Effects of Concentrations of Ammonium Sulphate and pH Control on Fermentation of Glutathione by Candida utilis SIPI-60336

The concentrations of reducing sugar and amino nitrogen as well as pH were controlled for the production of glutathione by Candida utilis SIPI-60336 in a 15L stirred fermentor. The effects of different cultivation modes on glutathione production were studied. High production of both yeast cell and glutathione were all realized in the cultivation mode of high cell-density culture (HCDC). Intracellular glutathione content and the maximum dry cell weight could reach 830mg/L and 41.5g/L when cells were incubated for 48h in a medium containing reducing sugar (10g/L), amino nitrogen (60mg/100ml) at pH 4.5.