UBC Theses and Dissertations
Degradation of sawdust by Cellulomonas fimi enzymes Vondette, Nancy Anne
Cellulomonas find was grown on minimal media with casamino acids and yeast extract added. Avicel was found to be the best cellulosic carbon source for the production of cellulase enzymes. The Millipore Ultrafiltration System was found to be the most efficient method of concentrating the enzyme preparations. Unpretreated sawdust samples of four different softwood species were degraded between 12 and 16 percent over a 15-day treatment. Increasing the concentration of substrate lead to a lower percent degradation but a higher overall degradation. Chemical pretreatment did not appreciably increase degradability of the samples. Physical pretreatments decrease the degrada-bility of the sawdust samples. The lotech pretreatment, which is a combination of chemical and physical pretreatment, gives a substrate that is degraded by the Cellulomonas fimi enzyme preparation. The pretreatment makes 50% of the sample water soluble. In 3 days, a further 35% is degraded from large insoluble chunks into insoluble small particles which remain in suspension. There is 6% degraded into soluble state. This leaves only 9% of the initial sample left in the pellet. With longer incubation, one would expect the degradation to continue.
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