Application of magnolol in the preparation of formulations for inhibiting Aspergillus growth and / or aflatoxin B1 biosynthesis

Abstract

This invention relates to the field of pesticide technology, specifically to the application of magnolol in the preparation of formulations for inhibiting the growth of Aspergillus flavus and / or the biosynthesis of aflatoxin B1. The present invention has found that magnolol can effectively inhibit the mycelial growth of Aspergillus flavus and completely inhibit the production of aflatoxin B1. Further research in this invention shows that magnolol inhibits fungal growth and toxin production by damaging mitochondrial function, inducing a large accumulation of intracellular reactive oxygen species, thereby disrupting the cell membrane integrity of Aspergillus flavus; at the molecular level, magnolol selectively and significantly downregulates key genes in the later stages of aflatoxin biosynthesis. aflM , aflP and aflQ The expression of magnolol was demonstrated. Applying magnolol to corn and peanut seeds effectively inhibited the production of aflatoxin B1. This invention provides new applications and candidate compounds for developing safe and efficient novel green technologies to control aflatoxin and its toxin contamination.

Description

Technical Field

[0001] This invention relates to the field of pesticide technology, specifically to the use of magnolol in the preparation of formulations for inhibiting the growth of Aspergillus flavus and / or the biosynthesis of aflatoxin B1. Background Technology

[0002] Aspergillus flavus ( Aspergillus flavus Aspergillus flavus is a saprophytic filamentous fungus widely distributed in nature. It easily infects grain and oil crops such as peanuts and corn, causing corn ear rot and peanut aspergillosis, leading to reduced crop yields and decreased quality. During storage, high moisture and suitable temperature and humidity conditions can further exacerbate the reproduction and spread of Aspergillus flavus, causing serious losses of stored grain.

[0003] More seriously, Aspergillus flavus produces aflatoxins during its growth, among which aflatoxin B1 (AFB1) is the most toxic and widespread. According to the Food and Agriculture Organization of the United Nations, approximately 25% of global crops are contaminated with fungal toxins annually, and the economic losses caused by aflatoxins amount to billions of dollars, making it the most harmful of all fungal toxins. AFB1 has been classified as a Group 1 carcinogen by the International Agency for Research on Cancer (IARC), possessing strong carcinogenic, teratogenic, mutagenic, and immunosuppressive effects. It is also highly stable to light and heat, and difficult to destroy through conventional heating. Long-term intake of AFB1 can cause toxicity to multiple organs, including the liver, nervous system, intestines, immune system, and reproductive system, seriously threatening food safety and human health.

[0004] To reduce the harm caused by AFB1, two main strategies are currently adopted: one is to degrade and detoxify contaminated agricultural products, and the other is to inhibit the growth of Aspergillus flavus and its toxin production at the source. Detoxification strategies include physical, chemical, and biological methods, but these methods generally suffer from drawbacks such as nutrient destruction, reagent residues, and poor stability. Among source inhibition strategies, natural products have attracted much attention due to their wide availability, environmental friendliness, and multi-target effects. Magnoliosol is a lignan-based natural compound, and studies have confirmed its broad-spectrum antibacterial activity. For example, it can be used to control fungal diseases in crops such as sclerotinia stem rot, sheath blight, and gray mold. For instance, Chinese patent CN113207878A discloses the use of magnoliosol as an agricultural fungicide. This compound, as a fungicide, can effectively control agricultural fungal diseases such as sclerotinia stem rot, sheath blight, gray mold, Fusarium head blight, anthracnose, bakanae disease, vine blight, wilt, and Verticillium wilt. However, the above studies all focused on the inhibitory effect of magnolol on fungal growth and did not involve Aspergillus flavus (… Aspergillus flavusThis study specifically addresses the effects of this particular toxin-producing bacterium on the biosynthesis of aflatoxin B1 (AFB1). Existing research on aflatoxin source inhibitors has shown that some natural products (such as eugenol) can inhibit AFB1 production by downregulating toxin synthesis-related genes, but their target sites differ fundamentally from those of magnolol in this invention, and their mechanisms of action have not been systematically elucidated. Therefore, developing a safe, efficient, and stable AFB1 source inhibitor based on magnolol and elucidating its mechanism of action is of great significance for the prevention and control of aflatoxin contamination. Summary of the Invention

[0005] This invention is the first to discover and confirm that honokiol can completely inhibit the production of aflatoxin B1 at a concentration ≥24 μg / mL, while significantly inhibiting the mycelial growth of Aspergillus flavus (EC). 50 (The concentration was 24.5 μg / mL). Based on this, the present invention further reveals the multi-target synergistic mechanism of magnolol in inhibiting the growth and toxin production of Aspergillus flavus, and verifies its application effect in actual agricultural products such as corn and peanuts. The present invention aims to provide a new use of magnolol in inhibiting the growth of Aspergillus flavus and the production of aflatoxin B1, and to provide a safe, efficient, and well-defined natural antibacterial agent for postharvest storage of agricultural products.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: This invention provides the use of magnolol in the preparation of formulations for inhibiting the growth of Aspergillus flavus and / or the biosynthesis of aflatoxin B1.

[0007] To further illustrate, when the concentration of magnolol in the formulation is not less than 24 μg / mL, it can completely inhibit the production of aflatoxin B1.

[0008] Furthermore, magnolol inhibits Aspergillus flavus growth and toxin production by damaging mitochondrial function and inducing intracellular reactive oxygen species accumulation.

[0009] This further demonstrates that magnolol can downregulate genes related to aflatoxin biosynthesis. aflM、aflP and aflQ The expression.

[0010] This further illustrates that magnolol is a transcriptional regulator of aflatoxin biosynthesis. aflR and aflS The expression was not significantly affected.

[0011] The present invention also provides a composition for inhibiting the growth of Aspergillus flavus and its toxin biosynthesis, comprising magnolol and an agriculturally acceptable carrier or excipient.

[0012] To further clarify, the mass percentage of magnolol is 0.01%–90%.

[0013] To further clarify, the dosage form of the composition is any one of wettable powder, emulsifiable concentrate, suspension concentrate, soluble liquid, microcapsule, or seed treatment agent.

[0014] The present invention also provides a method for inhibiting the growth of Aspergillus flavus and the production of aflatoxin B1 in agricultural products, wherein magnolol or the composition according to any one of claims 6-8 is applied to the agricultural product or its storage environment, and the concentration of magnolol on the surface of the agricultural product or in the storage environment after application is not less than 24 μg / mL.

[0015] To further clarify, the agricultural products mentioned are corn, peanuts, soybeans, cottonseed, nuts, or their processed raw materials.

[0016] The present invention has the following beneficial effects: This invention is the first to discover that magnolol can completely inhibit the production of aflatoxin B1 at a concentration ≥24 μg / mL, providing a clear and efficient dosage regimen for source control of AFB1 in agricultural products. Most existing AFB1 inhibitors derived from natural products only provide partial inhibition; this invention achieves complete inhibition, offering significant practical advantages. Through systematic detection of multiple indicators, including mitochondrial membrane potential, ATPase activity, reactive oxygen species (ROS) levels, malondialdehyde (MDA) content, and cell membrane integrity, this invention, for the first time, constructs a multi-target synergistic mechanism chain of "mitochondrial damage, ROS accumulation, and membrane disruption" in Aspergillus flavus, providing substantial evidence for the mechanism of action of magnolol. Mechanistic studies in this invention demonstrate that magnolol exerts its effects through multi-target synergy: magnolol first damages mitochondrial function, leading to mitochondrial membrane potential (MMP) depolarization and Na+... + / K + -ATPase, Ca 2+ / Mg 2+ - Decreased ATPase activity leads to a massive accumulation of intracellular reactive oxygen species (ROS), triggering oxidative stress and lipid peroxidation, and a significant increase in malondialdehyde (MDA) levels; ultimately disrupting cell membrane integrity and causing leakage of intracellular nucleic acids and proteins. At the molecular level, magnolol selectively downregulates key genes in the later stages of AFB1 biosynthesis. aflM , aflP , aflQ The expression of transcription factors, and the expression of transcription regulators. aflR and aflS No significant effect was observed. This mode of action, which "bypasses upstream regulatory factors and precisely targets later synthetic steps," is extremely rare in existing natural products, demonstrating the unique technical contribution of this invention. The actual inhibitory effect of magnolol on AFB1 production was verified in maize and peanut seed models. No AFB1 production was detected in any of the treatment groups, indicating that magnolol has good prospects for industrial application and provides a theoretical basis and candidate molecules for developing safe, efficient, and environmentally friendly novel aflatoxin B1 source inhibitors. Attached Figure Description

[0017] Figure 1 The diagram shows the inhibitory effect of magnolol on the mycelial growth of Aspergillus flavus. Figure 2 Figure showing the effect of magnolol on Aspergillus flavus mycelial biomass. Figure 3 The thin-layer chromatography results show the effect of magnolol on AFB1. Figure 4 Figure 1 shows the effect of magnolol on the cell membrane integrity of Aspergillus flavus (A: PI staining relative fluorescence intensity quantification; B: nucleic acid / protein leakage). Figure 5 Figure 1 shows the effect of magnolol on the oxidative stress level of Aspergillus flavus (A: relative fluorescence intensity of intracellular ROS; B: MDA content). Figure 6 The results of the effect of magnolol on mitochondrial function in Aspergillus flavus are shown in the figure (A: red / green fluorescence ratio of mitochondrial membrane potential; B: ATPase activity). Figure 7 The figure shows the RT-qPCR analysis results of the effect of magnolol on the expression of genes related to aflatoxin biosynthesis; Figure 8 The thin-layer chromatography results show that magnolol inhibits AFB1 in a seed infection model (A: corn; B: peanut). Detailed Implementation

[0018] All features disclosed in this specification, or all steps in all disclosed methods or processes, may be combined in any way, except for mutually exclusive features and / or steps.

[0019] Unless otherwise stated, each feature disclosed in this specification (including any appended claims and abstract) is merely one example of a series of equivalent or similar features.

[0020] Example 1: Determination of in vitro anti-aspergillus activity of magnolol This embodiment aims to determine the inhibitory effect of magnolol on the mycelial growth of Aspergillus flavus and to calculate the half-maximal effective concentration (EC50). 50 ).

[0021] The specific method is as follows: (1) Determination of mycelial growth inhibition rate: Magnoliol (purity ≥98%, CAS: 528-43-8, purchased from Macklin, Shanghai, China) was dissolved in dimethyl sulfoxide (DMSO) to prepare a stock solution of 12.8 μg / μL, which was then diluted to 0.8-6.4 μg / μL. 75 μL of the above diluted solution was mixed with 15 mL of melted YAG medium to achieve final concentrations of 4, 8, 16, 32 and 64 μg / mL (containing 0.5% DMSO), respectively. The solution was poured into plates, and after the medium solidified, 3 μL of Aspergillus flavus spore suspension (1×10⁻⁶) was inoculated in the center of the plate. 7 (Spores / mL) were incubated in a 28°C incubator for 5-7 days. Colony diameter was measured, and EC was calculated using DPS software. 50 value.

[0022] (2) Mycelial biomass determination: YES liquid medium was used as the substrate for the growth and toxin production of Aspergillus flavus. The honokiol stock solution was sterilized by filtration through a 0.22 μm sterile filter membrane and then added to 100 mL of YES medium to achieve final concentrations of 0, 24, 48, and 96 μg / mL, respectively. Subsequently, 100 μL of a pre-prepared Aspergillus flavus spore suspension (1×10⁻⁶) was inoculated into each bottle of medium. 8 (Spores / mL). Seal all Erlenmeyer flasks with sealing film and place them in a constant temperature shaking incubator at 28℃ and 160 rpm for 3 days. Collect the mycelium, dry it, and weigh it.

[0023] All experiments were independently repeated three times. Results are expressed as mean ± standard error (SE). One-way ANOVA and Dunnett's multiple comparison test were used for comparisons between groups. p A value <0.05 is considered statistically significant.

[0024] The results are as follows Figure 1 As shown, magnolol exhibits a dose-dependent inhibitory effect on the mycelial growth of Aspergillus flavus. Regression analysis revealed that the half-maximal effective concentration (EC50) of magnolol against Aspergillus flavus was... 50 It was 24.5 μg / mL (R² = 0.9910). For example... Figure 2 As shown, compared with the control group (1.78 g), the mycelial counts in the 24 μg / mL, 48 μg / mL and 96 μg / mL treatment groups decreased to 1.19 g, 1.03 g and 0.89 g, respectively, showing a clear dose-dependent effect.

[0025] Example 2: Effect of magnolol on AFB1 This embodiment evaluates the effect of magnolol on aflatoxin B1 (AFB1).

[0026] The specific method is as follows: (1) Collect the supernatant of YES medium cultured for 3 days in Example 1, add an equal volume of dichloromethane to the supernatant, and extract by vigorous shaking in a separatory funnel for 10 min. After standing and separating the layers, collect the lower organic phase. Repeat this process three times and combine all organic phases. The combined organic phase is concentrated to near dryness under reduced pressure using a rotary evaporator at 43°C, and finally diluted to volume with an appropriate amount of dichloromethane to obtain the sample to be tested.

[0027] (2) Qualitative and semi-quantitative analysis of AFB1 in the sample was performed using thin-layer chromatography. The concentrated sample extract and AFB1 standard were spotted separately onto the same silica gel thin-layer plate, and developed in a chromatography tank using a dichloromethane:acetone (9:1) mixture as the developing solvent. After development, the silica gel plate was removed, the solvent was evaporated at room temperature, and the fluorescence was observed under a 365 nm ultraviolet analyzer.

[0028] The results are as follows Figure 3 As shown, the control group had obvious AFB1 characteristic fluorescent spots, while no AFB1 fluorescent signal was detected in any of the magnolol treatment groups (24, 48, 96 μg / mL), indicating that magnolol can completely inhibit the production of AFB1 at a concentration ≥24 μg / mL.

[0029] Example 3: Assessment of Cell Membrane Integrity This embodiment investigates the effect of magnolol on the cell membrane integrity of Aspergillus flavus. The specific method is as follows: (1) Quantitative analysis of propidium iodide (PI) staining: Aspergillus flavus spores (1×10⁻⁶) were stained with PI staining. 6 Inoculate 1 mL of LYES medium with spores / mL and incubate at 28°C and 160 rpm for 2 days. Collect mycelia, wash with PBS, and treat with 0, 24, 48, or 96 μg / mL honokiol (containing 0.5% DMSO) for 24 hours. After treatment, wash the mycelia with PBS, stain with 5 μg / mL PI in the dark for 20 minutes, wash again, photograph with a fluorescence microscope, and quantify the fluorescence intensity using ImageJ software.

[0030] (2) Nucleic acid / protein leakage determination: Collect the mycelial supernatant after the above treatment and measure its absorbance at 260 nm and 280 nm.

[0031] The results are as follows Figure 4 As shown in Figure A, compared with the control group, the relative fluorescence intensity of PI in the 48 μg / mL and 96 μg / mL magnolol treatment groups increased significantly by 14.54 times and 16.48 times, respectively, indicating that cell membrane permeability increased in a dose-dependent manner. Figure 4 As shown in B, the processing group OD 260 and OD280 The values ​​were all significantly elevated, indicating increased leakage of intracellular nucleic acids and proteins, further confirming the disruption of cell membrane integrity.

[0032] Example 4: Detection of Oxidative Stress Levels This embodiment measures the levels of reactive oxygen species (ROS) and lipid peroxidation in Aspergillus flavus cells treated with magnolol.

[0033] The specific method is as follows: (1) Quantitative analysis of ROS level: The treated Aspergillus mycelium (method as in Example 3) was stained with 10 μg / mLDCFH-DA probe in the dark for 20 minutes, washed, photographed by fluorescence microscope and the fluorescence intensity was quantified by ImageJ software.

[0034] (2) MDA content determination: Aspergillus flavus was inoculated into 100 mL YES medium containing 0, 24, 48 or 96 μg / mL honokiol, and 100 μL of spore suspension (1×10) was inoculated into each bottle. 8 The mycelium was cultured at 28℃ and 160 rpm for 3 days with shaking. The mycelium was collected, rinsed, and dried. 0.2 g of mycelium was homogenized in 1 mL of 10% trichloroacetic acid. The homogenate was centrifuged at 4000 rpm and 4℃ for 10 minutes. The supernatant was mixed with an equal volume of 10% trichloroacetic acid solution containing 0.67% thiobarbituric acid. The mixture was heated at 95℃ for 20 minutes, cooled, and centrifuged. The absorbance of the supernatant at 450, 532, and 600 nm was measured. The absorbance was calculated using the formula (MDA(nmol / g) = [6.45 × (ΔA)]). 532 −ΔA 600 -0.56×ΔA 450 The MDA content is calculated as ΔA × total volume of homogenate / (volume of supernatant used for determination × fresh weight of mycelium) , where ΔA 532 = A 532 (Sample)-A 532 (Blank), ΔA 600 ΔA 450 Similarly.

[0035] The results are as follows Figure 5 As shown in Figure A, compared with the control group, the relative fluorescence intensity of intracellular reactive oxygen species (ROS) in the 48 μg / mL and 96 μg / mL magnolol treatment groups increased significantly by 2.00-fold and 3.84-fold, respectively, indicating a significant increase in intracellular ROS levels. Figure 5 As shown in B, magnolol treatment increased MDA levels in a concentration-dependent manner, with malondialdehyde (MDA) levels reaching 5.04 and 6.64 nmol / g in the 48 and 96 μg / mL treatment groups, respectively, compared to 3.10 nmol / g in the untreated control group.

[0036] Example 5: Mitochondrial Function Analysis This embodiment investigates the effect of magnolol on mitochondrial function in Aspergillus flavus.

[0037] The specific method is as follows: (1) Quantitative analysis of MMP: The treated Aspergillus mycelium (method as in Example 3) was stained with 10 μg / mL JC-1 in the dark for 30 minutes, washed and observed under a fluorescence microscope. The fluorescence intensity was quantified and the red / green fluorescence ratio was calculated using ImageJ software.

[0038] (2) ATPase activity assay: Aspergillus flavus was inoculated into 100 mL YES medium containing 0, 24, 48, and 96 μg / mL honokiol and cultured at 28℃ and 160 rpm for 3 days with shaking. Mycelia were collected, rinsed, and dried. 0.2 g of mycelia were accurately weighed and placed in a pre-cooled glass tissue homogenizer. A certain volume of pre-cooled extraction solution was added, and the homogenate was rapidly and thoroughly homogenized in an ice bath to prepare a 10% homogenate. The homogenate was centrifuged at 3500 rpm for 10 min at 4℃, and the supernatant (i.e., enzyme solution) was collected for later use. Subsequently, the corresponding control group and test tubes were set up strictly according to the instructions of the ATPase test kit provided by Nanjing Jiancheng Bioengineering Research Institute, and the Na+ in the enzyme solution was determined by phosphorus determination method. + / K + -ATPase and Ca 2+ / Mg 2+ -ATPase activity.

[0039] The results are as follows Figure 6 As shown in Figure A, compared with the control group, the green / red fluorescence ratios of the 24, 48, and 96 μg / mL magnolol treatment groups increased by 2.28-fold, 4.36-fold, and 7.42-fold, respectively, indicating mitochondrial membrane potential depolarization. Figure 6 As shown in Figure B, the activities of both ATPases were significantly inhibited in the magnolol-treated group.

[0040] Example 6: Effects of magnolol on the expression of genes related to aflatoxin synthesis Given that the 24, 48, and 96 μg / mL magnolol treatment groups in Example 2 could completely inhibit the production of AFB1 ( Figure 3Furthermore, 24 μg / mL is the lowest concentration for complete inhibition. To further clarify the regulatory role of magnolol on toxin synthesis genes and avoid detection errors caused by weak signals at low concentrations, this embodiment selected 96 μg / mL for gene expression analysis to obtain a clearer detection signal. Aspergillus flavus mycelia treated with different concentrations of magnolol (0, 96 μg / mL) for 3 days were collected, and total RNA was extracted. The expression levels of relevant genes were detected by real-time quantitative PCR (RT-qPCR). All RT-qPCR experiments were performed in triplicate, with each triplicate containing three technical replicates. Comparisons between the treatment and control groups were performed using multiple t-tests, corrected for by the Benjamini-Hochberg false discovery rate (FDR). p A value <0.05 is considered statistically significant.

[0041] The results are as follows Figure 7 As shown, magnolol can significantly downregulate the expression of key genes in the later stages of AFB1 biosynthesis. Among them, aflM The expression level was downregulated by 99.4%. aflP Down 99.9%, aflQ Downregulated by 94.8%, while transcriptional regulatory factors aflR and aflS The expression level of magnolol did not change significantly, indicating that magnolol selectively inhibits the later steps of toxin synthesis.

[0042] Example 7: Practical Application Verification of Agricultural Products This embodiment verifies the actual effect of magnolol in inhibiting AFB1 production in corn and peanut seed models.

[0043] The specific method is as follows: The protective effect of magnolol against Aspergillus flavus infection was evaluated using corn and peanut seeds. Seeds were disinfected with 0.05% sodium hypochlorite for 3 minutes, 75% ethanol for 1 minute, and rinsed three times with sterile water for surface disinfection. This experiment included a blank control group (CK), a model control group (0 μg / mL magnolol), and treatment groups (48 and 96 μg / mL magnolol). The surface-disinfected corn and peanut seeds were then inoculated with Aspergillus flavus spores (1×10⁻⁶). 5 Seeds were incubated with different concentrations of magnolol (0, 48, 96 μg / mL) for 30 minutes (CK was incubated with sterile water only), then placed in petri dishes lined with moistened sterile filter paper and cultured at 28°C in the dark for 6 days. The surface residues were collected, extracted with dichloromethane, and the AFB1 content was determined by thin-layer chromatography.

[0044] The results are as follows Figure 8 A (corn) and Figure 8As shown in B (peanut), the model control group showed obvious characteristic fluorescent spots of AFB1, while no AFB1 was detected in the 48 μg / mL and 96 μg / mL magnolol treatment groups, confirming that magnolol can completely inhibit the production of AFB1 in actual agricultural product systems.

[0045] In summary, the present invention, through the above embodiments, confirms that: (1) magnolol has a significant inhibitory effect on the growth of Aspergillus flavus mycelia, EC 100%. 50 The concentration was 24.5 μg / mL; (2) Honokiol could completely inhibit the production of aflatoxin B1 at a concentration ≥24 μg / mL; (3) The mechanism of action of honokiol includes: damaging mitochondrial function (MMP depolarization, ATPase activity inhibition) → inducing intracellular ROS accumulation and lipid peroxidation (MDA increase) → disrupting cell membrane integrity (PI staining enhancement, nucleic acid / protein leakage); (4) At the molecular level, honokiol selectively downregulates key genes in the later stage of toxin biosynthesis. aflM, aflP, aflQ The expression of transcription factors is not affected. aflR and aflS (5) In actual infection models of maize and peanut seeds, magnolol can completely inhibit the production of AFB1, showing good application prospects. The above examples, from phenotype, cell, biochemistry, molecule to practical application, progressively reveal the multi-target synergistic mechanism of magnolol in inhibiting the growth of Aspergillus flavus and the production of AFB1.

[0046] Although the present invention has been described in detail above with general descriptions and specific embodiments, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, all such modifications or improvements made without departing from the spirit of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. The use of magnolol in the preparation of formulations for inhibiting the growth of Aspergillus flavus and / or the biosynthesis of aflatoxin B1.

2. The application as described in claim 1, characterized in that, When the concentration of magnolol in the formulation is not less than 24 μg / mL, it can completely inhibit the production of aflatoxin B1.

3. The application as described in claim 1 or 2, characterized in that, Magnolol inhibits Aspergillus flavus growth and toxin production by damaging mitochondrial function and inducing intracellular reactive oxygen species accumulation.

4. The application as described in any one of claims 1–3, characterized in that, Magnolol can downregulate genes related to aflatoxin biosynthesis. aflM、aflP and aflQ The expression.

5. The application as described in claim 4, characterized in that, magnolol as a transcriptional regulator of aflatoxin biosynthesis aflR and aflS The expression was not significantly affected.

6. A composition for inhibiting the growth of Aspergillus flavus and its toxin biosynthesis, characterized in that, This includes magnolol and agriculturally acceptable carriers or excipients.

7. The composition according to claim 6, characterized in that, The mass percentage of magnolol is 0.01%–90%.

8. The composition according to claim 6 or 7, characterized in that, The composition is available in any of the following dosage forms: wettable powder, emulsifiable concentrate, suspension concentrate, soluble liquid, microcapsule, or seed treatment agent.

9. A method for inhibiting the growth of Aspergillus flavus and the production of aflatoxin B1 in agricultural products, characterized in that, Apply magnolol or the composition according to any one of claims 6–8 to agricultural products or their storage environment, such that the concentration of magnolol on the surface of the agricultural product or in the storage environment after application is not less than 24 μg / mL.

10. The method as described in claim 8, characterized in that, The agricultural products mentioned are corn, peanuts, soybeans, cottonseed, nuts, or their processed raw materials.

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