Fermentation device based on multi-physics field cooperation and application thereof

Abstract

The invention provides a fermentation device based on multi-physical field coordination and application thereof. The fermentation device comprises a fermentation tank unit, an annular magnetic field generation unit, a pulsed electric field generation unit and a control unit. The stable and energy-free background magnetic field is provided through the permanent magnet array, the background magnetic field and the pulsed electric field form synergy, the metabolism efficiency of microorganisms is remarkably improved, the operation cost is low, the device structure is simple, the device can be flexibly deployed, and the device is suitable for large-scale deployment and transformation on an industrial fermentation tank needing long-term and stable operation; a static background magnetic field generated by the permanent magnet is highly stable, is not influenced by fluctuation of a power grid, and is mutually independent and non-interfering with the distribution of a pulse electric field, so that the reliability and repeatability of the process are ensured.

Description

Technical Field

[0001] This invention belongs to the field of industrial biotechnology and fermentation engineering technology, and relates to a fermentation device based on multi-physical field synergy and its application. Background Technology

[0002] Lactic acid, as an important platform compound, continues to see growing demand in the food, pharmaceutical, and biodegradable plastics (such as polylactic acid, PLA) industries. Microbial fermentation is the core pathway for lactic acid production, but traditional fermentation processes face three key bottlenecks: First, severe product inhibition effects, where lactic acid accumulation leads to a decrease in the pH of the fermentation broth, strongly inhibiting cell activity and limiting the final yield; second, low intracellular and extracellular mass transfer efficiency, where nutrient absorption and product excretion become rate-limiting steps; and third, poor process economics, as maintaining a neutral pH requires the addition of large amounts of neutralizing agents, increasing subsequent separation and purification costs and environmental burden.

[0003] To overcome these limitations, physical field enhancement technology has attracted attention due to its green and residue-free characteristics. Pulsed electric field technology can promote substance transport by regulating cell membrane permeability, but the single electric field effect has obvious limitations: the parameter window is narrow, too low a field strength is ineffective, and too high a field strength can cause cell damage; the mode of action is singular, making it difficult to achieve systematic regulation of metabolic networks; the energy consumption is high, and the effect is unstable.

[0004] Magnetic field enhancement technology is another research direction, but existing technologies have obvious shortcomings: most of them use electromagnetic coil schemes, which require continuous power supply and cooling systems, resulting in high operating costs and complex systems. Their thermal effects may affect the stability of the fermentation system, and it is difficult to achieve a uniform field distribution on an industrial scale. On the other hand, simple static magnetic field treatment has limited effects, and the increase in lactic acid production is difficult to meet industrial needs. More importantly, the combination of magnetic and electric fields in existing technologies is mostly a simple superposition, lacking in-depth research and targeted design on the synergistic effects between fields.

[0005] Furthermore, existing technologies have not yet solved the core problem of multiphysics integration: how to achieve efficient coordination and long-term stable operation of physical fields without significantly increasing system complexity and energy consumption. Therefore, there is an urgent need in this field for a new fermentation enhancement scheme that can balance efficient coordination, low energy consumption, and industrial feasibility. Summary of the Invention

[0006] In response to the shortcomings of existing technologies and practical needs, this invention provides a fermentation device and its application based on multi-physics field synergy, aiming to achieve efficient metabolic enhancement while also possessing the advantages of simple structure and energy saving.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides a fermentation device based on multi-physics field synergy, the fermentation device comprising a fermentation tank unit, a ring magnetic field generating unit, a pulse electric field generating unit, and a control unit;

[0009] The fermentation tank unit includes a fermentation tank; the annular magnetic field generating unit includes multiple permanent magnets arranged in an annular magnetic array around the fermentation tank; the pulse electric field generating unit includes electrodes and a pulse power supply, the electrodes being respectively disposed at the top and bottom of the fermentation tank, and the pulse power supply being connected to the electrodes; the control unit is connected to the pulse electric field generating unit.

[0010] In this invention, a fermentation device based on the synergy of a permanent magnet array and a pulsed electric field is designed. The permanent magnet array provides a stable, energy-free background magnetic field, which works in synergy with the pulsed electric field to achieve efficient metabolic enhancement while also having the advantages of simple structure and energy saving.

[0011] Optionally, the fermenter body is cylindrical.

[0012] Optionally, the permanent magnet includes a neodymium iron boron permanent magnet.

[0013] Optionally, the neodymium iron boron permanent magnet includes N35-N45 grade neodymium iron boron permanent magnets.

[0014] Optionally, the configuration of the electrode includes a parallel plate electrode.

[0015] Optionally, the electrode material includes platinum-plated titanium or corrosion-resistant stainless steel.

[0016] Optionally, the output parameters of the pulse power supply are: voltage 0-30 kV, pulse width 1 μs-10 ms, and frequency 0.1-1000 Hz.

[0017] Secondly, the present invention provides the application of the fermentation device based on multi-physics field synergy described in the first aspect in microbial fermentation.

[0018] Thirdly, the present invention provides a microbial fermentation method, the microbial fermentation method comprising:

[0019] Microorganisms are inoculated into the fermenter of the multi-physics field synergistic fermentation device described in the first aspect for cultivation. During the cultivation process, a magnetic field is applied in the fermenter using the annular magnetic field generating unit, and a pulsed electric field is applied through the pulsed electric field generating unit.

[0020] Optionally, the microorganism includes any one of lactic acid bacteria, Lactobacillus acidophilus, Bifidobacterium longum, or Bifidobacterium breve.

[0021] Optionally, the lactic acid bacteria include Lactobacillus plantarum.

[0022] Optionally, the strength of the magnetic field is 5~100 mT, for example, it can be 10, 20, 30, 40, 50, 60, 70, 80 or 90 mT.

[0023] Optionally, the parameter range of the pulsed electric field is:

[0024] Electric field strength: 0.5 ~ 2.5 kV / cm, for example, it can be 0.6, 0.7, 0.8, 1, 1.5, 2, 2.2 or 2.4 kV / cm, etc.;

[0025] Pulse width: 10 ~ 500 μs, for example, it can be 12, 15, 20, 30, 50, 100, 150, 200, 300, 400, 410, 450, 460, 470, 480 or 490 μs, etc.;

[0026] Pulse frequency: 0.1 ~ 100 Hz, for example, it can be 0.2, 0.3, 0.5, 1, 5, 10, 20, 30, 40, 50, 60, 70, 80, 90, 95 or 99 Hz, etc.;

[0027] Waveform: Square wave or exponentially decaying wave.

[0028] Optionally, the coordinated timing control mode of the magnetic field and the pulsed electric field includes any of the following.

[0029] Synchronization mode: In the presence of a magnetic field, pulsed electric fields are applied at fixed time intervals.

[0030] Sequential mode: After the bacteria have entered the late logarithmic growth phase or the product synthesis phase, a pulsed electric field is then applied above the magnetic field.

[0031] Compared with the prior art, the present invention has at least the following beneficial effects:

[0032] This invention designs a fermentation device based on the synergy of a permanent magnet array and a pulsed electric field. The permanent magnet array provides a stable, energy-free background magnetic field, which works in synergy with the pulsed electric field to significantly improve the metabolic efficiency of microorganisms. It also avoids the continuous power consumption and heat dissipation system required by using large Helmholtz coils, reducing operating costs and simplifying the device structure. The permanent magnet array is compact, heat-free, easy to maintain, and flexible in deployment, making it very suitable for large-scale deployment and modification of industrial fermenters that require long-term, stable operation. The static background magnetic field generated by the permanent magnet is highly stable and unaffected by power grid fluctuations. The distribution of the permanent magnet array and the pulsed electric field are theoretically analyzed and experimentally verified to be independent of each other and do not interfere with each other, ensuring the reliability and repeatability of the process. The entire enhancement process is based on physical fields and does not require the addition of chemical substances. The permanent magnet scheme itself does not consume electricity, making it green and environmentally friendly. Attached Figure Description

[0033] Figure 1 An oblique axis view of the magnetic field array arrangement of the fermentation apparatus of the present invention;

[0034] Figure 2 This is a top view of the magnetic field array arrangement of the fermentation apparatus of the present invention;

[0035] Among them, 1 is the fermentation tank and 2 is the permanent magnet. Detailed Implementation

[0036] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments. However, the following examples are merely simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention is determined by the claims.

[0037] Where specific techniques or conditions are not specified in the examples, they shall be performed in accordance with the techniques or conditions described in the literature in this field, or in accordance with the product instructions. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased from legitimate channels.

[0038] This invention develops a fermentation device based on the synergy of a permanent magnet array and a pulsed electric field. The device includes a fermenter unit, a ring magnetic field generating unit, a pulsed electric field generating unit, and a control unit.

[0039] The fermenter unit is used for microbial fermentation culture and includes a fermenter. Specifically, the fermenter can be a cylindrical tank. The fermenter may also include other accessories for realizing the fermentation culture process, such as detection (temperature, pH, DO, etc.) sensors, temperature control accessories, material conveying accessories, etc.

[0040] The annular magnetic field generating unit is used to generate a uniform and stable static background magnetic field inside the fermenter. It includes multiple permanent magnets, which are arranged around the fermenter in an annular magnet array.

[0041] Optionally, the permanent magnet may be a neodymium iron boron (NdFeB) magnet, which has high performance and a magnetic energy product of not less than 35 MGOe.

[0042] Optionally, the annular magnet array is configured to generate a magnetic field strength of 5 to 100 mT at the geometric center of the fermenter. In a typical embodiment, 18 N35-N45 grade neodymium iron boron permanent magnets with dimensions of 20×20×10 mm can be arranged around a 5 L fermenter to generate a magnetic field of approximately 20 mT at the center.

[0043] Alternatively, as an alternative to or supplement to the permanent magnet scheme, the annular magnetic field generating unit may also include one or more pairs of Helmholtz coils surrounding the fermenter.

[0044] The pulsed electric field generating unit is used to generate a directional pulsed electric field in the culture medium inside the fermenter, and includes electrodes and a pulsed power supply.

[0045] The electrodes are respectively disposed at the top and bottom of the fermenter, and the electrodes are insulated and sealed from the inside of the fermenter.

[0046] The pulse power supply is connected to the electrode and is used to provide a pulse electrical signal with specific parameters.

[0047] Optionally, the electrode configuration may be a parallel plate electrode.

[0048] Optionally, the electrode may be made of titanium plated with platinum or corrosion-resistant stainless steel.

[0049] The control unit is connected to the pulse electric field generating unit and is used to control the parameters of the pulse electric field and its timing.

[0050] Optionally, the control unit is an electrical pulse sterilization device built into the fermentation equipment, or an external electrical fast transient pulse group simulator.

[0051] This invention further develops a lactic acid bacteria fermentation method based on the above-mentioned fermentation apparatus, comprising:

[0052] Lactic acid bacteria are inoculated into the fermenter for fermentation and culture. During the culture process, a constant static background magnetic field is applied in the fermenter using the annular magnetic field generating unit, while a pulsed electric field is applied intermittently through the pulsed electric field generating unit. The static background magnetic field and the pulsed electric field work together to promote the metabolic activity of the lactic acid bacteria.

[0053] Optionally, the parameter range of the pulsed electric field is:

[0054] Electric field strength: 0.5 ~ 2.5 kV / cm;

[0055] Pulse width: 10 ~ 500 μs;

[0056] Pulse frequency: 0.1 ~ 100 Hz;

[0057] Waveform: Square wave or exponentially decaying wave.

[0058] Optionally, the coordinated timing control of the pulsed electric field and the static background magnetic field is one of the following modes:

[0059] Synchronization mode: A pulsed electric field is applied at fixed time intervals against the background magnetic field generated by the permanent magnet.

[0060] Sequential mode: After the bacteria enter the late logarithmic growth phase or the product synthesis phase, a pulsed electric field is applied above the background magnetic field.

[0061] In specific embodiments of the present invention, a 5 L fermenter and a 10 L fermenter are used as examples to verify the technical solution of the present invention. The concentrations of glucose and lactic acid in the fermentation broth are determined by HPLC analysis of the supernatant after centrifugation, and the viable bacteria in the fermentation broth are estimated by plate count method.

[0062] Example 1

[0063] This embodiment demonstrates multi-physical field enhanced lactic acid fermentation in a 5 L fermenter.

[0064] (1) Device configuration

[0065] Fermentation tank: Cylindrical glass fermentation tank, total volume 5 L, working volume 4 L, tank diameter approximately 16 cm, height approximately 25 cm.

[0066] The annular magnetic field generating unit employs a neodymium iron boron (NdFeB) permanent magnet array, using a total of 18 N40 grade NdFeB permanent magnets (size 20×20×10 mm, remanence Br≈1.3T), arranged in three layers (upper, middle, and lower) surrounding the fermenter (see schematic diagram of the magnetic field array arrangement). Figure 1 and Figure 2 As shown in the figure, six magnets are evenly spaced in each layer. All magnets are aligned in the same direction (N pole facing inwards). According to actual measurements with a teslameter, a stable static magnetic field of 20.5 ± 1.2 mT is generated at the center of the fermenter.

[0067] Pulse electric field generating unit: adopts a parallel plate electrode configuration, with the top and bottom electrodes being 14 cm diameter titanium-plated platinum circular plates, installed through high-voltage insulating seals, and the electrode spacing being 22 cm; Pulse power supply: connected to the electrodes, with output parameters ranging from 0-30 kV, pulse width from 1 μs to 10 ms, and frequency from 0.1-1000 Hz.

[0068] (2) Fermentation process

[0069] Bacterial strain: Lactobacillus acidophilus.

[0070] Culture medium: MRS medium.

[0071] Fermentation conditions: temperature 37℃, initial pH 6.5, stirring speed 100 rpm, culture for 72 h, with feeding once at 24 h and 48 h respectively.

[0072] Physical field parameters:

[0073] Magnetic field: applied throughout, with a center strength of 20.5 mT.

[0074] Pulsed electric field: The field was applied starting from the mid-logarithmic growth stage (6 h after fermentation). The parameters were: electric field strength 1.2 kV / cm, pulse width 100 μs, frequency 5 Hz, and waveform square wave. The treatment was repeated 30 minutes apart for a total of 8 times.

[0075] (3) Comparative experiment

[0076] Two control groups were set up:

[0077] Experimental group: permanent magnet magnetic field + pulsed electric field;

[0078] Control group 1: Only a permanent magnet magnetic field was applied, without a pulsed electric field;

[0079] Control group 2: Ordinary fermentation (without any physical field treatment).

[0080] Example 2

[0081] This embodiment demonstrates multi-physical field enhanced lactic acid fermentation in a 10 L fermenter.

[0082] 1. System Configuration

[0083] Fermentation tank: Cylindrical stainless steel fermentation tank, total volume 10 L, working volume 8 L, tank diameter approximately 20 cm, height approximately 32 cm.

[0084] The annular magnetic field generating unit employs a neodymium iron boron (NdFeB) permanent magnet array. Twenty-four N42-grade NdFeB permanent magnets (25×25×15mm, remanence Br≈1.32T) are used, arranged in three layers (upper, middle, and lower) surrounding the fermenter, with eight magnets in each layer. Actual measurements show that a stable static magnetic field of 22.3±1.5 mT is generated at the center of the fermenter.

[0085] Pulsed electric field generating unit: The parallel plate electrodes are titanium-plated platinum circular plates with a diameter of 18 cm and an electrode spacing of 28 cm. Pulsed power supply: Same as in Example 1.

[0086] (2) Fermentation process

[0087] bacterial strains and culture media: Same as in Example 1

[0088] Fermentation conditions: temperature 37℃, initial pH 6.5, stirring speed 120 rpm, culture for 72 h, with feeding once at 24 h and 48 h respectively.

[0089] Physical field parameters:

[0090] Magnetic field: applied throughout, with a center strength of 22.3 mT.

[0091] Pulsed electric field: Applied from the middle stage of logarithmic growth, with the following parameters: electric field strength 1.5 kV / cm, pulse width 150 μs, frequency 3 Hz, and waveform square wave. Treatments were performed for 40 minutes each, with a 40-minute interval, for a total of 6 applications.

[0092] (3) Comparative experiment

[0093] The setup is the same as in Implementation Example 1.

[0094] The lactic acid yield was measured after fermentation in Examples 1 and 2, and the results are shown in Table 1. This indicates that the fermentation device of the present invention can effectively increase the lactic acid yield.

[0095] Table 1

[0096]

[0097] In addition, the glucose conversion rate and the number of viable bacteria at the end of each fermentation process were further analyzed, and the results are shown in Table 2.

[0098] Table 2

[0099]

[0100] As shown in Table 2, during the process of achieving maximum lactic acid production using the fermentation device of the present invention, the glucose conversion rate of the 5 L fermenter increased from 55.8% to 81.0% in ordinary fermentation, and the glucose conversion rate of the 10 L fermenter increased from 55.1% to 79.8% in ordinary fermentation. At the end of fermentation, the number of viable bacteria was higher than that of the ordinary fermentation group, indicating that the physical field treatment effectively alleviated the toxic effect of product inhibition on the bacteria. That is, the fermentation device of the present invention can effectively promote lactic acid bacteria fermentation and improve lactic acid production, fermentation efficiency and substrate conversion rate.

[0101] In summary, this invention designs a fermentation device based on the synergy of a permanent magnet array and a pulsed electric field. The permanent magnet array provides a stable, energy-free background magnetic field, which works in synergy with the pulsed electric field to significantly improve the metabolic efficiency of lactic acid bacteria. It also avoids the continuous power consumption and heat dissipation system required by large Helmholtz coils, reducing operating costs, simplifying the device structure, and offering flexible deployment. It is suitable for large-scale deployment and modification on industrial fermenters requiring long-term, stable operation. The static background magnetic field generated by the permanent magnets is highly stable, unaffected by power grid fluctuations, and its distribution is theoretically analyzed and experimentally verified to be independent and non-interfering with the pulsed electric field, ensuring the reliability and repeatability of the process. The entire enhancement process is primarily based on physical fields, requiring no chemical additives, and the permanent magnet solution itself consumes no electricity, making it green and environmentally friendly.

[0102] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A fermentation device based on multi-physics field synergy, characterized in that, The fermentation device includes a fermenter unit, a ring magnetic field generating unit, a pulse electric field generating unit, and a control unit; The fermentation tank unit includes a fermentation tank; The annular magnetic field generating unit includes multiple permanent magnets, which are arranged in an annular magnet array around the fermenter; The pulsed electric field generating unit includes electrodes and a pulsed power supply. The electrodes are respectively disposed at the top and bottom of the fermenter, and the pulsed power supply is connected to the electrodes. The control unit is connected to the pulse electric field generating unit.

2. The fermentation device based on multi-physics field synergy according to claim 1, characterized in that, The fermenter body is cylindrical.

3. The fermentation device based on multi-physics field synergy according to claim 1 or 2, characterized in that, The permanent magnet includes a neodymium iron boron permanent magnet; Optionally, the neodymium iron boron permanent magnet includes N35-N45 grade neodymium iron boron permanent magnets.

4. The fermentation apparatus based on multi-physics field synergy according to any one of claims 1-3, characterized in that, The electrode configuration includes parallel plate electrodes; Optionally, the electrode material includes platinum-plated titanium or corrosion-resistant stainless steel.

5. The fermentation apparatus based on multi-physics field synergy according to any one of claims 1-4, characterized in that, The output parameters of the pulse power supply are: voltage 0-30 kV, pulse width 1 μs-10 ms, and frequency 0.1-1000 Hz.

6. The application of the multi-physics field synergistic fermentation device according to any one of claims 1-5 in microbial fermentation.

7. A microbial fermentation method, characterized in that, The microbial fermentation method includes: Microorganisms are inoculated into the fermenter of the multi-physics field synergistic fermentation device according to any one of claims 1-5 for cultivation. During the cultivation process, a magnetic field is applied in the fermenter using the annular magnetic field generating unit, and a pulsed electric field is applied between the pulsed electric field generating units.

8. The microbial fermentation method according to claim 7, characterized in that, The microorganisms include lactic acid bacteria; Optionally, the lactic acid bacteria include Lactobacillus plantarum.

9. The microbial fermentation method according to claim 7 or 8, characterized in that, The strength of the magnetic field is 5~100mT; Optionally, the parameter range of the pulsed electric field is: Electric field strength: 0.5 ~ 2.5 kV / cm; Pulse width: 10 ~ 500 μs; Pulse frequency: 0.1 ~ 100 Hz; Waveform: Square wave or exponentially decaying wave.

10. The microbial fermentation method according to any one of claims 7-9, characterized in that, The coordinated timing control mode of the magnetic field and the pulsed electric field includes any of the following: Synchronization mode: In the presence of a magnetic field, pulsed electric fields are applied at fixed time intervals; Sequential mode: After the bacteria have entered the late logarithmic growth phase or the product synthesis phase, a pulsed electric field is then applied above the magnetic field.

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