Utilization of d-xylose as carbon source for production of bacterial cellulose

Utilization of d-xylose as carbon source for production of bacterial cellulose was studied. Seventeen strains of acetic acid bacteria were screened for their cellulose productivity in d-glucose, d-xylose, and d-xylose/d-xylulose mixed media, respectively. d-Xylose was not well metabolized by any bacterial strains that exhibited high cellulose production in d-glucose medium. Consequently, bacterial cellulose production in d-xylose medium was unsuccessful. d-Xylose, however, became utilizable substrate for bacterial strains if xylose-isomerase was added to the medium. Acetobacter xylinus IFO 15606 was the best cellulose producer in d-xylose/d-xylulose mixed medium, so cultural conditions were studied for enhanced cellulose production. With pH controlled, the strain could produce cellulose at a yield exceeding 0.3 g per 100 ml of d-xylose/d-xylulose mixed medium, which was comparable to the yields in d-glucose medium by excellent producers in the literature.