สภาวะที่เหมาะสมต่อการผลิตเพนนิซิลิน จี โดย เพนนิซิเลียม ไคลโซจีนัม เอ 88 / วนิดา เรืองศรี = Optimal conditions for the production of penicillin G by penicillium chrysogenum A 88 / Vanida Ruangsri
The optimal conditions for the production of penicillin G by P.chrysogenum A 88 in shaken flask were determined. Medium containing 30 g/l lactose, 10 g/l glucose, 1.5 g/l total nitrogen of defatted soybean meal hydrolysate and 5g/l ammonium sulfate was found to be the best for the production whereas the optimal temperature for cultivation was 25 degree celsius. The optimal conditions for the production of penicillin G in 5-L fermentor were found as follows :pH of the medium was controlled in the range of 5.8-7.1, agitation rate was 400 rpm. with 1 vvm. aeration rate, 0.7 g/l phenylacetic acid was added after 24 hours of cultivation, continuous feeding of 15% (W/V) glucose solution at the rate of 5 ml/hour was done starting at 12 hours of cultivation and 0.45% (W/V) phenylacetic acid was applied at the rate of 20 ml/6 hours after 48 hours of cultivation. Under these conditions, 8,175 unit/ml of penicillin G was obtained at 144 hours of cultivation. According to these conditions, it was observed that reducing sugar, ammonia nitrogen and sulfate were not the limiting factor of the penicillin G production. The increase in feeding rate of precursor had no effect on the rate of penicillin G production. However, from the microscopic analyses revealed that at 144 hours of cultivation mycelium began to decompose corresponding to the reduction in efficiency of penicillin G production. Thus the limiting factor of penicillin G production was due to the physical condition of the mycelium. By using the conditions as described above, the penicillin G production by P. chrysogenum A 88 was increased from the initial of 3,570 units/ml to 8,175 units/ml.
