Sugar beet diffusion juice and syrup as media for ethanol and levan production by Zymomonas mobilis.

摘要

Z.mobilis strain 113 S simultaneously produced ethanol and levan (up to 40-70 g/litre) in a sucrose medium. Z.mobilis also converted sucrose into ethanol and levan in batch fermentations using sugarbeet juice without additives. Syrup [thick juice] (65% sucrose), obtained after evaporation of sugarbeet juice in a beet sugar factory using conventional technology, was also an effective raw material for ethanol and levan production. Addition of yeast extract, with or without minerals (N, P, K and Mg) stimulated culture growth and product synthesis on thick juice. The potential for reuse of liquid fermentation products, after separation of levan and distillation of ethanol, was investigated. Recycled culture medium resulted in slightly diminished product synthesis and the osmolality of the medium increased.