Aspergillus niger의 휴지균체에 의한 Gluconic Acid생성에 관한 연구

Studies on the Production of Gluconic Acid by Resting Cell System of Aspergillus niger

Aspergillus niger의 휴지균체법에 의한 glucose 로부터 gluconic acid 생산에 대해서 연구한 결과, gluconic acid 생산은 반응 pH, 온도, 기질농도, 통기조건, 금속 ions, 휴지균체의 보존상태 및 반응시간에 따라 크게 영향을 받았다. 휴지균체법에 의해서 glucose로부터 전환된 생성물질은 thin layer chromatography와 infrared spectrophotometer에 의해서 gluconic acid로 확인되었으며, glucose로부터 gluconic acid 생성반응에서는 $Mg^{++}$, S $n^{++}$의 첨가로 촉진효과를 보였으나, C $u^{++}$, H $g^{++}$, C$d^{++}$, A $g^{+}$ 및 Cyanide는 저해효과를 나타냈다. 휴지균체의 최적보존 조건으로는 0.05 M phosphate buffer(pH7.0)에서 -$25^{\circ}C$ 보존 시가제일 안정하였다. 휴지균체법에 의한 gluconic acid 생산은 발효법에 비해서 배양시간이 짧고 수율이 양호하고, 정제 시 회수가 간단할 뿐 아니라 균체의 반복사용이 가능하였다.

The production of gluconic acid from glucose by the resting cell system of Aspergillus niger was studied. It was found that the conversion products from glucose by the resting cell system were markedly influenced by the pH, temperature, substrate concentration, aeration, metal ions, cultivation time and storage conditions of the resting cells. Conversion products were identified as gluconic acid by the thin layer chromatography and infrared spectrophotometry. These conversions were greatly stimulated by addition of $Mg^{++}$, and S $n^{++}$, but showed inhibitory effects by C $u^{++}$, H $g^{++}$, C $d^{++}$, A $g^{+}$ and cyanide. For the optimum cell storage, it was effective to be kept at -$25^{\circ}C$ in 0.05M phosphate buffer solution of pH 7.0. The gluconic acid production by the resting cell system was more effective than those of the fermentation with respect to cultivation time, yield, recovery and re-use of the cell.l.l.l.l.l.l.