Abstract

In this report, the conditions for cell-recycle repeated-batch fermentation of recombinant flocculating industrial Saccharomyces Cerevisiae strain ZWA46-F2 was studied. Upon the residual sugar decreased to 20 g/L, half amount of total yeast cells was directly recycled in the subsequent batch fermentation without prior washing. The following conclusions were obtained: (i) it was appropriate to conduct 22 cycles of cell-recycle repeated-batch fermentation; and (ii) in comparison with the first batch, the highest alcohol yield was increased by 18.4%, the fermentation time was decreased by 18 hours, and the productivity was increased by 78.7%.

Keywords: Saccharomyces Cerevisiae; Recombinant flocculating yeast strain; Alcohol fermentation; Cellrecycle repeated-batch fermentation