CN114262723B - Method for promoting efficient enzymatic degradation of PET (polyethylene terephthalate) by using ferroferric oxide nanoparticle-mediated sunlight - Google Patents
Method for promoting efficient enzymatic degradation of PET (polyethylene terephthalate) by using ferroferric oxide nanoparticle-mediated sunlight Download PDFInfo
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- 229920000139 polyethylene terephthalate Polymers 0.000 title claims abstract description 107
- 239000002105 nanoparticle Substances 0.000 title claims abstract description 67
- 230000007515 enzymatic degradation Effects 0.000 title claims abstract description 19
- 238000000034 method Methods 0.000 title claims abstract description 16
- 230000001404 mediated effect Effects 0.000 title claims abstract description 8
- 230000001737 promoting effect Effects 0.000 title claims abstract description 5
- SZVJSHCCFOBDDC-UHFFFAOYSA-N ferrosoferric oxide Chemical compound O=[Fe]O[Fe]O[Fe]=O SZVJSHCCFOBDDC-UHFFFAOYSA-N 0.000 title claims description 4
- 239000005020 polyethylene terephthalate Substances 0.000 title description 79
- -1 polyethylene terephthalate Polymers 0.000 title description 7
- 108090000790 Enzymes Proteins 0.000 claims abstract description 67
- 102000004190 Enzymes Human genes 0.000 claims abstract description 67
- 230000000593 degrading effect Effects 0.000 claims abstract description 50
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- 125000002924 primary amino group Chemical group [H]N([H])* 0.000 claims description 2
- 230000035484 reaction time Effects 0.000 claims description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 2
- KKEYFWRCBNTPAC-UHFFFAOYSA-N Terephthalic acid Chemical compound OC(=O)C1=CC=C(C(O)=O)C=C1 KKEYFWRCBNTPAC-UHFFFAOYSA-N 0.000 description 24
- BCBHDSLDGBIFIX-UHFFFAOYSA-N 4-[(2-hydroxyethoxy)carbonyl]benzoic acid Chemical compound OCCOC(=O)C1=CC=C(C(O)=O)C=C1 BCBHDSLDGBIFIX-UHFFFAOYSA-N 0.000 description 12
- 239000000047 product Substances 0.000 description 11
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- 108010093096 Immobilized Enzymes Proteins 0.000 description 6
- NQTADLQHYWFPDB-UHFFFAOYSA-N N-Hydroxysuccinimide Chemical compound ON1C(=O)CCC1=O NQTADLQHYWFPDB-UHFFFAOYSA-N 0.000 description 6
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Classifications
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/62—Plastics recycling; Rubber recycling
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- Enzymes And Modification Thereof (AREA)
- Separation, Recovery Or Treatment Of Waste Materials Containing Plastics (AREA)
Abstract
The invention relates to Fe 3 O 4 Nanoparticle-mediated method for promoting PET degrading enzyme to degrade PET efficiently by sunlight, and PET degrading enzyme and Fe 3 O 4 The nanoparticles are physically mixed, or PET degrading enzyme and Fe 3 O 4 Covalent cross-linking of the nanoparticles; obtaining a PET degrading enzyme system; immersing the PET film in the PET degrading enzyme system in the step (1), and then placing the reaction system under sunlight for enzymatic degradation of PET. Magnetic Fe with sunlight heat energy 3 O 4 The nanoparticle and the PET degrading enzyme DuraPETase are combined together to act in the PET degradation field. At an intensity of 1kW/m 2 The temperature of the PET degradation system was raised from room temperature (25 ℃) to 46℃under the simulated sunlight. The degradation capability of the PET degrading enzyme on PET at normal temperature is improved, so that the PET degrading enzyme is more suitable for industrial application.
Description
Technical Field
The invention belongs to the field of PET biodegradation, and in particular relates to ferroferric oxide (Fe 3 O 4 ) Nanoparticle-mediated sunlight promotes efficient enzymatic degradation of PET.
Background
Polyethylene terephthalate (polyethylene terephthalate, PET) polyester plastics have excellent physical and chemical properties such as durability, plasticity, lightness and nondegradability, and thus are widely used in the manufacture of disposable beverage bottles, packaging bags, clothing and carpets. Because the chemical property of the plastic is extremely stable and is not easy to degrade, a large amount of plastic waste exists in landfill sites and oceans at present, and serious damage is caused to the ecological environment. There are many studies currently devoted to achieving efficient degradation and recycling of plastic waste products, and several chemical degradation methods are commonly used, such as glycolysis, methanolysis, hydrolysis and ammonolysis, but these methods generally require higher temperatures and produce some other environmental pollutants. Compared with the biological degradation, the method has great application prospect as an environment-friendly method.
Currently scientists have discovered and engineered a number of enzymes with PET degrading capabilities, including leaf-branching composting cutinase (LCC), humicola Insolens Cutinase (HiC), and durable PET degrading enzymes (DuraPETase), among others. Studies have shown that the temperature of the catalytic system has a great influence on the activity of the enzyme, and the current studies have shown that for most PET degrading enzymes, the degradation activity of the PET degrading enzymes on the PET is extremely low at normal temperature (less than or equal to 25 ℃), and that the enzyme catalysis at higher temperature is beneficial to enhancing the activity of the PET degrading enzymes. And the enzymatic degradation of PET is carried out at a higher temperature, which is beneficial to efficiently solving the problem of plastic pollution.
Increasing the temperature of the PET enzyme degradation system using conventional heating means consumes a large amount of energy, which limits the practical application capabilities of the PET degrading enzyme. At present, the shortage of energy source is a problem to be solved urgently for human development, and the search for renewable energy sources is urgent for continuous development. Efficient collection of solar energy is a great challenge and worldwide goal faced by humans, and the energy problem can be effectively solved by obtaining thermal energy from solar energy. Fe (Fe) 3 O 4 The nanoparticles (Magnetic Nanoparticle, MNP) have excellent photo-thermal capabilities, enabling conversion of light energy into thermal energy, both under Near Infrared (NIR) and Solar light (Solar light) irradiation.
Therefore, the invention adopts Fe 3 O 4 As a photothermal material, a PET degrading enzyme DurapETase and Fe 3 O 4 The temperature of a PET degradation reaction system is increased by utilizing solar energy, so that the degradation capability of DuraPETase on PET is improved.
Disclosure of Invention
The invention aims to solve the problems of low activity of PET degrading enzyme and need of external energy supply in the prior art and develops a method for utilizing Fe 3 O 4 The nano particles capture solar heat energy, so that the temperature of a PET biodegradation system is increased, and the PET degradation capability of the enzyme is improved. The invention uses Fe 3 O 4 Physical mixing or immobilization of PET degrading enzyme, fe 3 O 4 The sunlight photo-thermal capability of the fluorescent dye is introduced into the field of enzyme degradation of PET, so that the degradation capability of PET degrading enzyme on PET at normal temperature is improved, and the fluorescent dye is more suitable for industrial application.
In order to achieve the above object, the technical scheme of the present invention is summarized as follows:
the invention develops a Fe 3 O 4 The nanoparticle-mediated method for promoting PET degrading enzyme to degrade PET efficiently by sunlight comprises the following steps:
(1) PET degrading enzyme and Fe 3 O 4 The nanoparticles are physically mixed, or PET degrading enzyme and Fe 3 O 4 Covalent cross-linking of the nanoparticles; obtaining a PET degrading enzyme system;
(2) Immersing the PET film in the PET degrading enzyme system in the step (1), and then placing the reaction system under sunlight for enzymatic degradation of PET.
The PET degrading enzyme comprises leaf branching compost cutinase (LCC), specific Humicola cutinase (HiC) or durable PET degrading enzyme (DuraPETase); durapETase is preferred.
Fe as described in the present invention 3 O 4 The mass ratio of the nano particles to the PET degrading enzyme for physical mixing is 2-100:1.
Fe as described in the present invention 3 O 4 The particle size of the nano particles is 5-100nm.
Fe as described in the present invention 3 O 4 The surface of the nanoparticle is provided with carboxyl or amino.
Fe as described in the present invention 3 O 4 Covalent crosslinking of nanoparticles and PET degrading enzymes by 1- (3-dimethylaminopropyl) -3-ethylcarbodiThe reaction of the imine hydrochloride (EDC) with the N-hydroxysuccinimide (NHS) is completed as follows:
1) Fe is added to 3 O 4 Dispersing the nano particles into MES buffer solution, adding EDC and NHS to activate carboxyl on the surface of the nano particles, carrying out constant-temperature concussion reaction, separating and recovering after the reaction is finished, and repeatedly cleaning the nano particles with deionized water;
2) To activated Fe 3 O 4 Adding the nano particles into PS buffer solution containing PET degrading enzyme, placing into a constant temperature air shaking table for shake reaction, separating and recovering after the reaction is finished to obtain the Fe-immobilized material 3 O 4 PET degrading enzyme on the nanoparticle.
EDC and magnetic Fe as described in step 1) above 3 O 4 The mass ratio of the nano particles is 0.5-2:1, and the NHS and the magnetic Fe are as follows 3 O 4 The mass ratio of the nano particles is 0.5-1.5:1.
The MES buffer described in step 1) above is: 50mM, pH5.5.
Fe as described in the above step 2) 3 O 4 The mass ratio of the nano particles to the PET degrading enzyme is 5-25:1, the temperature of the constant temperature shaking table is 3-10 ℃, the rotating speed is 50-150rpm, and the reaction time is 1-5h.
The PS buffer described in step 2) above is: 50mM, pH 7.5.
In summary, due to the adoption of the technical scheme, the beneficial effects of the invention are as follows:
(1) The invention uses Fe with sunlight heat energy 3 O 4 The physical mixing or covalent crosslinking of the nanoparticle and the DuraPETase can raise the temperature of a reaction system for degrading PET by DuraPETase under the condition of sunlight irradiation, so that the degradation capability of DuraPETase to PET is improved. The two materials contain Fe within 4h under the illumination condition 3 O 4 The DuraPETase reaction system of nanoparticles has PET degradation products up to 70.4. Mu.M (physical mixing, example 2) and 30.9. Mu.M (covalent crosslinking, example 5) respectively, without Fe 3 O 4 The nanoparticle DurapETase did not have any PET degradation products.
(2) The invention uses Fe with sunlight heat energy 3 O 4 The nanoparticle effectively improves the reaction temperature of the PET degradation system under the sunlight condition, so that the temperature of the PET degradation system is increased from 25 ℃ to 46 ℃, thereby avoiding the consumption of external energy.
Drawings
FIG. 1 results of gel electrophoresis detection (SDS-PAGE) of the PET degrading enzyme DuraPETase.
FIG. 2 synthetic Fe 3 O 4 Transmission electron microscopy of nanoparticles.
FIG. 3 Fe under illumination 3 O 4 Nanoparticle-mediated PET degradation by DuraPETase.
Detailed Description
The technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention, and it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which are derived by a person skilled in the art based on the embodiments provided herein, fall within the scope of the disclosure.
Example 1:
expression and purification of PET degrading enzyme DuraPETase and Fe 3 O 4 Preparation of nanoparticles:
expression and purification of PET degrading enzyme DuraPETase can be described in the literature (ACS Catalysis,2021,11,1340-1350), and the purified DuraPETase can be analyzed by SDS-PAGE to determine purity and the results are shown in FIG. 1. A clear protein band exists at 28kDa, the molecular weight of which is consistent with the theoretical molecular weight of DuraPETase, and the purity of the purified protein of interest is up to 99.9% by software analysis, which is suitable for subsequent investigation.
In addition, fe is synthesized by adopting a solvothermal mode 3 O 4 Nanoparticles, preparation schemes can be referred to in literature (nanoscales, 2013,5,2133-2141), synthetic Fe 3 O 4 The morphology of the nano particles is shown in a transmission electron microscope chart of figure 2, which shows that the synthesized Fe 3 O 4 The nanometer particles have good dispersibility and the particle diameter is between 5 and 20 nm.
Examples 2 to 4, fe synthesized in example 1 3 O 4 The nanoparticles and DuraPETase configure a physical mixed reaction system.
Example 2:
preparing Fe with concentration of 2mg/mL 3 O 4 Nanoparticle solution, durapETase solution with concentration of 90.4 μg/mL was prepared at the same time, and the DurapETase solution and DurapETase solution were physically mixed to obtain DurapETase solution with concentration of 45.2 μg/mL, fe 3 O 4 The nanoparticle concentration was 1 mg/mL.
Enzymatic degradation of PET in the above reaction system under sunlight:
PET was cut into 6mm diameter discs for plastic degradation experiments. At room temperature (25 ℃ C.), the PET film was immersed in 1mL of the degradation reaction system, and irradiated with light (1 kW/m) 2 ) And carrying out degradation reaction under the condition. A control group was also set up and degradation of PET was performed under light for 4 hours with 1mL of free DuraPETase (45.2. Mu.g/mL) having the same amount of enzyme. After 4h of reaction, the samples were deactivated and the supernatants were centrifuged and tested by HPLC to determine the total amount of product mono (2-hydroxyethyl) terephthalate (MHET) and terephthalic acid (TPA).
As a result, as shown in FIG. 3, under the light conditions, fe was contained 3 O 4 The temperature of the physical mixing reaction system of the nano particles can be increased from 25 ℃ to 46 ℃, and the product quantity reaches 70.4 mu M after 4 hours. Whereas the temperature of the free enzyme reaction system was only raised from 25℃to 29.5℃and no product was formed within 4 hours. This demonstrates that Fe 3 O 4 Physical mixing of the nanoparticles with DuraPETase helps to enhance enzymatic degradation of PET under daylight conditions.
Example 3:
preparing Fe with concentration of 2mg/mL 3 O 4 Nanoparticle solution, durapetase solution with concentration of 1mg/mL is prepared at the same time, and the Durapetase solution and Durapetase solution are physically mixed to obtain the Durapetase solution with concentration of 500 mug/mL and Fe 3 O 4 The nanoparticle concentration was 1 mg/mL.
Enzymatic degradation of PET in the above reaction system under sunlight:
PET was cut into 6mm diameter discs for plastic degradation experiments. Under the condition of room temperature (25 DEG C) Immersing PET film in 1mL of the degradation reaction system under light (1 kW/m) 2 ) And carrying out degradation reaction under the condition. A control group was also set and degradation of PET was performed under light for 4 hours with 1mL of free DuraPETase (500. Mu.g/mL) having the same amount of enzyme. After 4h of reaction, the samples were deactivated and the supernatants were centrifuged and tested by HPLC to determine the total amount of product mono (2-hydroxyethyl) terephthalate (MHET) and terephthalic acid (TPA).
Example 4:
preparing Fe with concentration of 2mg/mL 3 O 4 Nanoparticle solution, durapetase solution with concentration of 20 mug/mL is prepared at the same time, and the Durapetase solution and Durapetase solution are physically mixed to obtain the Durapetase solution with concentration of 10 mug/mL and Fe 3 O 4 The nanoparticle concentration was 1 mg/mL.
Enzymatic degradation of PET in the above reaction system under sunlight:
PET was cut into 6mm diameter discs for plastic degradation experiments. At room temperature (25 ℃ C.), the PET film was immersed in 1mL of the degradation reaction system, and irradiated with light (1 kW/m) 2 ) And carrying out degradation reaction under the condition. A control group was also set and degradation of PET was performed under light for 4 hours with 1mL of free DuraPETase (10. Mu.g/mL) having the same amount of enzyme. After 4h of reaction, the samples were deactivated and the supernatants were centrifuged and tested by HPLC to determine the total amount of product mono (2-hydroxyethyl) terephthalate (MHET) and terephthalic acid (TPA).
Examples 5 to 7, fe synthesized in example 1 3 O 4 The nanoparticle and DuraPETase configure a covalent crosslinking reaction system.
Example 5:
taking 4mg Fe 3 O 4 Dispersing 5mg EDC and 4mg NHS into 2mL MES (pH, 5.5) buffer, and reacting at 150rpm in an air shaker at 25deg.C for 40min to obtain Fe 3 O 4 Activation of surface carboxyl groups and then recovery of activated Fe by magnetic separation 3 O 4 Nanoparticles were dispersed in 2mL PB (50 mM, pH 7.5) buffer containing 0.1mg/mL DurapETase, then reacted at 4℃and 120rpm for 4h, then immobilized by centrifugation and magnetic columnThe concentration of protein in the supernatant of the reaction liquid before and after immobilization is measured by using a immobilized enzyme separation reaction system and using Bradford, and the conclusion can be drawn through the principle of conservation of materials that the enzyme load of the prepared immobilized DuraPETase is 45.2 mug/mg Fe 3 O 4 . The immobilized enzyme is then configured as Fe 3 O 4 The concentration of the nanoparticle was 1mg/mL, and the enzyme content was 45.2. Mu.g/mL.
Enzymatic degradation of PET in the above reaction system under sunlight:
PET was cut into 6mm diameter discs for plastic degradation experiments. At room temperature (25 ℃ C.), the PET film was immersed in 1mL of the degradation reaction system, and irradiated with light (1 kW/m) 2 ) And carrying out degradation reaction under the condition. A control group was also set up and degradation of PET was performed under light for 4 hours with 1mL of free DuraPETase (45.2. Mu.g/mL) having the same amount of enzyme. After 4h of reaction, the samples were deactivated and the supernatants were centrifuged and tested by HPLC to determine the total amount of product mono (2-hydroxyethyl) terephthalate (MHET) and terephthalic acid (TPA).
As a result, as shown in FIG. 3, under the light conditions, fe was contained 3 O 4 The temperature of the covalent crosslinking reaction system of the nanoparticles can be increased from 25 ℃ to 46 ℃ and the product quantity reaches 30.9 mu M after 4 hours. Whereas the temperature of the free enzyme reaction system was only raised from 25℃to 29.5℃and no product was formed within 4 hours. This demonstrates that Fe 3 O 4 Covalent cross-linking of the nanoparticles with DuraPETase helps to enhance enzymatic degradation of PET under daylight conditions.
Example 6:
first 4mg Fe is taken 3 O 4 8mg EDC and 6mg NHS were dispersed in 2mL MES (pH 5.5) buffer and reacted in an air shaker at 25℃at 150rpm for 40min to achieve Fe 3 O 4 Activation of surface carboxyl groups and then recovery of activated Fe by magnetic separation 3 O 4 Nanoparticles were dispersed in 2mL of PB (50 mM, pH 7.5) buffer containing 0.08mg/mL DurapETase, then reacted at 3℃and 50rpm for 5 hours, and then the immobilized enzyme was separated from the reaction system by centrifugation and magnetic column, and the immobilization was measured before and after using BradfordThe concentration of protein in the supernatant of the reaction solution can be concluded by the principle of conservation of material that the enzyme loading of the prepared immobilized DuraPETase is 24.3 mug/mg Fe 3 O 4 . The immobilized enzyme is then configured as Fe 3 O 4 The concentration of the nanoparticle was 1mg/mL, and the enzyme content was 24.3. Mu.g/mL.
Enzymatic degradation of PET in the above reaction system under sunlight:
PET was cut into 6mm diameter discs for plastic degradation experiments. At room temperature (25 ℃ C.), the PET film was immersed in 1mL of the degradation reaction system, and irradiated with light (1 kW/m) 2 ) And carrying out degradation reaction under the condition. A control group was also set up and degradation of PET was performed under light for 4 hours with 1mL of free DuraPETase (24.3. Mu.g/mL) having the same amount of enzyme. After 4h of reaction, the samples were deactivated and the supernatants were centrifuged and tested by HPLC to determine the total amount of product mono (2-hydroxyethyl) terephthalate (MHET) and terephthalic acid (TPA).
Example 7:
first 4mg Fe is taken 3 O 4 Dispersing 2mg EDC and 2mg NHS into 2mL MES (pH, 5.5) buffer, and reacting at 150rpm in an air shaker at 25deg.C for 40min to obtain Fe 3 O 4 Activation of surface carboxyl groups and then recovery of activated Fe by magnetic separation 3 O 4 Nanoparticles, which were dispersed in 2mL of PB (50 mM, pH 7.5) buffer containing 0.4mg/mL of DuraPETase, then reacted at 10℃and 150rpm for 1 hour, and then the immobilized enzyme was separated by centrifugation and magnetic column, and the concentration of protein in the supernatant of the reaction solution before and after immobilization was measured by Bradford, and it was concluded by the principle of conservation of materials that the enzyme loading of the prepared immobilized DuraPETase was 23.9. Mu.g/mg Fe 3 O 4 . The immobilized enzyme is then configured as Fe 3 O 4 The concentration of the nanoparticle was 1mg/mL, and the enzyme content was 23.9. Mu.g/mL.
Enzymatic degradation of PET in the above reaction system under sunlight:
PET was cut into 6mm diameter discs for plastic degradation experiments. Under the condition of room temperature (25 DEG C) Immersing PET film in 1mL of the degradation reaction system under light (1 kW/m) 2 ) And carrying out degradation reaction under the condition. A control group was also set up and degradation of PET was performed under light for 4 hours with 1mL of free DuraPETase (23.9. Mu.g/mL) having the same amount of enzyme. After 4h of reaction, the samples were deactivated and the supernatants were centrifuged and tested by HPLC to determine the total amount of product mono (2-hydroxyethyl) terephthalate (MHET) and terephthalic acid (TPA).
In summary, the invention develops a novel method for improving the degradation capability of PET degrading enzyme on PET. By Fe 3 O 4 The photo-thermal capability of the PET degrading enzyme under the sunlight condition can increase the temperature of a reaction system of the PET degrading enzyme from normal temperature (25 ℃) to 46 ℃, so that the PET degrading capability of the PET degrading enzyme under the natural condition is effectively improved. In addition, is immobilized in Fe 3 O 4 Compared with free enzyme, the DuraPETase has better stability and recycling stability, and is more beneficial to industrial practical application.
The invention provides Fe 3 O 4 While nanoparticle-mediated sunlight-enhanced efficient enzymatic degradation of waste PET has been described in terms of preferred embodiments in the field, it will be apparent to those skilled in the relevant art that variations and appropriate modifications and combinations of the methods described herein can be made to practice the present technology without departing from the spirit, scope, or spirit of the invention. It is expressly intended that all such similar substitutes and modifications apparent to those skilled in the art are deemed to be included within the spirit, scope and content of the invention.
Claims (4)
1. A method for promoting PET high-efficiency enzyme degradation by using ferroferric oxide nanoparticle mediated sunlight; the method is characterized by comprising the following steps of:
(1) PET degrading enzyme and Fe 3 O 4 The nanoparticles are physically mixed, or PET degrading enzyme and Fe 3 O 4 Covalent cross-linking of the nanoparticles; obtaining a PET degrading enzyme system; fe (Fe) 3 O 4 The mass ratio of the nanoparticles to the PET degrading enzyme in physical mixing is 2-100:1;
(2) Immersing the PET film in the PET degrading enzyme system in the step (1), and then placing the PET film under sunlight irradiation for enzymatic degradation of PET;
the PET degrading enzyme is degrading enzyme DuraPETase; fe (Fe) 3 O 4 The particle size of the nano particles is 5-100 nm; fe (Fe) 3 O 4 The surface of the nanoparticle is provided with carboxyl or amino.
2. The method of PET high-efficiency enzymatic degradation of claim 1; characterized in that Fe 3 O 4 The covalent crosslinking step of the nanoparticle and the PET degrading enzyme is as follows:
1) Fe is added to 3 O 4 Dispersing the nano particles into MES buffer solution, adding EDC and NHS to activate carboxyl on the surface of the nano particles, carrying out constant-temperature concussion reaction, separating and recovering after the reaction is finished, and repeatedly cleaning the nano particles with deionized water;
2) To activated Fe 3 O 4 Adding the nano particles into PS buffer solution containing PET degrading enzyme, placing into a constant temperature air shaking table for shake reaction, separating and recovering after the reaction is finished to obtain the Fe-immobilized material 3 O 4 PET degrading enzyme on the nanoparticle.
3. A method of PET high efficiency enzymatic degradation according to claim 2; characterized in that the EDC and the magnetic Fe 3 O 4 The mass ratio of the nano particles is 0.5-2:1, and NHS and magnetic Fe are as follows 3 O 4 The mass ratio of the nano particles is 0.5-1.5:1.
4. A method of PET high efficiency enzymatic degradation according to claim 2; characterized in that the Fe 3 O 4 The mass ratio of the nano particles to the PET degrading enzyme is 5-25:1, the temperature of the constant-temperature shaking table is 3-10 ℃, the rotating speed is 50-150rpm, and the reaction time is 1-5h.
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| CN202111567913.8A CN114262723B (en) | 2021-12-20 | 2021-12-20 | Method for promoting efficient enzymatic degradation of PET (polyethylene terephthalate) by using ferroferric oxide nanoparticle-mediated sunlight |
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| CN202111567913.8A CN114262723B (en) | 2021-12-20 | 2021-12-20 | Method for promoting efficient enzymatic degradation of PET (polyethylene terephthalate) by using ferroferric oxide nanoparticle-mediated sunlight |
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| CN114262723B true CN114262723B (en) | 2024-03-15 |
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| JP2003000155A (en) * | 2001-06-26 | 2003-01-07 | Tottori Kanzume Kk | Method for producing enzymically treated fish meal and feed comprising enzymically treated fish meal formulated therein |
| CN112403408A (en) * | 2020-08-20 | 2021-02-26 | 西安理工大学 | Magnetic micro-nano material based on PET degradation product and preparation method and application thereof |
| CN113337001A (en) * | 2021-06-11 | 2021-09-03 | 浙江工业大学 | Method for degrading polyethylene glycol terephthalate by combining bacteria and enzyme |
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| JP2003000155A (en) * | 2001-06-26 | 2003-01-07 | Tottori Kanzume Kk | Method for producing enzymically treated fish meal and feed comprising enzymically treated fish meal formulated therein |
| CN112403408A (en) * | 2020-08-20 | 2021-02-26 | 西安理工大学 | Magnetic micro-nano material based on PET degradation product and preparation method and application thereof |
| CN113337001A (en) * | 2021-06-11 | 2021-09-03 | 浙江工业大学 | Method for degrading polyethylene glycol terephthalate by combining bacteria and enzyme |
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