Extract of conocephalum japonicum having insect antifeedant activity, and preparation method and use thereof

Abstract

The application discloses an extract of Marchantia paleacea with insect antifeedant activity, a preparation method and application thereof, and belongs to the field of pest repellents. Radula complanata The application carries out research on insect antifeedant activity of Marchantia paleacea, extracts by heating and refluxing, extracts by different polar solvents, obtains petroleum ether phase, ethyl acetate phase, n-butanol phase and water phase, and carries out screening on the antifeedant activity by using Plutella xylostella and Helicoverpa armigera, researches show that each phase extract of Marchantia paleacea contains insect antifeedant activity, especially the petroleum ether phase and the ethyl acetate phase have the highest antifeedant activity on Plutella xylostella, and a new idea is provided for biological control.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of pest repellents, and particularly relates to a conocephalum japonicum extract with insect antifeeding activity, and a preparation method and application thereof. BACKGROUND

[0002] The information disclosed in this Background section is for the purpose of increasing an understanding of the general context of the present application and is not necessarily recognized as prior art.

[0003] Plutella xylostella is a worldwide cruciferous vegetable pest, especially harmful to crops such as Chinese cabbage, cabbage, cauliflower and rape, and has fast reproduction, strong drug resistance and great difficulty in prevention and control, which seriously affects the yield and quality of vegetables. Spodoptera litura is a worldwide major agricultural pest belonging to the family of noctuidae in the order of lepidoptera, and mainly feeds on plant leaves as larvae. Young larvae cluster on the back of leaves and leave transparent epidermis; after the third instar, they disperse and damage, enter the feeding period, and can bite leaves into notches, holes, and even eat all the leaves, leaving only the main veins. In severe cases, it can also eat fruits, stems and flower buds, causing huge yield and economic losses.

[0004] With the long-term and large-scale use of chemical pesticides, the problems of pest resistance, pesticide residues and environmental pollution are increasingly prominent, and the development of new green pesticides with high efficiency, low toxicity and environmental friendliness has become an urgent need in the field of sustainable agricultural development. Under this background, searching for lead compounds with insecticidal or antifeeding activity from plant-derived natural products is one of the important directions of biological pesticide research and development.

[0005] At present, as environmentally sensitive organisms, bryophytes not only have significant indicative effects on heavy metal pollution and atmospheric changes, but also exhibit unique advantages in agricultural pest control. The secondary metabolites contained in bryophytes include terpenes, aromatic compounds, polyacetates and alkaloids, which have a wide range of biological activities. However, compared with higher plants, the research on the biological activity of bryophytes, especially specific chemical components, is still relatively weak, and the industrial application potential has not been fully tapped.

[0006] Conocephalaceae plants are an important group of bryophytes. Although existing studies have shown that they contain a variety of secondary metabolites, there are few reports on the application of specific active ingredients, especially in the field of agricultural pest control. At present, the screening of insect antifeeding active ingredients is mainly focused on extracts from higher plants or microorganisms, and the systematic research and development of Conocephalaceae plants in this field are still blank.

[0007] Therefore, there is an urgent need in the art for a new technical solution that can efficiently and directionally screen and extract active ingredients from the plant resources of the family Radulaceae, and determine the active parts, so as to provide a scientific basis and material basis for developing new and green insect antifeedants or biological pesticides based on bryophyte sources, and to make up for the shortcomings of the prior art. SUMMARY

[0008] In view of the shortcomings of the prior art, the present application extracts the plant resources of the genus Radula Radula complanata (L.) Dumort. Figure 1 (20240728001) to study the insect antifeeding activity, and the crude extract is obtained by heating and refluxing with 85% ethanol water. Then different polar solvents are used for extraction to obtain petroleum ether phase, ethyl acetate phase, n-butanol phase and water phase mixture. The antifeeding activity of different parts is evaluated by using the model insects Plutella xylostella and Helicoverpa armigera. The study shows that each phase of Radula clara extract has insect antifeeding activity, especially the petroleum ether phase and the ethyl acetate phase have the highest antifeeding activity on Plutella xylostella, which provides a new idea for biological control.

[0009] The technical solution adopted by the present application is as follows:

[0010] In a first aspect of the present application, a preparation method of Radula clara extract with insect antifeeding activity is provided, which comprises the following steps:

[0011] The Radula clara is extracted several times by refluxing with an ethanol solution, and the extract is combined. The extract is rotary evaporated into extract paste, and the extract paste is dissolved and extracted. The extraction solvents are petroleum ether, ethyl acetate, n-butanol and / or water. After extraction, different polar part extracts of Radula clara are obtained, and the extract paste is obtained after concentration, which is the extract of different polar parts of Radula clara with insect antifeeding activity.

[0012] In one or some modes of the present application, the volume fraction of the ethanol solution is 80-85%, preferably 85%.

[0013] In one or some embodiments of the present application, the method of liquid-liquid extraction is as follows: the dissolved extract paste solution is first extracted with petroleum ether, and after extraction, water phase I and petroleum ether phase are obtained. Then ethyl acetate is added to water phase I for extraction, and water phase II and ethyl acetate phase are obtained. Finally, n-butanol is added to water phase II for extraction, and water phase III and n-butanol phase are obtained. The obtained petroleum ether phase, ethyl acetate phase, n-butanol phase and water phase III are evaporated respectively to obtain petroleum ether phase extract, ethyl acetate phase extract, n-butanol phase extract and water phase extract, which are the Radula clara extracts with insect antifeeding activity. Among them, the antifeeding activity of the petroleum ether phase extract and the ethyl acetate phase extract is particularly significant.

[0014] Preferably, the volume ratio of the extract paste solution to petroleum ether is (1-3):3.

[0015] In one or some embodiments of the present application, the extraction solvent is petroleum ether or ethyl acetate.

[0016] In a second aspect of the present application, there is provided an extract of Grimmia patens prepared by the above method.

[0017] In a third aspect of the present application, there is provided a use of the extract of Grimmia patens in the preparation of a pest repellent.

[0018] In one or some embodiments of the present application, the pest repellent has an insect antifeedant activity.

[0019] In one or some embodiments of the present application, the pest repellent repels Plutella xylostella larvae and / or Helicoverpa armigera larvae.

[0020] In a fourth aspect of the present application, there is provided a pest repellent prepared by the following method: dissolving the extract of Grimmia patens in methanol at a concentration of 1-1000 μg / mL to prepare a pest repellent.

[0021] In one or some embodiments of the present application, the concentration is 100-500 μg / mL.

[0022] Compared with the related art known to the present inventors, one of the technical solutions of the present application has the following beneficial effects:

[0023] From the perspective of ecology and sustainable development of agriculture, the present application has a dual significance: on the one hand, Grimmia patens, as a widely distributed bryophyte, has abundant secondary metabolites and is environmentally friendly, providing a green and low-toxic natural material for the research and development of new plant-derived pesticides, which helps to alleviate the problems of residue pollution and drug resistance caused by traditional chemical pesticides; on the other hand, the research results expand the application scope of bryophytes in the field of biological control, and confirm the unique value of bryophyte resources in the comprehensive management of agricultural pests, opening up a new path for the resource development of bryophytes.

[0024] The present application takes Grimmia patens plants as the object, and systematically carries out the screening and evaluation of insect antifeedant active ingredients. Through extraction, polarity extraction and biological activity determination, it is confirmed that different polarity extracts of Grimmia patens have significant antifeedant activity on Plutella xylostella and Helicoverpa armigera. The experimental results show that the petroleum ether phase, ethyl acetate phase, n-butanol phase and water phase extracts can inhibit the feeding of pests at different concentrations, and the antifeedant effect on Plutella xylostella is particularly outstanding, with a rejection rate of more than 60% in the high concentration treatment group within 72 hours, showing good biological control potential. Compared with Helicoverpa armigera, the effect of Grimmia patens extract on Plutella xylostella is more stable and efficient, which is related to the difference in diet or metabolic mechanism of the pests, providing an important clue for the subsequent targeted development of antifeedants. Attached Figure Description

[0025] The accompanying drawings, which form part of this specification, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0026] Figure 2 Bar chart of feeding area of ​​diamondback moth in petroleum ether phase. Different letters indicate significant differences between means, P≤0.05 (test), and the values ​​are the mean (n=3).

[0027] Figure 3 Different concentrations of petroleum ether were used to treat diamondback moth feeding phenomena.

[0028] Figure 4 Bar chart of the feeding area of ​​diamondback moth in ethyl acetate phase. Different letters indicate significant differences between means, P≤0.05 (test). The values ​​are the mean (n=3).

[0029] Figure 5 Different concentrations of ethyl acetate were used to treat diamondback moth feeding behavior.

[0030] Figure 6 Bar chart of the feeding area of ​​diamondback moth in the n-butanol phase. Different letters indicate significant differences between means, P≤0.05 (test), and the values ​​are the mean (n=3).

[0031] Figure 7 Different concentrations of n-butanol were used to treat the diamondback moth feeding behavior.

[0032] Figure 8 Bar chart of feeding area of ​​diamondback moth in the water phase. Different letters indicate significant differences between means. P≤0.05 (test). The values ​​are the mean (n=3).

[0033] Figure 9 Different concentrations of aqueous phase were used to treat the diamondback moth feeding behavior.

[0034] Figure 10 Bar chart of feeding area of ​​Spodoptera litura in petroleum ether phase. Different letters indicate significant differences between means, P≤0.05 (test), and the values ​​are the mean (n=3).

[0035] Figure 12 Different concentrations of petroleum ether were used to treat the feeding behavior of Spodoptera litura.

[0036] Figure 11 Bar chart of feeding area of ​​Spodoptera litura in ethyl acetate phase. Different letters indicate significant differences between means, P≤0.05 (test), and the values ​​are the mean (n=3).

[0037] Figure 13Ethyl acetate phase different concentrations of C. punctiferalis feeding phenomenon.

[0038] Figure 14 n-Butanol phase C. punctiferalis feeding area bar graph, different letters represent significant differences between means, P≤0.05 (test), values are the mean (n=3).

[0039] Figure 15 n-Butanol phase different concentrations of C. punctiferalis feeding phenomenon.

[0040] Figure 16 Water phase C. punctiferalis feeding area bar graph, different letters represent significant differences between means, P≤0.05 (test), values are the mean (n=3).

[0041] Radula complanata (L.) Dumort. Water phase different concentrations of C. punctiferalis feeding phenomenon. DETAILED DESCRIPTION

[0042] It should be noted that the following detailed description is exemplary in nature and is intended to provide further description of the application. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0043] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments in accordance with the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising," when used in this specification, specify the presence of stated features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof.

[0044] In order to enable persons skilled in the art to more clearly understand the technical solutions of the present application, the technical solutions of the present application will be described in detail below in combination with specific examples.

[0045] Example 1:

[0046] 1. Experimental materials

[0047] Radula complanata (L.) Dumort. was collected from the soil slope along the road in the Guanshan Nature Reserve in Jiangxi Province, E114°33'12, N28°33'20, H326m, and was identified as Radulaceae, Radula complanata (L.) Dumort. by morphology. It is now in the 1308 of the Science and Technology Building of Linyi University, numbered 20240728001. 3rd instar Plutella xylostella and C. punctiferalis larvae.

[0048] 2. Test method

[0049] 2.1 Extraction of Radula complanata (L.) Dumort. (family Radulaceae)

[0050] To obtain the plant *Lysimachia clethroides* (of the family Lysimachia), Figure 1 To extract the active ingredient, fresh *Pteris vittata* plant samples were pulverized. 1064 g of the pulverized *Pteris vittata* was accurately weighed and placed in a 5 L round-bottom flask. Sufficient 85% (v / v) ethanol solution was added until the *Pteris vittata* was completely submerged. The mixture was soaked at room temperature for 12 hours, then a reflux condenser was connected, and the mixture was extracted three times by reflux in an 85°C water bath, each time for 2.5 hours. After extraction, the mixture was cooled and filtered. All filtrates were combined and concentrated under reduced pressure using a rotary evaporator at a 45°C water bath until a thick, alcohol-free extract was obtained. The resulting extract was completely dissolved in 1000 mL of purified water to obtain an aqueous solution of *Pteris vittata*, which was used as the sample for subsequent fractional extraction.

[0051] 2.2 Polar Solution Extraction Experiment

[0052] Petroleum ether extraction: 70 mL of an aqueous solution containing extract of *Platycodon grandiflorus* (family Platycodonaceae) and 210 mL of petroleum ether were added to a 500 mL separatory funnel. The mixture was shaken and mixed 5 times. After standing and separating the layers, the aqueous phase and the petroleum ether phase were separated. The extraction was repeated 15 times, and the petroleum ether phase and the combined aqueous phase were combined.

[0053] Ethyl acetate extraction: Take the separated aqueous phase, add 210 mL of ethyl acetate, and extract 8 times in the same way. Combine the ethyl acetate phase and the combined aqueous phase.

[0054] n-Butanol extraction: The remaining aqueous phase was extracted three times with 210 mL of n-butanol, and the n-butanol phase and the final aqueous phase were collected.

[0055] Concentration process: The petroleum ether phase, ethyl acetate phase, n-butanol phase and final aqueous phase obtained after extraction were evaporated into extracts by rotary evaporation.

[0056] The remaining aqueous solution containing the extract of *Platycodon grandiflorus* (family Platycodonaceae) was subjected to fractional extraction using this method. The following data were obtained:

[0057] Table 1 Extract Weight

[0058]

[0059] The four-phase extract obtained after extraction and rotary evaporation was dissolved in methanol and then transferred to vials. The extract was dried to obtain a sample powder of the four phases of *Epipremnum aureum*, then sealed and stored for later use.

[0060] 2.3 Insect refusal to eat experiment

[0061] The comparative study found that the feeding rate of Plutella xylostella and Helicoverpa armigera on rape leaves was the highest. The rape leaves were punched with a 1.5 cm diameter puncher, and a total of 672 punched leaves were placed in a circular culture dish, marked and waited for processing.

[0062] The insect antifeeding activity is generally studied by leaf disc method. The specific method is to place the small leaf discs treated with the drug and the blank control into the culture dish respectively, and after a period of time, the feeding area of the insects is determined by measuring the area of the leaf disc, so as to measure the non-selective antifeeding rate.

[0063] The four-phase drug for Homomallium serratum was dissolved and treated with 2 ml of methanol, and it was divided into high, medium and low concentrations, and the specific concentration data are as follows:

[0064] Table 2 Concentration of insect antifeeding leaf disc

[0065]

[0066] The drug was added to the circular culture dish containing the leaf disc, so that the circular leaf disc was soaked in different drugs for 30 s (8 pieces per group, three parallel experiments), and it was dried. After the methanol on the leaf disc was dried, it was placed in a plastic culture dish covered with water-absorbing filter paper, 8 leaf discs were placed in each culture dish, and 5 three-year-old Plutella xylostella or Helicoverpa armigera larvae were placed in each culture dish, the culture dish was punched to ensure that the hole size was not large enough for the larvae to pass through, but the larvae were not in a completely closed space, the culture dish containing the larvae was placed in a humid environment and dark light treatment, and the leaf area was measured after 24 h, 48 h and 72 h.

[0067] 3 Results:

[0068] The following are the data results of petroleum ether phase, ethyl acetate phase, n-butanol phase and water phase, including the column chart of the average feeding area of insects, and the insect antifeeding rate data. Among them, in the significance difference test, P(F<=f)>0.05 indicates that the difference is not significant; 0.01

[0069] Antifeeding rate=(blank group feeding area-treatment group feeding area) / blank group feeding area*100% ， Here, the whole feeding area of eight leaves is taken into the formula calculation.

[0070] 3.1 Experimental results of Plutella xylostella insect antifeeding experiment

[0071] 3.1.1 Petroleum ether phase results

[0072] Table 3 Petroleum ether phase antifeeding rate

[0073]

[0074] Conclusion: From Figure 2 and Figure 3 it can be seen that compared with the blank group, the average feeding area of insects in the petroleum ether different concentration groups at 24h, 48h and 72h was reduced, indicating that the petroleum ether extract had an inhibitory effect on insect feeding. And with the increase of petroleum ether concentration, the average feeding area of insects gradually decreased, and the feeding area of the high concentration group at each time point was significantly lower than that of the low and medium concentration groups, indicating that the higher the concentration, the more significant the inhibitory effect on feeding.

[0075] From Table 3, under the same treatment time, the concentration of petroleum ether extract was positively correlated with the antifeeding rate, and high concentration extract could more effectively inhibit insect feeding. The 72h antifeeding rate of high concentration extract was 60.28%, and the 24h antifeeding rate was as high as 83.13%, showing a rapid and persistent inhibitory effect.

[0076] 3.1.2 Ethyl acetate phase results

[0077] Table 4 Ethyl acetate phase antifeeding rate

[0078]

[0079] Conclusion: From Figure 4 and Figure 5 it can be seen that compared with the blank group, the average feeding area of insects in the petroleum ether different concentration groups at 24h, 48h and 72h was reduced, indicating that the petroleum ether extract had an inhibitory effect on insect feeding. And with the increase of petroleum ether concentration, the average feeding area of insects gradually decreased.

[0080] From Table 4 data, the medium and high concentration (200-500ug / ml) antifeeding rate was more than 50% at 24-48h, but decreased slightly at 72h, indicating that the concentration of ethyl acetate extract was positively correlated with the antifeeding rate, and high concentration extract had a better effect on inhibiting insect feeding.

[0081] 3.1.3 n-butanol phase results

[0082] Table 5 n-butanol phase antifeeding rate

[0083]

[0084] Conclusion: From Figure 6 and Figure 7It can be seen that compared with the blank group, the average feeding area of insects in the n-butanol different concentration group at 24h, 48h and 72h is reduced, indicating that the n-butanol extract has an inhibitory effect on insect feeding. And with the increase of n-butanol concentration, the average feeding area of insects gradually decreases. Within each concentration group, the average feeding area of insects generally shows an upward trend as the time extends from 24h to 72h, but the growth rate of the high concentration group is relatively slow, which means that the high concentration n-butanol extract has a more lasting inhibitory effect on insect feeding.

[0085] From the data in Table 5, it can be seen that under the same treatment time, the higher the concentration, the higher the antifeeding rate. It shows that the concentration of n-butanol extract is positively correlated with the antifeeding rate, and the high concentration n-butanol extract has a stronger ability to inhibit insect feeding.

[0086] 3.1.4 Water phase results

[0087] Table 6 Water phase antifeeding rate

[0088]

[0089] Conclusion: From Figure 8 and Figure 9 it can be seen that compared with the blank group, the average feeding area of insects in the water phase different concentration group at 24h, 48h and 72h is reduced, indicating that the water phase extract can inhibit insect feeding. With the increase of water phase concentration, the average feeding area of insects gradually decreases, and the feeding area of the high concentration group at each time point is significantly lower than that of the low and medium concentration groups, indicating that the higher the concentration, the stronger the inhibitory effect on insect feeding.

[0090] From the data in Table 6, it can be seen that under the same treatment time, the higher the concentration, the higher the antifeeding rate, which shows that the concentration of water phase extract is positively correlated with the antifeeding rate, and the high concentration water phase extract has a more prominent effect on inhibiting insect feeding.

[0091] 3.2 Experimental results of insect antifeeding experiment of Spodoptera litura

[0092] 3.2.1 Petroleum ether phase results

[0093] Table 7 Petroleum ether phase antifeeding rate

[0094]

[0095] Conclusion: From Figure 10 , Figure 11 and Table 7, compared with the blank group, the average feeding area of insects in the petroleum ether different concentration group at 24h, 48h and 72h is reduced, indicating that the petroleum ether extract can inhibit insect feeding. Only the high concentration (500ug / ml) shows a significant effect at 24h, with an antifeeding rate of 87.20%, but the long-term effectiveness is weak.

[0096] 3.2.2 Ethyl acetate phase results

[0097] Table 8 Ethyl acetate phase antifeeding rate

[0098]

[0099] Conclusion: From the data in Figure 12 , Figure 13 and Table 8, compared with the blank group, the average feeding area of insects in the different concentration groups of ethyl acetate phase was reduced at 24h, 48h and 72h, indicating that the ethyl acetate phase extract had an inhibitory effect on insect feeding. Within each concentration group, the antifeeding rate significantly decreased as the time extended from 24h to 72h, and the inhibitory effect of the ethyl acetate phase extract weakened over time.

[0100] 3.2.3 n-butanol phase results

[0101] Table 9 n-butanol phase antifeeding rate

[0102]

[0103] Conclusion: From the data in Figure 14 , Figure 15 and Table 9, compared with the blank group, the average feeding area of insects in the different concentration groups of n-butanol phase was reduced at 24h, 48h and 72h, indicating that the n-butanol phase extract could inhibit insect feeding. Moreover, as the concentration of n-butanol increased, the inhibitory effect became more obvious. Under the same treatment time, the higher the concentration, the higher the antifeeding rate, and there was a positive correlation between the concentration of n-butanol phase extract and the antifeeding rate, and the high-concentration n-butanol phase extract had a stronger ability to inhibit insect feeding.

[0104] 3.2.4 Water phase results

[0105] Table 10 Water phase antifeeding rate

[0106]

[0107] Conclusion: From the data in Figure 16 , Radula complanata (L.) Dumort. and Table 10, compared with the blank group, the average feeding area of insects in the different concentration groups of water phase was reduced at 24h, 48h and 72h, indicating that the water phase extract could inhibit insect feeding. Moreover, the higher the concentration, the more obvious the inhibitory effect, and the feeding area of the high-concentration group was significantly lower than that of the low- and medium-concentration groups at each time point. Under the same treatment time, the higher the concentration, the higher the antifeeding rate, and the high-concentration extract had a stronger ability to inhibit insect feeding. However, the effect decayed quickly as the time extended.

[0108] Conclusion analysis:

[0109] In this study, the plant Marchantia paleacea of the Marchantiaceae family was used as the research objectPlutella xylostella ) were evaluated by heat reflux extraction, multi-polarity solvent extraction and leaf disc method. The main conclusions are as follows: Spodoptera ) and Spodoptera litura (Fabricius) litura ​ ) were evaluated by heat reflux extraction, multi-polarity solvent extraction and leaf disc method. The main conclusions are as follows:

[0110] The different polarity extracts of Radula marginata showed significant antifeedant effect on two lepidopteran pests, and the inhibition effect on Plutella xylostella was more prominent. Overall, Plutella xylostella was more sensitive to the extracts, which may be related to the difference in diet or metabolic mechanism of the pests.

[0111] The antifeedant rates of each phase extract were significantly improved with the increase of concentration. Although the antifeedant rates of all treatment groups decreased with time, the high concentration groups could maintain a high inhibition effect in the early stage (24-48h), which showed the characteristics of rapid onset and short-term efficacy.

[0112] The present application proves the potential of Radula marginata extract in insect control, providing a new candidate material for the development of plant-derived antifeedants. Compared with traditional chemical pesticides, it has the advantages of environmental friendliness and low toxicity, which meets the needs of green agricultural development.

[0113] The above examples are the preferred embodiments of the present application, but the embodiments of the present application are not limited by the above examples, and any changes, modifications, substitutions, combinations, simplifications made without departing from the spirit and principles of the present application shall be equivalent replacement methods, which are all included in the protection scope of the present application.

Claims

1. Use of a Grimmia pilifera extract for the preparation of a pest repellent, characterized in that, The pests repelled by the pest repellent are Plutella xylostella larvae and / or Helicoverpa armigera larvae; The pest repellent has insect antifeeding activity; The preparation method of the Radula marginata extract comprises the following steps: The Radula marginata is extracted with an ethanol solution for several times, and the extraction solutions are combined; the extraction solution is evaporated into an extraction paste, the extraction paste is dissolved, and liquid-liquid extraction is performed, and the extraction solvent is petroleum ether, ethyl acetate, n-butanol and / or water; after extraction, different-polarity Radula marginata extraction solutions are obtained, and the extraction paste is obtained after concentration, which is the Radula marginata extract with insect antifeeding activity.

2. Use according to claim 1, wherein the compound is ###0002### The method for liquid-liquid extraction is as follows: the dissolved extraction paste solution is first extracted with petroleum ether, and after extraction, water phase I and petroleum ether phase are obtained; then ethyl acetate is added to water phase I for extraction, and water phase II and ethyl acetate phase are obtained; finally, n-butanol is added to water phase II for extraction, and water phase III and n-butanol phase are obtained; the obtained petroleum ether phase, ethyl acetate phase, n-butanol phase and water phase III are evaporated respectively, and the petroleum ether phase extraction paste, ethyl acetate phase extraction paste, n-butanol phase extraction paste and water phase extraction paste are obtained, which are the Radula marginata extract with insect antifeeding activity.

3. Use according to claim 2, wherein the compound is ###0002### The volume ratio of the extraction paste solution to petroleum ether is (1-3):

3.

4. The use according to claim 1, wherein the compound is ###0002### The extraction solvent is petroleum ether or ethyl acetate.

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