Hits:
Indexed by:期刊论文
Date of Publication:2014-03-01
Journal:ENGINEERING IN LIFE SCIENCES
Included Journals:SCIE、EI、Scopus
Volume:14
Issue:2
Page Number:108-117
ISSN No.:1618-0240
Key Words:Aqueous two-phase systems; Bio-based chemicals; Diols; Organic acids; Salting-out extraction
Abstract:The possibility of creating a biorefinery using inexpensive biomass has attracted a great deal of attention, which is mainly focused on the improvement of strains and fermentation, whereas few resources have been spent on downstream processing. Bio-based chemical downstream processing can become a bottleneck in industrial production because so many impurities are introduced into the fermentation broth. This review introduces a technique referred to as salting-out extraction, which is based on the partition difference between chemicals in two phases consisting of salts and polymers or hydrophilic solvents, hydrophobic solvents, and amphipathic chemicals. The effects of solvents and salts on the formation of two phases were discussed, as was the use of this method to recover bio-based chemicals. This review focused on the separation of hydrophilic chemicals (1,3-propanediol, 2,3-butanediol, acetoin, and lactic acid) from fermentation broths. Diols could be recovered at a high yield from fermentation broths without pretreatment especially with a hydrophilic solvent-based system, whereas the recovery of organic acids was slightly lower. Most of the impurities (cells and proteins) were removed during the same step. Extractive fermentations were also used for polymer-based aqueous two-phase systems.