RU2283655C1 - Method for production of biologically active substances - Google Patents

Abstract

FIELD: production of biologically active substances from birch bark, which represents waste from birch wood reprocessing.

SUBSTANCE: claimed method includes providing of water soluble substance concentrate namely betulinol concentrate and triterpenoid concentrate by birch bark treatment with polar extractant in birch bark:solvent ratio of 1:3-20; at temperature of 18-100°C. Water soluble substance concentrate is separated by filtration in form of extract, and birch bark is additionally extracted with organic solvent in ratio of 1:1-20, respectively. Betulinol concentrate is isolated from obtained extract by crystallization, and triterpenoid concentrate is obtained from mother liquor after extractant removing.

EFFECT: method for production of water soluble and fat soluble substance consentrates.

6 ck, 4 ex, 1 tbl

Description

The invention relates to methods for the isolation of biologically active substances from wood, namely to the rational use of birch bark - waste wood processing enterprises, and can be used to obtain medicinal, veterinary, cosmetic preparations, as well as in the food industry and agriculture.

A known method of separation of betulinol from birch bark, including the activation of birch bark at a temperature of 180-260 ° C and a pressure of 2-5 MPa simultaneously with alkaline hydrolysis and subsequent extraction with ethanol [1].

The disadvantage of this method is the difficulty in execution — high temperature, overpressure, and alkali regeneration are necessary, and only one biologically active product is obtained - betulinol concentrate.

A known method of producing betulinol from birch bark, including the extraction of birch bark with a mixture of petroleum ether 70-100 ° and toluene [2].

The disadvantage of this method is to obtain only one concentrate of biologically active substances betulinol, as well as the use for the extraction of a toxic aromatic solvent - toluene.

A known method of producing a concentrate of water-soluble substances from birch bark, including the extraction of bark with 40% ethanol with a ratio of raw materials: extractant 1: 1 for 8-30 hours [3].

The disadvantage of this method is to obtain only one concentrate of biologically active substances - a concentrate of water-soluble substances, as well as incomplete extraction of water-soluble substances due to the use of a small amount of extractant during extraction.

The closest to the achieved result is a method for the isolation of betulinol by the extraction of birch bark with hexane, which provides for the production of betulinol and triterpenoid concentrate simultaneously [4].

The disadvantage of this method is to obtain from birch bark only concentrates of fat-soluble biologically active substances.

The objective of the invention is to obtain the maximum possible number of biologically active substances contained in birch bark, the simplest and most environmentally friendly way.

The problem is solved by the proposed method, including the extraction of crushed birch bark with a polar extractant at M = 1: 3 ÷ 20, temperature 18-100 ° C, for 0.5-20 hours. Then the extract is separated from the birch bark, a concentrate of water-soluble substances in a solution is obtained, which can be concentrated or transferred to a dry state by removing the extractant in a known manner. Birch bark is re-extracted with a polar organic solvent. The extract is separated, concentrated and betulinol crystals are isolated from the concentrated extract, with a content of the main component of at least 90%. Then the solvent is completely distilled off from the mother liquor and a triterpenoid concentrate is obtained, the main components of which are betulinol and lupeol.

Of the polar extractants, inexpensive and low toxicity solvents are used. Of inorganic solvents, water or weak aqueous solutions of salts or acids are used, preferably physiological saline containing 3% sodium chloride, and of organic solvents, preferably ketone, the main representative of which is acetone, and aliphatic alcohols, mainly ethanol or isopropanol and mixtures thereof with water .

The possibility of obtaining concentrates of biologically active substances from birch bark is illustrated by examples.

Example 1. 50 g of crushed birch bark is loaded into a round bottom flask, pour 1000 ml of water and extracted, under reflux, for 0.5 hour at a temperature of 100 ° C. Then the extract is separated from birch bark by filtration and a concentrate of water-soluble substances in solution is obtained.

750 ml of acetone are refilled with birch bark and extracted at the boiling point of acetone for 3 hours. Then the extract is separated from the birch bark and 300 ml of acetone are distilled from it. Betulinol crystals precipitate from the concentrated extract, which are isolated from the solution in a known manner, and betulinol concentrate is obtained. Acetone is completely distilled off from the mother liquor and a triterpenoid concentrate is obtained.

Example 2. 50 g of crushed bark are poured into 250 ml of 100% isopropanol and extracted for 6 hours at a temperature of 25 ° C. Then the extract is separated from the birch bark and the solvent is distilled off from the extract. A dry concentrate of water-soluble substances is obtained.

Birch bark is refilled with 500 ml of 88% isopropanol and extracted at the boiling point of isopropanol for 1 hour. Then the extract is separated from the birch bark, 50 ml of isopropanol are distilled off from it. Betulinol crystals precipitate from the concentrated extract, which are isolated from the solution in a known manner, and betulinol concentrate is obtained.

The triterpenoid concentrate is obtained as in example 1.

Example 3. 50 g of crushed bark are poured into 150 ml of 30% ethanol and extracted for 20 hours at a temperature of 18 ° C. Then the extract is separated from birch bark and a concentrate of water-soluble substances is obtained.

Birch bark is refilled with 1000 ml of 30% ethanol and extracted at the boiling point of ethanol for 0.5 hours. Then the extract is separated from the birch bark and 500 ml of ethanol are distilled from it. Betulinol crystals precipitate from the concentrated extract, which are isolated from the solution in a known manner, and betulinol concentrate is obtained.

The triterpenoid concentrate is obtained as in example 1.

Example 4. 50 g of crushed birch bark is poured into 800 ml of physiological saline (0.9% aqueous solution of sodium chloride) and extracted for 2 hours at a temperature of 90 ° C. Then the extract is separated from birch bark and a concentrate of water-soluble substances is obtained.

Concentrates of betulinol and triterpenoids receive, as in example 2.

The output of concentrates of biologically active substances isolated from birch bark is presented in table 1.

Table 1.
The output of concentrates of biologically active substances isolated from birch bark Example No. The yield of concentrates,% of the initial birch bark Concentrate of water-soluble substances (dry in) Betulinol Concentrate Triterpenoid Concentrate one 0.4 11.8 14.2 2 0.6 12.0 12.8 3 0.7 10,4 12.6 four 0.5 12,2 13.8

The purity of betulinol concentrate in the main component is not lower than 90%.

INFORMATION SOURCES

1. RU 2131882.

2. RU 2184120.

3. RU 2045957.

4. RU 2206572.

Claims (6)

1. A method of obtaining a concentrate of biologically active substances from crushed birch bark, including its extraction and separation of the extract, characterized in that the extraction is carried out by a polar extractant at a ratio of 1: 3 ÷ 20, respectively, at a temperature of 18-100 ° C for 0.5-20 hours , then the obtained extract containing a concentrate of water-soluble substances is separated by filtration, and birch bark is additionally extracted with a polar organic solvent with a bark solvent ratio of 1: 10–20, respectively, from the obtained crystal extract Betulinol concentrate is isolated by lysis, and triterpenoid concentrate is obtained from the mother liquor after removal of the extractant. 2. The method according to claim 1, characterized in that the polar extractant is used in a mixture with water. 3. The method according to claim 1, characterized in that an inorganic extractant is used as a polar extract in the first extraction stage. 4. The method according to claim 3, characterized in that water is used as an inorganic extractant. 5. The method according to any one of claims 1 to 4, characterized in that acetone is used as the polar organic extractant. 6. The method according to any one of claims 1 to 4, characterized in that an aliphatic alcohol, for example ethanol or isopropanol, is used as an organic solvent.