阅读说明：本技术 一种采用稀酸水解从杜仲中提取杜仲胶的方法 (Method for extracting gutta-percha from eucommia ulmoides by dilute acid hydrolysis ) 是由 陈新德 张海荣 袁鸽 陈雪芳 熊莲 于 2020-07-13 设计创作，主要内容包括：本发明公开了一种采用稀酸水解从杜仲中提取杜仲胶的方法。该方法包括以下步骤：将杜仲用乙醇进行抽提,获得含绿原酸的乙醇溶液和抽提渣；然后往抽提渣中加入一定量的稀酸溶液,在100～180℃下水解反应0.5～6h,产物经固液分离后得到含糖水解液和水解渣；将水解渣加至非极性有机溶剂中,在50～80℃下回流6～24h,趁热过滤,滤液冷却、沉淀即得到杜仲胶。相较于传统的杜仲胶提取工艺,本发明采用稀酸水解从杜仲中提取杜仲胶,通过控制酸水解的程度,极大提高了杜仲胶的收率。利用该方法可获得杜仲胶外,还可同时收获绿原酸和含糖水解液,具有综合利用率高,操作简便、经济效益好等特点。(The invention discloses a method for extracting gutta-percha from eucommia ulmoides by dilute acid hydrolysis. The method comprises the following steps: extracting eucommia ulmoides with ethanol to obtain ethanol solution containing chlorogenic acid and extraction residue; adding a certain amount of dilute acid solution into the extraction residue, carrying out hydrolysis reaction for 0.5-6 h at 100-180 ℃, and carrying out solid-liquid separation on the product to obtain a sugar-containing hydrolysate and hydrolysis residue; and adding the hydrolysis residues into a nonpolar organic solvent, refluxing for 6-24 h at 50-80 ℃, filtering while hot, cooling the filtrate, and precipitating to obtain the gutta-percha. Compared with the traditional gutta-percha extraction process, the invention adopts dilute acid hydrolysis to extract the gutta-percha from the eucommia, and greatly improves the yield of the gutta-percha by controlling the degree of the acid hydrolysis. Besides the gutta-percha, the method can also simultaneously harvest chlorogenic acid and sugar-containing hydrolysate, and has the characteristics of high comprehensive utilization rate, simple and convenient operation, good economic benefit and the like.)

1. A method for extracting gutta-percha from eucommia ulmoides by dilute acid hydrolysis is characterized by comprising the following steps: extracting eucommia ulmoides with ethanol to obtain ethanol solution containing chlorogenic acid and extraction residue; adding a certain amount of dilute acid solution into the extraction residue, carrying out hydrolysis reaction for 0.5-6 h at 100-180 ℃, and carrying out solid-liquid separation on the product to obtain a sugar-containing hydrolysate and hydrolysis residue; and adding the hydrolysis residues into a nonpolar organic solvent, refluxing for 6-24 h at 50-80 ℃, filtering while hot, cooling the filtrate, and precipitating to obtain the gutta-percha.

2. The method for extracting gutta-percha from eucommia ulmoides oliv by dilute acid hydrolysis according to claim 1, wherein the mass ratio of the ethanol to the eucommia ulmoides oliv is 2-10: 1.

3. The method for extracting gutta percha from eucommia ulmoides oliv by dilute acid hydrolysis according to claim 1, wherein the mass fraction of the dilute acid solution is 0.01-10%; the acid is at least one of sulfuric acid, hydrochloric acid and nitric acid.

4. The method for extracting gutta-percha from eucommia ulmoides oliv by dilute acid hydrolysis according to claim 1 or 3, wherein the mass fraction of eucommia ulmoides oliv extract residue in the hydrolysis reaction is 5-40%.

5. The method of claim 1, wherein the non-polar organic solvent is at least one selected from the group consisting of petroleum ether, cyclohexane, dichloromethane, and toluene; the mass ratio of the nonpolar organic solvent to the hydrolysis residues is 5-10: 1.

6. The method of claim 1, wherein the eucommia ulmoides is selected from at least one of eucommia ulmoides leaves, eucommia ulmoides bark, and eucommia ulmoides fruit.

Technical Field

The invention belongs to the technical field of high-valued utilization of eucommia ulmoides, and particularly relates to a method for extracting gutta-percha from eucommia ulmoides by adopting dilute acid hydrolysis.

Background

China is a country with large rubber consumption, and rubber resources mainly depend on import. The research and production of eucommia bark, a special industry capable of replacing natural rubber, are of great practical significance due to the requirement of national security strategy. Eucommia ulmoides is a single-genus plant of the family Eucommiaceae, and is a unique and precious economic tree species in China. The leaves, bark, fruits and seeds of eucommia ulmoides Oliver contain different amounts of gutta percha. The gutta-percha is a natural polymer material, belongs to an isomer with natural rubber, and has a molecular structure of trans-1, 4-polyisoprene (TPI). Gutta-percha is widely used as a raw material for elastomer materials, shape memory materials, antenna sealing materials, medical materials, high-temperature damping materials, and the like.

The gutta-percha content in the gutta-percha cells of the eucommia ulmoides tree is low, and the viscosity is high, so that the gutta-percha cannot be directly collected by tapping like natural rubber, and the extraction process of the gutta-percha is special. Generally, the extraction of gutta-percha is divided into 3 steps: breaking cell walls, extracting gutta-percha, and separating and purifying the gutta-percha. The common extraction methods mainly comprise: mechanization, alkaline leaching, fermentation (microbiological method), solvent method or a combination of the methods. As a kind of lignocellulose, eucommia ulmoides contains a large amount of cellulose, hemicellulose and lignin in addition to gutta percha. Most of these substances are lost as waste materials during the gutta percha improving process, causing a great waste of resources. Therefore, the invention provides a new eucommia ulmoides gum extraction method, and has important practical significance for realizing the utilization of the whole components of eucommia ulmoides.

Disclosure of Invention

The invention aims to provide a method for extracting gutta-percha from eucommia ulmoides by adopting dilute acid hydrolysis. Besides the gutta-percha, the method can also simultaneously harvest chlorogenic acid and sugar-containing hydrolysate, and has the characteristics of high comprehensive utilization rate, simple and convenient operation, good economic benefit and the like.

In order to achieve the purpose, the invention adopts the following technical scheme:

a method for extracting gutta-percha from eucommia ulmoides by dilute acid hydrolysis comprises the following steps: extracting eucommia ulmoides with ethanol to obtain ethanol solution containing chlorogenic acid and extraction residue; adding a certain amount of dilute acid solution into the extraction residue, carrying out hydrolysis reaction for 0.5-6 h at 100-180 ℃, and carrying out solid-liquid separation on the product to obtain a sugar-containing hydrolysate and hydrolysis residue; and adding the hydrolysis residues into a nonpolar organic solvent, refluxing for 6-24 h at 50-80 ℃, filtering while hot, cooling the filtrate, and precipitating to obtain the gutta-percha.

Preferably, the mass ratio of the ethanol to the eucommia ulmoides is 2-10: 1.

Preferably, the mass fraction of the dilute acid solution is 0.01-10%; the acid is at least one of sulfuric acid, hydrochloric acid and nitric acid.

Preferably, in the hydrolysis reaction, the mass fraction of the eucommia ulmoides extraction residue is 5-40%.

Preferably, the nonpolar organic solvent is at least one selected from petroleum ether, cyclohexane, dichloromethane and toluene; the mass ratio of the nonpolar organic solvent to the hydrolysis residues is 5-10: 1.

Preferably, the eucommia ulmoides is at least one selected from eucommia ulmoides leaves, eucommia ulmoides bark and eucommia ulmoides fruits.

The invention has the technical effects that:

1) while extracting gutta-percha, cellulose and hemicellulose in eucommia can be converted into sugar-containing hydrolysate, and the sugar-containing hydrolysate can be used for producing chemicals such as bioethanol and biobutanol by fermentation.

2) While extracting the gutta-percha, the chlorogenic acid can be obtained, and the economic benefit of the extraction process is further improved.

3) Compared with the traditional gutta-percha extraction process, the invention adopts dilute acid hydrolysis to extract the gutta-percha from the eucommia, and greatly improves the yield of the gutta-percha by controlling the degree of the acid hydrolysis.

Detailed Description

In order to make the above objects of the present invention more comprehensible, embodiments of the present invention are described in detail below with reference to specific examples, but the scope of the present invention is not limited to the following examples.