Title: Isolation of New Strains of Bacteria Able to Synthesize 1,3-Propanediol from Glycerol
Abstract: The natural environment is inhabited by many species that exhibit very specific metabolic activities that may find industrial applications. The aim of the study was to select non-pathogenic cultures of bacteria of the genus Clostridium and lactic acid bacteria able to convert glycerol into 1,3-propanediol (1,3-PD). Another aim of this study was to identify the isolates that best produced 1,3-propanediol both from pure and crude glycerol. The most efficient strains identified (Cl. butyricum) were analysed on a bioreactor scale. The aim was to determine temperature conditions on the efficiency and duration of 1,3-PD synthesis. The species Clostridium were identified using amplification of the 16S rRNA coding sequence. A total of 123 isolates (of the genus Clostridium and lactic acid bacteria) were isolated; a vast majority of these were able to synthesize 1,3-PD. The best results were obtained for Cl. butyricum strain DSP1, which was isolated from the rumen of a cow fed with glycerol. The strain efficiency using pure glycerol on bioreactor scale 0.65 mol/mol of glycerol at a temperature of 38℃ and a constant pH of 7.0.