A method for increasing folic acid content in wheat seedlings

Abstract

The present invention relates to a method for increasing the folate content of wheat seedlings, belonging to the technical field of agricultural product processing. The method is characterized in that wheat with a high germination rate is used as raw material, the seeds are sterilized and soaked, salicylic acid and phenylalanine are embedded in polysaccharides to form a composite coating material, the seeds are coated with a film, and a coating is formed on the surface of the wheat grains after drying; and the wheat seedlings with high folate content are cultivated by soaking and absorbing water, and regulating temperature, humidity and light conditions. The coating material used in the present invention is not only inexpensive, readily available, and environmentally friendly, but also has a simple preparation method and can effectively promote folate accumulation in wheat seedlings, with the folate content of the wheat sprouts reaching 400 to 600 μg / 100g dry weight.

Description

1. Technical Field

[0001] The invention relates to a method for increasing the folic acid content of wheat seedlings, and belongs to the technical field of agricultural product processing. 2. Background Technology

[0002] With the rapid development and progress of my country's economy and science and technology, more and more consumers are beginning to pay attention to foods with health benefits. In recent years, developing wheat sprouts, rich in phenolic acids, chlorophyll, vitamin C, and dietary fiber, into functional foods with benefits such as weight loss and bowel cleansing has become a research hotspot. Wheat sprouts are low in crude fiber and have a good taste. Developing wheat sprouts into functional foods not only retains some of the nutrients in the grain but also enriches them with functional ingredients such as folic acid, phenolic acids, and dietary fiber, resulting in higher nutritional and functional qualities than grains and existing leaf products.

[0003] Currently, the enrichment of functional ingredients such as folic acid in food ingredients and the development of their products are attracting significant attention. As a one-carbon unit donor in organisms, folic acid is an essential precursor for the biosynthesis of nucleic acids, amino acids, and pantothenic acid, and plays a vital role in maintaining human physiological function and health. However, folic acid intake is generally insufficient in most countries and regions. While plants and microorganisms can synthesize folic acid de novo, animals cannot. Therefore, plant-based foods are the primary source of folic acid for humans. Consequently, increasing the folic acid content in plant-based food ingredients has attracted considerable attention.

[0004] Seed coating mainly wraps exogenous materials such as biopolymers, colorants, biocontrol agents and microbial coatings on the surface of seeds, which can protect crops from biotic and abiotic stresses, thereby extending the shelf life of seeds and improving seed performance. Among them, hydrogel is a material with high water absorption and water retention, so in arid and harsh environments, hydrogel-coated seeds can provide seeds with a moist and breathable microenvironment to promote seed germination and growth. In order to improve the performance of the coating, an appropriate amount of exogenous stimulating substances can be added. Such a coating can not only provide a moist environment but also slowly release and deliver exogenous substances. Compared with the method of directly spraying exogenous substances to increase folic acid content, the method of delivering exogenous substances through coating can efficiently deliver exogenous substances, thereby reducing resource waste.

[0005] Currently, the main ways to enrich functional factors in crops are gene regulation, light regulation, and stimulating crops by directly spraying growth hormones. Light regulation uses the light signals received by the photoreceptors in plants during their growth and development to induce the growth, development, and metabolism of the plants. The patent (publication number CN201911185556.1, publication date November 27, 2019) discloses "a germination method for improving the quality of germinated quinoa by light treatment". This method uses composite light with a light quality ratio of blue light to red light of 1:1 to 1:4 to cultivate germinated quinoa grains, with a light intensity of 5000 to 6000 lx and a germination time of 60 to 70 hours. This method effectively increases the content of gamma-aminobutyric acid in quinoa grains and enhances the antioxidant properties of quinoa. However, this method can only be completed on a small scale in the laboratory. Considering the actual production conditions and costs, large-scale production cannot be achieved. Another method is to directly spray growth hormones. The patent (publication number CN201410192042.X, publication date May 8, 2014) discloses a "method for increasing stevia yield, RA glycoside and total glycoside content using exogenous salicylic acid." This invention uses exogenous salicylic acid to spray the leaves of stevia, thereby achieving the purpose of increasing its yield and total glycoside content. The method is simple and easy to operate, but when spraying the hormone, it is impossible to accurately irrigate the seeds, and it will remain in the air. This not only leads to waste of materials, but also affects the growth of other crops in the planting area. Therefore, the development of a method that can efficiently and accurately deliver growth hormone to seeds to enrich folic acid is of great significance to the agricultural product processing industry.

[0006] The present invention selects wheat grains with a high germination rate as raw materials, and obtains wheat seedlings with a high folic acid content through disinfection and soaking, coating material preparation, grain coating and wrapping, and controlled germination conditions. The method has the advantages of simple coating material preparation, green and environmental protection, and effective promotion of folic acid accumulation in wheat seedlings. 3. Summary of the Invention

[0007] Technical issues

[0008] The present invention aims to provide a method for increasing the folic acid content of wheat seedlings. The method comprises the following steps: selecting wheat grains with a high germination rate as raw materials, embedding salicylic acid and phenylalanine with chitosan, konjac glucomannan or arabinoxylan to prepare a composite coating, wrapping the wheat grains with the coating, and controlling the germination conditions to cultivate wheat seedlings with a high folic acid content.

[0009] Technical Solution

[0010] The technical solution of the present invention is summarized as follows: wheat with a high germination rate is selected as raw material, and wheat seedlings with high folic acid content are obtained through disinfection and soaking, preparation of a composite coating material, grain coating and wrapping, and controlled germination conditions. The specific steps include:

[0011] (1) Disinfection and soaking: According to a known method, wheat grains that have been selected and cleaned are disinfected with a 1% to 3% (w / v) sodium hypochlorite solution for 15 to 20 minutes, rinsed with purified water to a pH of 6.8 to 7.2, and then soaked in purified water at 20 to 25°C for 6 hours. The soaked wheat grains are then rinsed twice with purified water;

[0012] (2) Preparation of composite coating material: 0.5% to 1.5% (w / v) chitosan, konjac glucomannan or arabinoxylan, and 0.6% to 0.9% (w / v) glycerol are sequentially added to pure water and fully stirred and dissolved at 60 to 70°C; 0.1% to 0.3% (w / v) salicylic acid and 0.1% to 0.3% (w / v) phenylalanine are then added, fully stirred, and ultrasonically degassed for 30 minutes; the viscosity of the composite coating material prepared is 900 to 1300 mPa·s, and it has high water absorption, high viscosity, and easy film-forming properties; preferably, 1.0% (w / v) chitosan, 0.6% (w / v) glycerol, 0.2% (w / v) salicylic acid, and 0.2% (w / v) phenylalanine are sequentially added to pure water to prepare the coating, at which point the viscosity of the composite coating material is 1000 mPa·s, and the coating has the best water retention and sustained-release effects;

[0013] (3) Seed coating: Mix the wheat seeds with the coating solution at a mass volume ratio of 1:10 to 1:20 (w / v). After 2 to 3 minutes, remove the seeds and dry them in an oven at 30 to 40°C for 18 to 24 hours to form a coating with a thickness of 4 to 6 mm.

[0014] (4) Wheat sprout cultivation: The coated wheat kernels are evenly spread on the germination tray. The temperature is set at 25-30°C, the humidity is 80%-90%, and the seeds are germinated in the dark for 1-2 days. Then, the seeds are cultivated under a light intensity of 1500-3000 lx for 3-4 days. Water is applied every 8 hours during the cultivation period to obtain wheat sprouts with a length of 8-10 cm. The preferred cultivation temperature is 28°C, the humidity is 85%, the seeds are germinated in the dark for 1 day, and the seeds are cultivated under a light intensity of 2000 lx for 4 days. The length of the cultivated wheat sprouts is 9 cm, and the folate content of the wheat sprouts is the highest at this time.

[0015] Beneficial effects

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] (1) The present invention uses seed coating to enrich folic acid in the wheat germination stage, which is simple to operate and highly practical;

[0018] (2) The seed coating used in the present invention is biodegradable and can protect the integrity of wheat grains, inhibit fungal damage, and promote the enrichment of folic acid functional factors in wheat grains;

[0019] (3) The wheat seedlings cultivated by the technology of the present invention have a high folic acid content, which can reach 400-600 μg / 100g. 4. Specific Implementation Methods

[0020] Example 1

[0021] According to a known method, wheat grains that have been selected and cleaned of impurities are sterilized with a 1% to 3% (w / v) sodium hypochlorite solution for 15 to 20 minutes, rinsed with purified water to a pH of 6.8 to 7.2, then soaked in purified water at 20 to 25°C for 6 hours, and rinsed twice with purified water. 1.0% (w / v) chitosan and 0.6% (w / v) glycerol are added to the purified water in sequence and thoroughly stirred to dissolve at 60 to 70°C. 0.2% (w / v) salicylic acid and 0.2% (w / v) phenylalanine are then added, stirred thoroughly, and ultrasonically degassed for 30 minutes. The wheat grains are then mixed uniformly with the coating solution at a mass-to-volume ratio of 1:15 (w / v). After 2 minutes, the seeds are removed and dried in a 37°C oven for 20 hours to form a coating with a thickness of 5 mm. The coated wheat grains were evenly spread on a germination tray, germinated at 28°C, 85% humidity in the dark for 1 day, and cultivated under a light intensity of 2000 lx for 4 days. Watering was carried out every 8 hours during the cultivation period to obtain wheat seedlings with a length of 9 cm. The folic acid content of the dry weight of the wheat sprouts reached 600 μg / 100 g.

[0022] Example 2

[0023] The wheat grain disinfection soaking process is the same as in Example 1. 0.5% (w / v) konjac glucomannan and 0.9% (w / v) glycerol are added to purified water in sequence and thoroughly stirred at 60-70°C to dissolve; 0.1% (w / v) salicylic acid and 0.3% (w / v) phenylalanine are then added, thoroughly stirred, and ultrasonically degassed for 30 minutes. The wheat grains are mixed evenly with the coating solution at a mass volume ratio of 1:20 (w / v), removed after 3 minutes, and placed in a 40°C oven to dry for 18 hours, forming a coating with a thickness of 4mm. The coated wheat grains are evenly spread on germination trays and germinated in the dark at 25°C and 80% humidity for 1 day. They are then incubated under a light intensity of 1500 lx for 3 days, watered once every 8 hours during the incubation period, to obtain wheat seedlings with a length of 8 cm. The folate content of the wheat sprouts reaches 550 μg / 100g dry weight.

[0024] Example 3

[0025] The wheat grain disinfection soaking process is the same as that in Example 1. 1.5% (w / v) arabinoxylan and 0.8% (w / v) glycerol are added to pure water in sequence, and the mixture is thoroughly stirred and dissolved at 60-70°C; 0.3% (w / v) salicylic acid and 0.1% (w / v) phenylalanine are then added, and ultrasonic degassing is performed for 30 minutes after thorough stirring. The wheat grains are mixed evenly with the coating solution in a mass volume ratio of 1:10 (w / v), taken out after 3 minutes, and placed in a 35°C oven to dry for 24 hours to form a coating with a thickness of 6 mm. The coated wheat grains are evenly spread on a germination tray, germinated at 30°C, 90% humidity, and protected from light for 2 days, and then cultivated for 4 days under a light intensity of 3000 lx. Watering is performed every 8 hours during the cultivation period to obtain wheat seedlings with a length of 10 cm. The folic acid content of the wheat sprouts reaches 400 μg / 100g.

[0026] The above detailed description of the embodiments of the present invention is provided for ease of understanding only and should not be construed as limiting the scope of the present invention. Similarly, any person skilled in the art may make various possible equivalent changes and substitutions based on the technical solutions and the description of the preferred embodiments of the present invention, and all such changes and substitutions shall fall within the scope of protection of the claims of the present invention.

Claims

1. A method for increasing the folic acid content of wheat seedlings, characterized in that The method uses wheat grains with a high germination rate as raw materials, sterilizes and soaks, prepares coating materials, coats the grains, and controls germination conditions to cultivate wheat seedlings with a high folic acid content, and specifically includes the following steps: (1) Disinfection and soaking: According to a known method, wheat grains that have been selected and cleaned are disinfected with 1% to 3% (w / v) sodium hypochlorite solution for 15 to 20 minutes, rinsed with purified water to a pH of 6.8 to 7.2, then soaked in purified water at 20 to 25°C for 6 hours, and then rinsed twice with purified water; (2) Preparation of composite coating material: 0.5% to 1.5% (w / v) polysaccharide and 0.6% to 0.9% (w / v) glycerol were sequentially added to purified water and thoroughly stirred at 60 to 70°C to dissolve; 0.1% to 0.3% (w / v) salicylic acid and 0.1% to 0.3% (w / v) phenylalanine were then added, thoroughly stirred, and ultrasonically degassed for 30 minutes. The viscosity of the composite coating material was 900 to 1300 mPa·s. (3) Seed coating: Mix the wheat seeds with the coating solution at a mass volume ratio of 1:10 to 1:20 (w / v). After 2 to 3 minutes, remove the seeds and dry them in an oven at 30 to 40°C for 18 to 24 hours to form a coating with a thickness of 4 to 6 mm. (4) Wheat sprout cultivation: The coated wheat grains were evenly spread on a germination tray, germinated in the dark at 25-30°C and 80%-90% humidity for 1-2 days, and then cultivated under a light intensity of 1500-3000 lx for 3-4 days. Water was applied every 8 hours during the cultivation period to obtain wheat seedlings with a length of 8-10 cm.

2. According to claim 1, a method for increasing folic acid in wheat sprouts based on seed coating technology, the technical feature of which is that the coating material is chitosan, konjac glucomannan or arabinoxylan, and the folic acid content of the wheat sprouts dry weight reaches 400-600 μg / 100g.