[1, 3-propanediol production under salt stress]

Through studying the process of glycerol fermentation to 1, 3-propanediol(1, 3-PD) by Klebsiella pneumoniae, it was found that the cell growth and product (or by-product) production were under salt stress. Cell growth and product formation kept high rate at low salt concentration. High salt concentration led to low growth of cells, final concentration of 1, 3-PD and conversion from glycerol to 1, 3-PD, and, 1, 3-propanediol oxidoreductase activity decreased. When the salt concentration in 5 m3 bioreactor was controlled under appropriate manner, the concentration of 1, 3-PD production was markedly enhanced. The final 1, 3-PD concentration ,the conversion of glycerol to 1, 3-PD and productivity were 64 g/L, 61% and 2.1 g/(L x h).