초록
<P><B>Abstract</B></P> <P>The growth of <I>Debaryomyces nepalensis</I> on mixed substrates in batch culture follows diauxic pattern of completely utilizing glucose during the first exponential growth phase, followed by an intermediate lag phase and a second exponential growth phase consuming xylose. The present study deals with the development of a cybernetic mathematical model for prediction of xylitol production in the presence of co-substrate. To experimentally validate the model, defined media supplemented with different concentration of co-substrate were tested and compared with production on single carbon source. High xylitol yield of 0.73 g g<SUP>−1</SUP> was achieved when supplemented with 10 g L<SUP>−1</SUP> of glucose in the xylose-rich media. The proposed model could adequately describe the diauxic growth, sequential utilization of substrates and production of xylitol under various ratio of co-substrate. The model could be used as a tool to assess the influence of co-substrate (glucose) concentration added to the media on xylitol production.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Cybernetic model was developed for xylitol production in batch reactor. </LI> <LI> Influence of co-substrate on growth and xylitol production were evaluated. </LI> <LI> Preference of substrate utilization: glucose > xylose> arabinose. </LI> <LI> Low initial levels of glucose enhance the xylitol yield and production. </LI> <LI> Accurate prediction of xylitol yield by this cybernetic model. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>