Influence of aeration and pH on xylose fermentation to ethanol by Pichia stipitis
Roberto, I.C.; Mancilha, I.M. de; Felipe, M.G.A.; Silva, S.S.; Sato, S.
Arquivos de Biologia e Tecnologia 37(1): 55-63
The conversion of xylose into ethanol by Pichia stipitis was studied in relation to pH and degree of oxygenation; the latter was varied using several combinations of agitation rate and ratio between volume of flasks and volume of the medium (VF:VM). Ethanol yields were found to depend on the aeration conditions used. Best yields were obtained in flasks agitated at 100 and 150 r.p.m. for respective VF:VM ratios of 5.0 and 2.5. Such conditions gave ethanol yields of ~0.35 g/g, which corresponds to 70% of the theoretical value.