Trans-2-hexenal oil-in-water nanoemulsion as well as preparation method and application thereof

Abstract

The invention provides trans-2-hexenal oil-in-water nanoemulsion as well as a preparation method and application thereof, and belongs to the technical field of biology. The nanoemulsion provided by the invention is prepared from the following raw materials: trans-2-hexenal, water and an emulsifier, the emulsifying agent is Tween-80 and Span-80, and the emulsifying agent is an emulsifier; the mass ratio of the Tween-80 to the Span-80 is 1 to (5 to 9); the trans-2-hexenal oil-in-water nanoemulsion is characterized in that the content of an emulsifier in the trans-2-hexenal oil-in-water nanoemulsion is 0.9 to 25 weight percent, and the content of trans-2-hexenal in the trans-2-hexenal oil-in-water nanoemulsion is 0.2 to 50 weight percent. According to the invention, trans-2-hexenal is used as an oil phase, water and an emulsifier are added to prepare the oil-in-water nano-emulsion, and meanwhile, the variety and dosage of the emulsifier are controlled, so that the nano-emulsion can stably exist and is not layered, and compared with direct use of trans-2-hexenal, the oil-in-water nano-emulsion has the advantages that the oil-in-water nano-emulsion is more stable; the trans-2-hexenal oil-in-water nanoemulsion has a better effect of inhibiting the germination of aegilops tauschii seeds.

Description

Technical Field

[0001] This invention belongs to the field of biotechnology, specifically relating to a trans-2-hexenal oil-in-water nanoemulsion, its preparation method, and its application. Background Technology

[0002] Trans-2-hexenal (T2H), also known as leaf aldehyde, is a typical plant-derived volatile organic compound (VOC) with excellent environmental compatibility, making it a natural active substance with great development potential. Jointed goatgrass (Alternaria alternata) is a difficult-to-control weed in wheat fields, currently spreading to at least 15 major wheat-producing provinces, seriously threatening wheat production and causing yield reductions of 20%–30%, or even complete crop failure in some areas. Due to the close relationship between jointed goatgrass and wheat, and their similar physiological and biochemical characteristics, there is an extreme shortage of chemical agents for selective control of jointed goatgrass in wheat fields, necessitating the development of green compounds or green control technologies. Previous studies have confirmed that trans-2-hexenal has a significant inhibitory effect on jointed goatgrass seed germination, showing potential for development as a weed germination inhibitor and targeted reduction of the soil jointed goatgrass seed bank. However, in actual soil application scenarios, trans-2-hexenal suffers from core defects such as excessively rapid volatilization and poor soil mobility, making it difficult to maintain an effective concentration in the soil and significantly weakening its inhibitory effect on jointed goatgrass seed germination. Therefore, overcoming the physicochemical defects of trans-2-hexenal and improving its inhibitory effect on jointed goatgrass seed germination is a pressing technical challenge in the field of green weed control.

[0003] In view of the shortcomings of the existing technology and the actual prevention and control needs of the industry, this invention is proposed. Summary of the Invention

[0004] The purpose of this invention is to provide a trans-2-hexenal oil-in-water nanoemulsion, its preparation method, and its application. The trans-2-hexenal oil-in-water nanoemulsion provided by this invention exhibits a better inhibitory effect on the germination of jointed goatgrass seeds.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a trans-2-hexenal oil-in-water nanoemulsion, prepared from the following raw materials: trans-2-hexenal, water, and an emulsifier; The emulsifiers are Tween-80 and Span-80; the mass ratio of Tween-80 to Span-80 is 1:(5~9). The trans-2-hexenal oil-in-water nanoemulsion contains 0.9-25 wt% emulsifier and 0.2-50 wt% trans-2-hexenal.

[0006] Preferably, the raw materials for the trans-2-hexenal oil-in-water nanoemulsion also include a co-emulsifier.

[0007] Preferably, the emulsifier includes sodium alginate or chitosan.

[0008] Preferably, when the co-emulsifier is sodium alginate, the content of sodium alginate in the trans-2-hexenal oil-in-water nanoemulsion is ≤0.05wt%.

[0009] Preferably, when the co-emulsifier is chitosan, the chitosan content in the trans-2-hexenal oil-in-water nanoemulsion is ≥0.45wt%.

[0010] Preferably, when the co-emulsifier is chitosan, the raw materials for the trans-2-hexenal oil-in-water nanoemulsion also include acetic acid.

[0011] Preferably, the mass ratio of acetic acid to water is (0.01~0.1):1.

[0012] The present invention also provides a method for preparing trans-2-hexenal oil-in-water nanoemulsion as described in the above technical solution, comprising: mixing emulsifier, water and trans-2-hexenal and then performing shearing treatment to obtain trans-2-hexenal oil-in-water nanoemulsion; When the raw materials include a co-emulsifier and acetic acid, the emulsifier, water, trans-2-hexenal, co-emulsifier and acetic acid are mixed and then sheared to obtain trans-2-hexenal oil-in-water nanoemulsion.

[0013] Preferably, the shearing rate is 4000~5000 rpm and the shearing time is 4~10 min.

[0014] The present invention also provides the application of the trans-2-hexenal water-in-oil nanoemulsion described in the above technical solution or the trans-2-hexenal water-in-oil nanoemulsion prepared by the preparation method described in the above technical solution in inhibiting the germination of jointed goatgrass seeds.

[0015] This invention provides a trans-2-hexenal oil-in-water nanoemulsion, prepared from the following raw materials: trans-2-hexenal, water, and an emulsifier; the emulsifier is Tween-80 and Span-80; the mass ratio of Tween-80 to Span-80 is 1:(5~9); the content of the emulsifier in the trans-2-hexenal oil-in-water nanoemulsion is 0.9~25wt%, and the content of trans-2-hexenal is 0.2~50wt%. This invention uses trans-2-hexenal as the oil phase, adding water and an emulsifier to prepare an oil-in-water nanoemulsion. Simultaneously controlling the type and amount of the emulsifier ensures the nanoemulsion remains stable and does not separate. Compared to directly using trans-2-hexenal, the trans-2-hexenal oil-in-water nanoemulsion exhibits better germination inhibition effect on jointed goatgrass seeds. The results of the examples show that, with the same amount of trans-2-hexenal, the germination rate of *Gnaphalium affine* was 90% when trans-2-hexenal was used directly, while the germination rate of *Gnaphalium affine* was reduced to 60% when trans-2-hexenal was used in an oil-in-water nanoemulsion. Attached Figure Description

[0016] Figure 1 The dispersion of methylene blue solution and Sudan III solution in trans-2-hexenal oil-in-water nanoemulsion prepared in Example 9; Figure 2 Stability graphs of the trans-2-hexenal oil-in-water nanoemulsion prepared in Example 9 after dilution by 10-fold, 100-fold, and 1000-fold. Figure 3 Particle size, polydispersity index and zeta potential of trans-2-hexenal oil-in-water nanoemulsion prepared in Example 9; Figure 4 The inhibitory effect of trans-2-hexenal and the trans-2-hexenal oil-in-water nanoemulsion prepared in Example 9 on the germination of jointed barley seeds is shown in the figure. Detailed Implementation

[0017] This invention provides a trans-2-hexenal oil-in-water nanoemulsion, which is prepared from the following raw materials: trans-2-hexenal, water, and emulsifier.

[0018] In one embodiment, the purity of the trans-2-hexenal is 98%.

[0019] In one implementation method, the water is deionized water.

[0020] In this invention, the emulsifiers are Tween-80 and Span-80; the mass ratio of Tween-80 to Span-80 is 1:(5~9). As one embodiment, the mass ratio of Tween-80 to Span-80 can specifically be 1:5, 1:6, 1:7, 1:8, or 1:9. By using the above-mentioned emulsifiers and controlling their mass ratio, this invention enables the nanoemulsion to remain stable and prevent layering.

[0021] In this invention, the emulsifier content in the trans-2-hexenal oil-in-water nanoemulsion is 0.9~25wt%. As one embodiment, the emulsifier content in the trans-2-hexenal oil-in-water nanoemulsion can specifically be 0.91wt%, 1wt%, 5wt%, 10wt%, 15wt%, 20wt%, or 25wt%.

[0022] In this invention, the content of trans-2-hexenal in the trans-2-hexenal oil-in-water nanoemulsion is 0.2~50 wt%. As one embodiment, the content of trans-2-hexenal in the trans-2-hexenal oil-in-water nanoemulsion can specifically be 0.5 wt%, 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, 10 wt%, 20 wt%, 30 wt%, 40 wt%, or 50 wt%.

[0023] As one embodiment, the raw materials for the trans-2-hexenal oil-in-water nanoemulsion also include a co-emulsifier.

[0024] In one embodiment, the co-emulsifier includes sodium alginate or chitosan.

[0025] In one embodiment, when the co-emulsifier is sodium alginate, the content of sodium alginate in the trans-2-hexenal oil-in-water nanoemulsion is ≤0.05wt%. In another embodiment, the content of sodium alginate may specifically be 0.05wt%, 0.04wt%, 0.03wt%, or 0.02wt%.

[0026] In one embodiment, when the co-emulsifier is chitosan, the chitosan content in the trans-2-hexenal oil-in-water nanoemulsion is ≥0.45wt%. In another embodiment, the chitosan content may specifically be 0.45wt%, 0.5wt%, 0.55wt%, or 0.6wt%.

[0027] As one implementation method, when the co-emulsifier is chitosan, the raw materials of the trans-2-hexenal oil-in-water nanoemulsion also include acetic acid.

[0028] In one embodiment, the mass ratio of acetic acid to water can be (0.01~0.1):1.

[0029] This invention uses trans-2-hexenal as the oil phase, and adds water and emulsifiers to prepare an oil-in-water nanoemulsion. At the same time, the type of emulsifier and the amount of each component are controlled so that the nanoemulsion can exist stably without stratification. The droplet size of the nanoemulsion is smaller and the specific surface area is larger. Compared with the direct use of trans-2-hexenal, the trans-2-hexenal oil-in-water nanoemulsion has a better inhibitory effect on the germination of jointed goatgrass seeds.

[0030] The present invention also provides a method for preparing trans-2-hexenal oil-in-water nanoemulsion as described in the above technical solution, comprising: mixing emulsifier, water and trans-2-hexenal and then performing shearing treatment to obtain trans-2-hexenal oil-in-water nanoemulsion; When the raw materials include a co-emulsifier and acetic acid, the emulsifier, water, trans-2-hexenal, co-emulsifier and acetic acid are mixed and then sheared to obtain trans-2-hexenal oil-in-water nanoemulsion.

[0031] As one implementation method, the mixture of emulsifier, water and trans-2-hexenal can be: mixing the emulsifier and water, and then adding trans-2-hexenal.

[0032] When the raw materials of trans-2-hexenal oil-in-water nanoemulsion also include sodium alginate as a co-emulsifier, the present invention mixes sodium alginate and water, then adds the emulsifier, and then adds trans-2-hexenal.

[0033] When the raw materials of trans-2-hexenal oil-in-water nanoemulsion also include the co-emulsifier chitosan and acetic acid, the present invention mixes acetic acid and water, then adds chitosan, vortexes at 65~75℃ for 5~15 minutes, cools down to 20~30℃, and then adds the emulsifier and trans-2-hexenal in sequence.

[0034] In one embodiment, the shearing rate is 4000~5000 rpm; the shearing time is 4~10 min; and the shearing is performed in a shearing machine.

[0035] The present invention also provides the application of the trans-2-hexenal water-in-oil nanoemulsion described in the above technical solution or the trans-2-hexenal water-in-oil nanoemulsion prepared by the preparation method described in the above technical solution in inhibiting the germination of jointed goatgrass seeds.

[0036] The present invention does not impose any special limitations on the operation of the application, and any technical solution known to those skilled in the art can be used.

[0037] The technical solutions of this invention will be clearly and completely described below with reference to the embodiments thereof. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0038] Example 1 A trans-2-hexenal oil-in-water nanoemulsion is prepared from trans-2-hexenal, deionized water, and an emulsifier. The emulsifiers are Tween-80 and Span-80, with a mass ratio of 1:9. The trans-2-hexenal content in the trans-2-hexenal oil-in-water nanoemulsion is 11.1 wt%, the emulsifier content is 11.1 wt%, and the balance is deionized water. The preparation method of the trans-2-hexenal oil-in-water nanoemulsion is as follows: 0.1g Tween-80 and 0.9g Span-80 are added to 7g deionized water and sheared at 5000rpm for 5min using a shearing machine. Then, 1g trans-2-hexenal is added and sheared at 4000rpm for 5min using a shearing machine to obtain the trans-2-hexenal oil-in-water nanoemulsion.

[0039] Example 2 A trans-2-hexenal oil-in-water nanoemulsion is prepared from trans-2-hexenal, deionized water, and an emulsifier. The emulsifiers are Tween-80 and Span-80, with a mass ratio of 1:9. The trans-2-hexenal content in the trans-2-hexenal oil-in-water nanoemulsion is 0.5 wt%, the emulsifier content is 1 wt%, and the balance is deionized water. The preparation method of the trans-2-hexenal oil-in-water nanoemulsion is as follows: 0.01g Tween-80 and 0.09g Span-80 are added to 9.85g deionized water, and then 0.05g trans-2-hexenal is added. The mixture is sheared at 4000rpm for 5min to obtain the trans-2-hexenal oil-in-water nanoemulsion.

[0040] Example 3 A trans-2-hexenal oil-in-water nanoemulsion is prepared from trans-2-hexenal, deionized water, and an emulsifier. The emulsifiers are Tween-80 and Span-80, with a mass ratio of 1:5. The trans-2-hexenal content in the trans-2-hexenal oil-in-water nanoemulsion is 0.5 wt%, the emulsifier content is 0.91 wt%, and the balance is deionized water. The preparation method of the trans-2-hexenal oil-in-water nanoemulsion is as follows: 0.015g Tween-80 and 0.075g Span-80 are added to 9.8g deionized water and sheared at 4000rpm for 5min. Then, 0.05g trans-2-hexenal is added and sheared at 4000rpm for 5min to obtain the trans-2-hexenal oil-in-water nanoemulsion.

[0041] Example 4 A trans-2-hexenal oil-in-water nanoemulsion is prepared from trans-2-hexenal, deionized water, and an emulsifier. The emulsifiers are Tween-80 and Span-80, with a mass ratio of 1:9. The trans-2-hexenal content in the trans-2-hexenal oil-in-water nanoemulsion is 1 wt%, the emulsifier content is 2.5 wt%, and the balance is deionized water. The preparation method of the trans-2-hexenal oil-in-water nanoemulsion is as follows: 0.025g Tween-80 and 0.225g Span-80 are added to 9.65g deionized water, and then 0.1g trans-2-hexenal is added. The mixture is sheared at 5000rpm for 5min to obtain the trans-2-hexenal oil-in-water nanoemulsion.

[0042] Example 5 A trans-2-hexenal oil-in-water nanoemulsion is prepared from trans-2-hexenal, deionized water, and an emulsifier. The emulsifiers are Tween-80 and Span-80, with a mass ratio of 1:9. The trans-2-hexenal content in the trans-2-hexenal oil-in-water nanoemulsion is 50 wt%, the emulsifier content is 10 wt%, and the balance is deionized water. The preparation method of the trans-2-hexenal oil-in-water nanoemulsion is as follows: 0.1g Tween-80 and 0.9g Span-80 are added to 4g deionized water, then 5g trans-2-hexenal is added, and the mixture is sheared at 5000rpm for 5min to obtain the trans-2-hexenal oil-in-water nanoemulsion.

[0043] Example 6 A trans-2-hexenal oil-in-water nanoemulsion is prepared from trans-2-hexenal, deionized water, acetic acid, emulsifier, and co-emulsifier (chitosan). The emulsifiers are Tween-80 and Span-80, with a mass ratio of 1:9. The trans-2-hexenal oil-in-water nanoemulsion contains 2 wt% trans-2-hexenal, 5 wt% emulsifier, 0.5 wt% co-emulsifier, 0.9 wt% acetic acid, and the balance is deionized water. The preparation method of the trans-2-hexenal oil-in-water nanoemulsion is as follows: 0.093g of acetic acid is dissolved in 9.3g of deionized water (the mass ratio of acetic acid to deionized water is 0.01:1), 0.05g of chitosan is added, and the mixture is placed in a 70℃ water bath and vortexed for 10min to fully dissolve it. The temperature is then lowered to 25℃, and 0.05g of Tween-80, 0.45g of Span-80 and 0.2g of trans-2-hexenal are added. The mixture is sheared at 5000rpm for 5min to obtain the trans-2-hexenal oil-in-water nanoemulsion.

[0044] Example 7 A trans-2-hexenal oil-in-water nanoemulsion is prepared from trans-2-hexenal, deionized water, emulsifier, and co-emulsifier (sodium alginate). The emulsifiers are Tween-80 and Span-80, with a mass ratio of 1:9. The trans-2-hexenal content in the trans-2-hexenal oil-in-water nanoemulsion is 2 wt%, the emulsifier content is 5 wt%, the co-emulsifier content is 0.05 wt%, and the balance is deionized water. The preparation method of the trans-2-hexenal oil-in-water nanoemulsion is as follows: 0.005g of sodium alginate is added to 9.295g of deionized water, followed by 0.05g of Tween-80, 0.45g of Span-80 and 0.2g of trans-2-hexenal. The mixture is sheared at 5000rpm for 5min to obtain the trans-2-hexenal oil-in-water nanoemulsion.

[0045] Example 8 A trans-2-hexenal oil-in-water nanoemulsion is prepared from trans-2-hexenal, deionized water, acetic acid, emulsifier, and co-emulsifier (chitosan). The emulsifiers are Tween-80 and Span-80, with a mass ratio of 1:9. The trans-2-hexenal oil-in-water nanoemulsion contains 0.98 wt% trans-2-hexenal, 2.46 wt% emulsifier, 0.49 wt% co-emulsifier, and 0.95 wt% acetic acid, with the balance being deionized water. The preparation method of the trans-2-hexenal oil-in-water nanoemulsion is as follows: 0.0965g of acetic acid is dissolved in 9.65g of deionized water (the mass ratio of acetic acid to deionized water is 0.01:1), 0.05g of chitosan is added, and the mixture is placed in a 70℃ water bath and vortexed for 10min to fully dissolve it. The temperature is then lowered to 25℃, and 0.025g of Tween-80, 0.225g of Span-80 and 0.1g of trans-2-hexenal are added. The mixture is sheared at 5000rpm for 5min to obtain the trans-2-hexenal oil-in-water nanoemulsion.

[0046] Example 9 A trans-2-hexenal oil-in-water nanoemulsion is prepared from trans-2-hexenal, deionized water, and an emulsifier. The emulsifiers are Tween-80 and Span-80, with a mass ratio of 1:9. The trans-2-hexenal content in the trans-2-hexenal oil-in-water nanoemulsion is 2 wt%, the emulsifier content is 5 wt%, and the balance is deionized water. The preparation method of the trans-2-hexenal oil-in-water nanoemulsion is as follows: 0.05g Tween-80 and 0.45g Span-80 are added to 9.3g deionized water, and then 0.2g trans-2-hexenal is added. The mixture is sheared at 5000rpm for 5min to obtain the trans-2-hexenal oil-in-water nanoemulsion.

[0047] Comparative Example 1 Add 7.5g of Tween-80 to 19.5g of deionized water and shear at 5000rpm for 5min. Then add 3g of trans-2-hexenal and shear at 4000rpm for 5min to obtain nanoemulsion.

[0048] Comparative Example 2 Add 7.5g of Tween-80 to 19.5g of deionized water and shear at 2400rpm for 20min. Then add 3g of trans-2-hexenal and shear at 3000rpm for 30min to obtain nanoemulsion.

[0049] Comparative Example 3 Add 0.2g Tween-80 and 0.8g Span-80 to 7g deionized water and shear at 5000rpm for 5min. Then add 1g trans-2-hexenal and shear at 4000rpm for 5min to obtain nanoemulsion.

[0050] Comparative Example 4 Add 0.3g Tween-80 and 0.7g Span-80 to 7g deionized water and shear at 5000rpm for 5min. Then add 1g trans-2-hexenal and shear at 4000rpm for 5min to obtain nanoemulsion.

[0051] Comparative Example 4 Add 0.4g Tween-80 and 0.6g Span-80 to 7g deionized water and shear at 5000rpm for 5min. Then add 1g trans-2-hexenal and shear at 4000rpm for 5min to obtain nanoemulsion.

[0052] Comparative Example 5 Add 0.5g Tween-80 and 0.5g Span-80 to 7g deionized water and shear at 5000rpm for 5min. Then add 1g trans-2-hexenal and shear at 4000rpm for 5min to obtain nanoemulsion.

[0053] Comparative Example 6 Add 0.6g Tween-80 and 0.4g Span-80 to 7g deionized water and shear at 5000rpm for 5min. Then add 1g trans-2-hexenal and shear at 4000rpm for 5min to obtain nanoemulsion.

[0054] Comparative Example 7 Add 0.7g Tween-80 and 0.3g Span-80 to 7g deionized water and shear at 5000rpm for 5min. Then add 1g trans-2-hexenal and shear at 4000rpm for 5min to obtain nanoemulsion.

[0055] Comparative Example 8 Add 0.8g Tween-80 and 0.2g Span-80 to 7g deionized water and shear at 5000rpm for 5min. Then add 1g trans-2-hexenal and shear at 4000rpm for 5min to obtain nanoemulsion.

[0056] Comparative Example 9 Add 0.9g Tween-80 and 0.1g Span-80 to 7g deionized water and shear at 5000rpm for 5min. Then add 1g trans-2-hexenal and shear at 4000rpm for 5min to obtain nanoemulsion.

[0057] Comparative Example 10 Add 0.1g sodium alginate to 6.9g deionized water, then add 0.2g Tween-80, 1.8g Span-80 and 1g trans-2-hexenal, and shear at 5000rpm for 10min to obtain nanoemulsion.

[0058] Comparative Example 11 0.1667 g n-butanol, 0.0552 g PEG-60 hydrogenated castor oil, and 0.281 g sodium dodecyl sulfate were added to 6.5 g deionized water and sheared at 5000 rpm for 5 min to obtain nanoemulsion.

[0059] Comparative Example 12 Add 0.6g Tween-80 and 5.4g Span-80 to 1.6g deionized water, then add 2.4g trans-2-hexenal, and shear at 5000rpm for 5min to obtain nanoemulsion.

[0060] Comparative Example 13 Add 0.06g Tween-80 and 0.54g Span-80 to 4g deionized water, then add 5.4g trans-2-hexenal, and shear at 5000rpm for 5min to obtain nanoemulsion.

[0061] Comparative Example 14 Add 0.35g Tween-80 and 3.15g Span-80 to 1.5g deionized water, then add 5g trans-2-hexenal, and shear at 5000rpm for 5min to obtain nanoemulsion.

[0062] Comparative Example 15 Add 0.025g sodium alginate to 9.275g deionized water, then add 0.05g Tween-80, 0.45g Span-80 and 0.2g trans-2-hexenal. Shear the mixture at 5000rpm for 5min to obtain nanoemulsion.

[0063] Comparative Example 16 Dissolve 0.093g of acetic acid in 9.3g of deionized water, add 0.03g of chitosan, vortex in a 70℃ water bath for 10min, then add 0.05g of Tween-80, 0.45g of Span-80 and 0.2g of trans-2-hexenal, and shear at 5000rpm for 5min to obtain nanoemulsion.

[0064] Comparative Example 17 Add 0.01g sodium alginate to 9.29g deionized water, then add 0.05g Tween-80, 0.45g Span-80 and 0.2g trans-2-hexenal. Shear the mixture at 5000rpm for 5min to obtain nanoemulsion.

[0065] Comparative Example 18 Add 0.01g of lecithin to 9.29g of deionized water, then add 0.05g of Tween-80, 0.45g of Span-80 and 0.2g of trans-2-hexenal. Shear the mixture at 5000rpm for 5min to obtain nanoemulsion.

[0066] Comparative Example 19 Add 0.005g sodium alginate and 1g glycerol to 8.295g deionized water, then add 0.05g Tween-80, 0.45g Span-80 and 0.2g trans-2-hexenal. Shear the mixture at 5000rpm for 5min to obtain nanoemulsion.

[0067] Comparative Example 20 Add 0.005g sodium alginate and 1g n-butanol to 8.295g deionized water, then add 0.05g Tween-80, 0.45g Span-80 and 0.2g trans-2-hexenal. Shear the mixture at 5000rpm for 5min to obtain nanoemulsion.

[0068] Comparative Example 21 0.01g sodium alginate and 0.125g n-butanol were added to 9.165g deionized water, followed by 0.05g Tween-80, 0.45g Span-80 and 0.2g trans-2-hexenal. The mixture was sheared at 5000rpm for 5min to obtain nanoemulsion.

[0069] Comparative Example 22 0.01g sodium alginate and 0.167g n-butanol were added to 9.123g deionized water, followed by 0.05g Tween-80, 0.45g Span-80 and 0.2g trans-2-hexenal. The mixture was sheared at 5000rpm for 5min to obtain nanoemulsion.

[0070] Comparative Example 23 0.01g sodium alginate and 0.125g glycerol were added to 9.165g deionized water, followed by 0.05g Tween-80, 0.45g Span-80 and 0.2g trans-2-hexenal. The mixture was sheared at 5000rpm for 5min to obtain nanoemulsion.

[0071] Comparative Example 24 0.01g sodium alginate and 0.167g glycerol were added to 9.123g deionized water, followed by 0.05g Tween-80, 0.45g Span-80 and 0.2g trans-2-hexenal. The mixture was sheared at 5000rpm for 5min to obtain nanoemulsion.

[0072] Test Example 1 The nanoemulsions prepared in Examples 1-9 and Comparative Examples 1-24 were placed in clean containers and left at room temperature for 24 hours. The layering of the samples was observed, and the particle size of the nanoemulsions prepared in Examples 1-9 and Comparative Examples 1-24 was tested. The results are shown in Table 1.

[0073] Table 1. Particle size and stratification of nanoemulsions prepared in Examples 1-9 and Comparative Examples 1-24

[0074] Test Example 2 100 μL of methylene blue aqueous solution (1 mg / mL) and Sudan III solution (1 mg / mL, solvent: 95% ethanol) were added to 10 mL of the nanoemulsion prepared in Example 9, respectively. The dispersion of the two dyes was observed, and the results are as follows: Figure 1 As shown, the blank is the solution without dye. From Figure 1 As can be seen, methylene blue diffuses uniformly in the nanoemulsion, while Sudan III remains on the surface of the nanoemulsion, indicating that the nanoemulsion is an oil-in-water system.

[0075] Test Example 3 The nanoemulsion prepared in Example 9 was diluted 10, 100, and 1000 times with deionized water, respectively, and stored at room temperature for 10 days. The layering of the samples was observed at 1, 3, 5, 7, and 10 days. The results are as follows: Figure 2 As shown.

[0076] from Figure 2 As can be seen, the nanoemulsion did not separate into layers within 10 days after being diluted 10 times, 100 times, and 1000 times, indicating that the nanoemulsion system is stable.

[0077] Test Example 4 The particle size, polydispersity index, and zeta potential of the nanoemulsion prepared in Example 9 were tested using a nanoparticle size and zeta potential analyzer. The results are as follows: Figure 3 As shown, Figure 3 From left to right, the graphs show particle size, polydispersity index, and zeta potential. Figure 3 As can be seen, the nanoemulsion has a particle size of 129.63 nm, a polydispersity index of 0.296, and a zeta potential of 1.06.

[0078] Test Example 5 Plastic flowerpots with a diameter of 11.5 cm and a height of 11 cm were selected. Field soil and organic fertilizer were mixed evenly at a volume ratio of 3:1 and then filled into the flowerpots. Twenty uniform and plump jointed goatgrass seeds were selected and placed in a 5 cm × 5 cm nylon mesh bag. The mesh bag was then horizontally buried in the soil to a depth of 3 cm. Trans-2-hexenal (T2H) and the nanoemulsion (T2H-nm) prepared in Example 9 were injected into the soil using a sterile syringe to a depth of 3 cm. The volume ratio of trans-2-hexenal to soil in both the trans-2-hexenal and nanoemulsion was 76 μL / L. Sterile water treatment served as a blank control (CK). The flowerpots were placed in an artificial climate incubation chamber with the following conditions: day / night temperature 25℃ / 23℃ (light / dark), light cycle L / D = 12h / 12h, and light intensity 320 μmol·m⁻¹. -2 ·s -1 Water regularly to maintain soil moisture. After 7 days of cultivation, remove the mesh bags, count the number of germinated seeds, and calculate the germination rate. Each treatment was repeated three times. Germination rate (%) = number of germinated seeds per pot / total number of seeds per pot. Test results are as follows: Figure 4 As shown. From Figure 4 As can be seen from the data, when the application concentration was 76 μL / L, the germination rate of *Streptococcus senticosus* in the trans-2-hexenal nanoemulsion treatment group was significantly different from that in the trans-2-hexenal treatment group. P <0.01). The germination rate of *Gnaphalium affine* after treatment with trans-2-hexenal was 90.00%, while the germination rate after treatment with trans-2-hexenal nanoemulsion was 60.00%. This indicates that the inhibitory effect of trans-2-hexenal nanoemulsion on *Gnaphalium affine* germination is higher than that of trans-2-hexenal.

[0079] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A trans-2-hexenal oil-in-water nanoemulsion, characterized in that, It is prepared from the following raw materials: trans-2-hexenal, water, and emulsifier; The emulsifiers are Tween-80 and Span-80; the mass ratio of Tween-80 to Span-80 is 1:(5~9). The trans-2-hexenal oil-in-water nanoemulsion contains 0.9-25 wt% emulsifier and 0.2-50 wt% trans-2-hexenal.

2. The trans-2-hexenal oil-in-water nanoemulsion according to claim 1, characterized in that, The raw materials for the trans-2-hexenal oil-in-water nanoemulsion also include a co-emulsifier.

3. The trans-2-hexenal oil-in-water nanoemulsion according to claim 2, characterized in that, The emulsifier includes sodium alginate or chitosan.

4. The trans-2-hexenal oil-in-water nanoemulsion according to claim 3, characterized in that, When the co-emulsifier is sodium alginate, the content of sodium alginate in the trans-2-hexenal oil-in-water nanoemulsion is ≤0.05wt%.

5. The trans-2-hexenal oil-in-water nanoemulsion according to claim 3, characterized in that, When the co-emulsifier is chitosan, the chitosan content in the trans-2-hexenal oil-in-water nanoemulsion is ≥0.45wt%.

6. The trans-2-hexenal oil-in-water nanoemulsion according to claim 3, characterized in that, When the co-emulsifier is chitosan, the raw materials of the trans-2-hexenal oil-in-water nanoemulsion also include acetic acid.

7. The trans-2-hexenal oil-in-water nanoemulsion according to claim 6, characterized in that, The mass ratio of acetic acid to water is (0.01~0.1):

1.

8. The method for preparing trans-2-hexenal oil-in-water nanoemulsion according to any one of claims 1 to 7, characterized in that, include: Emulsifier, water and trans-2-hexenal were mixed and then subjected to shearing treatment to obtain trans-2-hexenal oil-in-water nanoemulsion; When the raw materials include a co-emulsifier and acetic acid, the emulsifier, water, trans-2-hexenal, co-emulsifier and acetic acid are mixed and then sheared to obtain trans-2-hexenal oil-in-water nanoemulsion.

9. The preparation method according to claim 8, characterized in that, The shearing rate is 4000~5000 rpm, and the shearing time is 4~10 min.

10. The application of the trans-2-hexenal water-in-oil nanoemulsion according to any one of claims 1 to 7 or the trans-2-hexenal water-in-oil nanoemulsion prepared by the preparation method according to claim 8 or 9 in inhibiting the germination of jointed goatgrass seeds.

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