Microbial production of D-lactic acid from dried distillers grains with solubles

Mohd Zaini, N. A. B., Chatzifragkou, A. ORCID: https://orcid.org/0000-0002-9255-7871 and Charalampopoulos, D. ORCID: https://orcid.org/0000-0003-1269-8402 (2019) Microbial production of D-lactic acid from dried distillers grains with solubles. Engineering in Life Sciences, 19 (1). pp. 21-30. ISSN 1618-2863 doi: 10.1002/elsc.201800077

Abstract/Summary

D-Lactic acid production is gaining increasing attention due to the thermostable properties of its polymer, poly-D-lactic acid (PDLA). In this study, Lactobacillus coryniformis subsp. torquens, was evaluated for its ability to produce D-lactic acid using Dried Distillers Grains with Solubles (DDGS) hydrolysate as the substrate. DDGS was first subjected to alkaline pretreatment with sodium hydroxide to remove the hemicellulose component and the generated carbohydrate-rich solids were then subjected to enzymatic hydrolysis using cellulase mixture Accellerase® 1500. When comparing separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF) of L. coryniformis on DDGS hydrolysate, the later method demonstrated higher D-lactic acid production (27.9 g/l, 99.9% optical purity of D-lactic acid), with a higher glucose to D-lactic acid conversion yield (84.5%) compared to the former one (24.1 g/l, 99.9% optical purity of D-lactic acid). In addition, the effect of increasing the DDGS concentration in the fermentation system was investigated via a fed-batch SSF approach, where it was shown that the D-lactic acid production increased to 38.1 g/l and the conversion yield decreased to 70%. In conclusion, the SSF approach proved to be an efficient strategy for the production of D-lactic acid from DDGS as it reduced the overall processing time and yielded high D-lactic acid concentrations.

Item Type	Article
URI	https://reading-clone.eprints-hosting.org/id/eprint/79714
Item Type	Article
Refereed	Yes
Divisions	Life Sciences > School of Chemistry, Food and Pharmacy > Department of Food and Nutritional Sciences > Food Research Group
Publisher	Wiley
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