In order to evaluate the behaviour of bacteria in relation to
the total and individual monosaccharides content of the culture
media during BC production using DOR40, glucose, fructose
and xylose contents were analysed.
The results obtained (Fig. 2) show that while BC produced
increased overtime until 0.8 ' 0.04 g L"1
, the concentration in glucose decreased linearly from 10 to 2 g L"1
. Fructose
(1.55 ' 0.08 g L"1
) seemed to have been nearly depleted by
bacteria, during the first 30 h and the concentration of xylose
remained roughly constant along the assay. The BC production
presented a lag phase in the first 24 h and a linear growth
until 72 h when the production entered in a deceleration
phase, probably due to the lack of nutrients. However, there
was still about 2 g L"1 glucose in the culture medium after 96 h
which may suggest that content in sugars was not the limiting
factor.