Method for extracting lutein from marigold flowers

Abstract

The invention discloses a method for extracting lutein from fresh marigold flowers. The method comprises the following steps: step 1) crushing the fresh marigold flowers; (2) breaking the wall of a solid fluid bed; step 3) separation; and 4) purifying. The xanthophyll is prepared by taking fresh marigold flowers as raw materials through crushing, solid fluid bed wall breaking, separation and purification.

Description

Technical Field

[0001] The invention relates to the field of natural plant extracts, and in particular to a method for extracting lutein from fresh marigold flowers. Background Art

[0002] Marigold is an annual herbaceous plant of the Asteraceae family, 50-150 cm tall. The stem is erect, sturdy, with thin longitudinal ridges, and the branches spread upward. The leaves are pinnate, 5-10 cm long and 4-8 cm wide, with oblong or lanceolate lobes and sharp serrations on the edges.

[0003] Marigold lutein, its chemical formula is C 40 H 56 0 2 , the low-temperature extraction technology of marigold lutein is to use subcritical solvent low-temperature extraction, and the product obtained by the subcritical low-temperature extraction process is lutein ointment. The yield of trans-lutein, an effective ingredient indicator in the ointment, is relatively high, which can effectively reduce resource waste. In the existing patent (202311441486.8), marigold flowers contain lutein, and marigold flowers are dried, crushed, and solvent extracted to obtain crude marigold yellow pigment. The drying process causes lutein to be easily oxidized, reducing its yield. When the solvent is extracted for enzymatic hydrolysis, the enzymatic hydrolysis effect of marigold flowers in the solvent for enzymatic hydrolysis is not good, and the enzymatic hydrolysis effect generally reaches 50%, which is not conducive to the release of marigold yellow pigment from marigold flower cells. And the solvent residue is high, and subsequent refining is difficult, and the conventional marigold flower fermentation is that the flowers are directly put into the cement pool, and the fermentation time is about 15 days or more. The long fermentation time leads to low production efficiency. Summary of the invention

[0004] The invention aims to provide a method for extracting lutein from fresh marigold flowers. Fresh marigold flowers are used as raw materials, and lutein is obtained through crushing, solid fluidized bed wall breaking, separation and purification.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0006] A method for extracting lutein from fresh marigold flowers comprises the following steps:

[0007] Step 1) Crush the marigold flowers:

[0008] After picking, fresh marigold flowers are crushed in a crusher;

[0009] Step 2) Solid fluidized bed wall breaking:

[0010] The solid fluidized bed is composed of multiple fermentation units connected together, and each fermentation unit includes a fermentation tank and a centrifuge;

[0011] Yeast and cellulase liquid are added to the fermentation tank of each fermentation unit, the crushed marigold flowers are first fermented in the fermentation tank of the first fermentation unit and then centrifuged in a centrifuge, and the marigold flower fermentation product is obtained by centrifugation. The marigold flower fermentation product is fermented and centrifuged in the multi-stage fermentation unit in sequence, and finally centrifuged to obtain the solid marigold flower final fermentation product;

[0012] Step 3) Separation:

[0013] The solid phase marigold flower final fermentation product is put into a supercritical extraction kettle to obtain a heavy phase fluid marigold yellow pigment crude product;

[0014] Step 4) Purification:

[0015] The crude marigold yellow pigment of the heavy phase fluid enters the distillation column to obtain lutein paste;

[0016] The lutein paste is injected into a low-temperature cooling tank, and n-hexane is added and stirred to dissolve. After dissolution, marigold crystals are added, and marigold yellow crystal pigment is obtained by filtration. The marigold yellow pigment is then obtained by crushing after low-temperature vacuum drying.

[0017] Furthermore: in the step 2), the temperature of the enzymatic fermentation in the fermentation tank is 40-50° C., the fermentation time is 12-24 hours, and the speed of the centrifugal separation is 4000-8000 r / min.

[0018] Furthermore: the amount of yeast and cellulase liquid in each fermentation tank is the same, and the weight ratio of the yeast and cellulase liquid to the weight of the marigold flowers is 0.1%-5%:1.

[0019] Furthermore: after the centrifugal separation, the liquid phase is an aqueous solution containing yeast and cellulase, and the liquid phase is returned to the fermentation tank of the solid fluidized bed for reuse.

[0020] Furthermore: in the step 3), the extraction pressure in the supercritical extraction kettle is 25-28 MPa, the temperature is 50-60° C., and the extraction time is 4-8 hours.

[0021] Further: in the step 4), the crude marigold yellow pigment of the heavy phase fluid enters the distillation column and is purified at the temperature of the four-stage heater to obtain lutein paste.

[0022] Furthermore: the temperature of the four-stage heater is: 40-45°C for the first stage, 40-45°C for the second stage, 30-35°C for the third stage, and 10-15°C for the fourth stage.

[0023] Furthermore: in the step 4), the temperature of the low temperature cooling tank is -15 to -20°C.

[0024] Further: in the step 3), carbon dioxide and petroleum ether are used as extraction solvents, and the flow rate of carbon dioxide is 2200-2600 kg / h;

[0025] The amount of petroleum ether added during the entire separation process of the supercritical extraction kettle is 100L.

[0026] Compared with the prior art, the present invention has at least one of the following beneficial effects:

[0027] (1) The present invention adopts a solid fluidized bed to break the cell wall of fresh marigold flowers, releases marigold yellow pigment from marigold flower cells, and uses a horizontal centrifuge to separate solid and liquid to obtain a final fermented product of marigold flowers with completely broken cell walls; the final fermented product of marigold flowers with completely broken cell walls is put into a supercritical extraction kettle, subjected to supercritical liquid extraction, and passed through a separation kettle to obtain a crude marigold yellow pigment product; the crude marigold yellow pigment product enters a distillation column for purification, and a refined marigold yellow pigment product that has been purified is obtained at the bottom of the distillation column, which is then injected into a low-temperature cooling tank, a small amount of marigold crystals are added as crystal nuclei, and then filtered to obtain marigold yellow pigment crystals, which are then crushed at low temperatures to obtain marigold yellow pigment.

[0028] (2) The method for extracting marigold yellow pigment of the present invention breaks the technical limitation of conventional marigold yellow pigment extraction. In particular, marigold yellow pigment is very easy to oxidize under high temperature. It does not require high-temperature drying and granulation, and does not use organic solvents. The produced marigold yellow pigment has a high content, is more environmentally friendly and healthier, and has broad application prospects.

[0029] (3) After the solid fluidized bed is broken, the liquid contains yeast and cellulase, which can be returned to the solid fluidized bed for continued use. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 Spectrum of lutein of the present invention.

[0031] Figure 2 It is a schematic diagram of the connection between the fermentation tank and the centrifuge in the fermentation unit of the present invention. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0033] Embodiment 1:

[0034] A method for extracting lutein from fresh marigold flowers comprises the following steps:

[0035] (1) Marigold flower crushing

[0036] Weigh 3200.5 kg of fresh marigold flowers after picking, and crush them through a 40-mesh sieve using a crusher.

[0037] (2) Solid fluidized bed wall breaking

[0038] The crushed material is transported to the solid fluidized bed for wall breaking through a pump. The solid fluidized bed is composed of multi-stage fermentation units connected together. Each stage of the fermentation unit includes a fermentation tank and a centrifuge. The multi-stage fermentation unit is arranged in five stages.

[0039] Each fermentation unit is equipped with a feed port for adding crushed materials, yeast and cellulase liquid, and 4 kg of yeast and cellulase liquid are added to each fermentation tank. The fermentation tank is enzymatically fermented at 45°C for 24 hours, and the fermented materials are centrifuged in a horizontal centrifuge at 4000 rpm.

[0040] The fermentation tank of the primary fermentation unit is centrifuged for fermentation, and the solid marigold flower fermentation product obtained after centrifugation is then sent to the secondary fermentation unit. The fermentation tank of the secondary fermentation unit is centrifuged for fermentation, and the solid marigold flower fermentation product obtained after centrifugation is then sent to the tertiary fermentation unit. The fermentation tank of the tertiary fermentation unit is centrifuged for fermentation, and the solid marigold flower fermentation product obtained after centrifugation is then sent to the quaternary fermentation unit. The fermentation tank of the quaternary fermentation unit is centrifuged for fermentation, and the solid marigold flower fermentation product obtained after centrifugation is then sent to the fifth fermentation unit. The fermentation tank of the fifth fermentation unit is centrifuged for fermentation, and the solid marigold flower final fermentation product is then obtained. Centrifugal separation releases marigold yellow pigment from marigold flower cells in the final marigold flower fermentation product.

[0041] The liquid phase obtained by each stage of centrifugation is a water solution containing yeast and cellulase, and the liquid phase can be returned to the solid fluidized bed reuse fermentation tank. The five-stage fermentation unit fermentation tank performs fermentation enzymolysis, making the fermentation enzymolysis more thorough.

[0042] (3) Extraction and separation: The solid phase marigold flower final fermentation product with complete wall breaking is put into a supercritical extraction kettle. The pressure of the extraction kettle is set to 28 MPa, the temperature of the extraction kettle heater is set to 45°C, carbon dioxide is used as the extraction solvent (with some petroleum ether as the extractant), the flow rate of carbon dioxide is 2200 kg / h, the amount of petroleum ether is 100 L, the extraction is performed for 5 hours, and the heavy phase fluid obtained after decompression to normal pressure separation is the crude marigold yellow pigment, and the light phase is the oily substance containing impurities.

[0043] (4) Purification:

[0044] Distillation column purification: The heavy phase enters the distillation column under pressure (1MP). Under the temperature control of the four-stage heater (first stage: 40℃; second stage 40℃; third stage 35℃; fourth stage 15℃), the heavy phase flows downward and is collected at the bottom of the first heater (lutein paste); the light phase flows upward with the carbon dioxide liquid, passes through the third and fourth heaters, and collects oil impurities at the top of the fourth heater. Finally, the net weight of the heavy phase lutein paste separated is 31.88kg; the net weight of the separated oil impurities is 5.18kg.

[0045] Refining and purification: inject marigold lutein paste into a low-temperature cooling tank, add 100L of n-hexane at the same time, stir to dissolve, then add 1% marigold crystals as crystal nuclei, control the temperature at -20°C, maintain for 24 hours, filter to obtain marigold yellow crystal pigment, and then crush it after low-temperature vacuum drying to obtain marigold yellow pigment.

[0046] Embodiment 2:

[0047] A method for extracting lutein from fresh marigold flowers comprises the following steps:

[0048] (1) Marigold flower crushing:

[0049] Weigh 3200.5 kg of fresh marigold flowers after picking, and crush them through a 40-mesh sieve using a crusher.

[0050] (2) Solid fluidized bed wall breaking:

[0051] The crushed material is transported to the solid fluidized bed for wall breaking through a pump. The solid fluidized bed is composed of multi-stage fermentation units connected together. Each stage of the fermentation unit includes a fermentation tank and a centrifuge. The multi-stage fermentation unit is arranged in five stages.

[0052] Each fermentation unit is equipped with a feed port for adding crushed materials, yeast and cellulase liquid, and 4 kg of yeast and cellulase liquid are added to each fermentation tank. The fermentation tank is enzymatically fermented at 40°C for 12 hours, and the fermented materials are centrifuged in a horizontal centrifuge at 8000 rpm.

[0053] The fermentation tank of the primary fermentation unit is centrifuged for fermentation, and the solid marigold flower fermentation product obtained after centrifugation is then sent to the secondary fermentation unit. The fermentation tank of the secondary fermentation unit is centrifuged for fermentation, and the solid marigold flower fermentation product obtained after centrifugation is then sent to the tertiary fermentation unit. The fermentation tank of the tertiary fermentation unit is centrifuged for fermentation, and the solid marigold flower fermentation product obtained after centrifugation is then sent to the quaternary fermentation unit. The fermentation tank of the quaternary fermentation unit is centrifuged for fermentation, and the solid marigold flower fermentation product obtained after centrifugation is then sent to the fifth fermentation unit. The fermentation tank of the fifth fermentation unit is centrifuged for fermentation, and the solid marigold flower final fermentation product is then obtained. Centrifugal separation releases marigold yellow pigment from marigold flower cells in the final marigold flower fermentation product.

[0054] The liquid phase obtained by each stage of centrifugation is a water solution containing yeast and cellulase, and the liquid phase can be returned to the solid fluidized bed reuse fermentation tank. The five-stage fermentation unit fermentation tank performs fermentation enzymolysis, making the fermentation enzymolysis more thorough.

[0055] (3) Extraction and separation:

[0056] The final fermentation product of solid-phase marigold flowers with completely broken walls was put into a supercritical extraction kettle. The pressure of the extraction kettle was set to 25 MPa, the temperature of the extraction kettle heater was set to 45°C, carbon dioxide was used as the extraction solvent (with some petroleum ether as the extractant), the flow rate of carbon dioxide was 2600 kg / h, the amount of petroleum ether was 100 L, the extraction was performed for 4 hours, and the heavy phase fluid obtained after decompression to normal pressure and separation was the crude marigold yellow pigment, and the light phase was the oily substance containing impurities.

[0057] (4) Purification

[0058] Distillation column purification: The heavy phase enters the distillation column at a pressure of 1MP. Under the temperature control of the four-stage heater (first stage: 45°C; second stage 45°C; third stage 30°C; fourth stage 10°C), the heavy phase flows downward and is collected at the bottom of the first heater (lutein paste); the light phase flows upward with the carbon dioxide liquid, passes through the third and fourth heaters, and the oil impurities are collected at the top of the fourth heater.

[0059] The net weight of the heavy phase lutein paste finally separated was 31.88kg; the net weight of the separated oil impurities was 5.18kg.

[0060] Refining and purification: inject marigold yellow pigment paste into a low-temperature cooling tank, add 100L of n-hexane at the same time, stir to dissolve, then add 1% marigold crystals as crystal nuclei, control the temperature at -20°C, maintain for 24 hours, filter to obtain marigold yellow crystal pigment, and then pulverize after low-temperature vacuum drying to obtain marigold yellow pigment.

[0061] Embodiment 3:

[0062] A method for extracting lutein from fresh marigold flowers comprises the following steps:

[0063] (1) Marigold flower crushing:

[0064] Weigh 3200.5 kg of fresh marigold flowers after picking, and crush them through a 40-mesh sieve using a crusher.

[0065] (2) Solid fluidized bed wall breaking:

[0066] The crushed material is transported to the solid fluidized bed for wall breaking through a pump. The solid fluidized bed is composed of multi-stage fermentation units connected together. Each stage of the fermentation unit includes a fermentation tank and a centrifuge. The multi-stage fermentation unit is arranged in five stages.

[0067] Each fermentation unit has a feed port in the fermentation tank, which is convenient for adding crushed materials, yeast and cellulase liquid, and 4 kg of yeast and cellulase liquid are added to each fermentation tank. The fermentation tank is enzymatically fermented at 50°C for 18 hours, and the fermented materials are centrifuged in a horizontal centrifuge at 6000 rpm.

[0068] The fermentation tank of the primary fermentation unit is centrifuged for fermentation, and the solid marigold flower fermentation product obtained after centrifugation is then sent to the secondary fermentation unit. The fermentation tank of the secondary fermentation unit is centrifuged for fermentation, and the solid marigold flower fermentation product obtained after centrifugation is then sent to the tertiary fermentation unit. The fermentation tank of the tertiary fermentation unit is centrifuged for fermentation, and the solid marigold flower fermentation product obtained after centrifugation is then sent to the quaternary fermentation unit. The fermentation tank of the quaternary fermentation unit is centrifuged for fermentation, and the solid marigold flower fermentation product obtained after centrifugation is then sent to the fifth fermentation unit. The fermentation tank of the fifth fermentation unit is centrifuged for fermentation, and the solid marigold flower final fermentation product is then obtained. Centrifugal separation releases marigold yellow pigment from marigold flower cells in the final marigold flower fermentation product.

[0069] The liquid phase obtained by each stage of centrifugation is a water solution containing yeast and cellulase, and the liquid phase can be returned to the solid fluidized bed reuse fermentation tank. The five-stage fermentation unit fermentation tank performs fermentation enzymolysis, making the fermentation enzymolysis more thorough.

[0070] (3) Extraction and separation:

[0071] The final fermentation product of solid-phase marigold flowers with completely broken walls was put into a supercritical extraction kettle. The pressure of the extraction kettle was set at 26 MPa, the temperature of the extraction kettle heater was set at 45°C, carbon dioxide was used as the extraction solvent (with some petroleum ether as the extractant), the flow rate of carbon dioxide was 2400 kg / h, the amount of petroleum ether was 100 L, the extraction was performed for 8 hours, and the heavy phase fluid obtained after decompression to normal pressure and separation was the crude marigold yellow pigment, and the light phase was the oily substance containing impurities.

[0072] (4) Purification

[0073] Distillation column purification: The heavy phase enters the distillation column under pressure (1MP). Under the temperature control of the four-stage heater (first stage: 42°C; second stage 403°C; third stage 32°C; fourth stage 13°C), the heavy phase flows downward and is collected at the bottom of the first heater (lutein paste); the light phase flows upward with the carbon dioxide liquid, passes through the third and fourth heaters, and the oil impurities are collected at the top of the fourth heater.

[0074] The net weight of the heavy phase lutein paste finally separated was 31.88kg; the net weight of the separated oil impurities was 5.18kg.

[0075] Refining and purification: inject marigold yellow pigment paste into a low-temperature cooling tank, add 100L of n-hexane at the same time, stir to dissolve, then add 1% marigold crystals as crystals and crystal nuclei, control the temperature at -18°C, maintain for 24 hours, filter to obtain marigold yellow crystal pigment, and then pulverize after low-temperature vacuum drying to obtain marigold yellow pigment.

[0076] The detection results of marigold yellow pigment obtained in Examples 1-3 are shown in Table 1 below.

[0077] Table 1 Refining and purification test results

[0078]

[0079] By the above method, a high-content lutein crystal product can be directly prepared from marigold flowers, with the total lutein content being greater than 80%. The method uses solid fluidized bed enzymatic technology to replace the traditional flower fermentation, drying and granulation technology, making the production process simpler, the production cost lower, and more suitable for large-scale promotion.

[0080] Although the present invention is described herein with reference to a number of illustrative embodiments of the present invention, it will be appreciated that those skilled in the art may devise many other modifications and implementations that fall within the scope and spirit of the principles disclosed herein. More specifically, within the scope of the present disclosure, drawings, and claims, a variety of variations and modifications may be made to the components and / or layout of the subject combination layout. In addition to the variations and modifications made to the components and / or layout, other uses will also be apparent to those skilled in the art.

Claims

1. A method for extracting lutein from fresh marigold flowers, characterized in that: The following steps are involved: Step 1) Crush the marigold flowers: After picking, fresh marigold flowers are crushed in a crusher; Step 2) Solid fluidized bed wall breaking: The solid fluidized bed is composed of multiple fermentation units connected together, and each fermentation unit includes a fermentation tank and a centrifuge; Yeast and cellulase liquid are added to the fermentation tank of each fermentation unit, the crushed marigold flowers are first fermented in the fermentation tank of the first fermentation unit and then centrifuged in a centrifuge, and the marigold flower fermentation product is obtained by centrifugation. The marigold flower fermentation product is fermented and centrifuged in the multi-stage fermentation unit in sequence, and finally centrifuged to obtain the solid marigold flower final fermentation product; Step 3) Separation: The solid phase marigold flower final fermentation product is put into a supercritical extraction kettle to obtain a heavy phase fluid marigold yellow pigment crude product; Step 4) Purification: The crude marigold yellow pigment of the heavy phase fluid enters the distillation column to obtain lutein paste; The lutein paste is injected into a low-temperature cooling tank, and n-hexane is added and stirred to dissolve. After dissolution, marigold crystals are added, and marigold yellow crystal pigment is obtained by filtration. The marigold yellow pigment is then obtained by crushing after low-temperature vacuum drying.

2. The method for extracting lutein from fresh marigold flowers according to claim 1, characterized in that: In the step 2), the temperature of the enzymatic fermentation in the fermentation tank is 40-50° C., the fermentation time is 12-24 hours, and the speed of the centrifugal separation is 4000-8000 r / min.

3. The method for extracting lutein from fresh marigold flowers according to claim 1, characterized in that: The amounts of yeast and cellulase liquid in each fermentation tank are the same, and the weight ratio of the yeast and cellulase liquid to the weight of the marigold flowers is 0.1%-5%:

1.

4. The method for extracting lutein from fresh marigold flowers according to claim 1, characterized in that: After the centrifugal separation, the liquid phase is an aqueous solution containing yeast and cellulase, and the liquid phase is returned to the fermentation tank of the solid fluidized bed for reuse.

5. The method for extracting lutein from fresh marigold flowers according to claim 1, characterized in that: In the step 3), the extraction pressure in the supercritical extraction kettle is 25-28 MPa, the temperature is 50-60° C., and the time is 4-8 hours.

6. The method for extracting lutein from fresh marigold flowers according to claim 1, characterized in that: In the step 4), the crude marigold yellow pigment of the heavy phase fluid enters the distillation column and is purified at the temperature of the four-stage heater to obtain lutein paste.

7. The method for extracting lutein from fresh marigold flowers according to claim 6, characterized in that: The temperature of the four-stage heater is: 40-45°C for the first stage, 40-45°C for the second stage, 30-35°C for the third stage, and 10-15°C for the fourth stage.

8. The method for extracting lutein from fresh marigold flowers according to claim 1, characterized in that: In the step 4), the temperature of the low temperature cooling tank is -15 to -20°C.

9. The method for extracting lutein from fresh marigold flowers according to claim 1, characterized in that: In the step 3), carbon dioxide and petroleum ether are used as extraction solvents, and the flow rate of carbon dioxide is 2200-2600 kg / h; The amount of petroleum ether added during the entire separation process of the supercritical extraction kettle is 100L.

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