1,3-Propanediol production in a two-step process fermentation from renewable feedstock

Abstract

In this work, the production of 1,3-propanediol from glucose and molasses was studied in a two-step process using two recombinant microorganisms. The first step of the process is the conversion of glucose or other sugar into glycerol by the metabolic engineered Saccharomyces cerevisiae strain HC42 adapted to high (>200 g l(-1)) glucose concentrations. The second step, carried out in the same bioreactor, was performed by the engineered strain Clostridium acetobutylicum DG1 (pSPD5) that converts glycerol to 1,3-propanediol. This two-step strategy led to a flexible process, resulting in a 1,3-propanediol production and yield that depended on the initial sugar concentration. Below 56.2 g l(-1) of sugar concentration, cultivation on molasses or glucose showed no significant differences. However, at higher molasses concentrations, glycerol initially produced by yeast could not be totally converted into 1,3-propanediol by C. acetobutylicum and a lower 1,3-propanediol overall yield was observed. In our hand, the best results were obtained with an initial glucose concentration of 103 g l(-1), leading to a final 1,3-propanediol concentration of 25.5 g l(-1), a productivity of 0.16 g l(-1) h(-1) and 1,3-propanediol yields of 0.56 g g(-1) glycerol and 0.24 g g(-1) sugar, which is the highest value reported for a two-step process. For an initial sugar concentration (from molasses) of 56.2 g l(-1), 27.4 g l(-1) of glycerol were produced, leading to 14.6 g l(-1) of 1.3-propanediol and similar values of productivity, 0.15 g l(-1) h(-1), and overall yield, 0.26 g g(-1) sugar.

The ability of Clostridium bifermentans strains to lactic acid biosynthesis in various environmental conditions

“…Accordingly, it is necessary to find a new effective method to utilized this amount of crude glycerol. The research on production 1,3-PD from crude glycerol by microbiological way is extensively described worldwide e.g., (Hiremath et al 2011; Mendes et al 2011; Vaidyanathan et al 2011; Chatzifragkou et al 2011; Wilkens et al 2012; Ringel et al 2012), but only a few papers concern the production of lactic acid from this by-product, and moreover, publications concentrate mainly on genetic engineered strains (Posada et al 2012; Ruhal & Choudhury 2012); at the same time only a few papers discuss lactic acid production from other renewable resources (Hofvendahl & Hahn-Hägerdal 2000; Yadav et al 2011). During our work it occurred that Cl.…”

1,3‐propanediol production from glucose by mixed‐culture fermentation of Zygosacharomyces rouxii and Klebsiella pneumonia

“…Compared with other microbial producing method for 1,3-propanediol using crude glycerol [12,13] or two-stage from glucose [14,15], the yield is much lower. To our knowledge, no related study on producing 1,3-propanediol from glucose using a mixed culture of these two species has been reported before.…”

“…Recently, the sharply enlarged manufacture of the polytrimethylene terephthalate (PTT) has stimulated the global interest in producing 1,3-propanediol by the fermentative route. Furthermore, the two-stage process for producing 1,3-propanediol from glucose have been reported, where the glucose was converted first to glycerol using recombinant Escherichia coli or yeast, and then the glycerol was converted to 1,3-propanediol by K. pneumoniae or Clostridium acetobutylicum [14,15] . Most of the previous studies have used pure glycerol.…”

“…For example, the glycerol broth from the yeast fermentation and biodiesel-derived raw glycerol as the substrate have been used for 1,3-propanediol production [7][8][9][10][11][12][13]. Furthermore, the two-stage process for producing 1,3-propanediol from glucose have been reported, where the glucose was converted first to glycerol using recombinant Escherichia coli or yeast, and then the glycerol was converted to 1,3-propanediol by K. pneumoniae or Clostridium acetobutylicum [14,15] .…”

Microbial production of short chain diols

“…No known natural organism ferments sugars directly to 1,3-PDO. The attempts using sugars as substrate have been made with either multistage fermentations involving a combination of microorganisms [73,74] or genetically engineered microorganisms [8,75] carrying genes for the conversion of sugar to glycerol and then to 1,3-PDO.…”