Application of Oxytropis vulgaris as solvent and insecticide

Abstract

The present invention discloses the use of an Oxytropis flavescentis extract as a solubility aid for an organic solvent extract of Tungia cochinchinensis. The Oxytropis flavescentis extract is rich in active substances such as triterpenoid saponins and has good solubility aid for the organic solvent extract of Tungia cochinchinensis, thus solving the problem that the organic solvent extract of Tungia cochinchinensis is difficult to dissolve in water to a certain extent. Compared with Tween-80, the use of the Oxytropis flavescentis extract as a solubility aid is greener and healthier. The present invention also discloses the use of the Oxytropis flavescentis extract and the organic solvent extract of Tungia cochinchinensis as a pesticide.

Description

Technical Field

[0001] The invention relates to oxytropis flavescentis, and in particular to application of oxytropis flavescentis as a cosolvent and insecticide. Background Art

[0002] Oxytropis ochrocephala Bunge, commonly known as "Tuanba grass" and "horse intestine," is widely distributed in western my country and is one of the most serious noxious weeds that harms natural grasslands there. Oxytropis ochrocephala Bunge contains a variety of active ingredients, such as alkaloids, flavonoids, and triterpenoid saponins, making it of great research value. Its strong adaptability in the wild has made it a dominant species in the region, with a distribution area exceeding 3 million hectares. Its abundant reserves provide a material foundation for further research.

[0003] Clerodendrum japonicum, commonly known as Dragon Boat Flower and Champion Red, is a shrub of the genus Clerodendrum in the Verbenaceae family. It is primarily distributed in Guizhou, Yunnan, and Hunan provinces of my country. As a traditional Chinese medicinal herb, it not only possesses a wide range of medicinal benefits, such as dispelling wind and dampness, dispersing blood stasis and swelling, and clearing heat and detoxifying, but has also attracted considerable attention for its use as a biopesticide. Tian Wen et al. discovered that certain compounds in a petroleum ether extract of Clerodendrum japonicum, such as methyl palmitate, linalool, and hexahydrofarnesylacetone, exhibited excellent insecticidal activity. The extract exhibited strong insecticidal activity against the larvae of the moth (Spodoptera litura), with an LC50 of 12.534 mg / mL. With increasing awareness of food safety and environmental protection, the use of traditional chemical pesticides has come under increasing scrutiny. Clerodendrum japonicum extract, as a natural, low-toxic, and highly effective biopesticide resource, holds broad application prospects. It can not only effectively prevent and control insect pests on crops, reduce the use of chemical pesticides, and reduce the harm of pesticide residues to the environment and human body, but also promote the sustainable development of agriculture.

[0004] Over 30 compounds have been isolated and identified from Tung Blossom. Research on Tung Blossom compounds has primarily focused on moderately polar and water-soluble components, with relatively little research on the less polar petroleum ether fraction. Furthermore, the solubility of Tung Blossom petroleum ether extracts in water is low, making it difficult to adjust the concentration of the solution and its stability during long-term storage unsatisfactory, making it quite inconvenient to use. Research on the n-butanol extract of Tung Blossom is limited, and its insecticidal activity requires further investigation. Summary of the Invention

[0005] In view of this, one of the objects of the present invention is to provide an Oxytropis vulgaris as a cosolvent to solve the technical problem of low solubility of the organic solvent extract of Tung chinensis in water; the second object of the present invention is to provide an application of Oxytropis vulgaris as an insecticide to improve the insecticidal activity of the organic solvent extract of Tung chinensis.

[0006] One of the objectives of the present invention is achieved through the following technical solutions:

[0007] Application of Oxytropis flavescentis extract as a cosolvent for organic solvent extract of Tung chinensis.

[0008] Furthermore, the Oxytropis flavescentis extract is the total extract of Oxytropis flavescentis.

[0009] Furthermore, the preparation method of the total extract of Oxytropis vulgaris is as follows: mixing Oxytropis vulgaris and a hydrochloric acid aqueous solution with a pH value of 2.51 at a material-liquid ratio of 28-31:1, reflux extraction for 80-100 minutes at a temperature of 80-100°C, filtering the extract while hot to obtain a filtrate, repeating the reflux extraction and filtration multiple times, combining the filtrate and drying to obtain the total extract of Oxytropis vulgaris.

[0010] Furthermore, the organic solvent extract of Tungjae is Tungjae petroleum ether extract or Tungjae n-butanol extract.

[0011] Further, the following steps are included:

[0012] The Oxytropis flavescentis extract and ultrapure water are mixed to obtain an Oxytropis flavescentis extract aqueous solution; and the Oxytropis flavescentis extract aqueous solution is mixed with the Tungia chinensis organic solvent extract.

[0013] Furthermore, the Oxytropis flavescentis extract is the total extract of Oxytropis flavescentis.

[0014] Furthermore, the preparation method of the total extract of Oxytropis vulgaris is as follows: mixing Oxytropis vulgaris and a hydrochloric acid aqueous solution with a pH value of 2.51 at a material-liquid ratio of 28-31:1, reflux extraction for 80-100 minutes at a temperature of 80-100°C, filtering the extract while hot to obtain a filtrate, repeating the reflux extraction and filtration multiple times, combining the filtrate and drying to obtain the total extract of Oxytropis vulgaris.

[0015] Furthermore, the concentration of the aqueous solution of Oxytropis flavescentis extract is 17.65 mg / mL.

[0016] Furthermore, the organic solvent extract of Tungjae is Tungjae petroleum ether extract or Tungjae n-butanol extract.

[0017] Furthermore, the aqueous solution of the Oxytropis flavescentis extract is 200-250 mL, and the petroleum ether extract of the Tungjae Herba is 1 g.

[0018] Furthermore, the aqueous solution of the Oxytropis flavescentis extract is 30-60 mL, and the n-butanol extract of the Tungia chinensis is 1 g.

[0019] The second object of the present invention is achieved through the following technical solutions:

[0020] Application of Oxytropis flavescentis extract and Tungjae chinensis organic solvent extract as insecticide.

[0021] Furthermore, the method for mixing the Oxytropis flavescentis extract with the Thunb. chinensis organic solvent extract comprises the following steps:

[0022] The Oxytropis flavescentis extract and ultrapure water are mixed to obtain an Oxytropis flavescentis extract aqueous solution; and the Oxytropis flavescentis extract aqueous solution is mixed with the Tungia chinensis organic solvent extract.

[0023] Furthermore, the Oxytropis flavescentis extract is the total extract of Oxytropis flavescentis.

[0024] Furthermore, the preparation method of the total extract of Oxytropis vulgaris is as follows: mixing Oxytropis vulgaris and a hydrochloric acid aqueous solution with a pH value of 2.51 at a material-liquid ratio of 28-31:1, reflux extraction for 80-100 minutes at a temperature of 80-100°C, filtering the extract while hot to obtain a filtrate, repeating the reflux extraction and filtration multiple times, combining the filtrate and drying to obtain the total extract of Oxytropis vulgaris.

[0025] Furthermore, the concentration of the aqueous solution of Oxytropis flavescentis extract is 0.3-6 mg / mL, and the amount is 30 mL.

[0026] Furthermore, the Tung oil tree organic solvent extract is Tung oil tree petroleum ether extract or Tung oil tree n-butanol extract.

[0027] Furthermore, the amount of the Tungjae Tung petroleum ether extract or the Tungjae Tung n-butanol extract is 15 mg respectively.

[0028] The beneficial effects of the present invention are:

[0029] The invention discloses an application of the Oxytropis vulgaris as a cosolvent. The Oxytropis vulgaris contains rich active substances such as triterpenoid saponins, has good solubility for the Tungia oxyphylla organic solvent extract, and solves the problem that the Tungia oxyphylla organic solvent extract is difficult to dissolve in water to a certain extent. Compared with Tween-80, the use of the Oxytropis vulgaris extract as a cosolvent is greener and healthier.

[0030] During the preparation of the total extract of Oxytropis vulgaris, a small amount of hydrochloric acid is used to adjust the pH value of water, thereby reducing the amount of organic solvent used in the preparation, thereby saving costs and improving the safety of the preparation.

[0031] When the concentration of the total extract of Oxytropis flavescentis in aqueous solution was 17.65 mg / mL, the maximum solubility of the petroleum ether extract and the n-butanol extract of Thunbergia paniculata were 4.12 mg / mL and 19.61 mg / mL, respectively.

[0032] The present invention discloses an application of Oxytropis flavescentis as an insecticide. When the total extract of Oxytropis flavescentis and the organic solvent extract of Thunbergia oxyphylla are paired at certain concentrations, the LC50 values ​​against 3-day-old Spodoptera litura larvae are 1.081 mg / mL and 1.324 mg / mL, respectively. This is greatly improved compared with the insecticidal effect of a single extract. For example, the LC50 value of Thunbergia oxyphylla petroleum ether extract against Spodoptera litura is only 12.534 mg / mL, indicating that the insecticidal activity of the two is enhanced after pairing.

[0033] Other advantages, objectives, and features of the present invention will be described in part in the following description and, in part, will be apparent to those skilled in the art upon examination of the following description or may be learned from practice of the present invention. The objectives and other advantages of the present invention may be realized and obtained through the following description and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below with reference to the accompanying drawings, in which:

[0035] Figure 1 This is a graph showing the relationship between the logarithmic units of the activity of the Oxytropis flavescens and the petroleum ether extracts of Thunbergia oxyphylla against Spodoptera litura larvae at different concentrations and the probability values ​​in Example 3 of the present invention.

[0036] Figure 2 This is a graph showing the relationship between the logarithmic units of the activity of the combination of Oxytropis flavosum and the n-butanol extract of Thunbergia rubra against Spodoptera litura larvae at different concentrations and the probability values ​​in Example 3 of the present invention. DETAILED DESCRIPTION

[0037] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the preferred embodiments are only for illustrating the present invention, and are not intended to limit the scope of protection of the present invention.

[0038] The Oxytropis japonicum plant involved in this invention was collected from natural grasslands in Huangzhong County, Qinghai Province in September 2022 and identified as Oxytropis japonicum by Professor Mo Chonghui of Qinghai University. The plant is numbered (Tancj202209) and stored in the Natural Medicinal Chemistry Laboratory of the School of Ethnic Medicine, Guizhou University for Nationalities. The Spodoptera litura eggs used for testing were purchased from Jiyuan Keyun Biological Co., Ltd. They were reared on cabbage at a constant indoor temperature of (27±2)°C, with relative humidity controlled between 40% and 60%. After hatching, healthy third-instar larvae of uniform size were selected for testing. The Clerodendrum japonicum plant was collected from Dushan County, Guizhou Province, and identified as Clerodendrum japonicum, a plant of the genus Verbenaceae, by Kunming Zhifen Biotechnology Co., Ltd. Wax leaf specimens are stored in the Natural Medicinal Chemistry Laboratory of the School of Ethnic Medicine, Guizhou University for Nationalities (specimen number: KMZFC201907082).

[0039] Example 1

[0040] Application of Oxytropis flavescentis extract as a cosolvent for organic solvent extract of Tung chinensis.

[0041] First, extract the total extract of Oxytropis vulgaris:

[0042] Weigh 150 g of the whole plant of Oxytropis vulgaris at full flowering stage of 80 mesh and add it to a 1 L round-bottom flask. Add hydrochloric acid aqueous solution with a pH value of 2.51 to the round-bottom flask. The solid-liquid ratio of Oxytropis vulgaris to hydrochloric acid aqueous solution is 29.5 mL / g. Place the round-bottom flask in a 90 ° C water bath for reflux extraction for 87.5 min. Filter the extract while hot to obtain a filtrate. Repeat the reflux extraction and filtration twice. After combining the filtrates, dry them on a rotary evaporator to obtain the total extract of Oxytropis vulgaris. After measurement, 46.49 g of the total extract of Oxytropis vulgaris was obtained, and the extraction rate P of the total extract of Oxytropis vulgaris was calculated according to the following formula:

[0043]

[0044] Where:

[0045] P is the extraction rate of total extract of Oxytropis flavescentis (%);

[0046] M1 is the total extract mass of Oxytropis flavescentis (g);

[0047] M2 is the total mass of Oxytropis vulgaris (g).

[0048] The total extraction rate of Oxytropis vulgaris extract was calculated to be 31%.

[0049] Then, the solubility of the total extract of Oxytropis vulgaris in water was measured:

[0050] 3 g of total extract of Oxytropis vulgaris was placed in a 250 mL beaker. Ultrapure water was added to the beaker several times at room temperature and stirred. When the volume of ultrapure water was 170 mL, there was no suspended matter in the solution, indicating that the total extract of Oxytropis vulgaris had been completely dissolved in the ultrapure water and reached a saturated state. At this time, the maximum solubility of the total extract of Oxytropis vulgaris in ultrapure water was measured to be 17.65 mg / mL. The solubility measurement results of the total extract of Oxytropis vulgaris are shown in Table 1:

[0051] Table 1 Solubility measurement results of total extract of Oxytropis vulgaris

[0052]

[0053] Finally, the solubilizing effect of the total extract of Oxytropis flavosum on the petroleum ether extract of Tung tung was measured:

[0054] 1 g of the petroleum ether extract of Tung tung was placed in a 250 mL beaker, and 243 mL of an aqueous solution of total extract of Oxytropis flavescentis with a concentration of 17.65 mg / mL was gradually added to the beaker at room temperature and stirred thoroughly until the petroleum ether extract of Tung tung was fully dissolved, and there was no suspended matter in the solution, reaching a saturated state. At this time, the maximum solubility of the petroleum ether extract of Tung tung was measured to be 4.12 mg / mL. The solubility measurement results of the petroleum ether extract of Tung tung when the total extract of Oxytropis flavescentis was used as the solubilizer are shown in Table 2:

[0055] Table 2 Solubility measurement results of the Tung oil extract when the total extract of Oxytropis chinensis was dissolved

[0056]

[0057] Example 2

[0058] Application of Oxytropis flavescentis extract as a cosolvent for n-butanol extract of Thunbergia paniculata.

[0059] First, extract the total extract of Oxytropis vulgaris:

[0060] 150 g of the whole plant of Oxytropis vulgaris in full flowering stage with an 80-mesh diameter was weighed and added to a 1 L round-bottom flask. A hydrochloric acid aqueous solution with a pH value of 2.51 was added to the round-bottom flask. The solid-liquid ratio of Oxytropis vulgaris to the hydrochloric acid aqueous solution was 28 mL / g. The round-bottom flask was placed in a 100° C. water bath and refluxed for 80 min. The extract was filtered while hot to obtain a filtrate. The reflux extraction and filtration were repeated twice. The filtrates were combined and dried on a rotary evaporator to obtain the total extract of Oxytropis vulgaris.

[0061] Then, the solubility of the total extract of Oxytropis vulgaris in water was measured:

[0062] 3 g of total extract of Oxytropis vulgaris was placed in a 250 mL beaker. Ultrapure water was added to the beaker several times at room temperature and stirred. When the volume of ultrapure water was 170 mL, there was no suspended matter in the solution, indicating that the total extract of Oxytropis vulgaris had been completely dissolved in the ultrapure water and reached a saturated state. At this time, the maximum solubility of the total extract of Oxytropis vulgaris in ultrapure water was measured to be 17.65 mg / mL. The solubility measurement results of the total extract of Oxytropis vulgaris are shown in Table 1:

[0063] Table 1 Solubility measurement results of total extract of Oxytropis vulgaris

[0064]

[0065] Finally, the solubility-enhancing effect of the total extract of Oxytropis flavosum on the n-butanol extract of Tung chinensis was measured:

[0066] 1 g of the n-butanol extract of Tung Tung was placed in a 250 mL beaker, and 51 mL of an aqueous solution of total extract of Oxytropis flavescentis with a concentration of 17.65 mg / mL was gradually added to the beaker at room temperature and stirred thoroughly until the n-butanol extract of Tung Tung was fully dissolved and no suspended matter was present in the solution, reaching a saturated state. At this time, the maximum solubility of the n-butanol extract of Tung Tung was measured to be 19.61 mg / mL. The solubility measurement results of the n-butanol extract of Tung Tung when the total extract of Oxytropis flavescentis was used as the solubility aid are shown in Table 3:

[0067] Table 3 Solubility measurement results of the n-butanol extract of Tung chinensis when the total extract of Oxytropis chinensis was solubilized

[0068]

[0069] Example 3

[0070] Application of Oxytropis flavescentis extract and Tungjae chinensis petroleum ether extract as insecticides.

[0071] First, extract the total extract of Oxytropis vulgaris:

[0072] 150 g of the whole plant of Oxytropis vulgaris in full flowering stage with an 80-mesh diameter was weighed and added to a 1 L round-bottom flask. A hydrochloric acid aqueous solution with a pH value of 2.51 was added to the round-bottom flask. The solid-liquid ratio of Oxytropis vulgaris to the hydrochloric acid aqueous solution was 31 mL / g. The round-bottom flask was placed in an 80° C. water bath and refluxed for 100 min. The extract was filtered while hot to obtain a filtrate. The reflux extraction and filtration were repeated twice. The filtrates were combined and dried on a rotary evaporator to obtain the total extract of Oxytropis vulgaris.

[0073] Then, the activity of the total extract of Oxytropis flavescentis against Spodoptera litura was tested:

[0074] The insecticidal activity of Oxytropis flavonoids total extract against Spodoptera litura was tested using the insect and leaf immersion method. 180 mg of Oxytropis flavonoids total extract was weighed and added to 30 mL of ultrapure water to prepare a 6 mg / mL aqueous solution. Ninety healthy, uniformly sized, third-instar S. litura were grouped together. A hydrochloric acid solution with a pH of 2.51 was used as a control. Larval mortality was defined as the absence of a noticeable spontaneous reaction to light touch after the insects were shrunken. Larval mortality was recorded at 24, 48, and 72 hours.

[0075] Since the mortality rate of the control group is between 5% and 20%, the mortality rate needs to be corrected. The mortality rate and the corrected mortality rate are calculated according to the following formula based on the test results.

[0076]

[0077] The results of the activity of the total extract of Oxytropis flavonoides against the larvae of Spodoptera litura are shown in Table 4.

[0078] Table 4 Activity of total extract of Oxytropis flavosum against larvae of Spodoptera litura

[0079]

[0080] The table above shows that the adjusted mortality rate increased with time, with the highest adjusted mortality rate at 23.4% after immersion in the insect extract for 72 hours.

[0081] Finally, five portions of Oxytropis flavescentis total extract were weighed and added to 30 mL of ultrapure water to prepare aqueous solutions of Oxytropis flavescentis at concentrations of 0.375, 0.75, 1.5, 3, and 6 mg / mL, respectively. 15 mg of the petroleum ether extract of Thunbergia ternata was added to each concentration of the Oxytropis flavescentis solution. Ninety healthy, uniformly sized, third-instar Spodoptera litura were grouped together, and a hydrochloric acid solution with a pH of 2.51 was used as a control. The mortality criterion was that the insects shrivelled and showed no obvious spontaneous reaction to light touch. The number of larvae that died after 24, 48, and 72 hours was recorded.

[0082] Since the mortality rate of the control group is between 5% and 20%, the mortality rate needs to be corrected. The mortality rate and the corrected mortality rate are calculated according to the following formula based on the test results.

[0083]

[0084] The mutual activity of the total extract of Oxytropis vulgaris and the petroleum ether extract of Thunbergia paniculata against Spodoptera litura larvae is shown in Table 5:

[0085] Table 5 The mutual activity of the total extract of Oxytropis flavosum and the petroleum ether extract of Thunbergia oxyphylla against the larvae of Spodoptera litura

[0086]

[0087] The data showed a positive correlation between immersion time and corrected mortality, with longer immersion times associated with higher corrected mortality. Furthermore, the corrected mortality trended upward with increasing concentration. The highest insecticidal activity was observed at a concentration of 6 mg / mL, with a corrected mortality rate of 57.7% for the 72-hour extract of the petroleum ether of the Tung tung oil plant. This significantly increased the corrected mortality rate over 72 hours compared to a 6 mg / mL total extract of Oxytropis flavescentis, indicating that adding a certain amount of the active fraction extract of the Tung tung oil plant to the same concentration of the total extract of Oxytropis flavescentis can enhance insecticidal activity.

[0088] Determination of the median lethal concentration after mixing Oxytropis vulgaris and Tungia oxyphylla petroleum ether extracts:

[0089] SPSS 20.0 software was used for data statistical analysis to calculate the median lethal concentration (LC50) value and 95% confidence limit.

[0090] The logarithm of different total alkaloid concentrations is used as the horizontal axis, and the corrected mortality rate is converted into probability value as the vertical axis. Figure 1As shown, the probability unit model equation for the Tung oil ether extract was: P = 0.21362x - 0.4924 (R² = 0.999). Finally, the LC50 of the Tung oil ether extract against 3-day-old larvae of Spodoptera litura was determined to be 1.081 mg / mL, with a 95% confidence interval of 0.523-1.795. This significantly improved the LC50 of the Tung oil ether extract alone against Spodoptera litura (12.534 mg / mL). This further demonstrates that combining the total extract of Oxytropis flavosum with the Tung oil ether extract can enhance insecticidal activity.

[0091] Example 4

[0092] Application of Oxytropis flavescentis extract and Tungjae chinensis n-butanol extract as insecticides.

[0093] First, extract the total extract of Oxytropis vulgaris:

[0094] 150 g of the whole plant of Oxytropis vulgaris in full flowering stage at 80 mesh was weighed and added to a 1 L round-bottom flask, and a hydrochloric acid aqueous solution with a pH value of 2.51 was added to the round-bottom flask, and the solid-liquid ratio of Oxytropis vulgaris to the hydrochloric acid aqueous solution was 28.6 mL / g. The round-bottom flask was placed in an 85° C. water bath and refluxed for 95 min. The extract was filtered while hot to obtain a filtrate. The reflux extraction and filtration were repeated twice, and the combined filtrate was dried on a rotary evaporator to obtain the total extract of Oxytropis vulgaris.

[0095] Then, the activity of the total extract of Oxytropis flavescentis against Spodoptera litura was tested:

[0096] The insecticidal activity of Oxytropis flavescentis total extract against Spodoptera litura was tested using the insect and leaf immersion method. 180 mg of Oxytropis flavescentis total extract was weighed and added to 30 mL of ultrapure water to prepare a 6 mg / mL aqueous solution. Ninety healthy, uniformly sized, third-instar S. litura were grouped together. A hydrochloric acid solution with a pH of 2.51 was used as a control. Larval mortality was defined as the absence of a noticeable spontaneous reaction to light touch when the insect body shrivelled. Larval mortality was recorded at 24, 48, and 72 hours.

[0097] Since the mortality rate of the control group is between 5% and 20%, the mortality rate needs to be corrected. The mortality rate and the corrected mortality rate are calculated according to the following formula based on the test results.

[0098]

[0099] The results of the activity of the total extract of Oxytropis flavonoides against the larvae of Spodoptera litura are shown in Table 4.

[0100] Table 4 Results of the activity of the total extract of Oxytropis flavophylla against Spodoptera litura larvae

[0101]

[0102] The table above shows that the adjusted mortality rate increased with time, with the highest adjusted mortality rate at 23.4% after immersion in the insect extract for 72 hours.

[0103] Finally, five portions of Oxytropis flavescentis total extract were weighed and added to 30 mL of ultrapure water to prepare aqueous solutions of Oxytropis flavescentis at concentrations of 0.375, 0.75, 1.5, 3, and 6 mg / mL, respectively. 15 mg of the n-butanol extract of Thunbergia chinensis was added to each concentration of the Oxytropis flavescentis solution. Ninety healthy, uniformly sized, third-instar Spodoptera litura were grouped together, and a hydrochloric acid solution with a pH of 2.51 was used as a control. The criterion for mortality was the absence of a noticeable spontaneous reaction to light touch when the insects shrivelled. Larval mortality was recorded at 24, 48, and 72 hours.

[0104] Since the mortality rate of the control group is between 5% and 20%, the mortality rate needs to be corrected. The mortality rate and the corrected mortality rate are calculated according to the following formula based on the test results.

[0105]

[0106] The results of the mutual activity of the total extract of Oxytropis chrysantha and the n-butanol extract of Tungia chinensis against the larvae of Spodoptera litura are shown in Table 6: Table 6 The results of the mutual activity of the total extract of Oxytropis chrysantha and the n-butanol extract of Tungia chinensis against the larvae of Spodoptera litura

[0107]

[0108] The data showed a positive correlation between immersion time and corrected mortality, with longer immersion times associated with higher corrected mortality. Furthermore, the corrected mortality trended upward with increasing concentration. The highest insecticidal activity was observed at a concentration of 6 mg / mL, with a corrected mortality rate of 61.6% for the n-butanol extract of the Chinese tung tree. This significantly increased the corrected mortality rate over 72 hours compared to a 6 mg / mL total extract of Oxytropis flavescentis, indicating that adding a certain amount of an extract of the active fraction of the Chinese tung tree to a solution of the same total extract concentration can enhance insecticidal activity.

[0109] Determination of median lethal concentration after mixing Oxytropis vulgaris and Tungia oxyphylla n-butanol extracts:

[0110] SPSS 20.0 software was used for data statistical analysis to calculate the median lethal concentration (LC50) value and 95% confidence limit.

[0111] The logarithm of different total alkaloid concentrations was used as the horizontal axis, and the corrected mortality rate was converted into probability values ​​as the vertical axis, such as Figure 2As shown, the probability unit model equation for the n-butanol extract of Tung tung was: P = 0.47129x - 0.2495 (R2 = 0.999). Finally, the LC50 of the n-butanol extract of Tung tung against 3-day-old larvae of Spodoptera litura was determined to be 1.324 mg / mL, with a 95% confidence interval of 0.792-2.091. This is significantly higher than the LC50 of the single n-butanol extract of Tung tung against Spodoptera litura (20.72 mg / mL). This further demonstrates that combining the total extract of Oxytropis flavosum with the organic solvent extract of Tung tung can enhance the insecticidal activity.

[0112] Using an aqueous solution of 17.65 mg / mL of Oxytropis chinensis total extract to dissolve the active fraction of Tungia chinensis, the maximum solubilities of the Tungia chinensis petroleum ether extract and the n-butanol extract were 4.12 mg / mL and 19.61 mg / mL, respectively. This indicates that some active substances in the Oxytropis chinensis total extract have a strong solubility effect on the active fraction of Tungia chinensis, addressing, to some extent, the insolubility problem of the active fraction of Tungia chinensis. Furthermore, when the Oxytropis chinensis total extract and the Tungia chinensis organic solvent extract were cross-matched at specific concentrations, the LC50 values ​​against three-day-old Spodoptera litura larvae were 1.081 mg / mL and 1.324 mg / mL, respectively. This significantly improved the insecticidal effect compared to either extract alone, indicating that the insecticidal activity of the two extracts was enhanced. In this experiment, using Oxytropis chinensis total extract as a cosolvent is more environmentally friendly and healthier than using Tween-80. Using a small amount of hydrochloric acid to adjust the pH of the water during the extraction process reduces the amount of organic solvents used, saving costs while improving experimental safety. This further broadens the use of Oxytropis vulgaris and provides a scientific basis for the development of new green pesticides.

[0113] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not limiting. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solutions, which should all be included in the scope of the claims of the present invention.

Claims

1. Application of Oxytropis vulgaris extract as a cosolvent for organic solvent extract of Tung chinensis; in, The method of using an Oxytropis flavescentis extract to dissolve an organic solvent extract of Tung chinensis comprises the following steps: The Oxytropis flavescentis extract and ultrapure water are mixed to obtain an Oxytropis flavescentis extract aqueous solution; the Oxytropis flavescentis extract aqueous solution is mixed with the Tungia chinensis organic solvent extract; The Oxytropis vulgaris extract is an Oxytropis vulgaris total extract. The preparation method of the Oxytropis vulgaris total extract comprises the following steps: mixing Oxytropis vulgaris and a hydrochloric acid aqueous solution with a pH value of 2.51 at a material-liquid ratio of 28-31:1, performing reflux extraction for 80-100 minutes at a temperature of 80-100° C., filtering the extract while hot to obtain a filtrate, repeating the reflux extraction and filtration multiple times, combining the filtrates, and drying to obtain the Oxytropis vulgaris total extract. The concentration of the aqueous solution of the Oxytropis vulgaris extract is 17.65 mg / mL; the organic solvent extract of the Atractylodes lancea is a petroleum ether extract of the Atractylodes lancea or a n-butanol extract of the Atractylodes lancea; when the organic solvent extract of the Atractylodes lancea is a petroleum ether extract of the Atractylodes lancea, the aqueous solution of the Oxytropis vulgaris extract is 200-250 mL, and the petroleum ether extract of the Atractylodes lancea is 1 g; when the organic solvent extract of the Atractylodes lancea is a n-butanol extract of the Atractylodes lancea, the aqueous solution of the Oxytropis vulgaris extract is 30-60 mL, and the n-butanol extract of the Atractylodes lancea is 1 g.

2. Application of Oxytropis vulgaris extract and Tungia oxyphylla organic solvent extract as insecticides; in, The method for mixing an Oxytropis flavescentis extract with an organic solvent extract of Tungjae cochinchinensis comprises the following steps: The Oxytropis flavescentis extract and ultrapure water are mixed to obtain an Oxytropis flavescentis extract aqueous solution; the Oxytropis flavescentis extract aqueous solution is mixed with the Tungia chinensis organic solvent extract; The Oxytropis vulgaris extract is an Oxytropis vulgaris total extract. The preparation method of the Oxytropis vulgaris total extract comprises the following steps: mixing Oxytropis vulgaris and a hydrochloric acid aqueous solution with a pH value of 2.51 at a material-liquid ratio of 28-31:1, performing reflux extraction for 80-100 minutes at a temperature of 80-100° C., filtering the extract while hot to obtain a filtrate, repeating the reflux extraction and filtration multiple times, combining the filtrates, and drying to obtain the Oxytropis vulgaris total extract. The concentration of the aqueous solution of the Oxytropis flavescentis extract is 0.3-6 mg / mL, and the amount is 30 mL; the organic solvent extract of the Tungia oxyphylla is a petroleum ether extract or a n-butanol extract of the Tungia oxyphylla; the petroleum ether extract or the n-butanol extract of the Tungia oxyphylla are 15 mg respectively.

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