DEVELOPING AN EFFICIENT TECHNOLOGY FOR RELEASING PROLINE FROM CULTURE LIQUID

Abstract

The process of the electrodialysis method for desalting L-proline permeate in a five-chamber electrodialyzer is studied. In the mode of ultimate current density, changes in the content of DM, pH, the electrical conductivity of solutions in the dilute and concentrating chambers, and the circuit voltage in the process of permeate desalting depending on the time are determined.

The investigations have shown that the electrodialysis enables to purify permeate from mineral ions (98.2% degres of desalting), as well as from concomitant basic and acidic amino acids with minimal losses of the target product. It was found that in the desalted permeate of proline, the concentration of mineral ions is not more than 0.06 g / L.

The specific consumption of electric energy in the process of permeate desalting was 0,425 A/h/kg, and current output-59,1%.

An approximate calculation shows that electrodialysis method of permeate desalting is 3 times cheaper than the ion exchange method of desalting.

The process of separating L-proline from the accompanying initial amino acids of the desalted permeate was studied based on the ability of the accompanying initial aminoacids to form Schiff bases with 5-sulfosalicylic aldehyde on the porous anion exchanger APA-8p. It is revealed that, in the process of proline separation from the accompanying amino acids, as well as during their elution, 5-sulfosalicylic aldehyde is not washed out from the resin that allows to use the anion exchanger repeatedly without additional regeneration.

The optimal parameters of the process (the values of fhe maximum current density at desalting and purifying, the forms of the resin and pH of the desalted solution), as well as the yield of proline from the culture liquid and its purity have been determined.