Thiamine Hydrochloride → L-Glutamine

Participants

Reaction Conditions

Reaction Steps

Brevibacterium flavum AJ 3409 (FERM-BP 662) was inoculated on agar plate medium containing 1% yeast extract, 1% peptone, 0.5% sodium chloride and 0.5% glucose followed by culturing at 31° C. for 24 hours. In 30 Sakaguchi flasks, each having a 500 ml volume, were charged 25 ml each of medium (pH 7.0) composed of 4% glucose, 0.1% potassium phosphate, 0.04% magnesium sulfate, 0.001% iron sulfate, 0.2% ammonium sulfate, 0.4% urea, 4 μg/1 biotin, 100 μg/l vitamin B1 and 0.035% (calculated as total nitrogen) of soybean protein hydrolysate. After sterilization by heating at 121° C. for 15 minutes, the temperature was lowered to room temperature and one platinum loopful of the cells of Brevibacterium flavum AJ 3409 previously grown on the agar plate medium was inoculated on the sterilized medium. By shake culturing at 31° C. for 24 hours, a seed culture broth was prepared. In a fermentation tank of 20 liter volume, was charged 10 liters of medium (pH 7.0) composed of 10% glucose, 0.4% potassium phosphate, 0.06% magnesium sulfate, 0.002% iron sulfate, 5% ammonium sulfate, 8 μg/l biotin, 500 μg/l vitamin B1 and 0.056% (calculated as total nitrogen) of soybean protein hydrolysate. After sterilization by heating at 121° C. for 20 minutes, the temperature was lowered to room temperature and the seed culture broth previously cultured in the flask was added to the medium followed by culturing under conditions: culture temperature at 30° C., controlled pH of 6.5, aeration amount of 1/2 vvm, a stirring number of 600 rpm and inner pressure of 0.2 kg/cm2. Immediately before the glucose in the culture broth was consumed, a solution (sterilized) containing 45 g/l of glucose was added to the culture tank to replenish the glucose concentration in the culture broth and always maintain a concentration of 0.1 to 1.5%. At and from the time period when the amount of accumulated glutamine exceeded its solubility and the crystals of glutamine began to crystallize in the culture broth, a part of the culture broth was aseptically taken out of the system then passed through a small-sized liquid cyclone to isolate the crystals. Then the culture broth was returned to the culture tank. Culture for 100 hours by this method gave 1.1 kg (moisture content of 16.6%) of a slurry of glutamine crystals and 15 liters of the culture broth containing 5.2% glutamine. The obtained culture broth was crystallized by concentration. The crystals were isolated and combined with the slurry of crystals obtained during the culture. By repeating dissolution and crystallization three times, 1.36 kg of glutamine crystals was obtained in a high purity.

Provenance & Evidence