Method for simultaneously preparing high-purity pasty chlorophyll and 1-deoxynojirimycin and product thereof

Abstract

The invention provides a method for simultaneously preparing high-purity pasty chlorophyll and 1-deoxynojirimycin and a product thereof. The method specifically comprises the following steps: taking fresh silkworm excrement dried to a certain moisture as a raw material, and extracting by adopting a mixed solvent to obtain an extracting solution; carrying out centrifugal separation on the extracting solution to respectively obtain a light phase containing chlorophyll and a heavy phase containing 1-deoxynojirimycin; carrying out refined filtration and vacuum concentration on the light phase to obtain high-purity pasty chlorophyll; and carrying out refined filtration, concentration, blending and spray drying on the heavy phase to obtain the 1-deoxynojirimycin with the concentration of 3% or above. According to the method, the mode of mixed extraction of the polar solvent and the non-polar solvent is adopted for the first time, and the chlorophyll extraction rate is increased by means of the penetrating power of the polar solvent and the dissolving power of the non-polar solvent to the target object; meanwhile, the polar solvent also completes the extraction of another polar substance 1-deoxynojirimycin. Besides, in the centrifugal separation process of the extracting solution, the separation of the two products is realized, and the dehydration process of the pasty chlorophyll is also realized.

Description

Technical Field

[0001] The invention belongs to the technical field of food additive refining, and particularly relates to a method for simultaneously preparing high-purity paste chlorophyll and 1-deoxynojirimycin and a product thereof. Background Art

[0002] Silkworm excrement is the excrement of silkworms after eating mulberry leaves. It is not only rich in crude protein and carbohydrates, but also can be used to extract chlorophyll, lutein, carotenoids, phytol, leaf protein, pectin, 1-deoxynojirimycin, etc., and can be widely used in food, medicine, feed and daily chemicals. Literature shows that the chlorophyll content in silkworm excrement is as high as 0.8-1.2%.

[0003] Existing literatures such as "The Effect of Different Solvents on the Extraction of Chlorophyll from Silkworm Excrement", "Research on the Extraction Technology of Chlorophyll from Silkworm Excrement", "Research on the Extraction and Properties of Chlorophyll from Silkworm Excrement", "Research on Process Parameters for Ultrasonic-Assisted Extraction of Chlorophyll from Silkworm Excrement", and "Research on the Utilization of Mixed Solvent Ultrasonic Extraction of Chlorophyll from Silkworm Excrement and Residues_Li Jing" have reported in detail on the extraction solvents and methods of chlorophyll from silkworm excrement; "The Application of Countercurrent Technology Equipment in Extracting Chlorophyll from Silkworm Excrement" and "A Method for Continuously Extracting Chlorophyll from Silkworm Excrement" and other scientific and technological achievements introduced the method of extracting chlorophyll from silkworm excrement using continuous countercurrent extraction. The above methods and solvents have achieved certain effects on the extraction of chlorophyll from silkworm excrement.

[0004] As is known to all, silkworm excrement contains a variety of active substances, all of which have a wide range of application markets. However, the prior art for the extraction of silkworm excrement is still limited to obtaining a single component. In actual production, more attention is paid to the extraction efficiency and quality of a single component, while the comprehensive development of multiple substances is ignored. The prior art has not disclosed a method for the comprehensive extraction of two or more components in silkworm excrement at the same time with high efficiency and high quality.

[0005] In summary, providing a method for comprehensive development and utilization of silkworm excrement is an urgent problem to be solved by those skilled in the art. Summary of the invention

[0006] The purpose of the present invention is to provide a method for simultaneously preparing high-purity paste chlorophyll and 1-deoxynojirimycin. The technical solution provided by the present invention uses fresh silkworm excrement with a specific water content as raw material, adopts a mixed extraction method of polar solvent and non-polar solvent, and simultaneously obtains chlorophyll and 1-deoxynojirimycin in the same extract; the extract is then centrifuged to obtain a light phase containing chlorophyll and a heavy phase containing 1-deoxynojirimycin; after fine filtration and reduced pressure concentration of the light phase, a paste chlorophyll product with a content of more than 27% can be obtained, and its extraction rate is more than 95%, and the average yield reaches 0.59%; the 1-deoxynojirimycin contained in the heavy phase also achieves the removal of fat-soluble impurities during the stratification process, and after separation, concentration and drying, a water-soluble 1-deoxynojirimycin powder product with a content of more than 3% can be obtained, and the average yield is 2.88%.

[0007] The technical solution provided by the present invention, through the design of solvent and extraction process, can simultaneously and efficiently extract chlorophyll and 1-deoxynojirimycin using fresh silkworm excrement as raw material and only one mixed extractant. Compared with the prior art, the content of paste chlorophyll is improved, providing high-quality raw materials for the preparation of microencapsulated chlorophyll, oil-soluble copper chlorophyll and sodium copper chlorophyll; at the same time, high-quality water-soluble 1-deoxynojirimycin is obtained, providing a new idea and effective method for the comprehensive development and utilization of silkworm excrement.

[0008] To achieve the above object, the present invention provides a method for simultaneously preparing high-purity paste-like chlorophyll and 1-deoxynojirimycin, comprising the following steps:

[0009] (1) Drying the fresh silkworm excrement in a cool place until the moisture content reaches a certain level;

[0010] (2) putting the dried silkworm litter into an extraction tank, adding an extraction solvent, stirring and extracting in a water bath, filtering, and obtaining a mixed solution; wherein the extraction solvent is composed of a non-polar solvent and a polar solvent;

[0011] (3) subjecting the obtained mixed solution to coarse filtration to obtain a coarse filtrate;

[0012] (4) centrifuging the obtained crude filtrate to obtain a light phase containing chlorophyll and a heavy phase containing 1-deoxynojirimycin;

[0013] (5) The light phase containing chlorophyll is finely filtered and concentrated to obtain a high-purity paste-like chlorophyll; the heavy phase containing 1-deoxynojirimycin is finely filtered, concentrated, blended, and spray-dried to obtain 1-deoxynojirimycin.

[0014] In a preferred embodiment, in step (1), the moisture content of the silkworm excrement after the air-drying treatment is 40-60%. At present, the traditional way to process silkworm excrement is to reduce the moisture content to below 20% by air-drying or sun-drying to facilitate long-term storage, and then soften the silkworm excrement by adding water to 40-60% before extraction. However, the air-drying of silkworm excrement and the softening treatment before extraction both take a long time, and the treatment process will generate heat, resulting in chlorophyll loss; in addition, reducing the moisture content first and then adding water to soften it leads to repeated processes and increased costs. In the present invention, the fresh silkworm excrement is first dried to 40-60% moisture, and then directly extracted and produced, which not only simplifies the process, but also reduces the loss of effective ingredients.

[0015] In a preferred embodiment, in step (2), the mass ratio of the non-polar solvent to the polar solvent is (1-10):1. Preferably, the mass ratio of the non-polar solvent to the polar solvent is (2-6):1.

[0016] In a preferred embodiment, in step (2), the non-polar solvent includes an ether solvent and / or an alkane solvent; and the polar solvent is a small molecule alcohol.

[0017] In a preferred embodiment, in step (2), the non-polar solvent includes one or more of petroleum ether, diethyl ether, methyl tert-butyl ether and alkane solvents with 4 to 7 carbon atoms; the polar solvent includes one or more of methanol, ethanol and isopropanol.

[0018] In a preferred embodiment, in step (2), the solid-liquid ratio of the silkworm excrement to the extraction solvent is 1:(2-20); preferably, the solid-liquid ratio of the silkworm excrement to the extraction solvent is 1:(3-10).

[0019] In a preferred embodiment, in step (2), the water bath temperature is 30-60°C; the extraction time is 0.5-5h; preferably, the water bath temperature is 40-60°C; the extraction time is 2-4h.

[0020] In a preferred embodiment, in step (2), the number of extractions is 1 to 8 times; preferably, only the mixed solution after the first extraction is used for coarse filtration in step (3), and the mixed solution after the remaining extractions can be used for extraction solvent. After the non-polar solvent and the polar solvent are supplemented in proportion, other batches of fresh silkworm excrement can be extracted, thereby avoiding the generation of waste liquid.

[0021] In a preferred embodiment, in step (3), the mesh size of the coarse filtration device is 100 to 500 meshes, and the specific device can adopt conventional devices known to those skilled in the art, such as pipeline filtration, leaf filters, bag filters, etc.; preferably, the mesh size of the coarse filtration device is 300 to 500 meshes.

[0022] In a preferred embodiment, in step (4), the centrifugal separation device includes a disc centrifuge, a tubular centrifuge, a horizontal screw centrifuge, or other explosion-proof centrifuge suitable for liquid-liquid two-phase separation containing organic solvents.

[0023] In a preferred embodiment, in step (5), the mesh number of the fine filtration device for the chlorophyll-containing light phase is 500-1500 mesh, and the specific device can adopt conventional devices known to those skilled in the art, such as bag-type, paperboard, plate and frame filters, etc.; preferably, the mesh number of the fine filtration device for the chlorophyll-containing light phase is 800-1200 mesh.

[0024] In a preferred embodiment, in step (5), the concentration conditions of the chlorophyll-containing fine filtrate include: concentration temperature 40 to 70°C, concentration pressure: -0.02 to -0.09Mpa, and concentration until the residual volume of the solvent in the chlorophyll-containing light phase is less than 1%; preferably, the concentration conditions of the chlorophyll-containing fine filtrate include: concentration temperature 60 to 70°C, concentration pressure: -0.04 to -0.09Mpa.

[0025] In a preferred embodiment, in step (5), the content of the prepared high-purity paste chlorophyll is above 27%, the extraction rate is above 95%, and the average yield reaches 0.59%.

[0026] In a preferred embodiment, in step (5), the mesh number of the fine filtration device for the heavy phase containing 1-deoxynojirimycin is 500-1500 mesh, and the specific device can adopt conventional devices known to those skilled in the art, such as bag-type, paperboard, plate and frame filters, etc.; preferably, the mesh number of the fine filtration device for the heavy phase containing 1-deoxynojirimycin is 800-1200 mesh.

[0027] In a preferred embodiment, in step (5), the concentration conditions of the 1-deoxynojirimycin-containing filtrate include: concentration temperature 40 to 100°C, concentration pressure: -0.02 to -0.09 MPa, and concentration to a Brix of 10 to 40%; preferably, the concentration conditions of the 1-deoxynojirimycin-containing filtrate include: concentration temperature 60 to 90°C, concentration pressure: -0.06 to -0.09 MPa, and concentration to a Brix of 20 to 30%.

[0028] In a preferred embodiment, in step (5), the auxiliary materials prepared include one or more of maltodextrin, gum arabic, and modified starch, and the amount of the auxiliary materials prepared is 5-20% of the mass of the concentrated solution containing 1-deoxynojirimycin.

[0029] In a preferred embodiment, in step (5), the spray drying conditions of the prepared liquid containing 1-deoxynojirimycin include: an air inlet temperature of 160-220°C, and an air outlet temperature of 80-120°C; preferably, the spray drying conditions of the prepared liquid containing 1-deoxynojirimycin include: an air inlet temperature of 180-210°C, and an air outlet temperature of 90-120°C.

[0030] In a preferred embodiment, in step (5), the content of the prepared 1-deoxynojirimycin is above 3%, and the average yield is 2.88%.

[0031] In a preferred embodiment, in step (5), there is no particular order in which the high-purity chlorophyll paste and 1-deoxynojirimycin are prepared. Preparing the high-purity chlorophyll paste first or preparing 1-deoxynojirimycin first is within the scope of protection of the present invention.

[0032] Another object of the present invention is to provide high-purity paste-like chlorophyll and / or 1-deoxynojirimycin prepared by any of the above methods.

[0033] Compared with the prior art, the technical solution of the present invention has the following advantages:

[0034] In the present invention, a mixed extraction method of polar solvent and non-polar solvent is adopted, which not only improves the extraction rate of chlorophyll by virtue of the penetration ability of polar solvent and the solubility of non-polar solvent on the target object; at the same time, the polar solvent also completes the extraction of another polar substance 1-deoxynojirimycin, achieving the purpose of comprehensive development. In addition, during the centrifugal separation of the extract, not only the separation of the two products is achieved, but also the dehydration process of the paste chlorophyll is achieved. The chlorophyll after stratification exists in the non-polar solvent. After the solvent is recovered, a high-purity paste chlorophyll can be obtained without the need for additional dehydration treatment.

[0035] In the present invention, fresh silkworm excrement is used as raw material for the first time, and is air-dried to a specific moisture content, and extracted with a polar solvent and a non-polar solvent. The obtained extract is coarsely filtered and then centrifuged to simultaneously obtain a chlorophyll extract and a 1-deoxynojirimycin extract; the chlorophyll extract separation liquid is finely filtered and concentrated to obtain a paste-like chlorophyll product with a content of more than 27%, a chlorophyll extraction rate of more than 95%, and an average yield of 0.59%; the 1-deoxynojirimycin extract separation liquid is finely filtered, concentrated, formulated, and dried to obtain a 1-deoxynojirimycin powder product with a content of more than 3%, and the average yield of the product is 2.88%.

[0036] The overall process of the present invention is simple and efficient, eliminating the process of softening silkworm excrement and solving the problem that the paste chlorophyll in the traditional process needs to be additionally dehydrated, which not only shortens the operation time but also effectively improves the yield of the paste chlorophyll. Through the one-step extraction method with the same solvent, two products are obtained at the same time, which improves the application value of silkworm excrement and provides an effective solution for the comprehensive development and utilization of silkworm excrement. DETAILED DESCRIPTION

[0037] In order to enable those skilled in the art to better understand the present invention, the present invention is further described in detail below in conjunction with specific implementation methods, but it should be understood that the protection scope of the present invention is not limited by the specific implementation methods.

[0038] The embodiment of the present invention solves the problems in the prior art of complex process, low product purity, low raw material utilization rate, and inability to obtain two high-quality products in the same process by providing a method for simultaneously preparing high-purity paste chlorophyll and 1-deoxynojirimycin and a product thereof.

[0039] The technical solution of the present application is described in detail below through specific embodiments:

[0040] Unless otherwise specified, the technical means used in the present invention are conventional means well known to those skilled in the art, and the various raw materials, reagents, instruments and equipment used in the present invention can be purchased from the market or prepared by existing methods. The reagents used in the present invention are analytically pure unless otherwise specified.

[0041] Example 1

[0042] (1) The moisture content of fresh silkworm excrement after drying was 55.7%. After testing, the chlorophyll content was 0.570% and the 1-deoxynojirimycin content was 1.084‰.

[0043] (2) 500 kg of fresh silkworm excrement treated in step (1) is put into an extraction tank, 500 kg of 95% ethanol and 2000 kg of vegetable oil extraction solvent are added, and the mixture is stirred and extracted 4 times at 58° C., each time for 2 hours. The extract from the first extraction is filtered through a 500-mesh pipeline filter to obtain a coarse filtrate; after extraction, the silkworm excrement residue is 0.04%, the water content is 26.64%, and the extraction rate is 95.93%. The extracts from the second to fourth extractions are used for the extraction of other batches of fresh silkworm excrement.

[0044] (3) extracting the crude filtrate and separating it using a liquid-liquid two-phase disc separator to obtain a vegetable oil extraction solvent phase containing chlorophyll and an ethanol phase containing 1-deoxynojirimycin;

[0045] (4) filtering the chlorophyll-containing vegetable oil extraction solvent phase through an 800-mesh bag filter to obtain a chlorophyll-containing fine filtrate; concentrating the fine filtrate at 58 to 65° C. and -0.06 to -0.07 MPa to a solvent residual content of less than 1%, to obtain 9.54 kg of chlorophyll paste with a chlorophyll content of 28.63% and a yield of 0.546%;

[0046] (5) filtering the ethanol phase containing 1-deoxynojirimycin using a 1000-mesh plate-and-frame filter to obtain a refined filtrate containing 1-deoxynojirimycin; concentrating the refined filtrate to a Brix of 22.40% at 75 to 80° C. and -0.07 to -0.08 MPa to obtain 54.79 kg of a concentrated solution having a 1-deoxynojirimycin content of 0.92%;

[0047] (6) Adding maltodextrin in an amount of 6.57% by weight of the concentrate, stirring at 80° C. until completely dissolved and mixed uniformly, to obtain a 1-deoxynojirimycin formulation; spray drying the formulation at an air inlet temperature of 180 to 190° C. and an air outlet temperature of 80 to 90° C. to obtain 15.96 kg of 1-deoxynojirimycin powder with a content of 3.09% and a yield of 3.19%.

[0048] Example 2

[0049] (1) The moisture content of fresh silkworm excrement after drying was 45.3%. After testing, the chlorophyll content was 0.645% and the 1-deoxynojirimycin content was 0.936‰.

[0050] (2) 500 kg of fresh silkworm excrement treated in step (1) is put into an extraction tank, 800 kg of anhydrous methanol and 2400 kg of petroleum ether are added, and the mixture is stirred and extracted 5 times at 54° C., each time for 2 hours. The extract from the first extraction is filtered through a 500-mesh pipeline filter to obtain a coarse filtrate; after extraction, the silkworm excrement residue is 0.03%, the water content is 21.3%, and the extraction rate is 96.77%. The extracts from the 2nd to 5th extractions are used for the extraction of other batches of fresh silkworm excrement.

[0051] (3) extracting the crude filtrate and separating it using a liquid-liquid two-phase disc separator to obtain a petroleum ether phase containing chlorophyll and a methanol phase containing 1-deoxynojirimycin;

[0052] (4) filtering the petroleum ether phase containing chlorophyll through a 1000-mesh plate-frame filter to obtain a chlorophyll-containing fine filtrate; concentrating the fine filtrate at 55 to 60° C. and -0.07 to -0.08 MPa to a solvent residual content of less than 1%, to obtain 9.84 kg of chlorophyll paste with a chlorophyll content of 31.45% and a yield of 0.619%;

[0053] (5) filtering the methanol phase containing 1-deoxynojirimycin through an 800-mesh cardboard filter to obtain a refined filtrate containing 1-deoxynojirimycin; concentrating the refined filtrate to a Brix of 25.76% at 73 to 78° C. and -0.07 to -0.08 MPa to obtain 35.1 kg of a concentrated solution having a 1-deoxynojirimycin content of 1.28%;

[0054] (6) Gum arabic and maltodextrin (weight ratio of 1:3) were added to the concentrate in an amount of 15.67% of the weight of the concentrate, and the mixture was stirred at 80° C. until completely dissolved and mixed uniformly to obtain a 1-deoxynojirimycin preparation solution; the preparation solution was spray-dried at an air inlet temperature of 185 to 195° C. and an air outlet temperature of 85 to 95° C. to obtain 14.1 kg of 1-deoxynojirimycin powder with a content of 3.14% and a yield of 2.82%.

[0055] Example 3

[0056] (1) The moisture content of fresh silkworm excrement after drying was 53.2%. After testing, the chlorophyll content was 0.628% and the 1-deoxynojirimycin content was 0.899‰.

[0057] (2) 500 kg of fresh silkworm excrement treated in step (1) is put into an extraction tank, 600 kg of 90% methanol and 1800 kg of vegetable oil extraction solvent are added, and the mixture is stirred and extracted 4 times at 60° C., each time for 3 hours. The extract from the first extraction is filtered through a 500-mesh pipeline filter to obtain a coarse filtrate; after extraction, the silkworm excrement residue is 0.05%, the water content is 24.1%, and the extraction rate is 95.09%. The extracts from the 2nd to 4th extractions are used for the extraction of other batches of fresh silkworm excrement.

[0058] (3) extracting the crude filtrate and separating it using a liquid-liquid two-phase disc separator to obtain a vegetable oil extraction solvent phase containing chlorophyll and a methanol phase containing 1-deoxynojirimycin;

[0059] (4) filtering the chlorophyll-containing vegetable oil extraction solvent phase through a 1000-mesh plate-frame filter to obtain a chlorophyll-containing fine filtrate; concentrating the fine filtrate at 55 to 60° C. and -0.07 to -0.08 MPa to a solvent residual content of less than 1%, to obtain 10.90 kg of chlorophyll paste, with a chlorophyll content of 27.84% and a yield of 0.607%;

[0060] (5) filtering the methanol phase containing 1-deoxynojirimycin through a 1200-mesh bag filter to obtain a refined filtrate containing 1-deoxynojirimycin; concentrating the refined filtrate to a Brix of 18.27% at 75 to 80° C. and -0.07 to -0.08 MPa to obtain 54.1 kg of a concentrated solution containing 0.79% 1-deoxynojirimycin;

[0061] (6) adding modified starch to the concentrated solution in an amount of 6.47% by weight of the concentrated solution, stirring at 80° C. until completely dissolved and mixed evenly to obtain a 1-deoxynojirimycin preparation solution; spray drying the preparation solution at an air inlet temperature of 190 to 195° C. and an air outlet temperature of 90 to 100° C. to obtain 13.1 kg of 1-deoxynojirimycin powder with a content of 3.20% and a yield of 2.63%.

[0062] Comparative Example 1

[0063] (1) The moisture content of fresh silkworm excrement after drying is 53.2%. After testing, the chlorophyll content is 0.628%.

[0064] (2) 500 kg of fresh silkworm excrement treated in step (1) is put into an extraction tank, 2500 kg of 97% acetone solvent is added, and the mixture is stirred and extracted 4 times at 45° C., each time for 2 hours. The extract from the first extraction is filtered through a 500-mesh pipeline filter to obtain a coarse filtrate; after extraction, the silkworm excrement residue is 0.12%, the water content is 24.1%, and the extraction rate is 88.65%.

[0065] (3) filtering the chlorophyll-containing coarse filtrate using a 1000-mesh bag filter to obtain a chlorophyll-containing fine filtrate; concentrating the fine filtrate to an acetone concentration of less than 10% at 55 to 60° C. and -0.07 to -0.08 MPa to obtain a concentrated solution;

[0066] (4) The concentrate was allowed to stand at room temperature and the lower aqueous phase was slowly discharged. The upper ointment phase was transferred to a dehydration tank and dehydrated under reduced pressure at 60 to 65° C. and -0.08 to -0.09 MPa for 3.5 hours to obtain 21.08 kg of chlorophyll paste with a chlorophyll content of 12.38% and a yield of 0.522%;

[0067] Comparative Example 2

[0068] (1) The moisture content of fresh silkworm excrement after drying is 53.2%. After testing, the chlorophyll content is 0.628%.

[0069] (2) After drying to a moisture content of 14.36%, 320 kg of dry silkworm excrement was obtained, with a chlorophyll content of 0.891%.

[0070] (3) After adding 200 kg of water to the dry silkworm excrement and stirring to mix, the mixture was placed at room temperature to soften for 4 h, and then put into an extraction tank, 3000 kg of 97% acetone solvent was added, and the mixture was stirred and extracted at 42° C. for 4 times, each time for 2 h. The extract from the first extraction was filtered through a 500-mesh pipeline filter to obtain a coarse filtrate. After extraction, the silkworm excrement residue was 0.09%, the water content was 19.7%, and the extraction rate was 89.23%.

[0071] (4) filtering the chlorophyll-containing coarse filtrate using an 800-mesh bag filter to obtain a chlorophyll-containing fine filtrate; concentrating the fine filtrate to an acetone concentration of less than 10% at 55 to 60° C. and -0.07 to -0.08 MPa to obtain a concentrated solution;

[0072] (5) The concentrate was allowed to stand at room temperature and the lower aqueous phase was slowly discharged. The upper ointment phase was transferred to a dehydration tank and dehydrated under reduced pressure at 60 to 65° C. and -0.08 to -0.09 MPa for 4 h to obtain 23.13 kg of chlorophyll paste with a chlorophyll content of 10.96% and a yield of 0.507%;

[0073] Table 1 Comparison of analytical test results of Examples 1 to 3 and Comparative Examples 1 to 2.

[0074]

[0075] According to the results in Table 1, we can see that:

[0076] (1) The water content of the chlorophyll paste in the embodiment is 29.35-32.39%, and the average content is 30.51%, which is 91.05% higher than that in Comparative Example 1 and 106.99% higher than that in Comparative Example 2;

[0077] (2) The chlorophyll extraction rate of the embodiment is 95.09-96.77%, and the average extraction rate reaches 95.93%, which is 8.21% higher than that of Comparative Example 1 and 7.51% higher than that of Comparative Example 2;

[0078] (3) Example 3 and Comparative Examples 1 and 2 use the same batch of fresh silkworm excrement. Comparison shows that the yield of chlorophyll paste in Example 3 is 0.607%, which is 16.28% higher than that in Comparative Example 1 and 19.72% higher than that in Comparative Example 2.

[0079] (4) In Example 1-3, two products, namely, chlorophyll paste and 1-deoxynojirimycin with a 3% content, can be obtained simultaneously through mixed solvent extraction and subsequent processing, and the average yield of the 1-deoxynojirimycin product with a 3% content reaches 2.88%, while the comparative example only obtains one chlorophyll paste product.

[0080] Based on the above analysis results, it can be seen that the process of the embodiment of the present invention has obvious advantages in the extraction rate, yield, product content of paste chlorophyll, and comprehensive development and utilization of silkworm feces. The paste chlorophyll product produced by the present invention can be used to prepare microencapsulated chlorophyll, oil-soluble copper chlorophyll and sodium copper chlorophyll products; the 1-deoxynojirimycin product with a 3% content can be used in the fields of functional foods and the like.

[0081] The foregoing description of specific exemplary embodiments of the present invention is for the purpose of illustration and demonstration. These descriptions are not intended to limit the present invention to the precise form disclosed, and it is clear that many changes and variations can be made based on the above teachings. The purpose of selecting and describing the exemplary embodiments is to explain the specific principles of the present invention and its practical application, so that those skilled in the art can realize and utilize various different exemplary embodiments of the present invention and various different selections and changes. The scope of the present invention is intended to be limited by the claims and their equivalents.

Claims

1. A method for simultaneously preparing high-purity paste-like chlorophyll and 1-deoxynojirimycin, characterized in that: The following steps are involved: (1) Drying the fresh silkworm excrement in a cool place until the moisture content reaches a certain level; (2) putting the dried silkworm litter into an extraction tank, adding an extraction solvent, stirring and extracting in a water bath, filtering, and obtaining a mixed solution; wherein the extraction solvent is composed of a non-polar solvent and a polar solvent; (3) subjecting the obtained mixed solution to coarse filtration to obtain a coarse filtrate; (4) centrifuging the obtained crude filtrate to obtain a light phase containing chlorophyll and a heavy phase containing 1-deoxynojirimycin; (5) The light phase containing chlorophyll is finely filtered and concentrated to obtain a high-purity paste-like chlorophyll; the heavy phase containing 1-deoxynojirimycin is finely filtered, concentrated, blended, and spray-dried to obtain 1-deoxynojirimycin.

2. The method for simultaneously preparing high-purity paste chlorophyll and 1-deoxynojirimycin as claimed in claim 1, characterized in that: In step (1), the moisture content of the silkworm excrement after the drying process is 40-60%.

3. The method for simultaneously preparing high-purity paste chlorophyll and 1-deoxynojirimycin as claimed in claim 1, characterized in that: In step (2), the mass ratio of the non-polar solvent to the polar solvent is (1-10):

1.

4. The method for simultaneously preparing high-purity paste chlorophyll and 1-deoxynojirimycin as claimed in claim 3, characterized in that: In step (2), the non-polar solvent includes an ether solvent and / or an alkane solvent; and the polar solvent is a small molecule alcohol.

5. The method for simultaneously preparing high-purity paste chlorophyll and 1-deoxynojirimycin as claimed in claim 4, characterized in that: In step (2), the non-polar solvent includes one or more of petroleum ether, diethyl ether, methyl tert-butyl ether and alkane solvents with 4 to 7 carbon atoms; the polar solvent includes one or more of methanol, ethanol and isopropanol.

6. The method for simultaneously preparing high-purity paste chlorophyll and 1-deoxynojirimycin as claimed in claim 1, characterized in that: In step (2), the solid-liquid ratio of the silkworm excrement to the extraction solvent is 1:(2-20); the water bath temperature is 30-60° C.; and the extraction time is 0.5-5 h.

7. The method for simultaneously preparing high-purity paste-like chlorophyll and 1-deoxynojirimycin as claimed in claim 1, characterized in that: In step (5), the concentration conditions of the chlorophyll-containing filtrate include: concentration temperature 40 to 70° C., concentration pressure: -0.02 to -0.09 MPa.

8. The method for simultaneously preparing high-purity paste chlorophyll and 1-deoxynojirimycin as claimed in claim 1, characterized in that: In step (5), the concentration conditions of the filtrate containing 1-deoxynojirimycin include: concentration temperature 40 to 100° C., concentration pressure: -0.02 to -0.09 MPa, and concentration to a Brix of 10 to 40%.

9. The method for simultaneously preparing high-purity paste-like chlorophyll and 1-deoxynojirimycin as claimed in claim 1, characterized in that: In step (5), the content of the prepared 1-deoxynojirimycin is above 3%, and the average yield is 2.88%; the content of the prepared high-purity paste chlorophyll is above 27%, the extraction rate is above 95%, and the average yield reaches 0.59%.

10. High-purity paste-like chlorophyll and / or 1-deoxynojirimycin prepared by the method according to any one of claims 1 to 9.

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