FERMENTATIVE PRODUCTION OF 2,3-BUTANEDIOL - A REVIEW

The production of 2,3-butanediol by bacterial species continues to be of great interest because of its varied application. Two bacterial species, Bacillus polymyxa and Klebsiella pneumoniae have demonstrated potential for butanediol fermentation on a commercial scale. Klebsiella pneumoniae, owing to its broad substrate and cultural adaptability, is the most thoroughly investigated organism. It is generally recommended that natural resources of 'waste' cellulosic and hemicellulosic substrates be fermented, for the improvement of process economics. The process of diol fermentation is reportedly influenced by various nutritional and environmental parameters. The high boiling-point characteristic of 2,3-butanediol poses serious problems in recovery of diol from fermented slurry. Repeated solvent extraction and countercurrent-stream stripping have been recommended as the methods of choice for diol recovery.