초록
<P>A thin-shell silk cocoon (TSC), a residual from the silk industry, was used as an alternative nitrogen (N-) source in ABE fermentation by <I>Clostridium acetobutyricum</I> ATCC 824. The experimental studies were performed in batch fermentation at 35 °C and pH 5.0. The results were compared with the system using yeast extract (YE) as N-source. It was shown that TSC fragments (TSCf) could be used as a cheap substitute for YE for a certain amount. Under optimum conditions, total solvent of 22.3 g/L (12.7 g/L butanol, 8.0 g/L acetone and 1.5 g/L ethanol) was obtained from the ABE fermentation using the mixture of TSCf and YE as N-sources. The ABE productivity and conversion yield were 0.15 g/L/h and 0.30 g/g sugar consumption, respectively.</P>