Acetic acid-friend or foe in anaerobic batch conversion of glucose to ethanol by Saccharomyces cerevisiae?

• The permissible region of growth of Saccharomyces cerevisiae on glucose under anaerobic conditions was determined as a function of both pH and the concentration of added acetic acid to the medium. In the absence of acetic acid, growth was possible at a pH as low as 2.5, whereas a total acetic acid addition of 10 gl-1 increased the minimum allowable pH for growth to 4.5. The results showed that the concentration of the undissociated form of acetic acid should not exceed 5 gl-1 in the medium for growth to occur. The addition of acetic acid had a profound effect on growth energetics, thereby leading to an increased ethanol yield on glucose. At a concentration of 3.3 gl-1 of undissociated acetic acid, the ethanol yield was 20% higher than without added acetic acid. Furthermore, the biomass and glycerol yields decreased by 45 and 33%, respectively.The permissible region of growth of Saccharomyces cerevisiae on glucose under anaerobic conditions was determined as a function of both pH and the concentration of added acetic acid to the medium. In the absence of acetic acid, growth was possible at a pH as low as 2.5, whereas a total acetic acid addition of 10 g l-1 increased the minimum allowable pH for growth to 4.5. The results showed that the concentration of the undissociated form of acetic acid should not exceed 5 g l-1 in the medium for growth to occur. The addition of acetic acid had a profound effect on growth energetics, thereby leading to an increased ethanol yield on glucose. At a concentration of 3.3 g l-1 of undissociated acetic acid, the ethanol yield was 20% higher than without added acetic acid. Furthermore, the biomass and glycerol yields decreased by 45 and 33%, respectively.

Ämnesord

TEKNIK OCH TEKNOLOGIER  -- Industriell bioteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Industrial Biotechnology (hsv//eng)

Nyckelord

Ethanol

Glycerol

Growth energetics

PH

Yeast

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)