Application of nanocarbon sol in increasing organic selenium content and / or protein content of broccoli by coupling free selenium

Abstract

The invention relates to an application of nano carbon sol in increasing the content of organic selenium and / or protein in broccoli by coupling free selenium, and the content of the organic selenium and the protein in the broccoli can be obviously increased by spraying the nano carbon sol to the broccoli, preferably, a complexing agent containing the nano carbon sol and selenite. And the increase degree of the organic selenium content is related to the variety of the broccoli, particularly, the method has outstanding selenium enrichment capacity for broccoli B3 approximate resources, has extremely wide industrial development and marketization prospects, and provides a natural biological factory and a technical process for industrial development of the broccoli. The invention further relates to a method for increasing the content of organic selenium and / or protein in broccoli, and the capacity of synthesizing the organic selenium and the protein of the broccoli is remarkably improved by spraying the nano carbon sol for three times.

Description

Technical Field

[0001] The invention relates to the technical field of agriculture, and in particular to application of nano carbon sol in coupling free selenium to increase the organic selenium content and / or protein content of broccoli. Background Art

[0002] Broccoli (Brassica oleracea L. var. italica Plenck) is an annual or biennial herbaceous plant of the Brassica family, a common vegetable, known as the "crown of vegetables" because it is rich in nutrients such as vitamin C, protein and minerals. Research in the past 30 years has found that broccoli is also rich in a beneficial glucosinolate 4-methylsulfinylbutyl glucosinolate (glucoraphanin, RAA or GRA). When broccoli is mechanically damaged, bitten by insects, or chewed and eaten, RAA in the vacuole can react with myrosinase (MY), a β-thioglucosinolate hydrolase in the cytoplasm, to generate sulforaphane (also known as sulforaphane, SFN) with anti-cancer activity under appropriate pH conditions. Studies have found that sulforaphane in broccoli is one of the most powerful anti-cancer ingredients found in vegetable crops. It can significantly prevent and reduce the risk of lung cancer, liver cancer, gastric cancer, breast cancer, colon cancer, bladder cancer, prostate cancer and other cancers. It has a good curative and alleviating effect on patients with cardiovascular and cerebrovascular diseases, myopia and "three highs", and has become an international frontier and hot spot.

[0003] Studies have found that selenium cannot be synthesized in the human body. The total selenium content of the human body is 6-20mg. Selenium is distributed throughout various tissues, organs and body fluids, with the highest concentration in the kidneys. It is very important for improving immunity and preventing cancer. Selenium in men is mostly concentrated in the testicles, prostate and vas deferens, and will be discharged from the body along with semen. When selenium is deficient, it is easy to cause a decline in human immunity. More than 40 diseases that threaten human health and life are related to selenium deficiency in the human body, such as cancer, cardiovascular disease, liver disease, cataracts, pancreatic swelling disease, diabetes, reproductive system diseases, premature aging of the human body, etc. Normally, the total daily requirement per person is that Chinese adults supplement selenium with food for more than 25μg per day to have a health-care effect, and selenium-deficient adults supplement selenium with food for more than 50μg per day to reach the minimum selenium supplementation level recommended by the World Health Organization. Inorganic selenium is often toxic to the human body, and the organic state is the best way for the human body to obtain selenium. Finding and building green, ecological and efficient organic selenium conversion carriers and technologies have become a highland of scientific and technological competition and core key technologies in the field of big health at home and abroad. It is reported that selenium in broccoli exists in the form of organic selenium, and there is no free inorganic selenium. Therefore, broccoli is a green, ecological, and scientific biological carrier for obtaining organic selenium, and the identification, screening, and optimization of high conversion efficiency resources and coupled conversion technology have become an efficient new quality productivity, an important source and technology to meet the current market demand for selenium products (selenium tablets, cardiovascular and cerebrovascular prevention, anti-cancer products, etc.). CN105103876A discloses a cultivation method for selenium-rich broccoli, comprising the following steps: (1) land preparation and fertilization, (2) seed treatment, (3) sowing, (4) water and fertilizer management, and (5) timely harvesting. By spraying selenium-rich foliar fertilizer on broccoli during the rosette stage, nutrients are provided for the growth of broccoli, thereby cultivating selenium-rich broccoli with rich nutritional value; at the same time, the combined use of base fertilizer and seed soaking solution not only increases the yield of broccoli, but also can protect the soil.

[0004] Broccoli is rich in protein, with a protein content of about 3.6 g / 100 g fresh weight (FW). The protein in broccoli contains all essential amino acids and is a complete protein. This means that it provides all the essential amino acids that the human body cannot synthesize on its own and must obtain through the diet, and plays an important role in maintaining human health and physiological functions. Compared with other vegetables, broccoli has a relatively high protein content. The protein content in spinach is about 2.9 g / 100 g fresh weight, the protein content in tomatoes is about 0.9 g / 100 g fresh weight, and the protein content in cucumbers is about 0.7 g / 100 g fresh weight. It can be seen that the protein content of broccoli is higher than these common vegetables, and is almost equivalent to or higher than milk protein, which contains about 3.2 g / 100 g liquid weight.

[0005] Nevertheless, as a plant-based food, broccoli provides a cholesterol-free protein source and contains other rich nutrients, such as vitamin C, vitamin K, dietary fiber, minerals (such as calcium and iron), and the anti-cancer active ingredient sulforaphane (SFN), also known as sulforaphane, which are indispensable components of maintaining a healthy diet. Therefore, broccoli is an important part of a balanced diet, especially for vegetarians and people who need to increase their plant protein intake.

[0006] In summary, how to increase the organic selenium content and / or protein content of broccoli has become one of the problems that need to be solved urgently in this field. Summary of the invention

[0007] In order to solve the above technical problems, the present invention provides an application of nanocarbon sol in coupling free selenium to increase the organic selenium content and / or protein content of broccoli. By spraying nanocarbon sol on broccoli and optimizing and analyzing the times and concentrations of sodium selenite spraying, the organic selenium and protein content of broccoli is increased, and the degree of organic selenium increase is related to the variety of broccoli. The invention has extremely broad prospects for industrial development and marketization, and provides a natural biological factory and technical process for the industrial development of broccoli.

[0008] To achieve this object, the present invention adopts the following technical solutions:

[0009] In a first aspect, the present invention provides the use of nanocarbon sol in coupling free selenium to increase the organic selenium and / or protein content of broccoli.

[0010] The present invention uses nano carbon sol to enrich and couple free selenium, and the organic selenium synthesis process is as follows: Figure 1As shown, first, selenium in plants is regulated by SelD to produce SeP in the first stage of the reaction. The SelD gene encodes the first step of all known selenium processes in the cell, and then the redox reaction is regulated by SeIA and SeIU to produce different selenoproteins. Nanocarbon acts as a catalyst in this kinetic synthesis reaction, which can quickly aggregate the substrate selenium with the protein, increase the contact and reaction surface, and thus increase the biochemical reaction rate. The study found that SelA and SelU are the first five Seld overlapping genes, as well as yedF and duf3343. The latter two genes are believed to play an undetermined role in the reduction and / or transport of selenium. It is reported that the overlapping genes found in this study are from the glycosyltransferase of the TIGR04348 family, which has also attracted the attention of researchers. Although this gene accounts for less than 5% of all SelD overlapping genes, TIGR04348 has never been involved in selenium metabolism, and no members of its protein family have been characterized. In addition, in-depth study of the genetic background of SelD-tigr04348 revealed a third common co-localized gene: a homolog of egtB, which encodes an enzyme that forms the CS bond in the biosynthesis of ergothioneine. This is a ubiquitous metabolite found in microorganisms and mammals, with multiple functions including antioxidant and cytoprotective factor. More than 800 examples of this three-gene biosynthesis have been found in different bacterial genomes, suggesting that it may encode a biosynthetic pathway that widely utilizes selenium. The latest study found that by characterizing the above biosynthetic pathway through metabolomics and biochemical methods, it was found that the actinomycetes Amycolatopsis palatopharyngis and the greedy phage Variovorax paradoxus containing the SelD-egtB-tigr04348 gene cluster can produce ergothioneine and its selenoketone analogs. Because selenoketones are more reductive than ergothioneine, they are considered to be more effective antioxidants. Further analysis revealed that selenoketones are actually the products of the new gene cluster. The team named it "Sen". It was therefore determined that SenA, SenB, and SenC encode an egtB homolog, a putative glycosyltransferase, and a SelD homolog, respectively.

[0011] At the same time, selenium mainly exists in broccoli in the form of selenocysteine ​​(SeC), methylselenocysteine ​​(MSeC) and selenomethionine (SeM). Selenium can accelerate the synthesis and metabolism of cysteine ​​through the plant immune system, thereby promoting the amino acid synthesis of broccoli. Specifically, it can significantly improve the metabolic synthesis pathways of aliphatic glucosinolates with methionine as precursors and selenoproteins with cysteine ​​as precursors. The main genes involved include CYP79F1, CYP83A1, SelD genes in the CYP450 family, and the synthesis of ATP, etc., which indirectly increases the protein content of broccoli and the accumulation of beneficial glucosinolates and selenoproteins. This has become a research frontier at home and abroad, but the deep regulatory mechanism is still unclear. The preliminary conclusion of the enzymatic function of nanocarbon is that it accelerates charge aggregation, which accelerates secondary metabolic reactions and plays the role of an efficient loader. The specific molecular mechanism still needs to be studied.

[0012] Preferably, the solid content of nanoscale carbon in the nano-carbon sol is 0.2-0.8wt% (for example, it can be 0.2wt%, 0.3wt%, 0.4wt%, 0.5wt%, 0.6wt%, 0.7wt% or 0.8wt%, etc.), preferably 0.4-0.6wt% (for example, it can be 0.4wt%, 0.45wt%, 0.5wt%, 0.55wt% or 0.6wt%, etc.).

[0013] Preferably, the particle size of nanoscale carbon in the nanocarbon sol is 0.1 to 200 nm (for example, it can be 0.1 nm, 0.5 nm, 1 nm, 10 nm, 20 nm, 50 nm, 100 nm, 150 nm or 200 nm, etc.), preferably 1 to 6 nm (for example, it can be 1 nm, 2 nm, 3 nm, 4 nm, 5 nm or 6 nm, etc.).

[0014] Preferably, the pH of the nanocarbon sol is 2-4 (eg, 2, 2.5, 3, 3.5 or 4, etc.).

[0015] Preferably, the content of nanoscale carbon in the nanocarbon sol is greater than 95.5% (for example, it may be 95.5%, 96%, 96.5%, 97%, 97.5%, 98%, 98.5%, 99%, 99.5% or 100%, etc.).

[0016] Preferably, the method of increasing the organic selenium content of broccoli comprises increasing the organic selenium content of any one of the broccoli curd, leaves, main stem, stalk, flower bud or seeds, or a combination of at least two of the broccoli curd, leaves, main stem, flower stalk, flower bud or seeds.

[0017] Preferably, the broccoli includes the hybrid Zhongqing 15 and / or the female parent of the hybrid Zhongqing 15.

[0018] Preferably, the organic selenium includes any one of selenocysteine, methylselenocysteine ​​or selenomethionine, or a combination of at least two of them.

[0019] In a second aspect, the present invention provides a composite agent for increasing the organic selenium content and / or protein content of broccoli, wherein the composite agent contains nanocarbon sol.

[0020] Preferably, the method of increasing the organic selenium content of broccoli comprises increasing the organic selenium content of any one of the broccoli curd, leaves, main stem, stalk, flower bud or seeds, or a combination of at least two of the broccoli curd, leaves, main stem, flower stalk, flower bud or seeds.

[0021] Preferably, the broccoli includes the hybrid Zhongqing 15 and / or the female parent of the hybrid Zhongqing 15.

[0022] Preferably, the solid content of nanoscale carbon in the nano-carbon sol is 0.2-0.8wt% (for example, it can be 00.2wt%, 0.3wt%, 0.4wt%, 0.5wt%, 0.6wt%, 0.7wt% or 0.8wt%, etc.), preferably 0.4-0.6wt% (for example, it can be 0.4wt%, 0.45wt%, 0.5wt%, 0.55wt% or 0.6wt%, etc.).

[0023] Preferably, the particle size of nanoscale carbon in the nanocarbon sol is 0.1 to 200 nm (for example, it can be 0.1 nm, 0.5 nm, 1 nm, 10 nm, 20 nm, 50 nm, 100 nm, 150 nm or 200 nm, etc.), preferably 1 to 6 nm (for example, it can be 1 nm, 2 nm, 3 nm, 4 nm, 5 nm or 6 nm, etc.).

[0024] Preferably, the pH of the nanocarbon sol is 2-4 (eg, 2, 2.5, 3, 3.5 or 4, etc.).

[0025] Preferably, the content of nanoscale carbon in the nanocarbon sol is greater than 95.5% (for example, it may be 95.5%, 96%, 96.5%, 97%, 97.5%, 98%, 98.5%, 99%, 99.5% or 100%, etc.).

[0026] Preferably, the composite agent further contains a selenite solution.

[0027] The present invention combines nanocarbon sol with selenite, and the two synergistically improve the organic selenium and protein content of broccoli. Selenite is a donor of selenium, and nanocarbon sol can enrich the selenium provided by selenite, thereby improving the efficiency of broccoli in converting inorganic selenium into organic selenium, and then improving the content of organic selenium in broccoli. After Rotruck et al. discovered and confirmed in 1973 that selenium is a component of animal and human glutathione peroxidase, the importance of selenium in agricultural production, human and animal health and environmental protection has attracted much attention. Studies have found that nanocarbon sol in the nitrite state can quickly polymerize to form a suspension or sol state, and selenium, zinc, etc. in the nitrite state also produce a large number of free radicals in the process of higher plant metabolism and environmental stress. These free radicals can be removed by corresponding enzyme systems such as superoxide dismutase (SOD) and catalase (Cat), and can also be removed by glutathione peroxidase system (GSH-Px). It can be seen that nitrite, especially selenium, can upregulate the antioxidant enzyme system in plants, but there are certain dosage requirements. Too high a dosage will cause adversity and physiological disorders.

[0028] Studies have shown that GSH-Px has been detected in different tissues of different plant species, and that selenium application can enhance the activity of GSH-Px in plant tissues, thus confirming that selenium (inorganic selenium, nitrite, and organic forms) also has an antioxidant effect in plants. 4+ The solution was used to treat wheat and three kinds of forage grasses. After 10 days, it was found that 60% to 80% of the selenium was related to protein function, and 20% to 30% of the selenium was related to various selenium-containing amino acids. The study of soybean components in areas with different inorganic selenium levels showed that 42.6% to 62.6% of the selenium in soybeans was bound to water-soluble proteins, and soybean protein was the main component enriched with selenium. This shows that inorganic selenium is involved in the anabolism of protein in plants.

[0029] Preferably, the selenite includes any one of sodium selenite, potassium selenite, sodium hydrogen selenite or potassium hydrogen selenite, or a combination of at least two thereof.

[0030] Preferably, the concentration of the selenite solution is 0-300 mg / L (for example, 0 mg / L, 10 mg / L, 20 mg / L, 50 mg / L, 100 mg / L, 150 mg / L, 200 mg / L, 250 mg / L or 300 mg / L, etc.), preferably 180-220 mg / L (preferably 180 mg / L, 190 mg / L, 200 mg / L, 210 mg / L or 220 mg / L, etc.).

[0031] Preferably, the volume ratio of the nanocarbon sol to the selenite solution in the composite is 1:(0-3), preferably 1:(0.3-0.5).

[0032] The specific point values ​​of the above (0-3) can be selected as 0, 0.005, 0.01, 0.02, 0.05, 0.1, 0.2, 0.5, 1, 1.5, 2, 2.5 or 3, etc.

[0033] The specific point values ​​of the above (0.3-0.5) can be selected from 0.3, 0.35, 0.4, 0.45 or 0.5, etc.

[0034] Preferably, the organic selenium includes any one of selenocysteine, methylselenocysteine ​​or selenomethionine, or a combination of at least two of them.

[0035] In a third aspect, the present invention provides a method for increasing the organic selenium content and / or protein content of broccoli, the method comprising: spraying the composite agent described in the second aspect onto the broccoli.

[0036] Preferably, the method specifically comprises: spraying the compound once during the 25-30 days (for example, 25 days, 26 days, 27 days, 28 days, 29 days or 30 days, etc.) vegetative development period, 35-40 days (for example, 35 days, 36 days, 37 days, 38 days, 39 days or 40 days, etc.) important vegetative development period and 55-60 days (for example, 55 days, 56 days, 57 days, 58 days, 59 days or 60 days, etc.) flower bud differentiation period after planting the broccoli in the adult stage.

[0037] Preferably, the spraying amount (coupling level) of the composite agent is 1-20 L / ha (for example, it can be 1 L / ha, 2 L / ha, 5 L / ha, 10 L / ha, 15 L / ha or 20 L / ha, etc.), preferably 18-20 L / ha (for example, it can be 18 L / ha, 18.5 L / ha, 19 L / ha, 19.5 L / ha or 20 L / ha, etc.).

[0038] Other specific point values ​​within the above numerical ranges can be selected and will not be described in detail here.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] The present invention provides a nano carbon sol, and further preferably a composite agent containing nano carbon sol and selenite. By spraying the composite agent on broccoli, the crop's own protein coupling can significantly increase the content of organic selenium, and the degree of increase is closely related to the variety and genotype of the broccoli. The nano carbon sol can be widely used on cruciferous crops, significantly increasing the content of organic selenium (selenomethionine, selenocysteine, etc.) and protein content, especially for broccoli B3 similar resources, which has outstanding selenium enrichment ability, which is dozens or even hundreds of times higher than ordinary varieties. The organic selenium content in the B3 broccoli head can reach 3010.3μg / kg FW, which has extremely broad industrial development and market prospects, and provides a natural biological factory and technical process for the industrial development of broccoli. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 This is a diagram of the synthesis process of organic selenium;

[0042] Figure 2 This is the HPLC chromatographic result of organic selenium components in broccoli florets. DETAILED DESCRIPTION

[0043] To further illustrate the technical means and effects of the present invention, the present invention is further described below in conjunction with the embodiments and the accompanying drawings (tables). It is understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention.

[0044] If no specific techniques or conditions are specified in the examples, the techniques or conditions described in the literature in the field or the product instructions are used. If no manufacturer is specified for the reagents or instruments used, they are all conventional products that can be purchased through regular channels.

[0045] Materials, reagents and instruments used in the following examples:

[0046] Broccoli: The homozygous inbred line B1 and the hybrid Ogura-CMS F1 "Zhongqing 15" (B3) were both bred by the cabbage and broccoli project of the Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences. B1 was derived from the hybrid F1 generation "BY8" of the imported material from Japan and bred by self-pollination for 6 generations (F7), and "Zhongqing 15" was obtained by hybridizing the sterile line CMS1951 bred by the Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences with B1.

[0047] Nanocarbon sol: provided by Zhongtu Liangtian Ecological Environmental Protection (Shandong) Co., Ltd. (General Manager Liu Junyi);

[0048] Sodium selenite and other analytically pure substances were purchased from Beijing Xinshengke Technology Co., Ltd. (Amresco, analytically pure substances);

[0049] The main instruments used include electronic balance, atomic fluorescence spectrometer, Dumas nitrogen analyzer, high performance liquid chromatography HPLC (Shimadzu) (Vegetable Quality Monitoring Center of the Ministry of Agriculture and Rural Affairs), etc.

[0050] Preparation Example 1-10

[0051] This preparation example prepared a composite agent for increasing the organic selenium content of broccoli, and the raw materials and proportions are shown in Table 1. The preparation method of Preparation Example 1 includes: mixing a nanocarbon sol with a nano-scale carbon solid content of 0.5wt% and a sodium selenite solution with a concentration of 200mg / L, and the volume ratio of the nanocarbon sol to the sodium selenite solution is 1:0.4. Preparation Examples 2-10 are carried out with reference to the preparation method of Preparation Example 1.

[0052] Table 1

[0053]

[0054]

[0055] Preparation Example 11

[0056] This preparation example prepares a composite agent for increasing the organic selenium content of broccoli, which is different from Preparation Example 1 only in that the sodium selenite solution is replaced by a potassium selenite solution.

[0057] Preparation Example 12

[0058] This preparation example prepares a composite agent for increasing the organic selenium content of broccoli, which is different from Preparation Example 1 only in that the sodium selenite solution is replaced by a sodium hydrogen selenite solution.

[0059] Comparative Preparation Example 1

[0060] This preparation example prepares a composite agent for increasing the organic selenium content of broccoli, which is different from Preparation Example 1 only in that it does not contain nanocarbon sol.

[0061] Example 1

[0062] The present embodiment provides a method for increasing the organic selenium content of broccoli, comprising the following steps: spraying the composite agent provided in Preparation Example 1 once during the 25-30 day vegetative development period, the 35-40 day important vegetative development period, and the 55-60 day flower bud differentiation period after the broccoli is planted in the mature stage, respectively, with a spraying time of 1.5-2 seconds per plant and a spraying amount of 18-20 L / ha.

[0063] Example 2-12

[0064] This embodiment provides a method for increasing the organic selenium content of broccoli, which is different from Embodiment 1 only in that the composite agent provided in Preparation Examples 2-12 is sprayed.

[0065] Comparative Example 1

[0066] This comparative example provides a method for increasing the organic selenium content of broccoli, which is different from Example 1 only in that the composite agent provided in Comparative Preparation Example 1 is sprayed.

[0067] Test Example 1

[0068] This test example uses the methods provided in Examples 1-12 and Comparative Example 1 to treat broccoli, and sets up a blank control at the same time. Normal management is performed without spraying the composite agent, and the organic selenium content of the curd and leaves with the maximum biomass at maturity is determined. The sample plants are mixed and sampled separately, and 3 replicates are taken for each sample, and 5 plants are sampled for each replicate. One leaf each from the upper, middle and lower parts are taken, and then mixed and operated according to the pre-treatment process for determination. The curd is a mature curd with a diameter of 15-16 cm, and the corresponding organic selenium content is determined after cutting and crushing (GB 5009.93-2017 Method 1). Table 2 shows the results of the determination of the organic selenium content after treating B1 broccoli, Table 3 shows the results of the determination of the organic selenium content after treating B3 broccoli, and Table 4 shows the results of the determination of the organic selenium content after treating "cold-resistant and excellent" broccoli (the main domestic variety from Japan), and the unit is μg / kg FW. The HPLC spectrum of the content of organic selenium components in broccoli curds is shown as follows Figure 1 shown.

[0069] Table 2

[0070]

[0071]

[0072] Table 3

[0073] B3 blade Flower Balls Example 1 2883.6 3010.3 Example 2 2459.3 2561.4 Example 3 2420.7 2538.4 Example 4 41.84 44.32 Example 5 1099.2 1120.5 Example 6 1999.2 2025.6 Example 7 1128.6 1213.9 Example 8 1817.3 1884.1 Example 9 1286.2 1347 Example 10 1254.8 1305.9 Embodiment 11 2687.3 2749.1 Example 12 2386.7 2447.6 Comparative Example 1 76.7 82.1 Blank control 30.54 32.49

[0074] Table 4

[0075] blade Flower Balls Example 1 1996.2 2005.8 Example 2 1603.8 1614.3 Example 3 1532.9 1542.2 Example 4 34.2 39.7 Example 5 658.1 662.4 Example 6 1432.0 1438.5 Example 7 653.2 662.4 Example 8 1369.1 1375.2 Example 9 687.0 693.6 Example 10 653.9 661.7 Embodiment 11 1876.9 1886.9 Example 12 1755.4 1764.0 Comparative Example 1 48.5 52.6 Blank control 28.33 29.14

[0076] It can be seen from Table 2, Table 3 and Table 4 that:

[0077] (1) Compared with the blank control, the organic selenium content in the florets and leaves of the broccoli in the experimental group using nanocarbon sol was significantly increased, up to 3010.3 μg / kg FW, which was about 92 times higher than that in the blank control group. The degree of increase was related to the type of broccoli. The ability to synthesize organic selenium varied greatly among different genotypes and broccoli strains, and broccoli B3 had a stronger ability to enrich selenium.

[0078] (2) By comparing Example 1, Example 4 and Comparative Example 1, it can be seen that the nanocarbon sol and selenite have a synergistic effect of increasing the organic selenium content in broccoli florets and leaves. The lack of any one of the components will reduce the organic selenium content. The synergy of the two can increase the organic selenium content by about 40 times compared with Comparative Example 1 and about 60 times compared with Example 4.

[0079] (3) Comparison of Example 1, Example 5 and Example 6 shows that too high or too low a content of selenite will lead to a decrease in the content of organic selenium in broccoli florets and leaves;

[0080] (4) By comparing Example 1, Example 7 and Example 8, it can be seen that too high or too low solid content of nano-scale carbon in the nanocarbon sol will lead to a decrease in the organic selenium content in the broccoli florets and leaves;

[0081] (5) By comparing Example 1, Example 9 and Example 10, it can be seen that a volume ratio of the nanocarbon sol to the sodium selenite solution that is too large or too small will lead to a decrease in the organic selenium content in the broccoli florets and leaves;

[0082] (6) Comparison of Example 1, Example 11 and Example 12 shows that selenite ion is an effective component in the selenite solution that promotes the increase of organic selenium content in broccoli florets and leaves.

[0083] In this test example, the methods provided in Examples 1-12 and Comparative Example 1 were used to treat B1 broccoli. A blank control was set up at the same time. Normal management was performed without spraying the composite agent. The protein content of the curd and leaves with the maximum biomass at maturity was determined by the third method of GB 5009.5-2016. The protein content (%) is shown in Table 5.

[0084] Table 5

[0085]

[0086]

[0087] Broccoli is rich in protein, especially the main amino acids for coupling free selenium: cysteine ​​and methionine. The protein content in the fresh curd of broccoli B1 in the present invention is as high as 4.2%. Compared with the control, the protein in both the leaves and curds of broccoli is significantly increased. The content of the nanocarbon sol and selenium dosage is increased by 7.2%-31.3%, and the average water content in the leaves and curds is 89%-90%. After freeze-drying or enzymatic hydrolysis into polypeptides, the protein and polypeptide content is generally greater than 40%, which provides natural raw materials and scientific and technological support for the industrial use of broccoli curds and leaves (protein content is similar to that in curds). It also enhances the ecological and technological support for the big food view and the transformation of agricultural tail vegetables into high-quality protein. It is a powerful scientific and technological support for new quality productivity, and will also provide domestic and industry models for front-line transformation, and also provide scientific research directions and research foundations for my country's carbon peak, carbon neutral agriculture, ecology and common technology planning.

[0088] In summary, the present invention provides a nano carbon sol, and further preferably a composite agent containing nano carbon sol and selenite solution, by spraying the composite agent on broccoli and detecting and analyzing the coupling products at different periods (HPLC), the content of organic selenium can be significantly increased, and the degree of increase is related to the variety of broccoli. The nano carbon sol can be widely used on cruciferous crops, significantly improving the ability to synthesize organic selenium and protein content, especially for broccoli B3 similar resources, it has outstanding selenium enrichment ability, which is dozens or even hundreds of times higher than ordinary varieties, and has extremely broad industrial development and market prospects, providing a natural biological factory and technical process for the industrial development of broccoli.

[0089] The applicant declares that the above is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention are within the protection scope and disclosure scope of the present invention.

Claims

1. Application of nanocarbon sol in coupling free selenium to increase the organic selenium content and / or protein content of broccoli.

2. The use according to claim 1, characterized in that: The solid content of nano-scale carbon in the nano-carbon sol is 0.2-0.8wt%, preferably 0.4-0.6wt%; Preferably, the particle size of the nanoscale carbon in the nanocarbon sol is 0.1 to 200 nm, preferably 1 to 6 nm; Preferably, the pH of the nanocarbon sol is 2 to 4; Preferably, the content of nano-scale carbon in the nano-carbon sol is more than 95.5%.

3. The use according to claim 1 or 2, characterized in that: The method of increasing the organic selenium content of broccoli specifically includes increasing the organic selenium content of any one of the broccoli head, leaves, main stem, flower stalk, flower bud or seeds, or a combination of at least two of the broccoli heads, leaves, main stem, flower stalks, flower buds or seeds.

4. The use according to any one of claims 1 to 3, characterized in that: The broccoli includes the hybrid Zhongqing 15 and / or the female parent of the hybrid Zhongqing 15.

5. The use according to any one of claims 1 to 4, characterized in that: The organic selenium includes any one of selenocysteine, methylselenocysteine ​​or selenomethionine, or a combination of at least two of them.

6. A composite agent for increasing the organic selenium content and / or protein content of broccoli, characterized in that: The composite agent contains nano carbon sol.

7. The composite agent according to claim 6, characterized in that The solid content of nano-scale carbon in the nano-carbon sol is 0.2-0.8 wt %, preferably 0.4-0.6 wt %.

8. The composite agent according to claim 6 or 7, characterized in that: The composite agent also contains a selenite solution; Preferably, the selenite includes any one of sodium selenite, potassium selenite, sodium hydrogen selenite or potassium hydrogen selenite, or a combination of at least two thereof; Preferably, the concentration of the selenite solution is 0 to 300 mg / L, preferably 180 to 220 mg / L; Preferably, the volume ratio of the nanocarbon sol to the selenite solution in the composite is 1:(0-3), preferably 1:(0.3-0.5).

9. A method for increasing the organic selenium content and / or protein content of broccoli, characterized in that: The method comprises: spraying the composite agent according to any one of claims 6 to 8 onto broccoli.

10. The method according to claim 9, characterized in that The method specifically comprises: spraying the composite agent once during the 25-30 day nutrient development period, the 35-40 day important nutrient development period and the 55-60 day flower bud differentiation period after the broccoli is planted; Preferably, the spraying amount of the composite agent is 1 to 20 L / ha, preferably 18 to 20 L / ha.

Images