A method for increasing the nervonic acid content in Acer truncatum bunge seed oil

Abstract

The application discloses a method for improving the content of nervonic acid in Acer truncatum seed oil and belongs to the technical field of plant quality improvement and synergistic cultivation. The application sprays the leaf surface of Acer truncatum with a leaf fertilizer containing potassium dihydrogen phosphate. The application sprays the fast-growing period of Acer truncatum fruit growth and development with the leaf fertilizer of optimized proportion of potassium dihydrogen phosphate for multiple times. Through field tests and oil component analysis, it is found that the spraying of the leaf fertilizer can effectively promote the biosynthesis of unsaturated fatty acids in Acer truncatum seeds, in particular, the content of nervonic acid is obviously improved, and the composition ratio of unsaturated fatty acids such as alpha-linolenic acid and erucic acid is also obviously optimized, so that the quality of Acer truncatum oil is improved, and the method has important practical guiding value for promoting the efficient development and utilization of nervonic acid resources of Acer truncatum.

Description

Technical Field

[0001] This invention belongs to the field of plant quality improvement and efficiency enhancement cultivation technology, specifically relating to a method for increasing the nervonic acid content in Acer truncatum seed oil. Background Technology

[0002] As people pay increasing attention to the nutritional value of food, the content of unsaturated fatty acids has become an important standard for measuring the quality of healthy edible oils. Therefore, the content of unsaturated fatty acids directly affects the nutritional value and market competitiveness of Acer truncatum seed oil. Optimizing the composition of unsaturated fatty acids in Acer truncatum seed oil, especially increasing the content of nervonic acid, is of great significance for developing Acer truncatum brain health products and high-end functional edible oils.

[0003] Numerous studies both domestically and internationally have demonstrated that mineral nutrition supplementation plays a significant role in promoting high-quality and high-yield economic tree species. Appropriate application can regulate plant growth and development, which is beneficial for increasing the nutrient content of plant seeds and enhancing their economic value.

[0004] The seed traits of Acer truncatum are significantly influenced by the ecological environment, resulting in severe germplasm differentiation through long-term natural selection and species evolution. Differences exist in the characteristics, fatty acid composition ratios, and contents of seed oil, limiting the maximization of its economic value. Currently, there are few reports on increasing the nervonic acid content in Acer truncatum through exogenous intervention techniques; therefore, how to improve the fatty acid ratio in Acer truncatum seed oil, especially increasing the nervonic acid content, through exogenous intervention techniques has become a current research hotspot. Increasing the nervonic acid content in Acer truncatum seeds will be of great significance for the supply of nervonic acid raw materials needed for the prevention and treatment of brain diseases. Summary of the Invention

[0005] The technical problem to be solved by this invention is to provide a method for increasing the nervonic acid content in Acer truncatum seed oil. This method effectively promotes the biosynthesis of unsaturated fatty acids in Acer truncatum seeds and has important practical guiding value for promoting the efficient development and utilization of Acer truncatum nervonic acid resources.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0007] A method for increasing the nervonic acid content in Acer truncatum seed oil involves preparing a foliar fertilizer containing potassium dihydrogen phosphate and spraying it onto the leaves of Acer truncatum.

[0008] Furthermore, the Acer truncatum was selected from 10-year-old healthy plants.

[0009] Furthermore, the concentration of potassium dihydrogen phosphate is 1.5 g / L to 7.5 g / L.

[0010] Furthermore, the number of spraying applications is 1 to 3.

[0011] Furthermore, the spraying method is as follows: spray approximately 5L per tree evenly on the leaves of the Acer truncatum. The spraying period is from mid-June to mid-August, with the optimal spraying time being once in mid-June and once in mid-July, for a total of 2 sprays. If it rains, re-spray.

[0012] Furthermore, a solution containing 6.0 g / L potassium dihydrogen phosphate was prepared and sprayed onto the leaves of Acer truncatum once in mid-June and once in mid-July, for a total of two sprays.

[0013] A method to increase the oleic acid content in the seed oil of Acer truncatum involves spraying the leaves of Acer truncatum with potassium dihydrogen phosphate at a concentration of 1.5 g / L once each in mid-June, mid-July, and mid-August, for a total of three sprays.

[0014] A method for increasing the linoleic acid content in the seed oil of Acer truncatum involves spraying the leaves of Acer truncatum with potassium dihydrogen phosphate at a concentration of 7.5 g / L once each in mid-June, mid-July, and mid-August, for a total of three sprays.

[0015] A method for increasing the α-linolenic acid content in Acer truncatum seed oil, wherein potassium dihydrogen phosphate at a concentration of 4.5 g / L is sprayed onto the leaves of Acer truncatum once each in mid-June, mid-July, and mid-August, for a total of three sprays.

[0016] A method for increasing the γ-linolenic acid content in Acer truncatum seed oil, wherein potassium dihydrogen phosphate at a concentration of 4.5 g / L is sprayed onto the leaves of Acer truncatum once each in mid-June, mid-July, and mid-August, for a total of 3 sprays.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] (1) This invention involves spraying an optimized ratio of potassium dihydrogen phosphate foliar fertilizer multiple times during the rapid growth and development period of Acer truncatum fruit. Through field trials and oil composition analysis, it was found that the application of this foliar fertilizer can effectively promote the biosynthesis of unsaturated fatty acids in Acer truncatum seeds. The content of nervonic acid is particularly significantly increased to 8.04%. At the same time, the composition ratio of unsaturated fatty acids such as α-linolenic acid and erucic acid is also significantly optimized, thus improving the oil quality of Acer truncatum.

[0019] (2) The technical solution of the present invention is simple to operate and cost controllable. It provides important theoretical basis and technical support for the high-quality and efficient cultivation of Acer truncatum, an important woody oilseed tree species. It has important practical guiding value for promoting the efficient development and utilization of Acer truncatum nervonic acid resources. At the same time, it provides new research ideas for the quality regulation of woody oilseed crops. Attached Figure Description

[0020] Figure 1This is a gas chromatogram of the main fatty acid components of Acer truncatum seeds under different spraying treatments according to this application; in the figure, 1, palmitic acid; 2, heptadecanic acid; 3, stearic acid; 4, oleic acid; 5, linoleic acid; 6, α-linolenic acid; 7, γ-linolenic acid; 8, arachidonic acid; 9, erucic acid; 10, nervonic acid. Detailed Implementation

[0021] The present invention will be further illustrated below with reference to specific embodiments. These embodiments are implemented based on the technical solutions of the present invention, and it should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention.

[0022] The experimental site for this study was a maple forest in Yangcang Village, Tengzhou City, Shandong Province (117°15′E, 35°08′N). This region has a temperate monsoon continental climate with abundant sunshine and rainfall. The average annual temperature is 14.6℃, the average annual ground temperature is 16.3℃, the average annual precipitation is about 773.1 mm, the frost-free period is about 210 days, and the annual sunshine duration is 2383 hours.

[0023] The Acer truncatum used in the following examples came from the Acer truncatum experimental forest in Yangcang Village, Tengzhou City, Shandong Province. Ten-year-old healthy Acer truncatum Bunge trees with consistent site conditions, good growth, robust trees, no pests or diseases, and normal flowering and fruiting were selected as test trees. The average tree height was (6.5±0.5) m, the average diameter at breast height was (15.5±0.8) cm, the tree spacing was 8 m × 8 m, and the trees were managed in a conventional manner.

[0024] The potassium dihydrogen phosphate used in the following examples was purchased from "Guoguang Power Potassium" (KH2PO4≧98%, P2O5≧51%, K2O≧33.8%) produced by Sichuan Runer Technology Co., Ltd.; gibberellin was purchased from "Sanliu Brand" gibberellic acid (active ingredient content 75%) produced by Shanghai Tongrui Biotechnology Co., Ltd.; petroleum ether (analytical grade, boiling range 60-90℃) and methanol (HPLC) were purchased from Sinopharm Chemical Reagent Co., Ltd.; and sodium hydroxide (analytical grade) was purchased from Xilong Chemical Co., Ltd.

[0025] The following example describes the spraying method for Acer truncatum: Apply approximately 5L of the solution evenly to the leaves of each tree. Spraying should be done from mid-June to mid-August, with the optimal application times being once in mid-June and once in mid-July, for a total of two applications. Choose a sunny, windless day for spraying. If it rains after spraying, re-spraying is necessary.

[0026] Example 1

[0027] During the rapid growth period of Acer truncatum fruit development from June to August 2023, 10-year-old healthy plants from the Acer truncatum experimental forest in Yangcang Village were selected. Foliar spraying experiments with potassium dihydrogen phosphate and gibberellin were conducted monthly, with different numbers of applications each month, to screen for the optimal exogenous substances. The exogenous substances used were 3 g / L potassium dihydrogen phosphate aqueous solution and 50 mg / L GA3 aqueous solution, with three application frequencies: 1, 2, and 3 times. A control was established by spraying an equal volume of water. In early November 2023, when the Acer truncatum fruit matured, normally developed and intact winged fruits were collected. After removing the pericarp and seed coat, the fatty acid components of the Acer truncatum seeds were measured. The results are shown in Tables 1-2.

[0028] Test method for fatty acid components: Accurately weigh 1.5g of Acer truncatum seed kernel sample and grind it into a fine powder in a mortar. Quantitatively transfer the powder to a 10mL centrifuge tube, add 2mL of analytical grade petroleum ether (boiling range 60-90℃), and sonicate at 25℃ for 2h in a 40kHz ultrasonic cleaner. Then add 2mL of 0.4mol / L methanol-sodium hydroxide solution (preparation method: accurately weigh 1.6g of sodium hydroxide solid and dissolve it in 100mL of HPLC methanol), and sonicate for methyl esterification under the same conditions for 1h. After the reaction, add distilled water to a final volume of 10mL, vortex for 30s to mix thoroughly, and centrifuge at 5000r / min for 5min in a benchtop centrifuge. Collect the supernatant and transfer it to a brown sample vial for analysis. Fatty acid components were analyzed using a Shimadzu QP2010 ultra gas chromatograph-mass spectrometer equipped with a TR-WAXMS capillary column (30.00m×0.25mm×0.25μm). High-purity helium was used as the carrier gas in constant flow mode (1.0 mL / min, split ratio 10). The temperature program was as follows: initial temperature 80℃, held for 2.5 min, increased to 210℃ at 15℃ / min, then increased to 230℃ at 2℃ / min, held for 10 min. The injection port temperature was 200℃. Qualitative analysis was performed by comparison with known fatty acid methyl ester standards. Quantitative analysis used the peak area normalization method to calculate the relative content of each fatty acid, such as... Figure 1 As shown.

[0029] Table 1. Effects of different types of exogenous substances sprayed on the content of saturated fatty acid components in Acer truncatum seeds in 2023

[0030]

[0031]

[0032] Table 2. Effects of different types of exogenous substances sprayed on the content of unsaturated fatty acid components in Acer truncatum seeds in 2023

[0033]

[0034] The results in Tables 1 and 2 show that the application of potassium dihydrogen phosphate and gibberellin had varying degrees of influence on the content of saturated and unsaturated fatty acid components in Acer truncatum seeds. In comparison, potassium dihydrogen phosphate was more beneficial in increasing the content of unsaturated fatty acid components in the seeds. In the T1 treatment, which was sprayed once with 3 g / L potassium dihydrogen phosphate, the content of unsaturated fatty acids such as α-linolenic acid, γ-linolenic acid, erucic acid, and nervonic acid in Acer truncatum seeds reached a relatively high level. Therefore, potassium dihydrogen phosphate mixed aqueous solution was selected as the best exogenous substance for increasing the nervonic acid content in Acer truncatum seeds and improving the quality of its seed oil.

[0035] Example 2

[0036] Based on the foliar spraying experiment results of 2023, during the rapid growth period of Acer truncatum fruit development from June to August 2024, 10-year-old healthy plants from the Acer truncatum experimental forest in Yangcang Village were selected. Foliar spraying experiments were conducted monthly with different concentrations (1.5–7.5 g / L) and frequency of potassium dihydrogen phosphate, with one spray per month to determine the optimal concentration and frequency of potassium dihydrogen phosphate spraying. Three spraying frequencies were set: one, two, and three times, with an equal volume of water sprayed as a control. In early November 2024, when the Acer truncatum fruit was ripe, normally developed and intact winged fruits were collected. After removing the pericarp and seed coat, the content of various fatty acid components in the Acer truncatum seeds was measured. The results are shown in Tables 3-4.

[0037] Test Method: In early November 2024 (fruit ripening period), several normally developed winged fruits were collected from the east, south, west, and north directions of the tested Acer truncatum trees. These were placed in labeled mesh bags, brought back to the laboratory, and dried for later use. For each treatment, several Acer truncatum kernels (with the pericarp and seed coat removed) were randomly selected for determination of their fatty acid composition. The specific testing methods for each fatty acid composition were the same as in Example 1.

[0038] Table 3. Effects of different concentrations and frequency of potassium dihydrogen phosphate spraying on the content of saturated fatty acid components in Acer truncatum seeds in 2024.

[0039]

[0040]

[0041] Table 4. Effects of different concentrations and frequency of potassium dihydrogen phosphate spraying on the content of unsaturated fatty acid components in Acer truncatum seeds in 2024.

[0042]

[0043]

[0044]

[0045] As shown in Tables 3 and 4, the contents of four fatty acids (heptadecanoic acid, stearic acid, arachidic acid, and erucic acid) were basically consistent among different treatment groups for the content of each fatty acid component in Acer truncatum seeds; however, the contents of the other six fatty acids (palmitic acid, oleic acid, linoleic acid, α-linolenic acid, γ-linolenic acid, and nervonic acid) showed significant differences, indicating that the application of potassium dihydrogen phosphate could cause significant changes in their contents, but the effects of increasing or decreasing were different.

[0046] The results of the analysis of unsaturated fatty acid content in Acer truncatum seeds showed that the A3 treatment (1.5 g / L potassium dihydrogen phosphate sprayed three times) achieved the highest oleic acid content, significantly higher than the control group by 1.5%. The E3 treatment (7.5 g / L potassium dihydrogen phosphate sprayed three times) achieved the highest linoleic acid content, followed by the 3.0 g / L potassium dihydrogen phosphate sprayed twice. The α-linolenic acid content reached high levels when sprayed three times with 4.5 g / L, 6.0 g / L, or 7.5 g / L potassium dihydrogen phosphate, significantly higher than the control group by 0.38%, 0.33%, and 0.30%, respectively. The D1, D3, E2, and E3 treatments showed relatively high γ-linolenic acid content, significantly higher than the control. Regarding nervonic acid content, except for spraying with 1.5 g / L potassium dihydrogen phosphate 2 or 3 times or 7.5 g / L potassium dihydrogen phosphate 3 times, which resulted in a slight increase in nervonic acid content but not a significant effect due to insufficient or excessive intensity, all other spraying treatments significantly increased the nervonic acid content in Acer truncatum seed oil. This shows that appropriate concentrations and frequency of potassium dihydrogen phosphate spraying have a very significant positive promoting effect on increasing nervonic acid content. Among them, the D2 treatment, i.e., spraying with 6.0 g / L potassium dihydrogen phosphate 2 times, achieved the highest nervonic acid content of 8.04%, which was 2.14% higher than the control group. The C3 and B2 treatments were the next most effective, with nervonic acid contents of 7.80% and 7.49%, respectively, which were 1.90% and 1.59% higher than the control group, respectively.

[0047] 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 method for increasing the nervonic acid content in Acer truncatum seed oil, characterized in that, Prepare a solution containing 6.0 g / L potassium dihydrogen phosphate and apply it evenly to the leaves of the Acer truncatum tree at a dosage of 5 L per tree each time. Spray once in mid-June and once in mid-July, for a total of 2 sprays. If it rains, re-spray.

2. The method for increasing the nervonic acid content in Acer truncatum seed oil according to claim 1, characterized in that: The Acer truncatum was selected from healthy 10-year-old plants.

3. A method for increasing the linoleic acid content in Acer truncatum seed oil, characterized in that: Apply potassium dihydrogen phosphate at a concentration of 7.5 g / L evenly to the leaves of the Acer truncatum at a rate of 5 L per tree each time. Spray once each in mid-June, mid-July, and mid-August, for a total of 3 sprays.

4. A method for increasing the α-linolenic acid content in Acer truncatum seed oil, characterized in that: Apply potassium dihydrogen phosphate at a concentration of 4.5 g / L evenly to the leaves of the Acer truncatum at a rate of 5 L per tree each time. Spray once each in mid-June, mid-July, and mid-August, for a total of 3 sprays.

5. A method for increasing the γ-linolenic acid content in Acer truncatum seed oil, characterized in that: Apply potassium dihydrogen phosphate at a concentration of 7.5 g / L evenly to the leaves of the Acer truncatum at a rate of 5 L per tree each time. Spray once each in mid-June, mid-July, and mid-August, for a total of 3 sprays.

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