Houttuynia cordata color conversion agent and preparation method and application thereof

Abstract

The invention belongs to the technical field of agricultural product coloring, and particularly relates to a herba houttuyniae coloring agent as well as a preparation method and application thereof. The invention provides application of jasmonic acid methyl ester in color changing of houttuynia cordata. The action concentration of the jasmonic acid methyl ester is larger than or equal to 1 mmol / L. According to the method, methyl jasmonate is used as a color-changing agent of herba houttuyniae, so that accumulation of anthocyanin in a plant body can be promoted under the condition that normal growth of the plant is guaranteed, plant leaves are gradually changed from green to red, and the appearance quality of the herba houttuyniae is improved; the appearance color of the houttuynia cordata is improved, and meanwhile, the yield of roots, stems and leaves of the houttuynia cordata is not adversely affected.

Description

Technical Field

[0001] The invention belongs to the technical field of color change of agricultural products, and particularly relates to a houttuynia cordata color change agent and a preparation method and application thereof. Background Art

[0002] Houttuynia cordata Thunb., also known as Houttuynia cordata, fish scale grass, and stinky grass, is a plant of the genus Houttuynia in the family Saururaceae. Houttuynia cordata can not only be used as a dish and condiment, but also contains protein, soluble sugar, dietary fiber, carotene, vitamin C and various minerals, which have certain nutritional value for the human body; it also has very important medicinal value, has the effect of clearing away heat and detoxifying, and is especially suitable for respiratory diseases, and can enhance human immunity. The Houttuynia cordata sold on the market mainly includes red Houttuynia cordata and green Houttuynia cordata. Houttuynia cordata with red stems and leaves is favored by consumers because it is rich in vitamins, minerals, antioxidants and other nutrients.

[0003] Under sufficient light in the early stage of growth and development, the seedlings of Houttuynia cordata appear red all over, but the leaves will gradually turn green as the plant matures, affecting the appearance quality of Houttuynia cordata. There is currently no research related to the color change of Houttuynia cordata, and the color change of Houttuynia cordata is difficult. Therefore, it is particularly important to develop a color change product for green Houttuynia cordata in this field. Summary of the invention

[0004] The invention aims to provide a houttuynia cordata color changing agent and a preparation method and application thereof, so as to fill the gap of houttuynia cordata color changing, effectively promote the redding of green leaves, and have no adverse effect on other properties of houttuynia cordata.

[0005] The invention provides application of methyl jasmonate in color change of houttuynia cordata, wherein the action concentration of the methyl jasmonate is greater than or equal to 1 mmol / L.

[0006] Preferably, the effective concentration of the methyl jasmonate is 1 to 5 mmol / L.

[0007] Preferably, the effective concentration of the methyl jasmonate is 2 mmol / L.

[0008] Preferably, the application includes: increasing the anthocyanin content of Houttuynia cordata and deepening the color of Houttuynia cordata leaves.

[0009] The present invention also provides a houttuynia cordata color changing agent, wherein the active ingredient of the houttuynia cordata color changing agent comprises methyl jasmonate; and the concentration of methyl jasmonate in the houttuynia cordata color changing agent is ≥1mmol / L.

[0010] Preferably, the solvent of the Houttuynia cordata color changing agent is Tris-HCl buffer and anhydrous ethanol.

[0011] Preferably, the volume ratio of the Tris-HCl buffer to anhydrous ethanol is (0.25-1): (49-49.75);

[0012] The pH value of the Tris-HCl buffer is 7-8.5.

[0013] The present invention also provides a method for preparing the Houttuynia cordata color changing agent described in the above technical solution, comprising the following steps:

[0014] The Tris-HCl buffer, anhydrous ethanol and methyl jasmonate are mixed to obtain the Houttuynia cordata color changing agent.

[0015] The present invention also provides a method for changing the color of Houttuynia cordata, comprising the following steps: spraying the Houttuynia cordata color changing agent described in the above technical solution on Houttuynia cordata.

[0016] Preferably, the Houttuynia cordata color changing agent is sprayed when Houttuynia cordata has 5 to 6 true leaves; the spraying time is 9 to 13 days.

[0017] Beneficial effects:

[0018] The present invention provides an application of methyl jasmonate in the color change of Houttuynia cordata, wherein the effective concentration of the methyl jasmonate is ≥1mmol / L. The present invention uses methyl jasmonate to prepare a color change agent for Houttuynia cordata, and promotes the accumulation of anthocyanins in mature green Houttuynia cordata plants while ensuring the normal growth of the plants, so that the leaves of the plants gradually change from green to red, thereby improving the appearance quality of Houttuynia cordata; and while improving the appearance color of Houttuynia cordata, it does not have an adverse effect on the yield of the roots, stems and leaves of Houttuynia cordata.

[0019] The raw materials of the houttuynia cordata color-changing agent provided by the present invention are easy to obtain, the preparation method is safe and harmless, the production cost is low, and no adverse effects are produced on the environment of the planting area. It only needs to be simply sprayed on the surface of the leaves without complicated operations and high-cost application methods, and can effectively promote the redding of green leaves, has no adverse effects on other properties of houttuynia cordata, reduces production costs, saves labor input, and has strong development prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required to be used in the embodiments are briefly introduced below.

[0021] Figure 1 The phenotypes of Houttuynia cordata leaf color changes under different treatments;

[0022] Figure 2 The anthocyanin content of Houttuynia cordata leaves under different treatments; ns means no significant difference; *** means p < 0.001. DETAILED DESCRIPTION

[0023] The invention provides application of methyl jasmonate in color change of houttuynia cordata, wherein the action concentration of the methyl jasmonate is greater than or equal to 1 mmol / L.

[0024] In the present invention, as an embodiment, the effect concentration of the methyl jasmonate is ≥1mmol / L; as another embodiment, the effect concentration of the methyl jasmonate is 1-5mmol / L; as another embodiment, the effect concentration of the methyl jasmonate is 2mmol / L. As an embodiment, the CAS number of the methyl jasmonate is 39924-52-2. The present invention uses methyl jasmonate as an active ingredient, which can increase the anthocyanin content of Houttuynia cordata, deepen the color of Houttuynia cordata leaves, promote the reddening of green leaves, and has no adverse effects on other properties of Houttuynia cordata. In the present invention, as an embodiment, the Houttuynia cordata includes green leaf Houttuynia cordata.

[0025] The present invention also provides a houttuynia cordata color changing agent, wherein the active ingredient of the houttuynia cordata color changing agent comprises methyl jasmonate; and the concentration of methyl jasmonate in the houttuynia cordata color changing agent is ≥1mmol / L.

[0026] In the present invention, as one embodiment, the concentration of methyl jasmonate in the Houttuynia cordata color changing agent is ≥1mmol / L; as another embodiment, the concentration of methyl jasmonate in the Houttuynia cordata color changing agent is 1-5mmol / L; as another embodiment, the effective concentration of methyl jasmonate in the Houttuynia cordata color changing agent is 2mmol / L.

[0027] In the present invention, as an embodiment, the pH value of the Houttuynia cordata color changing agent is ≥7.0. As an embodiment, the solvent of the Houttuynia cordata color changing agent is Tris-HCl buffer and anhydrous ethanol. As an embodiment, the volume ratio of the Tris-HCl buffer and anhydrous ethanol is (0.25-1):(49-49.75); as another embodiment, the volume ratio of the Tris-HCl buffer and anhydrous ethanol is (0.35-0.50):(49.5-49.65). As an embodiment, the pH value of the Tris-HCl buffer is 7-8.5; as another embodiment, the pH value of the Tris-HCl buffer is 7.5-8.

[0028] The present invention also provides a method for preparing the houttuynia cordata color changing agent described in the above technical solution, comprising the following steps: mixing Tris-HCl buffer, anhydrous ethanol and methyl jasmonate to obtain the houttuynia cordata color changing agent.

[0029] In the present invention, as an embodiment, anhydrous ethanol and methyl jasmonate are mixed to obtain a stock solution, which is then mixed with the Tris-HCl buffer.

[0030] The raw materials of the houttuynia cordata color-changing agent provided by the invention are easy to obtain, the preparation method is safe and harmless, the production cost is low, and no adverse effects are produced on the environment of the planting area.

[0031] The present invention also provides a method for changing the color of Houttuynia cordata, comprising the following steps: spraying the Houttuynia cordata color changing agent described in the above technical solution on Houttuynia cordata.

[0032] In the present invention, as an embodiment, the Houttuynia cordata color changing agent is sprayed when Houttuynia cordata has 5 to 6 true leaves. As an embodiment, the spraying time is 9 to 13 days; as another embodiment, the spraying time is 10 days. As an embodiment, the Houttuynia cordata color changing agent is sprayed once a day. As an embodiment, the spraying includes foliar spraying. The present invention has no strict requirements on the spraying amount. The surface of the Houttuynia cordata leaf is sprayed evenly to spray the front and back of the leaf to make it wet until the leaf drips. As an embodiment, the spraying amount for each spraying is 25 mL.

[0033] The present invention only needs to spray the Houttuynia cordata color changing agent on the leaf surface without complicated operation and high-cost application method, so as to promote the accumulation of anthocyanins and the redding of green leaves, and has no adverse effect on other properties of Houttuynia cordata, thereby reducing production costs and saving labor input.

[0034] In order to further illustrate the present invention, a Houttuynia cordata color changing agent provided by the present invention and its preparation method and application are described in detail below in conjunction with the accompanying drawings and examples, but they should not be construed as limiting the scope of protection of the present invention.

[0035] Example 1

[0036] A method for preparing a houttuynia cordata color changing agent comprises the following steps:

[0037] (1) Weigh 12.1 g of Tris into a beaker, add about 800 mL of deionized water, stir and dissolve thoroughly, adjust the pH of the solution to 8.0 with concentrated hydrochloric acid, and then make the solution dilute to 1 L to prepare Tris-HCl buffer. Sterilize at high temperature and store at room temperature.

[0038] (2) Take 46 μL of 95 wt.% methyl jasmonate stock solution into a 2 mL centrifuge tube, add anhydrous ethanol to make the volume to 2 mL, to prepare a 100 mM methyl jasmonate stock solution, and store it in a -20°C refrigerator.

[0039] (3) taking 0.25 mL of the 100 mM methyl jasmonate stock solution from step (2) into a 50 mL centrifuge tube, and diluting the volume to 50 mL with the Tris-HCl buffer having a pH of 8 from step (1) to obtain a 500 μM methyl jasmonate mixed solution, which is the Houttuynia cordata color change agent.

[0040] Example 2

[0041] A method for preparing a Houttuynia cordata color change agent is similar to that of Example 1, the only difference being that, step (3): 0.35 mL of the 100 mM methyl jasmonate stock solution of step (2) is added to a 50 mL centrifuge tube, and the volume is fixed to 50 mL with Tris-HCl buffer of pH 8 of step (1), to obtain a 700 μM methyl jasmonate mixed solution, which is the Houttuynia cordata color change agent.

[0042] Example 3

[0043] A method for preparing a Houttuynia cordata color change agent is similar to that of Example 1, the only difference being that, step (3): 0.50 mL of the 100 mM methyl jasmonate stock solution of step (2) is added to a 50 mL centrifuge tube, and the volume is fixed to 50 mL with Tris-HCl buffer of pH 8 of step (1), to obtain a 1000 μM methyl jasmonate mixed solution, which is the Houttuynia cordata color change agent.

[0044] Example 4

[0045] A method for preparing a Houttuynia cordata color change agent is similar to that of Example 1, the only difference being that, step (3): 1.00 mL of the 100 mM methyl jasmonate stock solution of step (2) is added to a 50 mL centrifuge tube, and the volume is fixed to 50 mL with Tris-HCl buffer of pH 8 of step (1), to obtain a 2000 μM methyl jasmonate mixed solution, which is the Houttuynia cordata color change agent.

[0046] Comparative Example 1

[0047] A color-changing agent for Houttuynia cordata is a Tris-HCl buffer: 12.1 g of Tris is weighed and placed in a beaker, about 800 mL of deionized water is added, the mixture is fully dissolved and stirred, the pH of the solution is adjusted to 8.0 with concentrated hydrochloric acid, and then the solution is fixed to 1 L, sterilized at high temperature, and stored at room temperature for later use.

[0048] Test Example 1

[0049] The test site was the greenhouse of the College of Agriculture and Biology, Shanghai Jiao Tong University (31°028′N, 121°427′E). The Houttuynia cordata used was collected from the Houttuynia cordata planting demonstration base in Lianghe Town, Dangyang City, Yichang City, Hubei Province, and stored in the experimental site of the College of Agriculture and Biology, Shanghai Jiao Tong University. The material name is recorded as "DY10". Plug tray seedlings were raised in the greenhouse. When the seedlings grew to 3 true leaves, they were transplanted into pots for peat soil cultivation, with one plant per pot. Seedlings with basically the same plant height and leaf size were selected and randomly divided into 6 treatment groups, with 6 plants in each treatment group, and the following treatments were carried out:

[0050] Treatment Group 1 (Control): When the seedlings grow to 5-6 true leaves, spray them with clean water to moisten the leaf surface, and spray the branches and leaves as evenly as possible until the leaves drip water. Spray once a day, about 25 mL each time.

[0051] Treatment group 2 (Tris-HCl buffer group): When the seedlings grew to 5-6 true leaves, the Houttuynia cordata color change agent of comparative example 1 was sprayed to moisten the leaf surface, and the branches and leaves were sprayed as evenly as possible until the leaves dripped water. The spraying was performed once a day, and about 25 mL was sprayed each time;

[0052] Treatment group 3 (500 μM): When the seedlings grew to 5 to 6 true leaves, the Houttuynia cordata color change agent of Example 1 was sprayed to moisten the leaf surface, and the branches and leaves were sprayed as evenly as possible until the leaves dripped with water. The spraying was performed once a day, and about 25 mL was sprayed each time;

[0053] Treatment Group 4 (700 μM): When the seedlings grew to 5-6 true leaves, the Houttuynia cordata color change agent of Example 2 was sprayed to moisten the leaf surface, and the branches and leaves were sprayed as evenly as possible until the leaves dripped with water. The spraying was performed once a day, and about 25 mL was sprayed each time;

[0054] Treatment Group 5 (1000 μM): When the seedlings grew to 5-6 true leaves, the Houttuynia cordata color change agent of Example 3 was sprayed to moisten the leaf surface, and the branches and leaves were sprayed as evenly as possible until the leaves dripped with water. The spraying was performed once a day, and about 25 mL was sprayed each time;

[0055] Treatment Group 6 (2000 μM): When the seedlings grew to 5-6 true leaves, the Houttuynia cordata color change agent of Example 4 was sprayed to moisten the leaf surface, and the branches and leaves were sprayed as evenly as possible until the leaves dripped with water. Spray once a day, and spray about 25 mL each time.

[0056] Ten days after spraying each treatment group, leaves of Houttuynia cordata with the same size were collected to observe the color changes of the leaves under different treatment conditions. The anthocyanin content in the leaves of Houttuynia cordata was determined by an ELISA instrument according to the existing technology (Rabino I, Mancinelli AL. Light, temperature, and anthocyanin production [J]. Plant Physiology, 1986, 81 (3): 922-924. https: / / doi.org / 10.1104 / pp.81.3.922), and the significance analysis was performed. The results are shown in Tables 1 to 2 and Figures 1-2 shown.

[0057] Table 1 Anthocyanin content in leaves of Houttuynia cordata in different treatment groups

[0058]

[0059]

[0060] Table 2 Significance analysis of anthocyanin content in different treatment groups

[0061] \ SS df MS F P value Treatment 1.854 5 0.3709 F(5,42)＝80.89 P<0.001 Residual 0.1926 42 0.004585 / / Total 2.0472 47 / / /

[0062] According to Tables 1-2 and Figures 1-2 It can be seen that at 1000 μM and 2000 μM methyl jasmonate concentrations, the anthocyanin content in Houttuynia cordata leaves was significantly increased compared with the control group and other methyl jasmonate concentrations, and the color of Houttuynia cordata leaves was significantly deepened.

[0063] It can be seen from the above content that the technical solution provided by the present invention can enable the leaves of Houttuynia cordata to accumulate anthocyanins and deepen the color of the leaves of Houttuynia cordata.

[0064] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention, not all of the embodiments. People can also obtain other embodiments based on this embodiment without creativity, and these embodiments all fall within the protection scope of the present invention.

Claims

1. Application of methyl jasmonate in color change of Houttuynia cordata, wherein the effective concentration of the methyl jasmonate is ≥1mmol / L.

2. The use according to claim 1, characterized in that: The effective concentration of the methyl jasmonate is 1-5 mmol / L.

3. The use according to claim 1, characterized in that: The effective concentration of the methyl jasmonate is 2 mmol / L.

4. The use according to any one of claims 1 to 3, characterized in that: The application includes: increasing the anthocyanin content of Houttuynia cordata and deepening the color of Houttuynia cordata leaves.

5. A Houttuynia cordata color changing agent, characterized in that: The active ingredient of the houttuynia cordata color changing agent includes methyl jasmonate; the concentration of methyl jasmonate in the houttuynia cordata color changing agent is ≥1mmol / L.

6. The Houttuynia cordata color changing agent according to claim 5, characterized in that: The solvent of the Houttuynia cordata color changing agent is Tris-HCl buffer and anhydrous ethanol.

7. The Houttuynia cordata color changing agent according to claim 6, characterized in that: The volume ratio of the Tris-HCl buffer to anhydrous ethanol is (0.25-1): (49-49.75); The pH value of the Tris-HCl buffer is 7-8.

5.

8. The method for preparing the Houttuynia cordata color changing agent according to any one of claims 5 to 7, characterized in that: The steps include: The Tris-HCl buffer, anhydrous ethanol and methyl jasmonate are mixed to obtain the Houttuynia cordata color changing agent.

9. A method for changing the color of Houttuynia cordata, characterized in that: The method comprises the following steps: spraying the Houttuynia cordata color changing agent according to any one of claims 5 to 7 or the Houttuynia cordata color changing agent obtained by the preparation method according to claim 8 on Houttuynia cordata.

10. The method for changing the color of Houttuynia cordata according to claim 9, characterized in that: When Houttuynia cordata has 5 to 6 true leaves, the Houttuynia cordata color changing agent is sprayed; the spraying time is 9 to 13 days.

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