CS214432B1 - A method of preparing cellobioses - Google Patents

Abstract

The invention relates to a method of preparing cellobiose from sweetened beet cuttings by enzymatic hydrolysis. The essence of the invention consists in the fact that beet cuttings, after releasing L-arabinose, pectin, lignin, are hydrolyzed enzymatically under the catalysis of a cellulolytic enzyme complex from the fungus Trichoderma viričLe for 6 to 24 hours at 40 to 60 °C, while D-glucose is removed from the reaction mixture by fermentation with brewer's yeast and cellobiose is deionized on ion separators crystallizes from ethyl alcohol.

Description

The invention relates to a process for the preparation of cellulose from sweetened beet pulp by enzymatic hydrolysis.

As part of his study of the complex use of beet pulp ea, he has solved the process of preparing cellobiose, which is highly sought after on the domestic and foreign markets, making use of the ideal substrate for enzymatic hydrolysis using the raw enzyme Trichoderma viride.

Several processes for the preparation of cellobiose chemically or synthetically by acetolysis of cellulose are described in the literature, where the cellobioctaacetate octaacetate is produced as an intermediate and is subjected to deacetylaemia. K, Hees, H, Priese; Annalen, 456, 49 (1927), P. Klein;

Z. Agnew. Chem. 25, 1409 (1922); A.P.N. Prauchimont; Ber. 12, 1941, (1897), discussed the reaction conditions for preparing cellobiose octaacetate, examining various ratios of sulfuric acid anhydride to cellulose, reaction temperature, and reaction time. Z. H. Skraup; Ber. 32, 2413, (1899), G. Zemplen; Ber. 59, 1258, (1926), C. C. Spencer; Cellulosechemistry, 10, 6, (1929), followed the isolation of the resulting intermediate, its deaeetylation using vigorous metal methoxides, and the crystallization of cellobiose from the reaction mixture using vigorous solvents. Helferich, B., Bredereck; Ber. 64, 2411, (1931), prepared in small amounts by cellobioacetate octaacetate by synthesis of 2,3,4,6, tetra-o-acetyl-α-D-glucopyranosyl bromide with methyl 2,3,6-tri-o-acetyl- (3-) D-glucopyranoside. E. Gilbert, F. Smith,

M. Stacey; J. Chem. Soc. 622, (1946) synthesized 2,3,4,6-tetra-o-acetyl-α-D-glucopyranosyl bromide and the sodium salt of 1,2,3,6-tetra-o-acetyl- β-D-glucopyranose 30% cellulose octaacetate.

Preparation of cellobiose by acetolysis from cellulose as well as by synthesis of 2,3,4,6 tetra-o-acetyl-o-D-glucopyranosyl bromide with methyl 2,3,6-tri-o-ethyl-β-D-glucopyranoside, respectively. the sodium salt of 1,2,3,6 tetra-o-acetyl-β-D-glucopyranose is difficult because it is prepared via the intermediate cell octaacetate octaacetate óo requiring a multi-step synthesis.

The proposed method of preparation of cellobiose with the enzyme Trichoderma viride is substantially simpler compared to the above methods of preparation.

SUMMARY OF THE INVENTION The invention is based on the fact that after the release of L-arabinose, pectin and lignin, the beet pulp is hydrolyzed enzymatically under catalysis by a cellulytic enzyme complex from the fungus Trichoderma viride for 6 to 24 hours at 40 to 60 ° C. Glucose as a by-product, which is removed by fermentation by brewer's yeast, cellobiose is crystallized from ethyl alcohol after deionization on ion exchangers.

The advantage of the proposed process for the preparation of cellobiose is that it allows the use of non-traditional waste raw material of beet pulp resulting from the production of sugar;

v provides a method of preparation that replaces multi-step synthesis;

provides a method that replaces a chemical preparation process by a biochemical procedure.

Example

A 2% substrate suspension in enzyme solution was prepared and 0.02%% added.

sodium azide and the culture medium ea were adjusted to pH 4.5. The incubation was carried out with stirring

214,432 hours at 50 ° C. Centrifuge at 5000 rpm. for 10 minutes, the supernatant was removed from the substrate and the supernatant was inactivated at 0.12 MPa for 20 minutes. D-glucose was removed from the inactivated solution by the addition of brewer's yeast (3% suspension) by incubation for 24 hours at room temperature. Centrifuge at 5000 rpm. for 10 minutes, the solution was separated from the yeast and poured through ion exchange resins Wofatit KPS 100-200 mesh in H ⁺ form and aaex SBW 100-200 mesh in OH form. The solution was decolorized with charcoal and concentrated to a syrup. Crystallization was performed from ethanol at a ratio of 1 s 3. The yield of cellobiose at mp 230-238 ° C, Z ° -7 ° C + 35 ° C (5% HgO) was 41%.

The invention has extensive application in the study of biochemical processes of living matter and in practical life, e.g. in cosmetics, medicine and food industry.

Claims (1)

The process for preparing cellobiose is characterized in that the beet pulp after L-arabinose, pectin and lignin release is hydrolyzed enzymatically under catalysis with a crude cellulytic enzyme from the fungus Trichoderma viride for 40 to 60 ° C for 6 to 4 hours to release cellobiose and D- D-glucose is removed by fermentation by brewer's yeast and, after deionization on ion exchangers, crystallization from ethanol yields chromatographically pure cellobiose.