[Microbiological transformation of carbohydrates. Glucose isomerization into fructose by washed cells of Streptomyces sp. strain 29].

Glucose-fructose transformation by washed and packed cells of Streptomyces sp. 29 was studied. The cells grown on the nutrient medium containing xylose and Co and Mg salts were capable to perform glucose-fructose isomerization. The cellular activity depended in a great degree on the temperature, pH and initial glucose concentration; to a lesser extent on Co and Mg ions present in the incubation mixture, and did not depend on the age of the culture (within 8-69 hours). The activity reached its maximum at 70-80 degrees C, pH 7.0 and a low concentration of glucose (10(-3) M). Under these conditions the yield of fructose was 50% from the initial glucose concentration (or 100% from the theoretical value). Washed cells of Streptomyces sp. 29 packed into a thermally controlled column continuously transformed glucose to fructose during 24 days with a yield of 30-44%.