Production of 2,3-butanediol from fructose by Bacillus licheniformis

Bulgarian isolate Bacillus licheniformis strain 24 possesses considerable advantages as a producer of 2,3-butanediol (2,3-BD) with potential for industrial implementation – the strain is non-pathogenic, has a broad substrate spectrum, cellulolytic activity, and ability to convert glucose, cellobiose, and mannose in 2,3-BD with high amounts, yield, and productivity. The present study aims to investigate the ability of B. licheniformis 24 to produce 2,3- butanediol (2,3-BD) from fructose. In optimized media and process parameters, in batch fermentation from 200 g/L fructose at 33rd hour of fermentation was achieved 83.5 g/L 2,3- BD with yield and productivity of 0.46 g/g and 2.53 g/L/h, respectively. In fed-batch mode from a total of 370 g/L fructose, the obtained concentration of 2,3-BD after 72 hours of fermentation was 156.1 g/L with a yield of 0.42 g/g and productivity 2.17 g/L/h – one of the best results for 2,3-BD production from any substrate obtained to date. This indicates that B. licheniformis 24 would be extremely useful in the bioconversion of fructose-containing wastes or feedstocks for economical 2,3-BD production.