Investigation of L-DOPA and dopamine production in different fermantative conditions by using Citrobacter freundii (NRRL B-2643) microorganism

In this study, production of L-DOPA and Dopamine chemicals which are very important for treatment of Parkinson's disease and showing neurotransmitter feature were carried out by fermentation using of Citrobacter freundii (NRRL B-2643) microorganism. To maximize the production of these substances, the optimum properties of the fermentation medium which are mostly consist of natural components were determined. The experiments were performed using 250 ml shake-flasks and 1.0 L batch operated bioreactor. As a result of experiments which are performed, the maximum production amount of L-DOPA and Dopamine of 458 mg L-1 and 592 mg L-1 respectively, in the optimum fermentation medium which are containing 10 g L-1 yeast extract, 12.5 g L-1 peptone, 2.5 g L-1 sucrose, 1 g L-1 NaCl, 0.1 g L-1 casein, 0.75 g L-1 soy protein, 1 g L-1 ammonium sulfate, 1 g L-1 calcium chloride, % 5 v v-1 whey, % 2.5 v v-1 microorganism culture and fermentation conditions which is operated at 33 oC temperature, initial pH of 6.5 and adjusted to shaking speed of 200 rpm, were reached. In experiments which are performed in batch operated bioreactor, it was observed that the volumetric mass transfer coefficient (kLa) and oxygen consumption rate (ro) increased in parallel with increase of air inlet velocity. Key Words: L-DOPA, Dopamine, Citrobacter freundii (NRRL B-2643), Parkinson Disease, Fermentation, Batch Fermentation, Bioreactor parameters, Biotechnology.