균류키토산의 균체생산에서 기질농도 최적화에 관한 연구

Optimization of Substract Concentration in Cell Production of Fungal Chitosan

In the process of producing chitosan from crustacean shell, the use of excessive acid and alkli is causing the problems of environmental pollution and of production cost. In this study, one way to solve these problems is to cultivate fungi, then, to extract chitosan from the cell wall. By means of flask incubation and batch cultivation, the optimum cultivation conditions for mass production of continuous cultivation was found. Four strains used for the production of fungal chitosan were Gongronella butleri IF08080, Absidia coerulea IF05301, Rhizopus delemar IF04775, Mucor tuberculisporus IF09256. In flask incubation to select strain of producing much chitosan by means of experiment of the effect of initial pH, Absidia coerulea IFO 5301 had highest yield in FCs, 258.1 ± 47.3 mg/200 mℓl at pH 6.5. In flask incubation under the optimum cultivation condition, temperature 27∘C, culture time 6days, glucose 2%, peptone 1%, (NH4)2 SO4 0.5%, K2 HPO4 0.1 %, Nacl 0.1 %, MgSO4ㆍ7H2O 0.05%, CaCl2ㆍ2H2O 0.01 %, the yield of DCW brought the highest yields. In batch bioreactor, the optimum cultivation condition was that cell suspended solution was 70 mℓ, aeration rate 0.5 l/min, agitation rate 800 rpm, culture time 36 hr. In continuous bioreactor, the optimum substrate flow rate was 4 ι/day.