Method for extracting lipid of rubber particles from fresh latex of rubber tree

Abstract

The invention relates to a method for extracting lipid of rubber particles from fresh latex of rubber trees, and belongs to the technical field of rubber processing. The method comprises five steps of pretreatment, extraction, separation, concentration and re-concentration. According to the method, the extraction efficiency of the lipid is improved through the methods of pretreatment, extraction, separation, concentration and the like, the quality of the lipid is improved, and efficient preparation and utilization of lipid resources in the low-fat plant raw materials containing high moisture are achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of rubber processing, and particularly relates to a method for extracting lipids of rubber particles from fresh latex of rubber trees. Background Art

[0002] The latex collected from rubber trees is the only commercial source of natural rubber. Cis-1,4-polyisoprene polymer is a strategic raw material and is widely used in various industries. Fresh latex of rubber trees is a white opaque liquid, containing about 60% water, 35% cis-1,4-polyisoprene polymer chains, and 5% non-isoprene molecules (proteins, lipids, carbohydrates, and minerals). The latex of rubber trees is a colloidal dispersion, which contains a variety of micron-sized objects, mainly rubber particles (RP), rubber-like substances, and Frey-Wyssling complexes dispersed in the cytoplasm.

[0003] Currently, the research on lipids in the latex of Hevea brasiliensis mainly focuses on qualitative and quantitative analysis of lipids using liquid chromatography-mass spectrometry technology. There is no report on the extraction process of lipids of rubber particles in fresh latex. Most lipid extraction processes rely on organic solvent extraction and evaporation concentration. This technology is applicable to raw materials with high lipid content. However, fresh latex of rubber trees has the characteristics of high water content, easy coagulation, and low lipid content. It is difficult to extract lipids from fresh latex and lipids of rubber particles using traditional processes.

[0004] Therefore, how to overcome the deficiencies of the existing technology is an urgent problem to be solved in the current technical field of rubber processing. Summary of the Invention

[0005] The purpose of the present invention is to solve the deficiencies of the existing technology and provide a method for extracting lipids of rubber particles from fresh latex of rubber trees.

[0006] To achieve the above purpose, the technical scheme adopted by the present invention is as follows: A method for extracting lipids of rubber particles from fresh latex of rubber trees, comprising the following steps: The first step, pretreatment: performing low-temperature centrifugation on fresh latex of rubber trees, and taking the uppermost rubber particle layer; the low temperature is 0°C to 8°C; The second step, extraction: extracting the rubber particle layer obtained in the first step with an organic solvent to obtain an extraction solution; wherein, during extraction, the extraction temperature is 20°C to 50°C; The third step, separation: adding a salt solution to the extraction solution obtained in the second step, and standing at room temperature for 0.5 h to 2 h to separate the aqueous phase and the organic phase; taking the organic phase solution, which is the lipid extraction solution; the salt solution is sodium chloride or potassium chloride solution, with a concentration of 8 to 10 g / L and a pH of 6.0 to 8.5; Step 4, Concentration: Concentrate the lipid extract obtained in Step 3 to obtain a crude extract of lipids; the concentration temperature is 30°C to 55°C; Step 5, Re - concentration: Moisten the crude extract obtained in Step 4 with an organic solvent, and the mass ratio of the crude extract to the organic solvent is 1:2 to 1:5, then evaporate and concentrate again to obtain the lipid of refined rubber particles, and store it at -20°C; among them, the concentration temperature is 40°C to 75°C.

[0007] Furthermore, preferably, in the first step, the centrifugation speed is 10000 rpm to 13000 rpm, and the centrifugation time is 1 h to 1.5 h.

[0008] Furthermore, preferably, in the second step, the organic solvent is at least one of chloroform, methanol, ethanol with a volume concentration of 75% to 100%, petroleum ether, ethyl acetate, and diethyl ether; during extraction, the mass ratio of the rubber particle layer to the extraction solution is 1:3 to 1:15, and the extraction time is 2 hours to 12 hours; Furthermore, preferably, in the third step, during separation, the volume ratio of the extraction solution to the salt solution is 1:1 to 10:1; separate with a separating funnel.

[0009] Furthermore, preferably, in the fourth step, during concentration, evaporation concentration or vacuum concentration is adopted, and the concentration time is 30 minutes to 60 minutes.

[0010] Furthermore, preferably, in the fifth step, the organic solvent is at least one of petroleum ether, ethyl acetate, chloroform, and methanol; during concentration, the concentration time is 20 minutes to 40 minutes.

[0011] The present invention also provides the lipid of rubber particles extracted by the above - mentioned method for extracting the lipid of rubber particles from fresh latex of rubber trees.

[0012] In the fifth step of the present invention, during re - concentration, concentrate until the solvent residue is lower than 0.1% by mass fraction.

[0013] The present invention provides a method for extracting lipids with a simple process in plant components with extremely low lipid content, realizing the efficient preparation and utilization of lipid resources in low - fat plants with high moisture.

[0014] Compared with the prior art, the beneficial effects of the present invention are: The present invention uses fresh latex of rubber tree as raw material, and obtains rubber particle layer through centrifugation method at low temperature and high speed. Organic solvent extraction can fully extract lipids, and salt solution makes the separation of aqueous phase and organic phase simple, greatly improving the extraction efficiency of lipids. The concentration method shortens the extraction time of lipids, and secondary concentration purifies the crude lipid extract, with simple operation and low requirements for equipment. The lipid content of rubber particles obtained by the present invention can reach 10 g / L, and the extraction rate is about 60% by mass.

[0015] The present invention improves the extraction efficiency of lipids in rubber particles through methods such as pretreatment, extraction, separation and concentration, improves the quality of lipids, realizes the efficient preparation and utilization of lipid resources in low-fat plant raw materials containing high moisture, and lays a foundation for subsequent experimental research on lipids in rubber particles. Specific embodiments

[0016] The following further describes the present invention in detail with reference to embodiments.

[0017] Those skilled in the art will understand that the following embodiments are only used to illustrate the present invention and should not be construed as limiting the scope of the present invention. For those not specified in the embodiments regarding specific techniques or conditions, they shall be carried out according to the techniques or conditions described in the literature in this field or according to the product specifications. For those materials or equipment whose manufacturers are not specified, they are all conventional products that can be obtained by purchase. Example 1

[0018] A method for extracting lipids from rubber particles in fresh latex of rubber tree, comprising the following steps: First step, pretreatment: perform low-temperature centrifugation on fresh latex of rubber tree, and take the uppermost rubber particle layer; the low temperature is 4°C; Second step, extraction: extract the rubber particle layer obtained in the first step with an organic solvent to obtain an extraction solution; wherein, during extraction, the extraction temperature is 30°C; Third step, separation: add a salt solution to the extraction solution obtained in the second step, and let it stand at room temperature for 1 h to separate the aqueous phase and the organic phase; take the organic phase solution, which is the lipid extraction solution; the salt solution is sodium chloride solution, with a concentration of 9 g / L and a pH of 7; Fourth step, concentration: concentrate the lipid extraction solution obtained in the third step to obtain a crude lipid extract; the concentration temperature is 40°C; Fifth step, re-concentration: soak the crude extract obtained in the fourth step with an organic solvent, and the mass ratio of the crude extract to the organic solvent is 1:4, then evaporate and concentrate again to obtain refined lipids of rubber particles, and store them at -20°C; wherein, the concentration temperature is 50°C. Example 2

[0019] A method for extracting lipids from rubber particles in fresh latex of rubber trees, comprising the following steps: First step, pretreatment: subject the fresh latex of rubber trees to low-temperature centrifugation, and take the uppermost rubber particle layer; the low temperature is 0 °C; Second step, extraction: extract the rubber particle layer obtained in the first step with an organic solvent to obtain an extraction solution; wherein, during extraction, the extraction temperature is 20 °C; Third step, separation: add a salt solution to the extraction solution obtained in the second step, and let it stand at room temperature for 0.5 h to separate the aqueous phase and the organic phase; take the organic phase solution, which is the lipid extraction solution; the salt solution is a sodium chloride solution with a concentration of 8 g / L and a pH of 6.0; Fourth step, concentration: concentrate the lipid extraction solution obtained in the third step to obtain a crude extract of lipids; the concentration temperature is 30 °C; Fifth step, re-concentration: soak the crude extract obtained in the fourth step with an organic solvent, and the mass ratio of the crude extract to the organic solvent is 1:2, and then evaporate and concentrate again to obtain refined lipids of rubber particles, and store them at -20 °C; wherein, the concentration temperature is 40 °C.

[0020] In the first step, the centrifugation speed is 10000 rpm and the centrifugation time is 1 h.

[0021] In the second step, the organic solvent is chloroform; during extraction, the mass ratio of the rubber particle layer to the extraction solution is 1:3, and the extraction time is 2 hours; In the third step, during separation, the volume ratio of the extraction solution to the salt solution is 1:1; separate with a separatory funnel.

[0022] In the fourth step, during concentration, evaporation concentration is adopted, and the concentration time is 30 minutes.

[0023] In the fifth step, the organic solvent is petroleum ether; during concentration, the concentration time is 20 minutes. Example 3

[0024] A method for extracting lipids from rubber particles in fresh latex of rubber trees, comprising the following steps: First step, pretreatment: subject the fresh latex of rubber trees to low-temperature centrifugation, and take the uppermost rubber particle layer; the low temperature is 8 °C; Second step, extraction: extract the rubber particle layer obtained in the first step with an organic solvent to obtain an extraction solution; wherein, during extraction, the extraction temperature is 50 °C; Third step, separation: add a salt solution to the extraction solution obtained in the second step, and let it stand at room temperature for 2 h to separate the aqueous phase and the organic phase; take the organic phase solution, which is the lipid extraction solution; the salt solution is a potassium chloride solution with a concentration of 10 g / L and a pH of 8.5; Step 4, Concentration: Concentrate the lipid extract obtained in Step 3 to obtain a crude extract of lipids; the concentration temperature is 55°C; Step 5, Re - concentration: Moisten the crude extract obtained in Step 4 with an organic solvent, the mass ratio of the crude extract to the organic solvent is 1:5, and then evaporate and concentrate again to obtain the refined lipid of rubber particles, and store it at -20°C; among them, the concentration temperature is 75°C.

[0025] In the first step, the centrifugation speed is 13000 rpm and the centrifugation time is 1.5 h.

[0026] In the second step, the organic solvent is a mixed solvent of ethanol and methanol (volume ratio 1:1); during extraction, the mass ratio of the rubber particle layer to the extraction solution is 1:15, and the extraction time is 12 hours; In the third step, during separation, the volume ratio of the extraction solution to the salt solution is 10:1; separate with a separating funnel.

[0027] In the fourth step, during concentration, vacuum concentration is adopted, and the concentration time is 60 minutes.

[0028] In the fifth step, the organic solvent is ethyl acetate; during concentration, the concentration time is 40 minutes. Example 4

[0029] A method for extracting the lipid of rubber particles from fresh latex of rubber trees, comprising the following steps: First step, Pretreatment: Perform low - temperature centrifugation on fresh latex of rubber trees, and take the uppermost rubber particle layer; the low temperature is 4°C; Second step, Extraction: Extract the rubber particle layer obtained in the first step with an organic solvent to obtain an extraction solution; among them, during extraction, the extraction temperature is 30°C; Third step, Separation: Add a salt solution to the extraction solution obtained in the second step, and let it stand at room temperature for 1 h to separate the aqueous phase and the organic phase; take the organic phase solution, which is the lipid extract; the salt solution is a potassium chloride solution with a concentration of 10 g / L and a pH of 8.5; Fourth step, Concentration: Concentrate the lipid extract obtained in the third step to obtain a crude extract of lipids; the concentration temperature is 55°C; Fifth step, Re - concentration: Moisten the crude extract obtained in the fourth step with an organic solvent, the mass ratio of the crude extract to the organic solvent is 1:5, and then evaporate and concentrate again to obtain the refined lipid of rubber particles, and store it at -20°C; among them, the concentration temperature is 75°C.

[0030] In the first step, the centrifugation speed is 13000 rpm and the centrifugation time is 1.5 h.

[0031] In the second step, the organic solvent is a mixed solvent of ethanol, ether, petroleum ether, and ethyl acetate with a volume concentration of 90% (volume ratio 1:1:1:1); during extraction, the mass ratio of the rubber particle layer to the extraction solution is 1:10, and the extraction time is 10 hours; In the third step, during separation, the volume ratio of the extraction solution to the salt solution is 6:1; separation is carried out using a separating funnel.

[0032] In the fourth step, during concentration, evaporation concentration is used, and the concentration time is 40 minutes.

[0033] In the fifth step, the organic solvent is a mixed solvent of chloroform and methanol (volume ratio 1:1); during concentration, the concentration time is 30 minutes. Example 5

[0034] A method for extracting lipids of rubber particles from fresh latex of rubber trees, comprising the following steps: First step, pretreatment: subject the fresh latex of rubber trees to low-temperature centrifugation, and take the uppermost rubber particle layer; the low temperature is 4°C; Second step, extraction: extract the rubber particle layer obtained in the first step with an organic solvent to obtain an extraction solution; during extraction, the extraction temperature is 40°C; Third step, separation: add a salt solution to the extraction solution obtained in the second step, and let it stand at room temperature for 1 h to separate the aqueous phase and the organic phase; take the organic phase solution, which is the lipid extraction solution; the salt solution is a potassium chloride solution with a concentration of 9 g / L and a pH of 7; Fourth step, concentration: concentrate the lipid extraction solution obtained in the third step to obtain a crude extract of lipids; the concentration temperature is 40°C; Fifth step, re-concentration: soak the crude extract obtained in the fourth step with an organic solvent, the mass ratio of the crude extract to the organic solvent is 1:3, and then evaporate and concentrate again to obtain refined lipids of rubber particles, and store them at -20°C; among them, the concentration temperature is 55°C.

[0035] In the first step, the centrifugation speed is 12000 rpm, and the centrifugation time is 1.2 h.

[0036] In the second step, the organic solvent is ethanol with a volume concentration of 75%; during extraction, the mass ratio of the rubber particle layer to the extraction solution is 1:8, and the extraction time is 10 hours; In the third step, during separation, the volume ratio of the extraction solution to the salt solution is 8:1; separation is carried out using a separating funnel.

[0037] In the fourth step, during concentration, evaporation concentration is used, and the concentration time is 45 minutes.

[0038] In the fifth step, the organic solvent is ethyl acetate; during concentration, the concentration time is 30 minutes.

[0039] Application Example 1 A method for extracting lipids from rubber particles in fresh latex of rubber trees, comprising the following steps: First step, pretreatment: Collect 50 mL of fresh latex in an ice bath, perform low-temperature centrifugation on the fresh latex of rubber trees, and take the uppermost rubber particle layer; the low temperature is 4 °C; Second step, extraction: Extract the rubber particle layer obtained in the first step with an organic solvent to obtain an extraction solution; wherein, during extraction, the extraction temperature is room temperature; Third step, separation: Add a salt solution to the extraction solution obtained in the second step to separate the aqueous phase and the organic phase, and let it stand at room temperature for 2 hours to form layers; Take the organic phase solution, which is the lipid extraction solution; the pH of the salt solution is 7.0; The salt solution uses a 9 g / L potassium chloride solution; Fourth step, concentration: Concentrate the lipid extraction solution obtained in the third step to obtain a crude extract of lipids; the concentration temperature is 55 °C; Fifth step, re-concentration: Moisten the crude extract obtained in the fourth step with an organic solvent, the mass ratio of the crude extract to the organic solvent is 1:5, and then evaporate and concentrate again to obtain 0.5 g of refined lipids of rubber particles, and store it at -20 °C; wherein, the concentration temperature is 50 °C.

[0040] In the first step, the centrifugation speed is 13000 rpm and the centrifugation time is 1 h.

[0041] In the second step, the organic solvent is a mixed solvent of chloroform and methanol (volume ratio 2:1); during extraction, the mass ratio of the rubber particle layer to the extraction solution is 1:5, and the extraction time is 8 hours; In the third step, during separation, the volume ratio of the extraction solution to the salt solution is 2:1; separate with a separating funnel.

[0042] In the fourth step, during concentration, evaporation concentration is used, and the concentration time is 40 minutes.

[0043] In the fifth step, the organic solvent is petroleum ether; during concentration, the concentration time is 20 minutes.

[0044] Comparative Example 1 A method for extracting lipids from rubber particles in fresh latex of rubber trees, comprising the following steps: First step, pretreatment: Collect 50 mL of fresh latex in an ice bath, perform low-temperature centrifugation on the fresh latex of rubber trees, and take the uppermost rubber particle layer; the low temperature is 8 °C; Second step, extraction: Extract the rubber particle layer obtained in the first step with an organic solvent to obtain an extraction solution; wherein, during extraction, the extraction temperature is 50 °C; Step 3, Separation: Add a salt solution to the leaching solution obtained in Step 2 to separate the aqueous phase and the organic phase, and let it stand at room temperature for 20 minutes to form layers; Take the organic phase solution, which is the lipid extraction solution; The pH of the salt solution is 7.0; The salt solution is a 9 g / L sodium chloride solution; Step 4, Concentration: Concentrate the lipid extraction solution obtained in Step 3 to obtain 0.1 g of the crude lipid extract, and store it at -20 °C; The concentration temperature is 55 °C; In Step 1, the centrifugation speed is 10,000 rpm and the centrifugation time is 1.5 h.

[0045] In Step 2, the organic solvent is a mixed solvent of chloroform and methanol (volume ratio 2:1); During leaching, the mass ratio of the rubber particle layer to the leaching solution is 1:10, and the leaching time is 10 hours; In Step 3, during separation, the volume ratio of the leaching solution to the salt solution is 3:1; Separate with a separating funnel.

[0046] In Step 4, during concentration, evaporation concentration is used, and the concentration time is 50 minutes.

[0047] The importance of the fifth step of re-concentration is illustrated by the comparison of the above two examples, that is, the amount of the obtained product varies greatly. If re-concentration is not carried out, the extraction rate of lipids will be greatly reduced.

[0048] The present invention also provides the following comparative experiments: Comparative Example 1 The difference between Comparative Example 1 and Example 5 is that only the experiments of Step 1 + Step 2 + Step 4 of Example 5 are carried out, and the remaining steps are not carried out; It is found that no lipids are extracted, and there are no lipids after evaporation concentration.

[0049] Comparative Example 2 The difference between Comparative Example 2 and Example 5 is that the first step is treated at room temperature, and the rest are the same; It is found that during the experiment, the latex is easy to coagulate and it is difficult to extract lipids.

[0050] Comparative Example 4 The difference between Comparative Example 3 and Example 5 is that the fourth step is at a concentration temperature of 70 °C, and the rest are the same; It is found that when the temperature is too high, during evaporation concentration, the extract will jump out of the container, and by-products are also generated, and the amount of the finally obtained product is greatly reduced.

[0051] In summary, the method of the present invention can effectively extract the lipids of rubber particles, improve the quality of lipids, realize the efficient preparation and utilization of lipid resources in low-fat plant raw materials containing high moisture, and lay a foundation for subsequent experimental research on the lipids of rubber particles. For example, the extracted lipids can be used to simulate the lipid-protein monolayer membrane structure of rubber particles in rubber trees. In the field of natural rubber processing technology, the extracted lipids can be used to develop natural surfactants and study antioxidants for rubber products, etc.

[0052] The foregoing has shown and described the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments, and what is described in the above embodiments and the specification is only to illustrate the principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention will also have various changes and improvements, and these changes and improvements fall within the scope of the present invention claimed. The scope of the present invention claimed is defined by the appended claims and their equivalents.

Claims

1. A method for extracting the lipid of rubber particles from fresh latex of rubber trees, characterized in that, It includes the following steps: The first step, pretreatment: subject the fresh latex of rubber tree to low-temperature centrifugation, and take the uppermost rubber particle layer; the low temperature is 0°C to 8°C; The second step, extraction: extract the rubber particle layer obtained in the first step with an organic solvent to obtain an extraction solution; wherein, during extraction, the extraction temperature is 20°C to 50°C; The third step, separation: add a salt solution to the extraction solution obtained in the second step, and let it stand at room temperature for 0.5 h to 2 h to separate the aqueous phase and the organic phase; take the organic phase solution, which is the lipid extraction solution; the salt solution is sodium chloride or potassium chloride solution, with a concentration of 8 to 10 g / L and a pH of 6.0 to 8.5; The fourth step, concentration: concentrate the lipid extraction solution obtained in the third step to obtain a crude extract of lipids; the concentration temperature is 30°C to 55°C; The fifth step, re-concentration: soak the crude extract obtained in the fourth step with an organic solvent, and the mass ratio of the crude extract to the organic solvent is 1:2 to 1:5, then evaporate and concentrate again to obtain the lipid of refined rubber particles, and store it at -20°C; wherein, the concentration temperature is 40°C to 75°C.

2. The method for extracting lipids of rubber particles from fresh latex of rubber trees according to claim 1, wherein In the first step, the centrifugation speed is 10,000 rpm to 13,000 rpm, and the centrifugation time is 1 h to 1.5 h.

3. The method for extracting lipids of rubber particles from fresh latex of rubber trees according to claim 1, wherein In the second step, the organic solvent is at least one of chloroform, methanol, ethanol with a volume concentration of 75% to 100%, petroleum ether, ethyl acetate, and ether; during extraction, the mass ratio of the rubber particle layer to the extraction solution is 1:3 to 1:15, and the extraction time is 2 hours to 12 hours.

4. The method for extracting lipids of rubber particles from fresh latex of rubber trees according to claim 1, characterized in that, In the third step, during separation, the volume ratio of the extraction solution to the salt solution is 1:1 to 10:1; separate with a separating funnel.

5. The method for extracting the lipid of rubber particles from fresh latex of rubber trees according to claim 1, characterized in that, In the fourth step, during concentration, evaporation concentration or vacuum concentration is adopted, and the concentration time is 30 minutes to 60 minutes.

6. The method for extracting the lipid of rubber particles from fresh latex of rubber trees according to claim 1, characterized in that, In the fifth step, the organic solvent is at least one of petroleum ether, ethyl acetate, chloroform, and methanol; during concentration, the concentration time is 20 minutes to 40 minutes.

7. The lipid of rubber particles extracted by the method for extracting the lipid of rubber particles from the fresh latex of rubber tree according to any one of claims 1 to 6.