DE1543719C - Process for the microwave production of 1 threonine - Google Patents

Description

The invention relates to a process for the production of L-threonine from L-aspartic acid by Fermentation using microorganisms.

L-threonine, 2-amino-3-hydroxybutyric acid, is an essential known amino acid. she is a essential acid as it maintains the growth of rats (Schmidt, Amino Acids, p. 1265 [1944]). L-threonine is found in whole eggs, skimmed milk, casein, gelatin, and other proteins present. It is used medicinally as a nutrient, and its recommended dose is at normal adults about 1.0 g per day (Rose, Fed. Proc, Vol. 8, p. 546 [1949]).

The invention relates to a method for the microwave production of L-threonine, thereby characterized in that Azotobacter indicus ATCC 9037, Arthrobacter ureafaciens ATCC 7562, Bacillus circulansATCC 9966, Brevibacterium helvolum ATCC 11 822, 'Micrococcus sodonensis ATCC 19 212 or Candida utilis ATCC 16 321 in an aqueous Nutrient medium containing L-aspartic acid as a starting material, cultivated and known per se Way, the L-threonine formed wins from the fermentation liquid obtained.

The L-aspartic acid used as a starting material according to the invention is in a suitable one Contain culture medium made from both a synthetic and a natural medium can exist. The medium also contains the usual essential nutrients for the growth of the applied tribal. These nutrients are known in the art and include substances as carbon sources, nitrogen sources, inorganic compounds and the like in suitable amounts. As a carbon source are z. B. Carbohydrates, such as glucose, fructose, maltose, cane sugar, starch, starch hydrolysates, molasses and the like, or any other suitable carbon sources, such as e.g. B. glycerine, mannitol, sorbitol, organic acids, Glutamic acid and the like. These substances can be used individually or in mixtures. Various types of inorganic or organic salts or compounds can be used as the nitrogen source into consideration, such as B. urea or ammonium salts, such as ammonium chloride, ammonium sulfate, Ammonium nitrate, ammonium phosphate and the like, or one or more amino acids or natural nitrogenous ones Substances such as corn steep liquor, yeast extract, meat extract, peptone, fish meal, casein hydrolysates, Casamino acids, soluble fish scraps, rice shell extract and the like. These substances can also be used can be used individually or as a mixture. Inorganic Compounds Adding to the Culture Medium may be added include magnesium sulfate, sodium phosphate, potassium dihydrogen phosphate, Potassium monohydrogen phosphate, iron sulfate or other iron salts, manganese chloride, calcium chloride, etc., However, when the cultivation is carried out with the same microorganisms in a culture medium which only contains the above nutrients, but without the addition of! .- aspartic acid contains as the main starting material in the context of a comparative experiment, the amount formed is L-threonine so little or negligible compared to the case where L-aspartic acid is used. The amount of aspartic acid employed is generally between about 1 and 5 percent by weight.

The cultivation is carried out at a temperature between approximately 25 and 40 ^° C., the pH value being set to neutral, approximately 7.0, at the beginning of the cultivation. Cultivation for 2 to 7 days is sufficient to produce favorable amounts of L-threonine. The aerobic microorganisms are cultivated under .aerobic conditions, for example aerobic shaking of the culture or stirring of a submerged culture with the introduction of air. Anaerobic microorganisms are cultivated using a surface culture. The culture medium is preferably kept at a neutral pH value during the cultivation.

After the fermentation has ended, the L-threonine formed is removed from the fermentation liquid by conventional means Process obtained, e.g. B. by adsorption on an ion exchange resin and subsequent elution, Constriction and precipitation or countercurrent distribution after conversion to the N-benzoyl derivative.

The following example serves as a further explanation of the invention without limiting it. Unless otherwise stated, the percentages are based on weight.

example

Different types of bacteria, actinomycetes and yeasts as given in the table, were inoculated from an agar section into large test tubes, each containing 10 ml of the following Culture medium contained:

1%! .- aspartic acid (previously with
Ammonia neutralized)

1% glucose

0.05% K ₂ HPO ₄

0.025% MgSO ₄ · _{7H 2} O
0.2% (NH ₄ ) ₂ SO ₄

0.3% yeast extract

0.3% CaCOj

Cultivation was then carried out with aerobic shaking carried out at 30 ° C. for 4 days. The amounts of! .- threonine formed are in the table specified. .

Amount; m

educated

Microorganisms used ₍ . ·] H _rcon j "

'. ' Us / ml)

Azotobacter indicus KY 3201

ATCC 9037 0.3

Arlhrobacter ureafaciens KY 3152

ATCC 7562 0.3

Bacillus circulars KY 3325 ATCC 9966 0.3

Brevibacterium helvolum KY 3455

ATCCII 822 0.3

Micrococcus sodonensis KY 3466

ATCC 19 212 0.3

(andida utilis KY 5027 ATCC 16 321 0.3

Candida ulilis ATCC 16 321 was approved by the Institute for l-crmunticruiig. (Osaka, Japan) | IR) number 0396 I received, and Micrococcus soilonensis ΛΤ ('(' (κ, 19 212 is a natural isolate, which as M.soilonensis according to the animal description of S. A a ro η so η {Journal of Bacteriology, Vol. 69 , Pp. 67 to 69 | 1955 |) idcnlili / icrl.

Claims (1)

Claim: Π 822, Micrococcus sodonensis ATCC 19 212 Process for the microbial production of Candida utilis ATCC 16 321 in an aqueous L-threonine, characterized in that nutrient medium containing L-aspartic acid as an that one contains Azotobacter indicus ATCC 9037, arthritis material, cultivated and in itself bacter ureafaciens ATCC 7562, Bacillus circulans 5 in a known manner from the L-threonine formed ATCC 9966, Brevibacterium helvolum ATCC. the obtained fermentation liquid wins.