biomass, butiftoo much is added, it may accumulate in the medium
leading to foaming and wasted decanoic acid. A fermentation was
conducted by feeding glucose (50%W/V) and a mixture of decanoic
acid and acetic acid (55:45V/V) to achieve a decanoic acid:acetic
acid:glucose mass ratio of 3:3:4 at a of about 0.15 h−1. The ammonium
and phosphate concentrations remained atlevels that neither
limited nor inhibited growth as in previous studies with nonanoic
acid (Sun et al., 2007a,b). Concentrations of decanoic acid and glucose
were low throughout most of the fermentation until first
glucose then decanoic acid began to accumulate indicating that the
bacterium was no longer able to grow at a of 0.15 h−1 around
25.5 h (Fig. 1).
Starting at 16 h, some pure oxygen was required to maintain the
DO (data not shown) at 40% of saturation. The CO2 production rate
(data not shown)increased exponentially until decanoic acid began
to accumulate, at which time (25.5 h) it decreased rapidly. This
was followed by uncontrolled foaming. The maximum dry biomass