RESUMO
D-xylose is a metabolizable carbon source for several non-Saccharomyces species, but not for native strains of S. cerevisiae. For the potential application of xylose-assimilating yeasts in biotechnological processes, a deeper understanding of pentose catabolism is needed. This work aimed to investigate the traits behind xylose utilization in diverse yeast species.The performance of nine selected xylose-metabolizing yeast strains was evaluated and compared across three oxygenation conditions. Oxygenation diversely impacted growth, xylose consumption and product accumulation. Xylose utilization by ethanol-producing species such as Spathaspora passalidarum and Scheffersomyces stipitis was less affected by oxygen restriction than other xylitol-accumulating species such as Meyerozyma guilliermondii, Naganishia liquefaciens and Yamadazyma sp., for which increased aeration stimulated xylose assimilation considerably. S. passalidarum exhibited superior conversion of xylose to ethanol and showed the fastest growth and xylose consumption in all three conditions. By performing assays under identical conditions for all selected yeasts, we minimize bias in comparisons, providing valuable insight into xylose metabolism and facilitating the development of robust bioprocesses.
