CS267134B1 - Process for processing yeast biomass into cell concentrate for ergosterol isolation - Google Patents

Abstract

The solution falls into the field of biotechnology with the use of the first product - ergosterol in the pharmaceutical industry and the second product - yeast autolysate - yeast extract in the food industry. The subject of the solution is a method of obtaining another product from yeast biomass - yeast extract in addition to the ergosterol produced so far by the action of ethyl alcohol or ethyl acetate, which induce cell osmolysis and accelerate the enzymatic decomposition of cell proteins and other macromolecules. The advantage of the procedure is that the cell extract is obtained without prior mechanical crushing of cells and, unlike cell autolysis, ergosterol remains firmly bound to cell structures. The yeast cell suspension is first incubated for 2 to 6 hours in a mixture with ethyl alcohol or ethyl acetate at a temperature of about 50 °C, then the liquid portion is separated from the extracted cells by centrifugation or filtration, the organic agent is first distilled off from the liquid portion and the cell extract is concentrated by evaporation or dried. In the remaining solid portion under these conditions, all ergosterol remains bound to the cell structures. Ergosterol is then isolated by the usual procedure.

Description

The invention relates to the processing of yeast biomass into a cell concentrate for the isolation of ergosterol for pharmaceutical purposes and at the same time into a yeast extract for use in the food industry as a flavoring and nutritional supplement for food products.

In the Czechoslovak Socialist Republic, an anti-curvature vitamin - calciferol from ergosterol, which was mainly imported from Japan or the GDR until 1987 and was only produced to a limited extent from domestic baker's yeast, has been produced for pharmaceutical purposes for about 40 years, mainly for export to non-socialist countries. The production process for the isolation of ergosterol abroad is not known to us, because it is a production secret and is not published. In the Czechoslovak Socialist Republic, ergosterol has been produced since the beginning of 1988 exclusively from domestic baker's yeast in an annual volume of 4 and 5 tons by first hydrolyzing the yeast cell suspension by boiling with sodium or potassium hydroxide to saponify the lipid content of cell dry matter. The unsaponifiable matter, which contains the released ergosterol, is extracted with non-polar solvents and further purified to crystalline ergosterol. The rest of the yeast biomass dry matter, which consists mainly of denatured proteins and cell wall polysaccharides and represents about 98 99% by weight of the yeast biomass dry matter, is discharged as unusable waste to the wastewater treatment plant. are a commercially useful substance that is used as a flavoring and nutritional supplement in the production of dried soups, sauces and a wide range of other food products. The need for dried yeast extract for this purpose is almost exclusively covered by imports from non-socialist countries ·

The essence of the invention is that in the processing of yeast biomass into ergosterol concentrate, the protein components of the biomass are simultaneously used to produce yeast extract without the need to first mechanically crush the yeast cells, using the effect of cell plasmolysis.

A suspension of yeast cells with a dry matter content of 10% by weight is incubated for 2 to 8 hours at 35-55 ° C in a mixture with substances which alter the osmotic pressure of the external environment of the cells and thus cause plasmolysis of the cells, such as is, for example, ethyl acetate or ethyl alcohol. The higher the reaction temperature or the higher the concentration of plaxmolyzing agent, the shorter the reaction time. By treating the yeast cell suspension with ethyl acetate or ethyl alcohol at 3 to 8 liters of plaamolyzing agent per 100 liters of yeast suspension, the plasma membrane is separated from the cell wall and the cell volume is substantially reduced as a result of the reduction in intracellular water content. The inner cellular contents are wrinkled, disorganizing and destroying the inner cellular structures, and the desolubilizing activity of the intracellular enzymes begins. Along with the outgoing intracellular water, smaller molecules diffuse through the cell wall into the external environment, resulting from the enzymatic degradation of protein molecules, nuclease proteins, lipoproteins, B group vitamin molecules, mineral salt ions and water-soluble grafts of other enzymatically transformed substances. N _e přesáhne-li incubation period optimální hodnotu 3 <5 hours at 50 ° C, zůstává ergosterol pevně vázán to membrane structures platmolyzovaných buněk, kdežto více než half of all nitrogen compounds and more than one 1/3 sušiny yeast biomasy the enzymatic conversion to VE vodě soluble grafts that prediffuse the cell wall into the external environment of cells. By prolonging the incubation time beyond the optimal value, the cell membrane structures are enzymatically disrupted and ergosterol is released into the external environment - an extract that becomes cloudy and acquires fine sensory properties. , suitable as a raw material for processing into ergosterol.

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The sulfur filtrate, which contains enzymatic grafts of cell macromolecules, can be concentrated or dried to a yeast extract of pleasant meat odor and taste for use in the food industry after distilling off the flame hydrolyzing agent.

The advantage of the invention is the possibility to obtain another valuable product - yeast extract from biomass in addition to ergosterol, without the need for mechanical crushing of yeast cells.

Example 1

A suspension of Saccharoinyces cerevisiae cells with a dry matter content of 15% by weight and a nitrogen content of crude protein of 57.6 g of protein per 100 g of dry matter was divided into 100 ml conical flasks, preheated in a water bath to 50 ° C and mixed with 6 ml, 7 ml or 8 ml of absolute ethyl alcohol. The individual flasks were then placed in a water bath and kept at 50 ° C. 4.5 and 6 hours after mixing the cell suspension and ethyl alcohol, the cell fraction of the collected suspension samples was separated by centrifugation and the amount of dry matter of the extract after drying to constant weight was determined by the weighing method and the nitrogen content in the extract was determined by the Kjehldal method.

Table

concentration lodin incubation g of extract from g of crude protein ethyl alcohol at 50 ° C 100 g dry matter of 100 g of dry matter biomass biomass 4 23.5 33.3 6% vol. 5 32.7 46.6 6 39.8 53.3 4 37.6 49.7 7% vol. 5 41.3 58.2 6 42.1 .......... 59.4 4 36.7 55.5 8% vol. 5 41.2 57.5 6 40.7 56.0

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The maximum yield of yeast extract was obtained under incubation in cell conditions with a suspension of 7% by volume of absolute ethyl alcohol at a temperature of 50 ° C and an exposure time of 5 ° C for 6 hours.

Example 2

100 liters of yeast milk baker's yeast Saccharomyces cerevisiae D? (COY 21-4-85) containing 15% by weight, dry matter of biomass, containing 1.25% by weight, ergosterol in dry matter and 42.4% by weight, crude protein in dry matter, was mixed with 4 liters of ethyl acetate in a vessel of stainless steel, equipped with a low-speed stirrer and a heating water jacket. The mixture was heated to 50 ° C and incubated for 3 hours with gentle agitation. The solid (plasmolyzed cells) was then separated from the supernatant (yeast extract) by centrifugation on a flow centrifuge. The extract obtained was freed of most of the ethyl acetate by heating at 80 DEG C. for 5 minutes, mixed with 2.8 kg of sodium chloride, dried in a spray oven at an inlet temperature of 250 DEG C. and an outlet temperature of 85 DEG C. 9.35 kg of a dried, yellowish-white powder product, well soluble in water, with a pleasant meat aroma and taste, were obtained. The nitrogen content, calculated on the crude protein, was 361 g per 1 kg of powdered product. Cellular residues after polymerization with ethyl acetate contained 2.11% by weight of ergosterol in dry matter.

Claims (1)

Process for the processing of yeast biomass into a cell concentrate for the isolation of ergosterol and to a yeast extract for use in the food industry by the action of ethyl alcohol or ethyl acetate, characterized in that the aqueous suspension of Saccharomyces cerevisiae cells is incubated at 45-55 ° C for either 4-6 hours in mixtures with 6 to 8% by volume of ethyl alcohol or for 3 to 4 hours in a mixture with 3.5% by volume of ethyl acetate and then the solid cell fraction is separated for. isolating ergosterol from a clear cell extract that is concentrated or dried.