Preparation method of bamboo and rhizoma polygonati feed additive based on betaine citric acid NaDES

Abstract

The invention relates to a preparation method of a bamboo and rhizoma polygonati feed additive based on betaine and citric acid NaDES, and belongs to the technical field of feed processing. The method comprises the following steps: mixing betaine and citric acid according to a specific molar ratio, and heating to prepare a NaDES solvent; then crushing the bamboos and the rhizoma polygonati into mixed powder according to a proportion; and finally, performing supramolecular extraction on the mixed powder by using a NaDES solvent, and performing centrifugal filtration to obtain an extracting solution. According to the method, plant cell walls are destroyed through the NaDES solvent, the extraction yield of active ingredients such as polysaccharide is remarkably increased, and the problems that a traditional water extraction or alcohol extraction method is low in efficiency and high in cost are solved. The obtained feed additive can effectively promote the growth of meat poultry and reduce the blood cholesterol level, is free of antibiotic residues, and is suitable for large-scale production. The method has the advantages of simple process, environmental protection, high extraction efficiency and the like.

Description

Technical Field

[0001] The present invention belongs to the technical field of feed additive preparation, and specifically relates to a method for extracting plant active ingredients based on supramolecular technology (natural deep eutectic solvent, NaDES), in particular to a method for efficiently extracting polysaccharide active ingredients from bamboo and polygonatum using betaine citrate NaDES solvent, and preparing the polysaccharide active ingredients as feed additives. Background Art

[0002] With the development of animal husbandry, feed additives play an increasingly significant role in improving animal growth performance, enhancing immunity and improving meat quality. At present, plant-derived feed additives have attracted much attention due to their advantages such as naturalness, safety and lack of drug resistance. Bamboo and Polygonatum sibiricum, as natural raw materials rich in bioactive ingredients such as polysaccharides, flavonoids and organic acids, have been gradually used in the field of animal feed.

[0003] Traditional methods for extracting active ingredients from plants mainly use water extraction or organic solvent (such as ethanol) extraction. For example, the water extraction method extracts the contents of plant cells by heating the aqueous solution, but it has problems such as low extraction efficiency (polysaccharide extraction yield is usually less than 20%), long time consumption, and easy degradation of active ingredients; although the ethanol extraction method can increase the yield of some fat-soluble components, it has limited extraction effect on water-soluble components such as polysaccharides, and there is a risk of solvent residue, which does not meet the requirements of green production. In addition, there have been attempts in the prior art to use bamboo powder, bamboo leaf extract or Polygonatum fermentation as feed additives, but their preparation process is complicated and the cost is high, making it difficult to meet the needs of large-scale production.

[0004] In recent years, natural deep eutectic solvent (NaDES) has been used in the food and pharmaceutical fields as a new type of green solvent due to its strong designability, high biocompatibility, and no toxic residue. However, there is no report in the prior art on the use of betaine citrate NaDES solvent for the extraction of active ingredients from bamboo and polygonatum and its direct use as a feed additive.

[0005] In summary, how to use green and efficient extraction technology to break through the limitations of traditional methods of low extraction efficiency of plant active ingredients, solvent residues and high preparation costs, and at the same time develop feed additives that have both growth-promoting and cholesterol-lowering functions, is still a technical problem that needs to be urgently solved in this field. Summary of the invention

[0006] In view of the existing technical problems, the purpose of the present invention is to provide a method for preparing a bamboo and polygonatum feed additive based on betaine citrate NaDES, which destroys the plant cell wall by NaDES solvent and significantly improves the extraction rate of active ingredients such as polysaccharides.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions: A preparation method of a bamboo and polygonatum sibiricum feed additive based on betaine citrate NaDES, comprising the following steps: S1: Prepare the betaine citrate NaDES solvent: Mix betaine and citric acid in a molar ratio of 1:0.2 - 4, stir and heat at 40 - 80 °C for 3 - 12 hours to form a viscous liquid; S2: Prepare the bamboo and polygonatum sibiricum mixed powder: Mix bamboo and polygonatum sibiricum in a mass ratio of 1:0.1 - 5 and then crush to a particle size ≤ 100 mesh; S3: Supramolecular extraction: Add the betaine citrate NaDES solvent with a concentration of 0.1 - 0.5 g / mL to the mixed powder in step S2, heat and stir at 50 - 80 °C for 1 - 4 hours, then centrifuge at 4000 - 12000 r / min for 5 - 30 minutes, and filter to obtain the supramolecular extract.

[0008] Preferably, in step S1, the molar ratio of betaine to citric acid is 1:0.5 - 4, the heating temperature is 50 - 70 °C, and the stirring time is 6 - 10 hours; in step S2, the mass ratio of bamboo to polygonatum sibiricum is 1:0.3 - 3; in step S3, the concentration of the betaine citrate NaDES solvent is 0.2 - 0.4 g / mL, the heating temperature is 60 - 80 °C, and the centrifugation speed is 8000 - 12000 r / min.

[0009] Preferably, in step S1, the molar ratio of betaine to citric acid is 1:1 - 3, the stirring temperature is 60 - 70 °C, and the stirring time is 8 - 10 hours; in step S3, the centrifugation time is 5 - 15 minutes.

[0010] The present invention also provides a feed additive, which is composed of the supramolecular extract prepared by the above method, and the polysaccharide extraction rate in the extract ≥ 49.58%.

[0011] Preferably, the additive is added to the meat poultry feed at 0.5 - 2% of the feed dry weight, so that the blood cholesterol level of live pigs ≤ 2.7 mmol / L and the daily average weight gain ≥ 0.61 kg.

[0012] The present invention also provides an application of the betaine citrate NaDES solvent in the preparation of a bamboo and polygonatum sibiricum feed additive, and the solvent is prepared from betaine and citric acid in a molar ratio of 1:0.2 - 4, and is used to break the plant cell wall to improve the polysaccharide extraction rate.

[0013] Due to the adoption of the above scheme, the beneficial effects of the present invention are as follows: 1. The extraction efficiency is significantly improved: By using the betaine citrate NaDES solvent to break the cell walls of bamboo and polygonatum sibiricum, the polysaccharide extraction rate ≥ 49.58%, which is 2.67 times that of the traditional water extraction method and 1.95 times that of the 70% ethanol extraction method, greatly improving the utilization rate of active ingredients.

[0014] 2. Green environmental protection and safety: The NaDES solvent is prepared from betaine and citric acid, which is non-toxic and residue-free, meeting the requirements of green production and avoiding the residue risk of traditional organic solvents.

[0015] 3. Excellent feed additive function: The obtained extract is used as a feed additive and added to poultry feed at 0.5 - 2%, which can increase the daily weight gain of live pigs by 0.61 - 0.67 kg, reduce the blood cholesterol level to 2.3 - 2.7 mmol / L, and at the same time reduce the disease incidence and improve the meat quality.

[0016] 4. Simplified process and scalability: The method steps are simple (solvent preparation, pulverization, extraction), without the need for complex equipment, and the parameter ranges are clear (such as molar ratio 1:0.2 - 4, centrifugal speed 4000 - 12000 r / min), which is suitable for industrial production. Specific implementation manners

[0017] The technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0018] Example 1 A method for preparing bamboo and polygonatum sibiricum feed additive based on betaine citric acid NaDES includes the following steps: S1: Prepare betaine citric acid NaDES solvent: Mix betaine and citric acid at a molar ratio of 1:0.5, put them into a reactor, stir and heat at 60°C for 8 hours to form a viscous liquid; S2: Prepare a bamboo and polygonatum sibiricum mixed powder: Mix bamboo and polygonatum sibiricum at a mass ratio of 1:0.3 and pulverize to a particle size of ≤100 mesh; S3: Supramolecular extraction: Add 0.2 g / mL of betaine citric acid NaDES solvent to the mixed powder, heat and stir at 60°C for 2 hours, then centrifuge at 5000 r / min for 15 minutes, and filter to obtain a supramolecular extract.

[0019] Test results: The polysaccharide extraction rate is 49.58% (see Table 1).

[0020] Example 2 A method for preparing bamboo and polygonatum sibiricum feed additive based on betaine citric acid NaDES includes the following steps: S1: Prepare betaine citric acid NaDES solvent: The molar ratio of betaine to citric acid is 1:4, and stir at 80°C for 3 hours; S2: The mass ratio of bamboo to polygonatum sibiricum is 1:5, and it is crushed to ≤100 mesh. S3: Add 0.5 g / mL of NaDES solvent, extract at 80 °C for 1 hour, and centrifuge at 12,000 r / min for 5 minutes.

[0021] Test result: The extraction rate of polysaccharide is 45.23%.

[0022] Example 3 A preparation method of a bamboo and polygonatum sibiricum feed additive based on betaine citrate NaDES includes the following steps: S1: Prepare betaine citrate NaDES solvent: molar ratio 1:0.2, stir at 40 °C for 12 hours; S2: The mass ratio of bamboo to polygonatum sibiricum is 1:0.1, and it is crushed to ≤100 mesh. S3: Add 0.1 g / mL of NaDES solvent, extract at 50 °C for 4 hours, and centrifuge at 4,000 r / min for 30 minutes.

[0023] Test result: The extraction rate of polysaccharide is 43.71%.

[0024] Comparative example 1: Water extraction method Bamboo and polygonatum sibiricum are crushed to ≤100 mesh according to the mass ratio of 1:0.3; Add pure water (solid-liquid ratio 100 mg / mL), extract at 60 °C for 2 hours, and centrifuge at 5,000 r / min for 15 minutes.

[0025] Test result: The extraction rate of polysaccharide is 18.56% (see Table 1).

[0026] Comparative example 2: Ethanol extraction method Bamboo and polygonatum sibiricum are crushed to ≤100 mesh according to the mass ratio of 1:0.3; Add 70% ethanol (solid-liquid ratio 100 mg / mL), extract at 60 °C for 2 hours, and centrifuge at 5,000 r / min for 15 minutes.

[0027] Test result: The extraction rate of polysaccharide is 25.37% (see Table 1).

[0028] Feed feeding experiment Add the extracts of Examples 1-3 and Comparative examples 1-2 to the pig feed at an addition amount of 0.3% - 0.8%, and raise for 76 days. The results are as follows (see Table 2 for details): Example group: The average daily weight gain is 0.61 - 0.67 kg, the blood cholesterol is 2.3 - 2.7 mmol / L, and no diseases occur; Comparative example group: The average daily weight gain is 0.50 - 0.53 kg, the blood cholesterol is 5.3 - 5.8 mmol / L, and some pigs show symptoms such as colds.

[0029] Table 1 Table 2 As can be seen from Table 2, this feed additive can reduce the cholesterol of live pigs by about 50%, significantly promote the growth and development of live pigs, improve the immunity of live pigs, reduce the feed-to-meat ratio, and improve the quality of live pig meat.

Claims

1. A preparation method of a bamboo and polygonatum sibiricum feed additive based on betaine citrate NaDES, characterized in that, Including the following steps: S1: Prepare betaine citrate NaDES solvent: Mix betaine and citric acid in a molar ratio of 1:0.2 - 4, stir and heat at 40 - 80 °C for 3 - 12 hours to form a viscous liquid; S2: Prepare bamboo and polygonatum sibiricum mixture powder: Mix bamboo and polygonatum sibiricum in a mass ratio of 1:0.1 - 5 and crush to a particle size ≤ 100 mesh; S3: Supramolecular extraction: Add betaine citrate NaDES solvent with a concentration of 0.1 - 0.5 g / mL to the mixture powder in step S2, heat and stir at 50 - 80 °C for 1 - 4 hours, then centrifuge at 4000 - 12000 r / min for 5 - 30 minutes, and filter to obtain the supramolecular extract.

2. The method according to claim 1, wherein: In step S1, the molar ratio of betaine to citric acid is 1:0.5 - 4, the heating temperature is 50 - 70 °C, and the stirring time is 6 - 10 hours; In step S2, the mass ratio of bamboo to polygonatum sibiricum is 1:0.3 - 3; In step S3, the concentration of betaine citrate NaDES solvent is 0.2 - 0.4 g / mL, the heating temperature is 60 - 80 °C, and the centrifugation speed is 8000 - 12000 r / min.

3. The method according to claim 2, wherein: In step S1, the molar ratio of betaine to citric acid is 1:1 - 3, the stirring temperature is 60 - 70 °C, and the stirring time is 8 - 10 hours; In step S3, the centrifugation time is 5 - 15 minutes.

4. A feed additive, characterized in that: Composed of the supramolecular extract prepared by any one of the methods according to claims 1 - 3, and the polysaccharide extraction yield in the extract is ≥ 49.58%.

5. The feed additive according to claim 4, wherein: The additive is added to the poultry feed at 0.5 - 2% of the dry weight of the feed, so that the blood cholesterol level of live pigs is ≤ 2.7 mmol / L and the average daily weight gain is ≥ 0.61 kg.

6. Application of betaine citric acid NaDES solvent in preparing bamboo and polygonatum sibiricum feed additive, characterized in that: The solvent is prepared from betaine and citric acid in a molar ratio of 1:0.2 - 4 and is used to break the plant cell wall to improve the polysaccharide extraction yield.

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