Glycerol production by reusing free Candida glycerinogenes cells in repeated batch fermentation was studied.The results showed that the suitable concentration of KH2PO4 in the re-inoculation medium was 0.1 g·L-1

lower than KH2PO4 of 0.4 g·L-1 in the first fermentation medium.When the residual glucose concentration decreased to 10 g·L-1

yeast cells from sterile centrifugation with the activity high enough for the next cycle could be directly recycled for the next batch fermentation.After 15 cycles of re-inoculation

average glycerol concentration

yield and productivity were 138.69 g·L-1

60.17% and 2.31 g·L-1·h-1

with an increase of 15.74%

15.48% and 39.16%

respectively

compared with these in the first batch fermentation.Although yeast cells decayed severely in the fifteenth cycle

12—14 cycles of repeated batch fermentation were possible.