Method for evaluating antioxidant properties of different hydroxyl groups of polyphenols based on interaction model
Patent Information
- Application Number
- CN202211164119.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2022-09-23
- Publication Date
- 2025-11-07
- Estimated Expiration
- 2042-09-23
Smart Images
Figure CN115641921B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of active substances and chemical theoretical calculation technology, and relates to a method for evaluating the antioxidant properties of different hydroxyl groups of polyphenols based on an interaction model. Background Technology
[0002] Polyphenols are a class of functional components with antioxidant activity found in plants. In experimental studies, DPPH radical scavenging, ABTS radical scavenging, and superoxide anion radical scavenging experiments are commonly used to determine the antioxidant properties of phenols. However, these experimental methods can only evaluate the antioxidant properties of polyphenols at the molecular level as a whole, and are insufficient for in-depth research on the antioxidant strength of chemical groups at different sites within the polyphenol molecule.
[0003] In recent years, the rapid development of quantum chemical theoretical calculations has provided a more convenient and efficient approach for studying reaction mechanisms and structure-activity relationships. Therefore, researchers have proposed using theoretical parameters such as ΔHOF (different heat of formation), BDE (bond deionization enthalpy), and IP (ionization energy) calculated by molecular simulation software to study the antioxidant activity of polyphenols. Compared with traditional experimental methods, quantum chemical theoretical calculations have significant advantages in further improving the depth of research and providing a more intuitive understanding. However, this method still faces technical challenges when evaluating the antioxidant activity of different hydroxyl groups in polyphenols, including high computational complexity, long processing time, and a lack of intuitiveness. Summary of the Invention
[0004] To address the technical problems of large computational load, long time consumption, and abstract and unintuitive nature in the existing evaluation of the antioxidant properties of different hydroxyl groups of polyphenols, this invention provides a method for evaluating the antioxidant properties of different hydroxyl groups of polyphenols based on an interaction model. This method has the advantages of simple calculation, short time consumption, visualized result analysis, and intuitive presentation.
[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:
[0006] A method for evaluating the antioxidant activity of different hydroxyl groups in polyphenols based on an interaction model includes the following steps:
[0007] 1) Select appropriate functional small molecules based on the different phenolic hydroxyl groups in polyphenol compounds;
[0008] 2) Construct an interaction model between polyphenol compounds and functional small molecules. Phenolic hydroxyl groups at different sites in polyphenol compounds form intermolecular hydrogen bonds with functional small molecules. Calculate the bond lengths of intermolecular hydrogen bonds in the interaction model.
[0009] 3) Evaluate the antioxidant properties of hydroxyl groups at different sites in the same polyphenol compound by measuring the bond length of the intermolecular hydrogen bonds obtained in step 2).
[0010] Further, the step 2) is completed by using a molecular simulation software.
[0011] Further, in the step 2), the Dmol3 module in the Materials studio 2019 software is used to complete.
[0012] Further, in the step 2), the operating system of the Materials studio 2019 software is Windows 10, the calculation accuracy is set to medium, the basis group is set to DND-4.4, and the GGA-PW91 functional group is selected.
[0013] Further, in the step 2), the ratio of the polyphenol compound to the functional small molecule is 1:1-3.
[0014] Further, the polyphenol compound is caffeic acid CA or chlorogenic acid CGA; and the functional small molecule is 4-vinylbenzoic acid, 4-vinylphenylboronic acid, acrylic acid or acrylamide.
[0015] Further, in the step 3), for the same type of hydroxyl, the shorter the hydrogen bond length, the stronger the hydrogen bond effect, and the stronger the antioxidant property of the hydroxyl at the site.
[0016] The beneficial effects of the present application are:
[0017] 1. The present application provides a method for evaluating the antioxidant properties of different hydroxyl groups of polyphenols based on an interaction model, which utilizes the intermolecular hydrogen bond interaction between polyphenols and functional small molecules to construct interaction models of different proportions and different types, calculates the bond length of the intermolecular hydrogen bond in the interaction model, and realizes the evaluation of the antioxidant properties of different hydroxyl groups of polyphenols. At the same time, the results of enzyme inhibition activity determination are consistent with the results of antioxidant property theoretical parameter analysis, indicating that the constructed interaction model can be used as a simple method for evaluating the antioxidant properties of different phenolic hydroxyl groups in the same molecule.
[0018] 2. The present application uses simulation software and quantum chemical calculation to evaluate the antioxidant properties of hydroxyl groups through the intermolecular hydrogen bond length of the interaction model, which has the advantages of simple evaluation method, simple calculation, short time consumption, visual analysis of results, and intuitive evaluation index. Not only does it improve the research depth from the molecular level to the atomic level, but it also provides a new theoretical reference for the development of natural antioxidants and the study of phenolic compounds regulating enzyme activity. BRIEF DESCRIPTION OF DRAWINGS
[0019] Figure 1 is the surface electrostatic potential of CA and CGA molecules; figure (a) is CA, and figure (b) is CGA;
[0020] Figure 2 is the frontier orbital and ΔE of CA molecule (LUMO-HOMO) ;
[0021] Figure 3 Frontier orbitals and ΔE of CGA molecule (LUMO-HOMO) ;
[0022] Figure 4 Effect of temperature on thermodynamic parameters of CA
[0023] Figure 5 Effect of temperature on thermodynamic parameters of CGA
[0024] Figure 6 Hydroxyl oxygen atom charge of CA, CGA, HB and PH molecules
[0025] Figure 7 Complex interaction system of each hydroxyl in CA and CGA molecules with MAA in 1:1
[0026] Figure 8 Complex interaction system of the same type of hydroxyl in CA and CGA molecules with multiple MAAs simultaneously forming hydrogen bonds.
[0027] Figure 9 Complex interaction system of CA with four functional small molecules in 1:2
[0028] Figure 10 Statistical comparison of hydrogen bond lengths of the interaction system of CA and four functional small molecules
[0029] Figure 11 Inhibition ability curve of CA, CGA, HB and PH four phenolic compounds on α-glucosidase DETAILED DESCRIPTION
[0030] In order for those skilled in the art to better understand the technical solutions of the present application and to implement them, the present application will be further described below in conjunction with specific examples and drawings, but the examples should not be regarded as limiting the present application.
[0031] It should be noted that the evaluation methods and experimental methods mentioned in each example are all conventional methods unless otherwise specified; the reagents and materials used are all commercially available unless otherwise specified.
[0032] The polyphenol different hydroxyl antioxidant evaluation method based on the interaction model provided by the present application comprises the following steps:
[0033] 1) According to the different site phenolic hydroxyl groups in the polyphenol compound, select the corresponding functional small molecules;
[0034] 2) Construct the interaction model of the polyphenol compound and the functional small molecules, and the different site phenolic hydroxyl groups in the polyphenol compound form intermolecular hydrogen bonds with the functional small molecules, and calculate the bond length of the intermolecular hydrogen bonds in the interaction model;
[0035] 3) Evaluate the antioxidant properties of different hydroxyl groups in the same polyphenol compound by the bond length of intermolecular hydrogen bond in step 2).
[0036] The step 2) of the present application is completed by using molecular simulation software.
[0037] In step 2) of the present application, the Dmol3 module in Materials studio 2019 software is used.
[0038] In step 2) of the present application, the operating system of Materials studio 2019 software is Windows 10, the calculation accuracy is set to medium, the basis group is set to DND-4.4, and the GGA-PW91 functional is selected.
[0039] In step 2) of the present application, the ratio of polyphenol compound to functional small molecule is 1:1-3.
[0040] In the present application, common substances that can easily form hydrogen bonds with polyphenols are selected as functional monomers, i.e. functional small molecules.
[0041] In the present application, the polyphenol compound is caffeic acid CA or chlorogenic acid CGA; the functional small molecule is 4-vinylbenzoic acid, 4-vinylphenylboronic acid, acrylic acid or acrylamide.
[0042] In step 3) of the present application, for the same type of hydroxyl group, the shorter the hydrogen bond length, the stronger the hydrogen bond effect, and the stronger the antioxidant property of the hydroxyl group at this site.
[0043] Comparative Example 1
[0044] First, the molecular structure models of caffeic acid CA and chlorogenic acid CGA are established in the visualization interface, respectively, the Dmol3 module is used, the calculation type is selected as Geometry optimization (geometric optimization), the quality (calculation accuracy) is set to medium (medium), the functional method is selected as GGA-PW91, the basis group is set to DND-4.4, the geometric optimization is performed, and the stable structure with the lowest energy is obtained.
[0045] Then, the optimized structure is calculated for energy, the calculation type is selected as Energy (energy), the spin limit system, the electron density, the electrostatic potential, the Fukui function, the orbitals, and the population analysis are calculated from the Mulliken charge distribution, the surface electrostatic potential, the highest occupied orbital (HOMO) and the lowest unoccupied orbital (LUMO) and the energy gap ΔE (LUMO-HOMO)Aspect in-depth analysis.
[0046] In addition, the frequency calculation (Frequency) was carried out on the molecular system to obtain the corresponding dipole moment and thermodynamic parameters such as entropy and enthalpy at different temperatures. The results are shown in Figures 1-5 .
[0047] Referring to Figure 1 , it is shown that the minimum points of the electrostatic potential in the CA and CGA molecules are distributed on the O atom, indicating that the O atom is an electron-rich region and can act as a hydrogen bond acceptor; and the maximum points are distributed on the H atoms of the phenolic hydroxyl and carboxyl groups, and the H atoms on the hydroxyl and carboxyl groups are electron-poor regions and act as hydrogen bond donors.
[0048] As shown in Figure 2 and Figure 3 , the ΔE (LUMO-HOMO) of the two compounds is 2.67 eV and 2.76 eV, respectively, and the ΔE (LUMO-HOMO) value of CA is smaller, indicating that the antioxidant activity of CA is stronger than that of CGA.
[0049] Referring to Figure 4 and Figure 5 , from the results of the thermodynamic property calculation, the entropy, heat capacity and enthalpy of the system increase with the increase of temperature, and the free energy gradually decreases with the increase of temperature. The free energy results show that when the phenolic compound exists alone, its reactivity increases with the increase of temperature, and it is easy to oxidize at high temperature. The four thermodynamic parameters of CA change less with the increase of temperature, while the change of CGA is larger. The above theoretical calculation and analysis results show that the antioxidant activity of CA is stronger than that of CGA.
[0050] According to the Mulliken charge calculation results obtained above, the atomic charges of each hydroxyl group in the CA molecule and the CGA molecule are analyzed, and the absolute values of the oxygen atom charges are compared to preliminarily evaluate the antioxidant activity of the meta-phenolic hydroxyl group and the para-phenolic hydroxyl group in the CA molecule and the CGA molecule from a theoretical point of view. The results are shown in Figure 6 .
[0051] As a comparison, meta-hydroxybenzoic acid (HB) containing a meta-phenolic hydroxyl group and para-hydroxybenzoic acid (PH) containing a para-phenolic hydroxyl group are selected, and the Geometry optimization and Energy are calculated according to the method of Example 1. The Mulliken charge calculation results of each hydroxyl group in the HB molecule and the PH molecule are obtained, and the antioxidant activity of the meta-phenolic hydroxyl group HB and the para-phenolic hydroxyl group PH is preliminarily analyzed from a theoretical point of view, and compared with the CA molecule and the CGA. The results are shown in Figure 6 .
[0052] From Figure 6 A and Figure 6As shown in B, the oxygen atom charges of the meta-phenolic hydroxyl and para-phenolic hydroxyl of CA are -0.486 and -0.441, respectively, and the oxygen atom charges of the meta-phenolic hydroxyl and para-phenolic hydroxyl of CGA are -0.483 and -0.445, respectively. The greater the absolute value of the charge of the oxygen atom, the stronger the activity of the site phenolic hydroxyl, indicating that there is a positive correlation between the absolute value of the oxygen atom charge and the antioxidant activity of the phenolic hydroxyl.
[0053] In addition, the oxygen atom charges of the three hydroxyls of the quinic acid moiety in the CGA molecule are -0.524, -0.519 and -0.493, respectively. Figure 6 B), and the absolute value of the oxygen atom charge of the C4 hydroxyl is the largest, followed by the C3 hydroxyl, and finally the C1 hydroxyl.
[0054] As shown in C and D, the oxygen atom charges of the phenolic hydroxyl of m-hydroxybenzoic acid HB and the phenolic hydroxyl of p-hydroxybenzoic acid PH are -0.641 and -0.628, respectively, indicating that the antioxidant activity of the meta-phenolic hydroxyl is stronger than that of the para-phenolic hydroxyl, which is consistent with the analysis results of CA and CGA. Figure 6 Figure 6 D), the oxygen atom charges of the phenolic hydroxyl of m-hydroxybenzoic acid HB and the phenolic hydroxyl of p-hydroxybenzoic acid PH are -0.641 and -0.628, respectively, indicating that the antioxidant activity of the meta-phenolic hydroxyl is stronger than that of the para-phenolic hydroxyl, which is consistent with the analysis results of CA and CGA.
[0055] The above rules prove that our theoretical model has certain predictability, and the oxygen atom charge can preliminarily theoretically evaluate the antioxidant activity of different phenolic hydroxyls.
[0056] Example 1
[0057] The interaction model method provided by the present application is used to evaluate the antioxidant activity of different phenolic hydroxyls.
[0058] First, according to the different site phenolic hydroxyls in the polyphenol compound, the corresponding functional small molecules are selected. In this embodiment, the polyphenol compound is CA and CGA, and the functional small molecule is methacrylic acid (MAA).
[0059] Second, the complex structure of CA and CGA with a single functional small molecule, methacrylic acid (MAA), is constructed, and the hydrogen bond length of different site phenolic hydroxyls is compared by connecting at each hydroxyl site through hydrogen bonding, and the method of Comparative Example 1 is used to calculate Geometry optimization and Energy of the complex structure.
[0060] Finally, the hydrogen bond length is calculated, and the antioxidant activity of different hydroxyls is compared and evaluated according to the size of the hydrogen bond length.
[0061] Specifically, the molecular structure model of caffeic acid CA and the molecular structure model of chlorogenic acid CGA are respectively established in the visualization interface, the Dmol3 module in the Materials studio 2019 software is adopted, the calculation type is selected as Geometry optimization (geometric optimization), the quality (calculation accuracy) is set as medium, the functional method is selected as GGA-PW91, the basis group is set as DND-4.4, the geometric optimization is performed, and the stable structure with the lowest energy is obtained. Then, the optimized structure is subjected to energy calculation, the calculation type is selected as Energy, the spin limit system is calculated, the Electron density, Electrostatics, Fukui function, Orbitals, Population analysis are calculated, the Mulliken charge distribution, the surface electrostatic potential, the highest occupied orbital (HOMO) and the lowest unoccupied orbital (LUMO) and ΔE (LUMO-HOMO) The aspect is analyzed in depth. In addition, the Frequency of the molecular system is calculated to obtain the corresponding dipole moment and thermodynamic parameters such as entropy and enthalpy at different temperatures.
[0062] In order to further evaluate the activity of the same hydroxyl group in the molecule, a phenolic hydroxyl group and a single functional small molecule interaction model is constructed. In the established caffeic acid CA molecular structure model or chlorogenic acid CGA molecular structure model, a methacrylic acid (MAA) molecular structure model is established, the GGA-PW91 functional method is selected in the software, the calculation accuracy is set as medium, the basis group is set as DND-4.4, the caffeic acid CA molecular structure model and the methacrylic acid (MAA) molecular structure model are combined to form an intermolecular hydrogen bond to construct an interaction model.
[0063] The same method is adopted to combine the chlorogenic acid CGA molecular structure model and the methacrylic acid (MAA) molecular structure model to form an intermolecular hydrogen bond to construct an interaction model.
[0064] When the model is constructed, the ratio between CA and the functional small molecule is 1:1, the ratio between CGA and the functional small molecule is 1:1, and the theoretical calculation results of the interaction model are as shown in Figure 7 As shown in the table (wherein: Figure 7 A is the CA para-phenolic hydroxyl group and MAA interaction model; Figure 7 B is the CA meta-phenolic hydroxyl group and MAA interaction model; Figure 7 C is the CGA para-phenolic hydroxyl group and MAA interaction model; Figure 7 D is the CGA meta-phenolic hydroxyl group and MAA interaction model; Figure 7 E is the C1 hydroxyl group of CGA and MAA interaction model; Figure 7 F is the C4 hydroxyl group of CGA and MAA interaction model; Figure 7G is the model of the interaction between the C3 hydroxyl group of CGA and MAA.
[0065] From the hydrogen bond length results of Figure 7 It can be seen from the hydrogen bond length results of The intermolecular hydrogen bond length of the para-phenolic hydroxyl group of CA and the MAA interaction model is 2.2 A, The intermolecular hydrogen bond length of the para-phenolic hydroxyl group of CA and the MAA interaction model is 2.2 A, The intermolecular hydrogen bond length of the para-phenolic hydroxyl group of CA and the MAA interaction model is 2.2 A, The intermolecular hydrogen bond length of the C1 hydroxyl group of CGA and the MAA interaction model is 2.2 A, The intermolecular hydrogen bond length of the C4 hydroxyl group of CGA and the MAA interaction model is 2.2 A, The intermolecular hydrogen bond length of the C3 hydroxyl group of CGA and the MAA interaction model is 2.2 A, From the above intermolecular hydrogen bond lengths, it can be seen that the intermolecular hydrogen bond length formed by the para-phenolic hydroxyl group in the complex interaction system of CA and CGA is longer than that of the meta-phenolic hydroxyl group, so the meta-phenolic hydroxyl group in CA and the meta-phenolic hydroxyl group in CGA are active sites. Among the three ordinary hydroxyl groups of CGA, the C1 hydroxyl group forms the longest intermolecular hydrogen bond, followed by the C3 hydroxyl group, and finally the C4 hydroxyl group.
[0066] The antioxidant evaluation results obtained by the interaction model in this example are consistent with the preliminary evaluation results of the charge analysis in Comparative Example 1, indicating that the antioxidant evaluation method provided by the present application is reliable.
[0067] Example 2
[0068] The complex structure of CA and multiple MAAs was constructed, specifically, CA and MAA formed a complex interaction system in a ratio of 1:2.
[0069] In this example, the method provided in Example 1 was used to calculate Geometry optimization and Energy of the complex structure, and the hydrogen bond lengths of the phenolic hydroxyl groups at different sites under multiple molecular interactions were compared, and the results are shown in Table A (CA-2MAA results). Figure 8 A(CA-2MAA results).
[0070] Example 3
[0071] The complex structure of CGA and multiple MAAs was constructed, and CGA and MAA formed a complex interaction system in two ratios of 1:2 and 1:3.
[0072] In this embodiment, the method provided in Example 1 is used to calculate Geometry optimization and Energy of the complex structure, and the hydrogen bond lengths of the phenolic hydroxyl groups at different sites under the action of multiple molecules are compared, and the results are shown in Figure 8 B (CGA-2MAA results) and Figure 8 C (CGA-3MAA results) as shown.
[0073] Comparing Figure 8 A and Figure 8 B, the CA-2MAA and CGA-2MAA configurations formed by the combination of the two phenolic compounds CA and CGA with 2MAA, and the overlap of the electron clouds occurs, which proves that MAA can form a multi-site hydrogen bond recognition system with CA and CGA. And the hydrogen bond length of the meta-phenolic hydroxyl group site in the CA-2MAA action system is obviously smaller than the hydrogen bond length of the para-phenolic hydroxyl group site , which indicates that the meta-phenolic hydroxyl group has stronger antioxidant activity than the para-phenolic hydroxyl group.
[0074] At the same time, referring to Figure 8 C, among the hydrogen bonds formed by the three ordinary hydroxyl groups in CGA, the hydrogen bond length at the C4 site is the shortest and the hydrogen bond length at the C1 site is the longest
[0075] The antioxidant activity evaluation results obtained by the interaction model in this embodiment are consistent with the preliminary evaluation results of the charge analysis in Comparative Example 1, which indicates that the antioxidant activity evaluation method provided by the present application is reliable.
[0076] Examples 4 to 7
[0077] Examples 4 to 7 construct the interaction model of the CA polyphenolic hydroxyl group and different functional small molecules.
[0078] Example 4 is to construct the complex action system of CA and 4-vinylbenzoic acid (4-VBA) functional small molecules in a ratio of 1:2.
[0079] Example 5 is to construct the complex action system of CA and 4-vinylphenylboronic acid (4-VPBA) functional small molecules in a ratio of 1:2.
[0080] Example 6 is to construct the complex action system of CA and acrylic acid (AA) functional small molecules in a ratio of 1:2.
[0081] Example 7 is to construct the complex action system of CA and acrylamide (AM) functional small molecules in a ratio of 1:2.
[0082] The four groups of complex interaction systems were constructed, and the Geometry optimization and Energy of the complex structure were calculated by referring to the method described in Example 1. The hydrogen bond lengths of the phenolic hydroxyl groups at different sites were compared, and the interaction results of the polyphenol and different functional small molecules were compared to select the optimal functional small molecule. The theoretical calculation results of the interaction models of CA and the four functional small molecules are shown in Figure 9 and Figure 10 .
[0083] Figure 9 A is the interaction model of CA and 4-vinylbenzoic acid. The hydrogen bond length formed by the intermolecular phenolic hydroxyl group of CA and 4-vinylbenzoic acid is The hydrogen bond length formed by the para-phenolic hydroxyl group of CA and 4-vinylbenzoic acid is
[0084] Figure 9 B is the interaction model of CA and 4-vinylphenylboronic acid. The hydrogen bond length formed by the intermolecular phenolic hydroxyl group of CA and 4-vinylphenylboronic acid is The hydrogen bond length formed by the para-phenolic hydroxyl group of CA and 4-vinylphenylboronic acid is
[0085] Figure 9 C is the interaction model of CA and acrylic acid. The hydrogen bond length formed by the intermolecular phenolic hydroxyl group of CA and acrylic acid is The hydrogen bond length formed by the para-phenolic hydroxyl group of CA and acrylic acid is
[0086] Figure 9 D is the interaction model of CA and acrylamide. The hydrogen bond length formed by the intermolecular phenolic hydroxyl group of CA and acrylamide is The hydrogen bond length formed by the para-phenolic hydroxyl group of CA and acrylamide is
[0087] Figure 10 The hydrogen bond lengths of the interaction systems of CA and the four functional small molecules are shown in the table.
[0088] Referring to Figure 9 and Figure 10 , the hydrogen bond lengths formed by the intermolecular phenolic hydroxyl group and the four functional small molecules are all smaller than the hydrogen bond formed by the para-phenolic hydroxyl group, and the force is stronger, indicating that the antioxidant activity of the intermolecular phenolic hydroxyl group of CA is higher than that of the para-phenolic hydroxyl group. Among the four functional small molecules, the hydrogen bond length of the complex interaction system formed by acrylamide and CA is the shortest, which is the optimal functional small molecule.
[0089] The antioxidation evaluation method for the hydroxyl groups of the polyphenol compound provided in the embodiment can simply and intuitively realize the antioxidation evaluation of the hydroxyl groups at different positions of the polyphenol compound through the bond length of the intermolecular hydrogen bond formed by the interaction model, is simple and convenient to operate, greatly reduces the calculation amount, is time-saving, and makes the analysis result visualized through the calculation software, reflects the intermolecular hydrogen bond length, and intuitively obtains the antioxidation of different hydroxyl groups.
[0090] Comparative Example 2
[0091] Further, the evaluation method provided in the application is verified by using the classical in vitro α-glucosidase activity determination method. The specific process is as follows.
[0092] According to the classical in vitro α-glucosidase activity determination method, the inhibition rate of the four phenolic compounds HB, PH, CGA and CA on α-glucosidase is determined. 70 μL of phosphate buffer (0.1 mol / L, pH = 6.8) and 20 μL of α-glucosidase (20 U / mL) are added, followed by 20 μL of inhibitor, and then 20 μL of pNPG with a concentration of 5 mmol / L is added. After 15 min of reaction at 37°C, 70 μL of Na2CO3 solution (25 mmol / L) is added, and the absorbance value at 405 nm is determined by the enzyme label instrument. The blank control is without enzyme, and the control is without sample. The inhibition curves of CA, CGA, HB and PH on the activity of α-glucosidase are shown in Figure 11 .
[0093] Referring to Figure 11 , the four phenolic compounds all have good inhibition effect on α-glucosidase, and the inhibition activity on α-glucosidase increases with the increase of the molar concentration, and shows a clear dose-dependent relationship within a certain concentration range. The half-inhibition concentration IC 50 of the four phenolic compounds on α-glucosidase can be calculated from the inhibition curve. 50 The smaller the IC 50 value of the phenolic compound on the enzyme activity, the stronger the ability to inhibit the enzyme activity, and the stronger the corresponding antioxidant activity.
[0094] The results show that the inhibition ability (IC 50 = 5.09 ± 0.04 mmol / L) of CA is higher than that of CGA (IC 50 = 5.23 ± 0.08 mmol / L), and the inhibition ability (IC 50 = 4.03 ± 0.20 mmol / L) of HB is higher than that of PH (IC 50= 4.44 ± 0.38 mmol / L), which is consistent with the established antioxidant theory model results, indicating that the evaluation method provided by the present application is reliable, can be used to evaluate the antioxidant of polyphenol compounds, and is simple to operate, greatly reduces the calculation amount, and is short in time consumption.
Claims
1. A method for evaluating the antioxidant properties of different hydroxyl groups of polyphenols based on an interaction model, characterized by, The method comprises the following steps: 1) selecting a corresponding functional small molecule according to the phenolic hydroxyl groups at different sites in the polyphenol compound; 2) constructing an interaction model of the polyphenol compound and the functional small molecule, the phenolic hydroxyl groups at different sites in the polyphenol compound and the functional small molecule form intermolecular hydrogen bonds, and the bond length of the intermolecular hydrogen bonds in the interaction model is calculated; 3) evaluating the antioxidant properties of the hydroxyl groups at different sites in the same polyphenol compound by the bond length of the intermolecular hydrogen bonds in step 2); in step 3), for the same type of hydroxyl group, the shorter the hydrogen bond length, the stronger the hydrogen bond interaction, and the stronger the antioxidant property of the hydroxyl group at the site.
2. The method for evaluating the antioxidant activity of polyphenols with different hydroxyl groups based on the interaction model according to claim 1, characterized in that, The step 2) is completed by using a molecular simulation software.
3. The method for evaluating the antioxidant activity of polyphenols with different hydroxyl groups based on the interaction model according to claim 2, characterized in that, In step 2), the Dmol3 module in the Materials studio 2019 software is used.
4. The method for evaluating the antioxidant activity of polyphenols with different hydroxyl groups based on the interaction model according to claim 3, characterized in that, In step 2), the operating system of the Materials studio 2019 software is Windows 10, the calculation accuracy is set to medium, the basis group is set to DND-4.4, and the GGA-PW91 functional group is selected.
5. The method for evaluating the antioxidant activity of polyphenols with different hydroxyl groups based on the interaction model according to claim 4, characterized in that, In step 2), the ratio of the polyphenol compound to the functional small molecule is 1:1-3.
6. The method for evaluating the antioxidant activity of polyphenols with different hydroxyl groups based on the interaction model according to claim 5, characterized in that, The polyphenol compound is caffeic acid CA or chlorogenic acid CGA; and the functional small molecule is 4-vinylbenzoic acid, 4-vinylphenylboronic acid, acrylic acid or acrylamide.