Purification of arabitol from fermentation broth of Debaryomyces hansenii using glycerol as substrate

摘要

BACKGROUND: Arabitol has many potential industrial applications and it can be produced by fermentation from glycerol, a major byproduct of biodiesel industry. This work aims at developing a new process for collecting and purifying arabitol from the broth of osmophilic Debaryomyces hansenii containing arabitol, unconsumed glycerol, and other minor impurities. RESULTS: The process developed and optimized in this study had the following steps: first, the broth supernatant was treated with 8gL-1 activated carbon at 30°C and pH 6 for removal of colored organics and some impurities. Then glycerol was selectively removed by acetone extraction at 30°C. The acetone amount was optimized according to the measured solubility data of simulative glycerol-xylitol-acetone systems and real fermentation broth. The glycerol-removed remainder was next extracted for arabitol with butanol (90% of supernatant volume) at 90°C. White arabitol crystals were collected from the cooled butanol extract. The overall recovery and purity of arabitol crystals were 66% and 95%, respectively. CONCLUSION: Successful arabitol purification was achieved with an optimized process. Fundamental phase equilibrium data of glycerol-xylitol-acetone systems were obtained. The process developed would prove valuable for arabitol production and potentially for separation of other polyols.