DE3734764A1 - Process for the preparation of 1,3-propanediol - Google Patents

Abstract

In the fermentation of glycerol, known methods yield 1,3-propanediol in yields of up to about 60%. According to the invention, the yield of 1,3-propanediol can be further increased by fermentation with the aid of the bacterial strain Klebsiella pneumoniae DSM 4270 in the presence of cobalt(II) salts. Preparation of 1,3-propanediol.g

Description

The invention relates to a process for the preparation of propanediol (1,3) from renewable resources using microorganisms men.

Short-chain diols have industrial and technical importance as a construction stones for polymers, solvents and pharmaceuticals. They are stock parts of adhesives, ointments, abrasives, lubricating oils, frost protective agent and brake fluids. Propanediol (1,3) has some men genüber significant applications. These include the manufacture of polyesters and polyurethanes and the synthesis of special he terocyclic compounds.

For the preparation of propanediol (1,3) can malonic acid diethyl hy be drilled.

There are also microbiological processes for the production of propane diol- (1,3) known. Thus, according to Mickelson and Werkmann, J. Bact. 39, 709 (1940) glycerol by various Citrobacter strains to propane diol (1,3) fermented. The yield is 30 to 60%. The same authors describe in Enzymologia 8, 252 (1940) Fer mentation of glycerine to propanediol (1,3) by means of Aerobacter Strains. The conversion of glycerol to propanediol (1,3) is included about 45%, which also produces butanediol (2,3) as by-product.

After Forage and Foster, J. Bact. 149, 413 (1982), glycerin can be fermented by Klebsiella pneumoniae ATCC 8724 and 25,955 under anaerobic or aerobic conditions in neutral or weakly alkaline medium to give propanediol (1,3). Acrolein is also formed in significant quantities. The growth of microorganisms can be stimulated by vitamin B ₁₂ here.

According to Forsberg, Applied and Environmental Microbiology 53, 639 (1987) can be with the help of Chlostridium strains with the addition of cobalt chloride and cobalamin convert glycerol to propanediol (1,3), wherein Turnover can be achieved up to a maximum of 61%.  

In the known processes for the preparation of propanediol (1,3) who Sales and yields reached about 60%. In the process, too By-products, especially acrolein, formed to a greater extent, the make it difficult to clean the desired product.

The object of the present invention is an improved process for the preparation of propanediol (1,3). In particular it should be increased while yield and turnover.

The object is achieved in that glycerol by the microorganism Klebsiella pneumoniae DSM 4270 in the presence of fermentable carbohydrates and cobalt (II) salts under aerobic Conditions fermented.

Suitable carbohydrates are pentoses and hexoses such as Arabinose, xylose, glucose or mannose. Preferably, glucose becomes used.

The aqueous culture broth into which the bacterial strain Klebsiella pneu moniae DSM 4270 initially contains 5 to 15% glycerol and 2 to 10% carbohydrates. The nutrient medium contains 0.01 to 100 μM cobalt (II) salts, for example cobalt (II) chloride. The Ge It is preferably 0.05 to 10 μM.

The nutrient medium may additionally contain a complex organic nutrient source le like yeast extract, soy peptone or corn steep liquor. It can but also purely synthetic nutrient solutions are fermented, the contain only inorganic salts except the substrates mentioned.

The fermentation of glycerol is aerobic, preferably with vermin ventilation, executed.

The temperature is maintained in a range of 25 to 35 ° C. before Preferably, a temperature of 30 to 33 ° C is set. During the reaction, the pH is kept at 4 to 7. virtue wise, a pH of 4.5 to 6 is set.  

In the reaction is generally by-produced butanediol (2,3) formed. The by-product formation is strong by the fermenta tion conditions and depends mainly on the pH and of the temperature off.

Under the conditions according to the invention, 100 g of glycerol 60 are used to 82 g of propanediol (1,3) formed, giving a maximum possible Aus from 73 to 100%.

In carrying out the method, a nutrient solution is first set, which contains glycerol as a carbon source. Then cobalt becomes (II) salt, whereupon the solution with a preculture of adhesive siella pneumoniae DSM 4270 is inoculated. Hexoses or pentoses can used together with glycerin. But you can also do it first Add after the beginning of the fermentation.

For large batches, the fermentation broth is under aerobic condition stirred. In small batches, the fermentation is under Shaking the reaction flask performed. The reaction is in the air common after 48 to 72 hours.

When the reaction is complete, the cells are removed from the batch separates and the propanediol (1,3) by distillation and fractionated Isolated distillation in pure form.

The propanediol (1,3) prepared by the process according to the invention is characterized by its NMR spectrum and by its gas chromatographic Behavior identified.

example

In a 5 l fermenter, 4 l of culture broth are added, which per liter

6.64 g K₂HPO₄ 1.5 g KH₂PO₄ 3 g (NH₄) ₂SO₄ 50 g glycerin 0.3 g MgSO₄ · 7 H₂O 0.1 g NaCl 0.058 g CaCl₂ · 2 H₂O 0.022 g FeSO₄ · 7 H₂O 0.003 g MnSO₄ · H₂O 0.075 g ZnSO₄ · 7H₂O 5 g yeast extract 2.5 μmol CoCl₂

contains. This culture broth is sterilized and then with 40 ml Vor culture of the strain Klebsiella pneumoniae DSM 4270 inoculated, whereupon the Fermentation takes place under the following conditions:

pH 5.5
Temperature 30 ° C
Stirrer speed 300 rpm
Ventilation with 0.15 vvm air

After a fermentation time of 7 hours, 50 g Glu per liter cose added to the fermentation broth. After 72 hours, the Fer mentation ended.

After separation of the cells, the analysis shows that mined per 100 g Glycerol 63 g of propanediol (1,3) have been formed.

If no glucose is added, per 100 g of degraded glycerol le 38 g of propanediol (1,3) were synthesized.

Claims (7)

1. A process for the preparation of propanediol (1,3) in high yields from glycerol using microorganisms, characterized in that glycerol using Klebsiella pneumoniae DSM 4270 in the presence of at least one pentose or hexose and cobalt (II) -salts fermented under aerobic conditions. 2. The method according to claim 1, characterized, that is fermented in the presence of glucose. 3. The method according to claim 1, characterized, that in the presence of 0.01 to 100 uM cobalt (II) salts fermen advantage. 4. The method according to claim 3, characterized, that in the presence of 0.05 to 10 uM cobalt (II) chloride fermen advantage. 5. The method according to claim 1, characterized, that the fermentation at 25 to 35 ° C in the pH range of 4 to 7 performs. 6. The method according to claim 5, characterized, that the fermentation is carried out at 30 to 33 ° C. 7. The method according to claim 5, characterized, that the fermentation is carried out in the pH range of 4.5 to 6.