A plant-derived composition for synergistically preventing and controlling pests in traditional Chinese medicine storage and its application

Abstract

The present invention provides a plant-derived composite composition and its application. The active ingredients are 2-undecanone and decanal extracted and separated from Houttuynia cordata volatile oil, and the ratios of 5:5, 7:3, 8:2 and 9:1 are measured by experiments to have a synergistic effect on the larvae of red flour beetles, wherein the contact activity is most significant when the ratio is 5:5. The raw materials of the present invention are abundant, the production process is simple, and the production cost is low. It can be extracted and separated from Houttuynia cordata volatile oil, and its safety has been recognized. The insecticidal composition provided by the present invention uses 2-undecanone and decanal as active ingredients, has a significant contact effect on Chinese medicine storage pests, is safe and environmentally friendly, and the dosage of the two components after compounding is reduced compared to when used alone, significantly improving the insecticidal effect, reducing pesticide residues, reducing environmental pollution, and having significant economic and social benefits, and is expected to be developed into a green biopesticide.

Description

Technical Field

[0001] The invention relates to the field of biological pesticides, and in particular to a plant-derived composite composition containing 2-undecanone and decanal and application thereof in preventing and controlling storage pests of traditional Chinese medicine. The two compounds are extracted and separated from Houttuynia cordata volatile oil. Background Art

[0002] Chinese medicinal materials are the foundation of the development of traditional Chinese medicine. However, pest control in the storage of Chinese medicinal materials has always been a weak link in the Chinese medicine industry. The texture and efficacy of Chinese medicinal materials change after being infested by insects, which not only causes a waste of Chinese medicinal resources, but also seriously affects the safety and efficacy of clinical medication. According to statistics, about 70% of Chinese medicinal materials are susceptible to pests, resulting in reduced safety and effectiveness, and causing economic losses of tens of billions of yuan each year. There are many types of pests in the storage of Chinese medicinal materials, with the dominant species being Coleoptera insects such as the red flour beetle, tobacco beetle, medicinal material beetle and coffee bean beetle. Among them, the red flour beetle Tribolium castaneum (Herbst) belongs to the Tenebrionidae family of the order Coleoptera. It is one of the most widespread pests in the storage of traditional Chinese medicines. In addition to direct damage, the secretion of its scent glands contains carcinogens such as benzoquinone, which makes the victim clump, change color, and stink, making it inedible. In addition, it can accelerate the reproduction of mold in stored materials under high temperature and humid conditions.

[0003] At present, chemical pesticide control is widely used in the prevention and control of pests in the storage of Chinese herbal medicines. However, the long-term and excessive use of chemical pesticides can easily lead to excessive pesticide residues, increased pest resistance, environmental pollution and other shortcomings, which has become one of the "bottlenecks" restricting the healthy development of the Chinese herbal medicine industry. Drawing on the experience of traditional anti-storage methods, finding insecticidal active ingredients from natural plants with insect repellent and mildew resistance, and making scientific and reasonable compounding is one of the effective ways to solve the abuse of chemical pesticides. With the favorable policies and the opportunity of rising market demand, it has ushered in major development opportunities. These plant secondary metabolites are easy to degrade, safe for the human and animal environment, and have diverse active ingredients and modes of action that are not easy to produce resistance, which is conducive to the pollution-free production and quality improvement of Chinese herbal medicines. In addition, combined use of drugs is the development direction of botanical insecticides. Scientific and reasonable compounding may produce a "cocktail" effect, which is one of the effective measures to improve insecticidal effects, reduce costs, and delay or overcome pest resistance. It has become an important measure in integrated pest management (IPM) and integrated resistance management (IRM). In my country, the development and registration of compound preparations have shown a steady upward trend. Currently, compound preparations account for about 34% of registered insecticide products.

[0004] Houttuynia cordata Thunb Houttuynia cordataThe fresh whole grass or dried aerial parts of Thunb. are rich in resources and are produced in provinces and regions from central, southeastern to southwestern my country. This study found that the active ingredients 2-undecanone and decanal in Houttuynia cordata volatile oil have significant contact killing activity against the Chinese medicine storage pest Tribolium castaneum, and have a synergistic effect after compounding. The safety of 2-Undecanone and decanal has been recognized. The "Sanitary Standards for the Use of Food Additives of the People's Republic of China" clearly stipulates that 2-undecanone and decanal are natural flavors allowed for use in food. Moreover, it has abundant sources, simple production processes, and low production costs. It can be extracted and separated from Houttuynia cordata volatile oil, and has a significant contact killing effect on Chinese medicine storage pests. It can reduce the use of highly toxic chemical pesticides, reduce pesticide residues, and reduce environmental pollution, with significant economic and social benefits. Summary of the invention

[0005] The present invention provides a plant-derived composite composition and its application in preventing and controlling pests in Chinese medicine storage. The composite composition uses 2-undecanone and decanal, insecticidal active ingredients in the volatilization of Houttuynia cordata, as effective ingredients, and has the advantages of high efficiency, low toxicity, and environmental friendliness. The composite composition improves its insect control effect. Through composite screening experiments, it is found that an insecticidal composition containing 2-undecanone and decanal in an appropriate proportion has an outstanding insecticidal synergistic effect, and is suitable for the prevention and control of Chinese medicine storage pests, especially for the larvae of red flour beetle. 2-Undecanone refers to: methyl nonyl ketone, and decanal refers to decanal.

[0006] The botanical insecticide composition provided by the present invention uses 2-undecanone and decanal as effective ingredients, has the advantages of significant contact killing effect on Chinese medicine storage pests, high safety, environmental protection, etc., and the dosage of the two ingredients after compounding is reduced compared with when used alone, while significantly improving the insecticide effect, increasing safety, reducing pesticide residues, reducing environmental pollution, and having significant economic and social benefits.

[0007] The present invention is achieved through the following technical solutions:

[0008] A method for preparing 2-undecanone and decanal, characterized by following the steps:

[0009] 1) Extraction of volatile oil: Take the above-ground and underground parts of Houttuynia cordata separately, place them in a volatile oil extractor, extract them by steam distillation for 4-7 hours, and dry them with anhydrous sodium sulfate to obtain the volatile oil of the above-ground and underground parts of Houttuynia cordata. The volatile oil is stored in a refrigerator at 4 ℃ for future use;

[0010] 2) Compound separation:

[0011] Separation of 2-Undecanon: Take 8-20 mL of the volatile oil from the underground part of Houttuynia cordata, use fast medium pressure purification chromatography, pass through a Flash spherical Silica column, use petroleum ether for elution, recover the solvent, and obtain 80 fractions. Fraction 11 is then passed through a Flash spherical Silica column and eluted with petroleum ether to obtain compound 2-undecanone (1.6-4.0 g);

[0012] Isolation of decanal: Take 8-20 mL of the volatile oil from the underground part of Houttuynia cordata, place it in a refrigerator at 4 ℃ for 3-7 days, crystallize, filter, and obtain 3.2-8.0 g of compound decanal;

[0013] The structures of 2-Undecanone and decanal are as follows:

[0014]

[0015] The present invention further discloses a plant-based composition for synergistically preventing and controlling pests in traditional Chinese medicine storage, characterized in that the plant-based insecticidal composition is a binary compound of 2-undecanone and decanal, the active ingredients in Houttuynia cordata volatile oil, wherein the volume ratio between 2-undecanone and decanal is 1:9-9:1. Preferably, the binary compound of 2-undecanone and decanal is 5:5, 3:7, 2:8 and 1:9, and more preferably 5:5.

[0016] The insecticide composition of 2-undecanone and decanal of the present invention is characterized in that the total weight of 2-undecanone and decanal in the preparation accounts for 1%-80% of the mass of the preparation, and the rest is adjuvants; the dosage form is any one of emulsion, microemulsion, nanoemulsion, aqueous emulsion, emulsifiable concentrate, suspension, water dispersible granules, wettable powder, microcapsule suspension, and granules. The composition also contains one or more mixed adjuvants of emulsifier, wetting agent, antioxidant, stabilizer, filler, adhesive, surfactant, defoamer, thickener, disintegrant, and dispersant.

[0017] The present invention also discloses the use of a botanical insecticide composition in preventing and controlling pests in Chinese medicine storage, wherein the pest is a coleoptera red flour beetle. Experimental results show that the contact killing activity of the main active ingredients of Houttuynia cordata, 2-undecanone and decanal, on the larvae of red flour beetles is significantly improved after compounding.

[0018] The present invention is described in more detail as follows:

[0019] 1. The present invention provides a botanical composition for synergistically preventing and controlling pests in traditional Chinese medicine storage. The botanical insecticidal composition is derived from a binary combination of 2-undecanone and decanal, the active ingredients in Houttuynia cordata volatile oil, wherein the volume ratio between 2-undecanone and decanal is 1:9-9:1.

[0020] In the above scheme, in order to ensure good insecticidal effect and synergistic effect of the plant-derived combination, the volume ratios of 2-undecanone and decanal are preferably 5:5, 3:7, 2:8 and 1:9.

[0021] 2. In the above scheme, it is more preferred that the volume ratio of 2-undecanone and decanal is 5:5. At this ratio, the insecticidal synergistic effect is most significant. It is understandable that the safety of 2-undecanone and decanal has been recognized, and their sources are abundant, convenient and easy to obtain, and can be extracted from volatile oils. In some embodiments, the composition dosage form is any one of an emulsion, a microemulsion, a nanoemulsion, an aqueous emulsion, an emulsifiable concentrate, a suspension, a water-dispersible granule, a wettable powder, a microcapsule suspension, and a granule. In some embodiments, the total weight of 2-undecanone and decanal in the preparation accounts for 1%-80% of the mass of the preparation, and the rest is an adjuvant.

[0022] In some embodiments, the composition further contains common adjuvants required for preparing pesticide formulations, which are one or a mixture of several of emulsifiers, wetting agents, antioxidants, stabilizers, fillers, binders, surfactants, defoamers, thickeners, disintegrants, and dispersants.

[0023] The present invention mainly solves the separation and identification of plant-derived ingredients 2-undecanone and decanal, the evaluation of insecticidal activity, and the study of the optimal compounding ratio, and focuses on investigating the compounding ratio of the plant-derived insecticidal composition 2-undecanone and decanal. The main difficulty lies in screening out the compound of 2-undecanone and decanal that has a synergistic effect on the larvae of Red Castanea castanea, and determining the optimal synergistic ratio.

[0024] The present invention has the following advantages:

[0025] 1. The present invention provides a botanical insecticide composition, which uses 2-undecanone and decanal, active ingredients in Houttuynia cordata volatile oil, as effective ingredients, and has the advantages of high efficiency, low toxicity, and environmental friendliness. The two ingredients have a prominent insecticidal synergistic effect after compounding, and the insecticidal activity is significant. It is suitable for the prevention and control of Chinese medicine storage pests, especially for Red Castanea castanea.

[0026] 2. The method of the present invention has abundant raw material sources, which are convenient and easy to obtain. The raw material can be extracted and separated from the volatile oil of Houttuynia cordata. The production process is simple and the production cost is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Principal component analysis of Houttuynia cordata volatile oil GC-MS analysis;

[0028] Figure 2 The chemical structures of 2-Undecanone, bornyl acetate and decanal;

[0029] Figure 3 Flow chart of separation of volatile oil from the underground part of Houttuynia cordata (8 mL);

[0030] Figure 4 Bornyl acetate H NMR spectrum;

[0031] Figure 5 Bornyl acetate C NMR spectrum;

[0032] Figure 6 2-Undecanone H NMR spectrum;

[0033] Figure 7 2-Undecanone C NMR spectrum;

[0034] Figure 8 Decanal H NMR spectroscopy;

[0035] Fig. 9 Decanal C-NMR spectroscopy;

[0036] Fig.10 Flow chart for separation of volatile oil from the underground part of Houttuynia cordata (20 mL). DETAILED DESCRIPTION

[0037] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] Example 1

[0039] Preparation and component analysis of Houttuynia cordata essential oil

[0040] The aboveground and underground parts of Houttuynia cordata were collected (location: Yichang, Hubei), placed in a volatile oil extractor, extracted by steam distillation for 4-7 hours, and dried with anhydrous sodium sulfate to obtain the volatile oils of the aboveground and underground parts of Houttuynia cordata. The volatile oils were stored in a refrigerator at 4°C for future use. The volatile oil yield was 0.04%-0.17%, and the results are shown in Table 1. The GC-MS method was used to analyze the composition of the volatile oils, and the results are shown in Table 2. A total of 65 components were identified. The main components of the aboveground part were decanal (57.71%-74.18%), dodecanal (9.70%-14.26%), etc. The main components of the underground part were 2-undecanone (24.05%-32.94%), (-)-β-pinene (14.76%-31.21%), etc. The results of GC-MS principal component analysis are shown in Figure 1 It can be seen that the composition of volatile oils from different extraction parts of Houttuynia cordata is quite different, and the composition of volatile oils from the same extraction part at different collection times is highly similar.

[0041] Table 1 Extraction information of Houttuynia cordata volatile oil

[0042]

[0043] Table 2 Chemical composition and relative percentage of Houttuynia cordata volatile oil

[0044]

[0045]

[0046]

[0047] Note: RI a : Retention index measured on a Rtx-5Sil MS column using a homogeneous series of normal alkanes; RI b : Retention index values ​​are taken from (Adams, 2007) and NIST 14.

[0048] “-”: not detected; Hcou: underground part of Houttuynia cordata; Hcoa: aerial part of Houttuynia cordata.

[0049] Example 2

[0050] Isolation and identification of bornyl acetate, 2-undecanone and decanal

[0051] Separation of bornyl acetate and 2-undecanone: Take 8-20 mL of the volatile oil from the underground part of Houttuynia cordata, use fast medium pressure purification chromatography, pass through a Flash spherical silica column, use petroleum ether for elution, recover the solvent, and obtain 80 fractions. Fraction 5 and fraction 11 are passed through a Flash spherical silica column and eluted with petroleum ether to obtain compounds bornylacetate (0.37 g) and 2-undecanone (1.6 g), respectively. The compound structure is shown in Figure 1 , separation flow chart see Figure 2 .pass 1 H-NMR and 13 The chemical structures of the obtained components were identified by C-NMR spectroscopy. Figure 3-Figure 6 .

[0052] Isolation of Decanal: Take 8 mL of volatile oil from the underground part of Houttuynia cordata, place it in a refrigerator at 4°C for 3-7 days, crystallize, filter, and obtain 3.2 g of compound decanal. 1 H-NMR and 13 The chemical structures of the obtained components were identified by C-NMR spectroscopy. Figure 7 , Figure 8 .

[0053] Example 3

[0054] Isolation and identification of bornyl acetate, 2-undecanone and decanal

[0055] Separation of bornyl acetate and 2-undecanone: Take 20 mL of the volatile oil from the underground part of Houttuynia cordata, use fast medium pressure purification chromatography, pass through a Flash spherical Silica column, use petroleum ether for elution, recover the solvent, and obtain 80 fractions. Fraction 5 and fraction 11 are passed through a Flash spherical Silica column and eluted with petroleum ether to obtain compounds bornylacetate (0.93 g) and 2-undecanone (4.0 g), respectively. See the separation flow chart Fig. 9 .pass 1 H-NMR and 13 The chemical structures of the obtained components were identified by C-NMR spectroscopy. Figure 3-Figure 6 .

[0056] Isolation of Decanal: Take 20 mL of volatile oil from the underground part of Houttuynia cordata, place it in a refrigerator at 4°C for 3-7 days, crystallize it, and filter it to obtain 8.0 g of compound decanal. 1 H-NMR and 13The chemical structures of the obtained components were identified by C-NMR spectroscopy. Figure 7 , Figure 8 .

[0057] Example 4

[0058] Test on contact toxicity of Houttuynia cordata volatile oil and its main components

[0059] Using Tribolium castaneum as the target insect, the contact activity of Houttuynia cordata volatile oil and its main components 2-undecanone, bornyl acetate and decanal were tested. According to the results of the preliminary experiment, 5 concentrations of solution were prepared for each sample as the formal experimental test drug. The Tribolium castaneum larvae that had emerged for about a week were taken out of the culture bottle and placed on an ice bag. When the test insects stopped moving, 0.5 µL of the test drug was dropped on the pronotum of the test insects. After treatment, they were placed in glass bottles, with 10 test insects in each bottle. The solvent was used as a blank control, and 5 replicates were set for each concentration. The experimental group and the control group were placed in a constant temperature incubator at a temperature of 28~30℃ and a relative humidity of 70~80% for 24 h, and the death of the test insects was observed and recorded. The LD was calculated by Probitanalysis of SPSS V20.0 statistical software 50 The results are shown in Table 3.

[0060] Positive control drugs: pyrethrins (85.4% pyrethrine I and pyrethrine II) were purchased from Dr. Ehrenstorfer, Germany.

[0061] Table 3 Contact activity of Houttuynia cordata volatile oil and its main components against Tribolium castaneum

[0062]

[0063]

[0064] Note: * Pyrethrins (pyrethrins) as positive control

[0065] As shown in Table 3, the volatile oil of Houttuynia cordata and the three monomer components isolated all have contact activity, and the contact activity against adults is stronger than that against larvae. The contact activity of the volatile oil of the underground part of Houttuynia cordata is stronger than that of the aboveground part. Among the three monomer components, 2-undecanone has the most significant contact activity, with LD 50 The contact killing activity of pyrethrins against larvae was 8.84 and 17.25 μg / head, respectively. 50 = 21.43), which shows that 2-undecanone has the potential to be developed as a botanical insecticide.

[0066] Example 5

[0067] Study on the compounding of insecticidal active ingredients of Houttuynia cordata

[0068] The three insecticidal active ingredients (2-undecanone, bornyl acetate and decanal) isolated from the volatile oil of Houttuynia cordata were studied in compounding. 2-undecanone and bornyl acetate, 2-undecanone and decanal were selected for compounding screening experiments, respectively. The interactive determination method was used to set 9 compound combinations (1:9, 2:8, 3:7, 4:6, 5:5, 6:4, 7:3, 8:2 and 9:1). The contact activity test was carried out with Tribolium castaneum as the target insect. The mortality of the test insects was observed and recorded within 24 h, and the LD 50 Theoretical LD ​​is calculated using Wadley's model. 50 Values ​​and interaction levels, LD values ​​of different mixture ratios 50 The theoretical value calculation formula is as follows:

[0069]

[0070] a is the percentage of component a in the mixture; b is the percentage of component b in the mixture; LD 50(a) is the measured LD of component a 50 Value; LD 50(b) is the measured LD of component b 50 value.

[0071] The formula for calculating the interaction coefficient of the mixture is as follows:

[0072] When R≥1.5, it is a synergistic effect, 0.5≤R<1.5 is an additive effect, and SR<0.5 is an antagonistic effect. 50 and theoretical LD 50 The interaction levels of 9 compound combinations were calculated, and the results are shown in Table 4 and Table 5:

[0073] Table 4 Contact activity of the combination of 2-Undecanone and bornyl acetate against Tribolium castaneum

[0074]

[0075] Table 5 Contact activity of the combination of 2-Undecanone and decanal against Tribolium castaneum

[0076]

[0077] As shown in Tables 4 and 5, the combination of 2-undecanone and bornyl acetate had no synergistic effect on the adults and larvae of Tribolium castaneum, and all the 9 combination ratios had an additive effect. The combination of 2-Undecanone and decanal had no synergistic effect on the adults of Tribolium castaneum, and all the 9 combination ratios had an additive effect; while the combination of 2-undecanone and decanal had a synergistic effect on the larvae of Tribolium castaneum at a ratio of 5:5, 3:7, 2:8, and 1:9, especially at 5:5, the contact activity was the most significant (LD 50 =14.81 µg / head), which was significantly better than 2-undecanone or decanal alone (LD 50 The other five ratios (9:1, 8:2, 7:3, 6:4, and 4:6) were additive. Therefore, in the study of the combination of the three active ingredients, 2-undecanone and decanal were screened to have a synergistic effect on the larvae of red flour beetle at a ratio of 5:5, 3:7, 2:8, and 1:9, and have the potential to be developed as a botanical insecticide.

[0078] Example 6

[0079] 2-Specific implementation scheme of the composition of Undecanone and decanal formulated into a biopesticide formulation:

[0080] With 2-Undecanone and decanal as active ingredients, it can be processed into any dosage form acceptable for biological pesticides as needed, among which the more preferred dosage forms are: emulsion, microemulsion, nanoemulsion, aqueous emulsion, emulsifiable concentrate, suspension, water dispersible granules, wettable powder, microcapsule suspension, and granules.

[0081] (1) Preparation of emulsion:

[0082] 2-Undecanone 20 parts, decanal 20 parts, emulsifier 20 parts, water 30 parts, other additives such as stabilizer, penetrant, etc. 10 parts. The specific production steps of the emulsion are as follows: 2-undecanone and decanal are added to the emulsifier and ground evenly, water is added to make colostrum, stabilizer and penetrant are added and stirred evenly, water is added to dilute to the full amount, and filling is performed to obtain the emulsion of the composition of the present invention.

[0083] (2) Preparation of suspension concentrate:

[0084] 30 parts of 2-Undecanone, 30 parts of decanal, 10 parts of dispersant, 10 parts of wetting agent, 5 parts of antifreeze agent, 15 parts of other additives such as defoamer, thickener, preservative, etc., and the balance of liquid carrier. The specific production steps of the suspension are as follows: 2-undecanone and decanal, dispersant, wetting agent, antifreeze agent, and water are uniformly mixed, sanded by a sand mill to obtain a stable non-sedimentary flowable liquid, and then filled to obtain the suspension of the composition of the present invention.

Claims

1. A method for preparing 2-undecanone and decanal, characterized in that Proceed as follows: 1) Extraction of volatile oil: Take the above-ground and underground parts of Houttuynia cordata separately, place them in a volatile oil extractor, extract them by steam distillation for 4-7 hours, and dry them with anhydrous sodium sulfate to obtain the volatile oil of the above-ground and underground parts of Houttuynia cordata. The volatile oil is stored in a refrigerator at 4 °C for later use; 2) Compound separation: Separation of 2-Undecanone: 8-20 mL of volatile oil from the underground part of Houttuynia cordata was taken, and purified by fast medium pressure chromatography, passed through a Flash spherical Silica column, and eluted with petroleum ether, and the solvent was recovered to obtain 80 fractions. Fraction 11 was further passed through a Flash spherical Silica column and eluted with petroleum ether to obtain compound 2-undecanone, 1.6-4.0 g; Isolation of decanal: Take 8-20 mL of the volatile oil from the underground part of Houttuynia cordata, place it in a refrigerator at 4 °C for 3-7 days, crystallize, filter, and obtain 3.2-8.0 g of compound decanal; The structures of 2-undecanone and decanal are as follows: 。 2. A plant-derived composition for synergistically controlling pests in Chinese medicine storage, characterized in that The botanical insecticide composition is derived from a binary combination of the active ingredients 2-undecanone and decanal in the Houttuynia cordata volatile oil according to claim 1, wherein the volume ratio between 2-undecanone and decanal is 1:9-9:

1.

3. A plant-derived composition for synergistically controlling pests in Chinese medicine storage as claimed in claim 2, characterized in that The binary compound ratios of 2-undecanone and decanal are 1:9, 2:8, 3:7, 4:6, 5:5, 6:4, 7:3, 8:2 and 9:

1.

4. A plant-derived composition for synergistically controlling pests in Chinese medicine storage as claimed in claim 2, characterized in that: The total weight of 2-undecanone and decanal in the preparation accounts for 1% to 80% of the preparation mass, and the rest is auxiliary agents; The dosage form is any one of emulsion, microemulsion, nanoemulsion, aqueous emulsion, emulsifiable concentrate, suspension, water-dispersible granule, wettable powder, microcapsule suspension and granule.

5. A plant-derived composition for synergistically controlling pests in Chinese medicine storage as claimed in claim 2, characterized in that: The composition also contains one or more mixed auxiliary agents selected from the group consisting of emulsifier, wetting agent, antioxidant, stabilizer, filler, adhesive, surfactant, defoamer, thickener, disintegrant and dispersant.

6. Use of the botanical insecticide composition according to claims 2-5 in preventing and controlling pests in Chinese medicine storage, wherein the pest is Tribolium castaneum of the order Coleoptera.

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