Abstract
Fermentation of sugars released from lignocellulosic biomass (LCMs) is a sustainable option for the production of bioethanol. LCMs release fermentable hexose sugars and the currently non-fermentable pentose sugars; ethanol yield from lignocellulosic residues is dependent on the efficient conversion of available sugars to ethanol, a side-product of the process is acetic acid production. Presence of acetic acid reduced metabolic output and growth when compared with controls; however, it was observed that incubation with proline had a protective effect, which was proline specific and concentration dependent; the protective effect did not extend to furan or phenolic stressed yeast cells. Proline accumulating strains displayed tolerance to acetic acid when compared with background strains, whereas, strains with a compromised proline metabolism displayed sensitivity. Sensitivity to weak acids appears to be reduced with the addition of proline; proline is an imino acid freely available as a nitrogen source in the aerobic phase of fermentations. Yeast strains with higher intracellular proline concentrations would be desirable for industrial bioethanol fermentations.
| Original language | English |
|---|---|
| Pages (from-to) | 641-652 |
| Number of pages | 12 |
| Journal | Antonie van Leeuwenhoek, International Journal of General and Molecular Microbiology |
| Volume | 105 |
| Issue number | 4 |
| Early online date | 6 Feb 2014 |
| DOIs | |
| Publication status | Published - 1 Apr 2014 |
| Externally published | Yes |
