Single cell protein from various chemically pretreated wood substrates using Chaetomium cellulolyticum

The growth behavior of Chaetomium cellulolyticum , a new cellulolytic fungus, has been examined in slurry fermentation systems using various chemically pretreated sawdusts from hardwoods as substrates. Both acid‐ and alkali‐pretreatment methods were used and the fermentation media included the spent pretreatment liquor in an attempt to concurrently maximize substrate utilization and minimize the biological oxygen demand (BOD) level in the process effluent. Diauxic growth patterns were found in the three cases studied, suggesting an initial utilization of soluble hemicellulose sugars followed by utilization of the insoluble cellulose. This behavior patterns was supported by separate growth experiments using the major sugars of hemicellulose as carbon sources. The organism was found to be a good convertor of both cellulose and hemicelluloses into single cell protein (SCP). In terms of rate and extent of protein production in the insoluble biomass product, acid pretreatment appears to be better than alkali pretreatment if the product is intended as ruminant feed.