DD148889A3 - METHOD FOR THE PRODUCTION OF EGYPTIAN YEAST - Google Patents

Abstract

Process for the production of protein-rich yeasts, characterized in that in the cultivation by known methods the cytokines or cytokinin-like substances, in particular kinetin, are added to the C- and N-containing culture medium.

Description

18 059 4 -ι-

The invention relates to a process for the production of protein-rich yeasts «

It is known that plant hormones, such as. As kinetin, growth and differentiation of plants influence. They seem to intervene in the regulation of genetic information. Their exact mechanism of action is unknown «

The effect of kinetin on microorganisms is known only as a growth-stimulating effect in bacteria. There are no indications of the influence on the protein synthesis of yeast cells.

In the microbial protein synthesis, z. As the feed yeast production, there is a demand to economize biomass production by increasing the yield or by increasing the cellular protein content.

The methods used hitherto to increase the protein content of feed or nutrient yeast production did not lead to the desired successes «

The purpose of the invention is to stimulate the protein synthesis of yeasts so as to increase the protein content of the cells.

The object of the invention is to achieve the desired increase by adding an agent that is toxicologically harmless to humans and animals to the culture medium.

It has now surprisingly been found that cytokinins, in particular kinetin, or substances with cytokininähnlichen effects, such as DNA-RNA hydrolyzates added in small concentrations to the fermentation medium, significantly increase the protein content of yeast cells. The fermentation conditions corresponded to the usual ones described for C- and N-containing media in aerobic fermentation.

Yeasts of the genera Saccharomyces, Pichia, Hansenula, Candida, Torulopsis, Rhodotorula are used.

The invention will be explained in more detail by the following examples.

example 1

For fermentation, the following substrate is used: 20 g of glucose; 1 », 2 g (NHI |) ₂ SO2 |; 0.7 ml H3PO2} (85%); °> ² 5 S MgSOi} · 7 H2O; with tap water ad 1 1. The potassium requirement of the proliferating cells is ensured by the separate feed of potassium hydroxide solution, which serves for the pH stabilization. Kinetin is added in amounts between 10 "to 10 μg / l of nutrient solution.

The nutrient solution is fed to a continuous fermentation apparatus in which it is optimally aerated. The residence time is H to 5 hours, the pH is at. ¹ 1.5 ·. The temperature is maintained at 28 to 30 ⁰ C. For fermentation VJuchshefe (Candida utilis) is used. The effluent from the fermentation apparatus is separated. The resulting yeast is dried (feed yeast). The filtrate is recycled to prepare the subsequent substrate.

3 1

The following values were obtained:

Kinetin (g / l)

crude ' pure protein {% of HTS) (% of HTS) 50.5 34.0 54.3 41.5 55.6 39.8 56.6 40.1 57.7 42.1

10-4 ΙΟ " ⁶ 10-8

Example 2

The procedure is as in Example 1. However, the yeast produced after separation is used directly for isolation of protein (for human consumption).

Example 3

Cells from Sacch. cerevisiae are grown at 30 ^° C. continuously, sterile, under aerobic conditions at pH 1, 5 and a residence time of 5-8 hours. The medium contains 30 g of glucose; 6.4 g (NH ₂ SO ₄ ) 0.7 ml H 3 PO 4 (85 mg), 0.5 g MgSO 4, 7 H ₂ O, 1 g CaCl 2, 1 g NaCl, 0.5 mg thiamine hydrochloride, 0.2 mg riboflavin, 0.2 mg pyridoxine hydrochloride, 0.3 mg pantothenol, 2 mg nicotinamide, 2 mg inositol, 2 ^ g biotin and trace elements (A - Z solution) per liter distilled water.

5 × 10 -3 / 10 ~ 10 g of kinetin / 1 solution are added to the culture medium - pH consistency is ensured by automatic dosing of KOH.

With 10 "3 g kinetine addition, a 22 % increase in crude and pure protein value was measured.

Claims (3)

Invention claims: 1. A process for producing protein-rich yeasts, characterized that in the cultivation by known methods to the C and N-containing culture medium cytokinins or cytokininähnliche substances, in particular kinetin, are added. 2. Method according to item 1, characterized that yeasts of the genera Saccharomyces, Pichia, Hansenula, Candida, Torulopsis or Rhodotorula be used. 3. The method according to item 1 and 2, characterized in that kinetin is used in concentrations of 10 ~ 2 \ ^ ± _s io ~ l °. i \ . Method according to item 1, characterized in that, for example, DNA-RNA hydrolyzates can be used as cytokinin and as substances having a cytokinin-like action.