Valorization of glycerol into 1,3-propanediol and organic acids using biocatalyst Saccharomyces cerevisiae

This study investigates commercially available yeasts for the fermentation of glycerol into valuable products. Instant baker's yeast showed higher potential for converting glycerol into 1,3-PDO and different organic acids. It has been observed that yeast also produced butyric acid along with the 1,3-PDO, which is primarily produced by chemical synthesis. The co-production of butyric acid and 1,3-PDO from glycerol could be cost-effective. The fermentation of glycerol as a sole carbon at the temperature of 25 °C produced 0.13 g/g of 1,3-PDO and 0.60 g/g of butyric acid. The co-fermentation of glycerol and different sugars was also studied. When xylose was used as a co-substrate, the yield of 1,3-PDO and butyric acid increased. Co-substrate increases the intracellular reducing equivalents (NADH) and is required to form more reduced products from glycerol. When xylose was used as a co-substrate, the maximum yield of 1,3-PDO and butyric acid reached 0.15 and 0.70 g/g, respectively.