Micro-plastic degradation system

Abstract

The invention discloses a micro-plastic degradation system, and relates to the technical field of environmental biotechnology and water ecological restoration, and the micro-plastic degradation system comprises an identification module used for dynamically monitoring micro-plastic in a water body; the capturing module is used for capturing the micro-plastic recognized by the recognition module; the degradation module is used for degrading the micro-plastics captured by the capturing module through genetically engineered bacteria; and the recycling module is used for recycling resource substances generated in the micro-plastic degradation system. The micro-plastic degradation efficiency is effectively improved.

Description

Technical Field

[0001] The present application relates to the fields of environmental biotechnology and water ecological restoration technology, and particularly to a microplastic degradation system. Background Art

[0002] As an emerging pollutant, microplastics (with a particle size less than 5 mm) have various impacts on the environment and human health. In particular, microplastics in water environment can affect the stability of the ecosystem and even have an impact on human health. Currently, the treatment of microplastics mainly relies on physical interception or microbial degradation.

[0003] The physical interception method is mainly used to remove microplastics with a larger particle size, and has poor treatment effect on microplastics with a smaller particle size. The natural degradation period of microorganisms is long and the efficiency is low. Therefore, it is urgent to solve the problem of the overall low efficiency in the microplastic degradation process. Summary of the Invention

[0004] The main purpose of the present application is to provide a microplastic degradation system, which effectively improves the degradation efficiency of microplastics.

[0005] To achieve the above object, an embodiment of the present application provides a microplastic degradation system, including the following modules:

[0006] An identification module, configured to dynamically monitor microplastics in water;

[0007] A capture module, configured to capture the microplastics identified by the identification module;

[0008] A degradation module, configured to degrade the microplastics captured by the capture module through genetically engineered bacteria;

[0009] A recovery module, configured to recover the resource substances generated in the microplastic degradation system.

[0010] In one embodiment, the identification module includes:

[0011] A Raman spectroscopy sensor, configured to collect spectral data of the microplastics;

[0012] A parameter determination module, configured to determine characteristic parameters of the microplastics according to the spectral data.

[0013] In one embodiment, the Raman spectroscopy sensor collects the spectral data of the two bands through dual-band Raman spectroscopy;

[0014] And / or, the parameter determination module includes a YOLO model.

[0015] In one embodiment, the capture module includes:

[0016] Magnetic particles with surface-modified plastic affinity groups for capturing the microplastics under an external magnetic field;

[0017] and / or, a network structure.

[0018] In one embodiment, the network structure includes:

[0019] A hydrophobic filter;

[0020] and / or, a plant network structure, which is a three-dimensional network structure formed by a first plant.

[0021] In one embodiment, the magnetic field intensity of the external magnetic field is determined according to the characteristic parameters;

[0022] and / or, the dosage of the genetically engineered bacteria is determined according to the characteristic parameters.

[0023] In one embodiment, the genetically engineered bacteria include:

[0024] A signal response module for activating the degradation activity of the genetically engineered bacteria in response to an activation signal when the activation signal meets a preset activation condition;

[0025] The activation signal is generated by the genetically engineered bacteria and / or a second plant included in the degradation module.

[0026] In one embodiment, the genetically engineered bacteria include a vector, and the vector includes:

[0027] A magnetic vector for regulating the distribution of the genetically engineered bacteria under an external magnetic field;

[0028] and / or, a temperature-responsive vector for releasing the genetically engineered bacteria it encapsulates when the environmental temperature where the genetically engineered bacteria are located is greater than a preset temperature threshold.

[0029] In one embodiment, the resource substance includes at least one of genetically engineered bacteria, degradation products, and capture materials.

[0030] In one embodiment, the recovery module includes at least one of the following:

[0031] An electrochemical reaction module;

[0032] A conversion reaction module;

[0033] An adsorption recovery module;

[0034] A data feedback module for dynamically adjusting the working parameters of the electrochemical reaction module and / or the conversion reaction module.

[0035] The embodiment of the present application provides a microplastic degradation system. An identification module is provided in the microplastic degradation system, which can dynamically monitor microplastics in water bodies, improve the identification accuracy of microplastics in water bodies, and accurately capture the identified microplastics in combination with the capture module in the microplastic degradation system to avoid omission of microplastics in water bodies. Furthermore, through the degradation module, genetically engineered bacteria are introduced into the degradation process of microplastics, which can specifically degrade different types of microplastics and effectively improve the degradation efficiency of microplastics. In addition, the recycling module can recycle the resource substances in the whole system, realize the recycling of resources, and avoid the problem of possible secondary pollution. Description of the Drawings

[0036] Figure 1 It is a schematic framework of the microplastic degradation system related to the embodiment of the present application Figure 1 ;

[0037] Figure 2 It is a schematic framework of the microplastic degradation system related to the embodiment of the present application Figure 2 ;

[0038] Figure 3 It is a schematic diagram of the activation scenario of the genetically engineered bacteria related to the embodiment of the present application.

[0039] Description of the Reference Numerals:

[0040] 10. Identification module; 20. Capture module; 30. Degradation module; 40. Recycling module;

[0041] 11. Raman spectroscopy sensor; 12. Parameter determination module;

[0042] 100. Genetically engineered bacteria; 101. IsPETase;

[0043] 201. Quorum sensing receptor; 202. Quorum sensing signaling molecule;

[0044] 203. Second plant sensing receptor; 204. Second plant signaling molecule.

[0045] The realization, functional characteristics and advantages of the purpose of the present application will be further described with reference to the embodiments and the accompanying drawings. Detailed Embodiments

[0046] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below. Those not specified in the embodiments are carried out according to conventional conditions or conditions recommended by the manufacturer. Those reagents or instruments not specified by the manufacturer can all be obtained as conventional products through commercial purchase.

[0047] Hereinafter, embodiments of the microplastic degradation system of the present application will be specifically disclosed in detail with appropriate reference to the accompanying drawings. However, there may be cases where unnecessary details are omitted. For example, there are cases where details of well-known matters are omitted and repeated descriptions of actually identical structures are omitted. This is to prevent the following description from becoming unnecessarily lengthy and to facilitate the understanding of those skilled in the art. In addition, the accompanying drawings and the following description are provided for those skilled in the art to fully understand the present application and are not intended to limit the subject matter recited in the claims.

[0048] The "range" disclosed in the present application is defined in the form of a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundary of a particular range. The ranges defined in this way can include the end values or not include the end values, and can be combined arbitrarily, that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60-120 and 80-110 are listed for a specific parameter, ranges of 60-110 and 80-120 are also contemplated. In addition, if the minimum range values 1 and 2 are listed, and if the maximum range values 3, 4, and 5 are listed, the following ranges are all contemplated: 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5. In the present application, unless otherwise specified, the numerical range "a-b" represents an abbreviated representation of any real number combination between a and b, where a and b are both real numbers. For example, the numerical range "0-5" means that all real numbers between "0-5" are fully listed herein, and "0-5" is only an abbreviated representation of these numerical combinations. In addition, when it is stated that a certain parameter is an integer ≥2, it is equivalent to disclosing that the parameter is, for example, the integer 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0049] If there is no special instruction, all embodiments and optional embodiments of the present application can be combined with each other to form a new technical solution.

[0050] If there is no special instruction, all steps of the present application can be carried out sequentially or randomly, and preferably sequentially. For example, the method includes steps (a) and (b), which means that the method can include steps (a) and (b) carried out sequentially, or can also include steps (b) and (a) carried out sequentially. For example, it is mentioned that the method may further include step (c), which means that step (c) can be added to the method in any order. For example, the method can include steps (a), (b), and (c), or can also include steps (a), (c), and (b), or can also include steps (c), (a), and (b), etc.

[0051] To make the above objects, features, and advantages of the present application more apparent and understandable, the technical solutions of the present application will be further described below in conjunction with the accompanying drawings and embodiments. However, the present application is not limited to the listed embodiments, and should also include any other well-known changes within the scope of the rights required by the present application.

[0052] To better understand the technical solutions of the present application, the following will be described in detail in conjunction with the specification drawings and specific embodiments.

[0053] In conventional technologies, the treatment of microplastics mainly relies on physical interception, chemical treatment, microbial degradation, etc. Among them, physical methods (e.g., filtration, adsorption) can only collect larger-sized microplastics, cannot be completely degraded, and have relatively high treatment costs; chemical methods (e.g., oxidation, photocatalysis) may cause secondary pollution and have relatively high requirements for equipment and technology; biological methods (e.g., microbial degradation) are environmentally friendly, but the degradation efficiency of natural microorganisms is low and it is difficult to achieve precise regulation; while the technology of genetically engineered bacteria provides a new direction for microplastic treatment, but its application is still limited by problems such as poor environmental adaptability and difficult control of degradation products.

[0054] The present application proposes a microplastic degradation system, including an identification module, a capture module, a degradation module, and a recovery module. The identification module can identify the type of microplastics and monitor the parameters of microplastics in the water body in real time, and the obtained parameters can be used for the subsequent modules of the microplastic degradation system; the capture module can intercept different types of microplastics through adsorption, hydrophobic interaction, or physical means, enrich the microplastics in the water body and then degrade them; the degradation module uses genetically engineered bacteria to target the degradation of microplastics, improve the microplastic degradation efficiency and generate pollution-free products; the recovery module recovers the products obtained from microplastic degradation and other recyclable resource materials in the microplastic degradation system through different technologies, and after recovery, they are reused to achieve resource recycling.

[0055] In a feasible embodiment, referring to Figure 1 , Figure 1 is the structural framework diagram of the microplastic degradation system involved in the embodiment of the present application. The microplastic degradation system includes: an identification module 10, a capture module 20, a degradation module 30, and a recovery module 40.

[0056] The identification module 10 is used to dynamically monitor the microplastics in the water body and can also determine the characteristic parameters of the microplastics in the water body, such as the type of microplastics, particle size, concentration, etc.

[0057] Optionally, the particle size of the microplastics is <5 mm, and the microplastics include at least one of PET (Polyethylene Terephthalate), PE (Polyethylene), and PS (Polystyrene).

[0058] The capture module 20 is used to capture the microplastics identified by the identification module.

[0059] Optionally, the capture methods of the capture module 20 include adsorption, interception, etc. For example, different types of capture materials can be used for different types of microplastics, and the microplastics can be captured by targeted adsorption and / or physical interception.

[0060] The degradation module 30 is used to degrade the microplastics captured by the capture module by genetically engineered bacteria. Genetically engineered bacteria refer to bacteria in which foreign target genes are introduced into host cells through in vitro recombination by means of genetic engineering and stably inherited and expressed therein.

[0061] Optionally, in the embodiments of the present application, the foreign target gene can be a coding gene of enzymes such as hydrolase and oxidase of microplastics (for example, PET, PE). The host cell refers to a cell that carries the coding gene and enables its expression, and can be Escherichia coli, Pseudomonas putida, etc.

[0062] Optionally, the host cell is Pseudomonas putida.

[0063] The recovery module 40 is used to recover the resource substances generated in the microplastic degradation system. Resource substances refer to substances that can be recycled and converted into utilizable resources used or generated in the microplastic degradation system.

[0064] In this embodiment, the microplastic degradation system includes: an identification module 10, a capture module 20, a degradation module 30, and a recovery module 40. The identification module 10 can dynamically monitor the microplastics in the water body and identify their types, particle sizes, and concentrations in real time. This enables the system to accurately grasp the distribution of microplastics in the water body and provide accurate information for subsequent treatment; the capture module 20 uses different capture materials for different types of microplastics (for example, PET, PE, PS), improving the capture efficiency; the degradation module 30 can efficiently degrade microplastics (for example, PET, PE, PS) through the expression of foreign hydrolase and oxidase by genetically engineered bacteria, significantly shortening the degradation time. Specific genetically engineered bacteria (such as Pseudomonas putida) are designed for different microplastic types, improving the targeting and efficiency of degradation; the recovery module 40 converts the degradation products into utilizable resources, realizing the resource utilization of waste. It is also possible to recover the reusable substances input in the microplastic degradation system, reducing resource waste.

[0065] In a feasible embodiment, with reference to Figure 2 , Figure 2 which is the structural framework diagram of the recognition module involved in the embodiments of the present application. The recognition module 10 includes a Raman spectroscopy sensor 11 and a parameter determination module 12.

[0066] The Raman spectroscopy sensor 11 is used to collect spectral data of microplastics. When a laser irradiates a microplastic sample, photons collide inelastically with sample molecules, causing a change in photon energy and generating Raman scattered light. The Raman spectroscopy sensor obtains the molecular vibration information of microplastics by detecting the frequency and intensity of this scattered light, thereby generating a Raman spectrum and obtaining the spectral data of microplastics. The spectral data can be spectral channels, spectral peak sequences, etc. Different types of microplastics generate specific Raman spectral data, which is used to distinguish the types of microplastics in water.

[0067] The parameter determination module 12 is used to determine the characteristic parameters of the microplastics according to the spectral data. The characteristic parameters can be the type, particle size, concentration, etc. of the microplastics. The parameter determination module 12 realizes the quantitative and qualitative analysis of microplastics by analyzing spectral data such as spectral channels and spectral peak sequences, in combination with algorithms and databases.

[0068] In this embodiment, the Raman spectroscopy sensor 11 excites a microplastic sample with a laser to generate Raman spectral data (such as spectral channels, spectral peak sequences, etc.) characterizing molecular vibration information, corresponding to different types of microplastics, and accurately identifies the categories of microplastics. Further combined with the parameter determination module 12, the spectral data obtained by the Raman spectroscopy sensor 11 is analyzed through algorithms and models to obtain characteristic parameters such as the particle size and concentration of microplastics, further improving the recognition accuracy of microplastics in water.

[0069] In a feasible embodiment, the Raman spectroscopy sensor 11 collects the spectral data of the two bands through dual-band Raman spectroscopy. At the same time, two different bands of lasers are used to irradiate the microplastic sample, and lasers with different wavelengths can excite different molecular vibration modes in the sample, thereby generating complementary Raman spectral data. In Raman spectroscopy, the selection range of the excitation wavelength is relatively wide, usually covering the ultraviolet, visible light to the near-infrared region. Preferably, the wavelengths of the two bands are 785 nm and 1064 nm respectively.

[0070] Optionally, the Raman spectroscopy sensor 11 collects the dual-band Raman spectral data corresponding to 785 nm and 1064 nm. Among them, the Raman spectrum in the 785 nm band is used to detect microplastics with a particle size ≥ 1 μm with a resolution ≤ 4 cm -1 ; the 1064 nm band is used to penetrate water with a turbidity ≤ 200 NTU (Nephelometric Turbidity Unit, scattering turbidity unit).

[0071] The parameter determination module includes a YOLO model. The YOLO (You Only Look Once) model in this embodiment can be a trained improved YOLO-MP v3.0 network model, and the YOLO-MP v3.0 network model can be an existing network model for algorithm classification of spectral data.

[0072] Optionally, the structure of the improved YOLO-MP v3.0 network model includes: an input layer, a convolutional layer, an attention module, sequence feature extraction, and an output layer.

[0073] Optionally, the input layer in the improved YOLO-MP v3.0 network model is a dual-band spectral fusion input. Compared with the conventional single-band spectral input, the dual-band spectral fusion input can enhance the recognition ability of microplastic chemical groups (such as C-H, C=O bonds, etc.).

[0074] Optionally, the convolutional layer of the improved YOLO-MP v3.0 network model is changed from a standard 3×3 convolution to a depthwise separable convolution layer (3×3). Compared with the conventional standard 3×3 convolution layer, the depthwise separable convolution layer (3×3) includes two steps: depth convolution and pointwise convolution. Depth convolution only extracts spatial features and does not change the number of channels; pointwise convolution adjusts the channel dimension and fuses cross-channel features. It can reduce the number of parameters by 70%, improve the computing efficiency, and adapt to the real-time processing requirements of edge devices (such as river monitoring sensors).

[0075] Optionally, an improved CBAM (Convolutional Block Attention Module, attention mechanism module) module is added to the improved YOLO-MP v3.0 network model. Among them, compared with the conventional one without or using a basic SE module, the CBAM module is essentially a channel and space hybrid attention mechanism. Compared with using only one attention mechanism, CBAM integrates two mapping processes of channels and spaces, can retain more information, and at the same time assigns heavier weights to more significant large features, thus ensuring that the network can focus the correct attention on the main targets. In this embodiment, CBAM simultaneously focuses on key spectral channels (such as PET characteristic peaks, etc.) and spatial regions (such as the edges of microplastic fragments), improving the classification robustness under complex backgrounds.

[0076] Optionally, the improved YOLO-MP v3.0 network model uses bidirectional LSTM (Long Short-Term Memory). Compared with the conventional model without or with single-directional LSTM, the bidirectional LSTM enhances the model's ability to capture sequence information. The bidirectional LSTM consists of two independent LSTM layers. One processes the sequence in the forward order, and the other processes the sequence in the reverse order. These two LSTM layers enable the model to utilize both the past and future information of the sequence simultaneously. In this embodiment, bidirectional LSTM is used for sequence feature extraction to capture the front and back associations of the spectral peak sequence (such as the continuous C-H vibration peaks of PE), solving the problem of insufficient modeling of long-range dependencies by single-directional LSTM.

[0077] Optionally, the output layer of the improved YOLO-MP v3.0 network model adopts a dual-task output mode of Softmax classification and regression prediction for particle size. Compared with the conventional output layer using the Softmax classification mode, the output layer of the improved YOLO-MP v3.0 network model can solve classification and regression problems simultaneously, and is suitable for tasks that require simultaneous output of discrete categories and continuous values. In this embodiment, the output layer synchronously outputs the microplastic type (such as PET / PE / PS) and the particle size (such as 0.1 - 5 mm), meeting the analysis requirements of the microplastic type and particle size distribution in the governance scenario.

[0078] Optionally, the improved YOLO-MP v3.0 network model incorporates GAN (Generative Adversarial Network). GAN consists of two parts: a generator and a discriminator. The generator attempts to generate data similar to the real data distribution, while the discriminator endeavors to distinguish whether the input data is real or generated by the generator. Compared with the conventional algorithm framework, the generator and discriminator of GAN continuously improve their performance through adversarial training and generate very realistic data. In this embodiment, the Generative Adversarial Network (GAN) is used to simulate the water body interference scenario to generate more training data under the water body interference scenario, so as to expand the diversity of the training set and improve the generalization ability of the improved YOLO-MP v3.0 network model.

[0079] Optionally, a GAN is used to simulate the water body interference scenario. The generated data includes the algae fluorescence background and the occlusion of suspended sediment particles. Exemplarily, the simulated concentration of chlorophyll a is 0 - 50 μg / L, and the simulated particle size of suspended sediment is 0.5 - 10 μm. The data generated by the GAN is imported into the improved YOLO-MP v3.0 network model for training. The improved YOLO-MP v3.0 network model after training is used to analyze and process the dual-band Raman spectrum parameters collected by the Raman spectrum sensor 11. The type of microplastics (such as PET / PE / PS) and the particle size (such as 0.1 - 5 mm) are output as the characteristic parameters of microplastics in the water body.

[0080] In this embodiment, through the dual-band Raman spectrum, different molecular vibration modes can be excited, providing complementary spectral information, improving the recognition accuracy of different types of microplastics (such as PET / PE / PS), and enhancing the recognition accuracy in high-turbidity water bodies. The parameter determination module uses the improved YOLO-MP v3.0 network model to analyze and process the dual-band Raman spectrum data, accurately outputs the category and particle size of microplastics, and further uses GAN to simulate the water body interference scenario to enhance the adaptability of the model to the interference scenario and improve the recognition accuracy of the improved YOLO-MP v3.0 network model.

[0081] In a feasible embodiment, the capture module includes a magnetic material with a plastic affinity group on the surface, which is used to capture microplastics under an external magnetic field.

[0082] The magnetic material is a magnetic core with a plastic affinity group on the surface. The plastic affinity group can have specific interactions with microplastics. For example, it can be through van der Waals forces, hydrogen bonds, electrostatic interactions, etc., so that the magnetic material can adhere to the microplastics. When an external magnetic field is applied, the magnetic material attached to the microplastics will be affected by the magnetic field force and move in the direction of the magnetic field, thus realizing the capture and separation of microplastics.

[0083] Exemplarily, the surface imprinted layer of the magnetic core Fe3O4@SiO2 is a benzene ring-binding peptide (the sequence includes Gly-Phe-Tyr-Arg) or an alkane chain-affinity protein (derived from Alcanivorax borkumensis). A pH-responsive polymer PNIPAM (Poly(N-isopropylacrylamide)) is grafted onto the surface of the imprinted layer, endowing the magnetic material with pH responsiveness and temperature responsiveness. The LCST (Lower Critical Solution Temperature) of PNIPAM is 32 °C. That is, below 32 °C, PNIPAM grafted on the surface of the imprinted layer of Fe3O4@SiO2 is in an extended state, and the surface of the magnetic material has good hydrophilicity; above 32 °C, PNIPAM will shrink, and the hydrophilicity of the surface of the magnetic material decreases. By adjusting the temperature, reversible changes in the surface properties of the material can be achieved.

[0084] The magnetic field strength of the external magnetic field is adjustable. Exemplarily, the magnetic field strength can be 0.1 - 1.0 T. The magnetic material has magnetism and can move directionally under the action of an external magnetic field. The benzene ring-binding peptide contains a benzene ring structure, and as the imprinted layer of the magnetic material, it can specifically recognize and adsorb microplastics containing benzene rings; the modification of the alkane chain-affinity protein as the imprinted layer of the magnetic material can specifically recognize and bind alkane compounds. Under different pH and temperature conditions, the adsorption and desorption behaviors of the magnetic material towards microplastics can change, enabling the controllable separation and enrichment of microplastics.

[0085] In a feasible embodiment, the capture module includes a network structure.

[0086] The network structure generally has a large number of pores and channels, as well as a high specific surface area, providing more active sites for capturing microplastics. The pore size and distribution can be regulated, and pores of different sizes can selectively capture microplastics of different sizes. The network structure can form a relatively stable framework, enabling the capture module to maintain its structural integrity under different environmental conditions and ensuring the continuous effectiveness of the capture function.

[0087] In a feasible embodiment, the network structure includes a hydrophobic filter.

[0088] Exemplarily, the pore size of the polypropylene fiber mesh is 20 - 50 μm, and the surface of the polypropylene fiber mesh is coated with polydimethylsiloxane (contact angle > 150°), which is used to capture hydrophobic PE / PP microplastics. The polypropylene fiber mesh is formed by interweaving polypropylene fibers, forming a network structure with a certain pore structure, and the pore size is determined according to the particle size distribution of hydrophobic PE / PP microplastics. Polydimethylsiloxane is a silicone polymer with good hydrophobicity. A contact angle > 150° indicates that the polypropylene fiber mesh coated with polydimethylsiloxane has superhydrophobic properties, which can improve the capture efficiency. When the water body containing hydrophobic PE / PP microplastics passes through the fiber mesh, microplastic particles with a particle size larger than the pore size will be directly intercepted on the surface of the fiber mesh and cannot continue to flow through the pores. Further, there is a hydrophobic interaction between the polydimethylsiloxane coating and the hydrophobic PE / PP microplastics. The hydrophobic interaction makes the microplastics more likely to adsorb on the surface of the fiber mesh, further improving the capture effect. Even microplastics with a particle size smaller than the pore size can be adsorbed on the surface of the fiber mesh due to the hydrophobic interaction, thus achieving effective capture of microplastics.

[0089] In a feasible embodiment, the network structure includes a plant network structure, and the plant network structure is a three-dimensional network structure formed by a first plant.

[0090] Exemplarily, the first plant can be emergent plants (e.g., Phragmites australis), floating plants (e.g., Eichhornia crassipes), submerged plants (e.g., Ceratophyllum demersum), etc., to form a three-dimensional network structure. The stems, leaves, and roots of the first plant are intertwined with each other to form a multi-level and multi-dimensional plant network structure, which can capture microplastics in the water body. The plant network structure utilizes the natural growth characteristics of plants, without chemical reagents or artificial materials, causing no secondary pollution to the environment, and the plants can continuously grow and update, maintaining the function of the network structure for a long time.

[0091] In a feasible embodiment, the magnetic field intensity of the external magnetic field is determined according to characteristic parameters.

[0092] The microplastic degradation system adopts dynamic closed-loop control and adjusts the operating state according to the system feedback information. Exemplarily, the magnetic field strength B = 05 + 0.1·d 1.5 + 0.02·c is adjusted according to the microplastic concentration and particle size monitored in real time, where d is the microplastic particle size (μm) and c is the microplastic concentration mg / m 2 . When the microplastic concentration in the water body increases and / or the microplastic particle size increases, the magnetic field intensity of the external magnetic field can be automatically adjusted to increase; when the microplastic concentration in the water body decreases and / or the microplastic particle size decreases, the magnetic field intensity of the external magnetic field can be automatically adjusted to decrease. Considering the quantitative relationship between the microplastic characteristic parameters monitored in real time in the water body and the external magnetic field intensity, precise regulation of the microplastic degradation system is achieved.

[0093] In a feasible embodiment, the dosage of the genetically engineered bacteria is determined according to the characteristic parameters.

[0094] For example, the chemical structure and chemical bond information of each substance in the microplastic degradation system can be monitored in real time by FTIR (Fourier Transform Infrared Spectroscopy) technology. During the degradation process, the type and concentration of the microplastic degradation intermediates will change as the reaction proceeds, and FTIR can detect the changes in the microplastic degradation intermediates. The PID (Proportional-Integral-Derivative) control algorithm is used to automatically adjust the dosage of the genetically engineered bacteria based on the feedback of the monitored intermediate information. For example, the proportional coefficient, integral coefficient, and differential coefficient in the PID control parameters can be K, p =0.8, K i =0.2, K d =0.1, PID control parameters jointly determine the dosage response mode and adjustment strength of the genetically engineered bacteria in the microplastic degradation system. During the degradation process, by real-time monitoring of intermediate products and dynamically adjusting the dosage of the bacterial agent, the degradation process can be kept in the best state as much as possible, the degradation efficiency can be improved, and unnecessary waste of genetically engineered bacteria can be reduced.

[0095] In a feasible embodiment, the genetically engineered bacteria includes a signal response module for activating the degradation activity of the genetically engineered bacteria in response to the activation signal when the activation signal meets a preset activation condition.

[0096] Genetically engineered bacteria refer to fungi that use genetic engineering methods to introduce exogenous target genes into host cells through in vitro recombination, and make them stably inherited and expressed in them. In this application, the exogenous target genes are coding genes for enzymes such as hydrolases and oxidases of microplastics (such as PET / PE / PS). Host cells refer to cells that carry coding genes and express them, which can be Pseudomonas putida, etc.

[0097] Exemplarily, Pseudomonas putida is used as a host, and the coding genes of PET hydrolase and PE oxidase are introduced, for example, PET hydrolase is IsPETase (Ideonella sakaiensis PETase, leaf bacterium cutinase); PE oxidase can be AlkB (Alkane Hydroxylase, alkane hydroxylase). The coding genes of IsPETase and AlkB are used to construct genetically engineered bacteria, and the constructed genetically engineered bacteria can be used to degrade microplastics PET and microplastics PE, respectively.

[0098] The signal response module refers to the designed receptor on the genetically engineered bacteria, which is used to receive signal molecules in the microplastic degradation system. When the activation signal meets the preset activation conditions, the response module responds to the activation signal. The signal molecule binds to the receptor to activate the degradation activity of the genetically engineered bacteria, and the genetically engineered bacteria start the expression process. The expression products are used to degrade microplastics in water bodies.

[0099] Exemplarily, the genetically engineered bacteria is Pseudomonas putida. The coding genes of PETase (Polyethylene terephthalate hydrolase) and MHETase (Mono(2-hydroxyethyl) terephthalate hydrolase) are fused and transformed into Pseudomonas putida. IPTG (Isopropyl β-D-1-thiogalactopyranoside) - induced T7 promoter is used to induce Pseudomonas putida to express PETase and MHETase, and the induction concentration of the promoter can be 0.1 - 1 mM. When reed root exudates are detected and meet the preset activation conditions, the promoter induction starts the gene expression process to generate PETase and MHETase for degrading microplastics in water bodies. During the expression process of PETase and MHETase, PelB (Pectate lyase B signal sequence) serves as a leader peptide to guide the nascent peptide chain through the cell membrane into the periplasmic space or secrete it into the extracellular environment, where the extracellular enzyme secretion efficiency ≥ 85%.

[0100] Optionally, the genetically engineered bacteria are fermented and cultured in a medium, which can be TB medium. TB medium uses glycerol as a carbon source, and the C / N ratio in the medium is adjusted to 25:1. The genetically engineered bacteria are immobilized in a sodium alginate - activated carbon carrier and cultured with shaking under the environmental conditions of 30 °C and 200 rpm. The pore size of the sodium alginate - activated carbon carrier is 2 - 3 mm, and the porosity ≥ 80%. When cultured to the situation of OD 600 (Optical Density) = 0.6, 0.5 mM IPTG is added to the medium to induce Pseudomonas putida to express PETase and MHETase.

[0101] The activation signal is produced by the genetically engineered bacteria and / or the second plant included in the degradation module.

[0102] Optionally, the activation signal is produced by genetically engineered bacteria. A quorum sensing (QS) module is set on the genetically engineered bacteria. QS is a collection of an intercellular communication mechanism and its related functional components existing in microorganisms such as genetically engineered bacteria. Its basic principle is that genetically engineered bacteria can produce and secrete one or more signal molecules into the extracellular environment. As the population density of the genetically engineered bacteria increases, the concentration of these signal molecules in the environment will also increase accordingly. When the concentration of the signal molecules reaches a certain threshold, an activation signal is generated. The signal molecules bind to receptors inside or on the surface of the genetically engineered bacteria cells, thereby activating gene expression and further regulating the population behavior of the genetically engineered bacteria.

[0103] Exemplarily, the QS receptor on the genetically engineered bacteria is LuxR (Lux Regulator, LuxR transcriptional regulatory protein), the signal molecule is AHL (N-Acyl Homoserine Lactones), and the preset activation condition is that the population density of the genetically engineered bacteria ≥ 10 6 CFU / mL (Colony Forming Unit). When the population density of the genetically engineered bacteria meets the preset activation condition, the signal molecule AHL binds to the receptor LuxR to form a LuxR-AHL complex. A binding site for LuxR is designed on the promoter. The LuxR-AHL complex activates the promoter to initiate the expression of downstream genes, generating IsPETase for degrading microplastics in water. When the population density of the genetically engineered bacteria in water reaches a certain threshold, the quorum sensing mechanism will initiate the expression of the enzyme for degrading microplastics, avoiding waste of resources and improving the degradation efficiency.

[0104] Optionally, the activation signal is produced by a second plant. The root exudates of the second plant can be substances such as sinapate esters, flavonoids (such as quercetin), organic acids (such as oxalic acid, citric acid), etc. A receptor for the root exudates of the second plant is designed on the genetically engineered bacteria. When the target root exudates of the second plant are detected as the activation signal, the signal molecules bind to receptors inside or on the surface of the genetically engineered bacteria cells, thereby activating gene expression.

[0105] Optionally, the second plant can be the same plant as the first plant.

[0106] Exemplarily, the plant signal receptor is the SinR transcription factor (derived from plant pathogens), which can specifically bind to sinapate esters (K d≈5 μM), the root system of reed plants can secrete sinapate esters. When the sinapate esters secreted by plants are detected and meet the preset activation conditions, they bind to the receptor on the genetically engineered bacteria to form a SinR-sinapate ester complex. The promoter is designed with a binding site for SinR. The SinR-sinapate ester complex activates the promoter to initiate the expression of downstream genes, generating IsPETase to degrade microplastics in water. The second plant root exudates, as natural signal molecules, precisely trigger the degradation function of genetically engineered bacteria, achieving the spatio-temporal matching of plant signal-guided microbial degradation and improving the efficiency of microplastic degradation in water.

[0107] In a feasible embodiment, refer to Figure 3 , Figure 3 This is a schematic diagram of the dual-signal-activated genetically engineered bacteria involved in the microplastic degradation system of this application. Genetically engineered bacteria 100, IsPETase 101, quorum-sensing receptor 201, quorum-sensing signal molecule 202, second plant-sensing receptor 203, and second plant signal molecule 204.

[0108] Receptors are designed on the genetically engineered bacteria 100: the quorum-sensing receptor 201 is the LuxR protein, and the second plant-sensing receptor 203 is the modified SinR transcription factor. When the second plant signal molecule 204 (sinapate ester) binds to the second plant-sensing receptor 203 to form a SinR-sinapate ester complex, and at the same time, the quorum-sensing signal molecule 202 (AHL) binds to the quorum-sensing receptor 201 to form a LuxR-AHL complex. The hybrid promoter Plux-sin is designed with LuxR binding sites and SinR binding sites, which bind to the SinR-sinapate ester complex and the LuxR-AHL complex, initiating the expression of the microplastic-degrading enzyme IsPETase 101. The expression level of IsPETase 101 increases by 50 - 100 times under the dual signals. The signal peptide PelB guides IsPETase 101 to be secreted into the periplasmic space of the cell, where it can act on microplastics at close range.

[0109] In a feasible embodiment, the genetically engineered bacteria include a vector, and the vector includes a magnetic carrier for regulating the distribution of the genetically engineered bacteria under an external magnetic field.

[0110] Exemplarily, Fe3O4@SiO2 magnetic carriers are internally loaded with genetically engineered bacteria. The genetically engineered bacteria use Pseudomonas putida as the host and introduce the encoding genes of IsPETase and AlkB. Under the regulation of an external magnetic field, they target and move to the areas with high concentrations of microplastic PET and microplastic PE in water. Combining the genetically engineered bacteria with the magnetic carrier can achieve the regulation of the distribution of genetically engineered bacteria in water through the action of an external magnetic field, and the genetically engineered bacteria can target the microplastic enrichment areas to achieve local high-concentration microbial enrichment.

[0111] In a feasible embodiment, the genetically engineered bacteria include a vector, and the vector includes a temperature-responsive vector, which is used to release the encapsulated genetically engineered bacteria when the environmental temperature where the genetically engineered bacteria are located is greater than a preset temperature threshold. Exemplarily, genetically engineered bacteria are loaded inside PNIPAM thermosensitive hydrogel microspheres, and the preset temperature threshold is 28 °C; the degradation module built-in reactor has a pH / temperature regulation device, where the pH regulation range is 6-8 and the temperature regulation range is 25-35 °C; when the environmental temperature where the genetically engineered bacteria are located > 28 °C, the PNIPAM thermosensitive hydrogel microspheres release the bacterial agent, and among them, the survival rate of the genetically engineered bacteria after encapsulation and release is > 80%. By combining the genetically engineered bacteria with the temperature-responsive vector and through the temperature regulation device of the built-in reactor, after the genetically engineered bacteria move to the area with a high concentration of microplastics, the temperature is precisely controlled to trigger the release, ensuring that the genetically engineered bacteria play a role in the target area and avoiding the reduction of degradation efficiency caused by premature or late release.

[0112] In a feasible embodiment, the genetically engineered bacteria include a vector, and the vector includes a magnetic vector and a temperature-responsive vector. Exemplarily, the genetically engineered bacteria adopt the combination of PNIPAM thermosensitive hydrogel microspheres and Fe3O4@SiO2 magnetic vectors to respectively achieve targeting to the area with a high concentration of microplastics in the water body under the action of a magnetic field and then releasing the genetically engineered bacteria by regulating the temperature through the built-in reactor, which can realize the targeted movement and precise release of the genetically engineered bacteria. The genetically engineered bacteria are concentratedly released in the target area, forming a high concentration of genetically engineered bacteria locally and accelerating the degradation process of microplastics.

[0113] In a feasible embodiment, the resource materials include one or more of genetically engineered bacteria, degradation products, and capture materials.

[0114] Optionally, the genetically engineered bacteria are combined with the magnetic vector. After the microplastics are degraded, the genetically engineered bacteria can be recycled and reused under the action of an external magnetic field. Exemplarily, the recovery rate of the genetically engineered bacteria under the action of an external magnetic field is > 95%, and the number of repeated uses is ≥ 50 times. The recycling of the genetically engineered bacteria reduces the waste of the genetically engineered bacteria, reduces costs, avoids the residue of the genetically engineered bacteria in the environment, and reduces the ecological risk.

[0115] Optionally, the degradation products refer to the products generated during the degradation process of different types of microplastics. Exemplarily, the products can be ethylene glycol, terephthalic acid, hydrogen (H2), carbon monoxide (CO), etc. Converting microplastics into valuable chemicals realizes resource utilization and reduces environmental pollution.

[0116] Optionally, the capture material refers to the magnetic material used by the capture module to capture microplastics, which can be recycled under the action of an external magnetic field. Exemplarily, the magnetic material is Fe3O4@SiO2 with a phenyl ring-binding peptide or alkane chain-affinity protein on the surface of the magnetic core imprinting layer, and a pH-responsive polymer PNIPAM is grafted onto the surface of the imprinting layer. After ultrasonic treatment for 10 minutes in a citric acid buffer solution with pH = 2, the desorption rate of the magnetic material > 95%; the magnetic material is recovered by an external magnetic field under the condition of a magnetic field strength of 0.5T; the adsorption efficiency of the recovered magnetic material remains at 90% after being recycled 50 times. Under the action of an external magnetic field, the capture material efficiently captures and recycles microplastics, reduces the diffusion of magnetic materials in the water environment, enables the reuse of the capture material, and reduces costs.

[0117] In a feasible embodiment, the recovery module includes at least one of the following:

[0118] An electrochemical reaction module;

[0119] A conversion reaction module;

[0120] An adsorption and recovery module;

[0121] A data feedback module for dynamically adjusting the working parameters of the electrochemical reaction module and / or the conversion reaction module.

[0122] Optionally, the electrochemical reaction module is used to purify and recover products through electrochemical reactions. Exemplarily, a Ti / PbO2 anode and a stainless steel cathode are used to recover terephthalic acid produced during the degradation of microplastics, and the purity of the obtained terephthalic acid ≥ 99%.

[0123] Optionally, the working parameters of the electrochemical reaction module include current density and electrolyte. Among them, the current density is 10mA / cm 2 , the electrolyte is 0.1M Na2SO4 and 0.05M H2SO4, and the pH of the electrolyte is 3. The recovery rate of terephthalic acid recovered by the electrochemical reaction module ≥ 92%. The terephthalic acid after electrochemical purification and recovery can be directly used in the production of polyester, and the process does not require the use of toxic chemicals, reducing secondary pollution.

[0124] Optionally, the conversion reaction module is used to recover products through chemical reactions. Exemplarily, the PE degradation product is converted into syngas (for example, the H2 / CO ratio is 1:2) at 600°C. The syngas obtained by the conversion reaction module can be used in the production of other chemical products (such as methanol, ammonia, etc.), realizing the recycling of resources.

[0125] Optionally, the adsorption recovery module is used to recover products through adsorption. Exemplarily, activated carbon adsorbs and recovers the product ethylene glycol. The ethylene glycol, a microplastic degradation product recovered by the adsorption recovery module, can be used to produce industrial products such as polyester, realizing the recycling of resources.

[0126] Optionally, the data feedback module uploads the working parameters of the electrochemical reaction module and / or the conversion reaction module to the cloud management platform, optimizes the working parameters through intelligent algorithms, and makes dynamic adjustments to improve the product purity and reduce the system energy consumption.

[0127] In a feasible embodiment, the microplastic degradation system is applicable to water environments (such as river channels, wastewater, etc.). The microplastic degradation system adopts a detachable design and is adjusted according to the actual water environment. Exemplarily, the applicable river channel cross-section width of the microplastic degradation system is 5 - 50 m; the protection level of the core components of the microplastic degradation system is IP68 (Ingress Protection), and the working temperature range is -20°C to 50°C.

[0128] In a feasible embodiment, the microplastic degradation system is used to degrade microplastics in water. Exemplarily, in the lower reaches of a certain urban river channel, the PET microplastic concentration is 200 particles / m 3 , and the steps of degrading microplastics using the microplastic degradation system include: the identification module sets up Raman spectroscopy sensors, and the dual-band Raman spectroscopy data and parameter determination module monitors the PET concentration in the lower reaches of the river channel in real time; the capture module captures PET with magnetic materials under the action of an external magnetic field (0.5 T); the genetically engineered bacteria are constructed based on the encoding gene of FAST-PETase, and the successfully constructed genetically engineered bacteria are loaded on the carrier. The temperature of the built-in reactor is set at 30°C, and the carrier releases the genetically engineered bacteria to degrade the microplastic PET (48 h); the ethylene glycol, a degradation product of the microplastic PET, is adsorbed by activated carbon and then recycled. In this embodiment, the PET removal rate is 97%, the ethylene glycol recovery rate is 80%, and the magnetic particle recovery rate is 99%. The targeted and efficient degradation of microplastics is achieved, and the products can be recycled.

[0129] In a feasible embodiment, the microplastic degradation system is used to degrade microplastics in water. Exemplarily, at the discharge outlet of a cosmetics factory, the PE microbead concentration is 1500 particles / m 3, the steps of degrading microplastics using the microplastic degradation system include: determining the PE concentration in the downstream of the river channel in real time through the dual-band Raman spectroscopy data and parameter determination module; the capture module uses a hydrophobic filter (pore size 20 μm) to capture PE microplastics and backwashes every 4 hours; the genetically engineered bacteria are constructed based on the coding gene of AlkB, and the successfully constructed genetically engineered bacteria are loaded on the carrier. Set the temperature of the built-in reactor to rise to 28°C, and the carrier releases the genetically engineered bacteria to degrade the microplastic PE. During the degradation process, a lipopeptide surfactant (0.1%) is added to improve the hydrophilicity of PE, and it is easier for the genetically engineered bacteria to attach to the surface of PE for degradation. The PE degradation rate is 89%, the water transparency is increased by 40%, and the bacterial agent recovery rate is 90%.

[0130] The above are only the preferred embodiments of the present application, and do not limit the patent scope of the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the patent protection scope of the present application.

Claims

1. A microplastic degradation system, characterized in that, The microplastic degradation system includes: An identification module for dynamically monitoring microplastics in water bodies; A capture module for capturing the microplastics identified by the identification module; A degradation module for degrading the microplastics captured by the capture module through genetically engineered bacteria; A recovery module for recovering the resource substances generated in the microplastic degradation system.

2. The microplastic degradation system according to claim 1, wherein The identification module includes: A Raman spectroscopy sensor for collecting spectral data of the microplastics; A parameter determination module for determining characteristic parameters of the microplastics according to the spectral data.

3. The microplastic degradation system according to claim 2, wherein The Raman spectroscopy sensor collects the spectral data of the two bands through dual-band Raman spectroscopy; And / or, the parameter determination module includes a YOLO model.

4. The microplastic degradation system according to claim 2, characterized in that, The capture module includes: Magnetic particles with surface-modified plastic affinity groups for capturing the microplastics under an external magnetic field; And / or, a reticular structure.

5. The microplastic degradation system according to claim 4, characterized in that, The reticular structure includes: A hydrophobic filter; And / or, a plant reticular structure, which is a three-dimensional reticular structure formed by a first plant.

6. The microplastic degradation system according to claim 4, wherein, The magnetic field intensity of the external magnetic field is determined according to the characteristic parameters; And / or, the dosage of the genetically engineered bacteria is determined according to the characteristic parameters.

7. The microplastic degradation system according to claim 1, wherein The genetically engineered bacteria include a signal response module for activating the degradation activity of the genetically engineered bacteria in response to an activation signal when the activation signal meets a preset activation condition; The activation signal is generated by the genetically engineered bacteria and / or a second plant included in the degradation module.

8. The microplastic degradation system according to claim 1, characterized in that, The genetically engineered bacteria include a vector, and the vector includes: A magnetic vector for regulating the distribution of the genetically engineered bacteria under an external magnetic field; And / or, a temperature-responsive vector for releasing the genetically engineered bacteria encapsulated therein when the environmental temperature where the genetically engineered bacteria are located is greater than a preset temperature threshold.

9. The microplastic degradation system according to claim 1, wherein, The resource substances include at least one of genetically engineered bacteria, degradation products, and capture materials.

10. The microplastic degradation system according to claim 1, characterized in that, The recovery module includes at least one of the following: An electrochemical reaction module; A conversion reaction module; An adsorption recovery module; A data feedback module for dynamically adjusting the working parameters of the electrochemical reaction module and / or the conversion reaction module.

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