anaerobic bacteria were proposed to play a major role in oxygen
consumption in the early stage of the static aerobic batch culture,
which allows the growth of cellulolytic clostridia in the later anoxic
condition [11,12]. In addition, the non-cellulolytic members also
contribute to cellulose degradation by controlling pH and consuming
metabolites, which would otherwise deteriorate the cellulolytic
activity e.g. by enzyme inhibition and metabolite repression.