Co-fermentation of 1,3-propanediol and 2,3-butanediol from crude glycerol derived from the biodiesel production process by newly isolated Enterobacter sp.: Optimization factors affecting

Abstract

Co-fermentation of 1,3-propanediol and 2,3-butanediol from crude glycerol derived from biodiesel production process was investigated. The isolation of diols producer was firstly investigated. Factors including crude glycerol, yeast extract concentrations, and initial pH affecting diols were optimized using isolated microbes as the inoculum. Results determined strain MU-01 as the most efficient strain producing the highest concentration of diols. Sequence analysis revealed strain MU-01 as a member of Enterobacter sp. (Accession no. MT491125). Crude glycerol, yeast extract, and pH were influenced on 1,3-propanediol and 2,3-butanediol. Maximum 1,3-propanediol of 0.70 g/L was obtained at 10 g/L crude glycerol, 1 g/L yeast extract, and pH 8, respectively. The strain MU-01 also produced 2,3-butanediol at the concentration of 0.88 g/L under optimal conditions. The validation experiment indicated that the model was accurate, with a 2.85% difference between expected and observed values.