THE TECHNOLOGICAL CONDITIONS OF PRODUCING 2-KETO-LGULONIC ACID FROM D-GLUCOSE BY DIRECT FERMENTATION / 微生物学通报

ABSTRACT

2-Keto-L-gulonic acid (2-KLG), the precurcor of L-ascorbic acid synthesis, was prepared directly from D-glucose by tandem fermentation. In the first step fermentation Erwinia sp. SCB 247 translated D-glucose to 2,5-diketo-D-gluconate (2,5-DKG), which accumenlated 180 mg 2,5-DKG per ml in the broth. In the second step fermentation Corynebacterium sp. SCB 3058 reduced 2,5-DKG to 2-KLG, which accumulated 35 mg 2-KLG per ml in the broth. This reductive fermentation was obtained under aerobic conditions by adding a hydrogen donor such as glucose.The average yield of five batches fermentation was 56.3 mol%, from D-glucose to 2-KLG in 10 L fermentor.