled. The working gas in the gas collection bag is introduced into the reaction device through the gas pumping needle. At the same time, the pressure detector measures the pressure change in the reaction device through the pressurizing needle. When the pressure detector reading reaches the set value, the air pump is turned off and the gas pumping is terminated, and acid-producing functional bacteria are enriched and acid is produced at the same time.

[0055] The principle schematic diagram of the method provided by the present invention is as follows Figure 3 As shown, in the anaerobic closed microbial system, the carbon emission reduction functional bacteria (specifically acetogenic bacteria) mainly use the electron forking hydrogenase in the body to use hydrogen as an electron donor and carbon dioxide as a carbon source, and convert carbon dioxide into acetic acid, an organic substance required for growth, through its own Wood-Ljungdahl pathway. The presence of the pressure detector and the gas pump device enhances the mass transfer of hydrogen, an electron donor, in the system, and the carbon emission reduction functional bacteria obtain more electron donors, and the carbon fixation efficiency will also increase accordingly. The substrate sources of carbon dioxide and hydrogen can quickly screen out carbon emission reduction functional bacteria from different microbial sources, greatly improving the efficiency of carbon emission reduction.

[0056] Unless otherwise specified, the materials and equipment used in the present invention are all commercially available products in the art.

[0057] The technical solutions in the present invention will be described clearly and completely below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0058] Example 1

[0059] use Figure 2 The device shown produces acid and detects the acetic acid production;

[0060] 70 mL of fermented sludge was placed in a 500 mL borosilicate glass bottle, and the pressure detector, reaction device and gas pumping device were assembled, wherein the dial diameter of the pressure detector was 80 mm, and the length of the pressurizing needle was 6 cm; the pressure detector and the pressurizing needle were connected by stainless steel bolts, and the diameter of the bolts was 9 mm; the length of the gas pumping needle was 6 cm; the length of the air pipe between the air pump and the gas pumping needle was 100 cm, and the length of the air pipe between the gas collection bag and the air pump was 100 cm; the diameter of the air pipe was 3*5 mm;

[0061] A mixture of carbon dioxide and hydrogen in a volume ratio of 1:4 in a gas collection bag is introduced into the reaction device through a pump needle; at the same time, a pressure detector measures the pressure change in the reaction device through a pressurizing needle, and when the pressure detector reading reaches 0.05MPa, the air pump is turned off, and the pumping is terminated, and acid-producing functional bacteria are enriched and acid is produced at the same time;

[0062] The test solution was collected once every 2 days to determine the acetic acid production in the closed anaerobic system, and a total of 15 times were collected. The acetic acid concentration in the test solution at different time points was analyzed by gas chromatography, and the test results are shown in Table 1;

[0063] Table 1 Acetic acid production using fermented sludge as inoculation source

[0064] Number of days Acetic acid production (mg / L) 0 0 2 100 4 150 6 200 8 300 10 400 12 500 14 600 16 800 18 1000 20 1020 22 1030 24 1040 26 1050 28 1060 30 1080

[0065] Example 2

[0066] Acetic acid was prepared in the same manner as in Example 1, wherein the fermentation sludge was replaced by lake sludge;

[0067] The test results obtained are shown in Table 2;

[0068] Table 2 Acetic acid production using lake sediment as inoculation source

[0069]

[0070]

[0071] Example 3

[0072] Acetic acid was prepared in the same manner as in Example 1, wherein the fermented sludge was replaced by anaerobic sludge; the test results obtained are shown in Table 3;

[0073] Table 3 Acetic acid production of the system using anaerobic sludge as inoculation source

[0074]

[0075]

[0076] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention, not all of the embodiments. Other embodiments can be obtained based on this embodiment without creativity, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A method for enriching acid-producing functional bacteria for acid production, characterized in that: The following steps are involved: The working gas is introduced into the closed anaerobic microbial system until the pressure of the system reaches 0.03-0.08 MPa, so that the acid-producing functional bacteria are enriched and acid is produced at the same time; The closed anaerobic microbial system includes an inoculated bacterial source; The working gas includes carbon dioxide and hydrogen.

2. The method according to claim 1, characterized in that The volume ratio of carbon dioxide to hydrogen in the working gas is 1:2-8.

3. The method according to claim 1, characterized in that The inoculated bacterial source includes anaerobic sludge, lake sediment or fermented sludge.

4. A device for enriching acid-producing functional bacteria to produce acid, characterized in that: It includes a pressure detector, a reaction device and a gas pumping device; The pressure detector is connected to the reaction device via a pressurizing needle; The gas pumping device comprises an air pump and a gas collecting bag which are connected in sequence, and the air pump is connected to the reaction device through a gas pumping needle.

5. The device according to claim 4, characterized in that The parameters of the pressure detector include: model YB80A, material 304 stainless steel shell, dial diameter 40 to 120 mm, measurement range -100 to 100 MPa, ambient temperature -20 to 70 °C; The length of the pressurizing needle is 4 to 12 cm.

6. The device according to claim 4, characterized in that A bolt is also provided between the pressure detector and the pressurizing needle; The diameter of the bolt is 6-12 mm.

7. The device according to claim 4, characterized in that The air pump and the pump needle as well as an air tube between the gas collection bag and the air pump; The length of the pump needle is 4 to 12 cm; The length of the air tube between the air pump and the air pump needle is 50 to 150 cm, and the length of the air tube between the gas collection bag and the air pump is 50 to 150 cm; the diameter of the air tube is 2*4 to 4*6 mm.

8. The device according to claim 4, characterized in that The volume of the gas collection bag is 0.5-1L; the gas collection bag is provided with double valves, and the valve diameter is 5*7mm.

9. The device according to claim 4, characterized in that The parameters of the air pump include: the electrode type is a DC brushed motor, the gas flow rate is ≥1000mL / min, the negative pressure range is ≥0.04MPa, the positive pressure range is ≥0.05MPa, the power is 5W, the rated voltage is 12V, and the applicable temperature is -10℃~55℃.

10. The device according to claim 4, characterized in that The reaction device comprises an open glass bottle, the mouth of the open glass bottle is sealed with a silicone plug and a matching perforated cover; the diameter of the bottle mouth is 30 mm; the volume of the open glass bottle is 0.2 to 5 L; The pressurizing needle and the air pumping needle are fixed on the silicone plug.

Images