The research described in this thesis was aimed at understanding how particle
size, porosity, and enzyme accessible surface area influence the rate of saccharification
of microcrystalline cellulose. Microcrystalline cellulose (MCC) is a commonly used
substrate for the study of cellulolytic enzymes. MCC preparations of different particle
size are commercially available. In this study, MCC preparations having average particle
sizes of 20, 50, and 90 μm were analyzed with respect to their enzyme accessible surface
area, chemical and physical properties and rates of enzymatic saccharification.
Saccharification studies were done using a commercially available cellulase preparation
from Trichoderma reesei. Pore volume distributions were determined from solute
exclusion experiments. Internal surface areas were calculated based on the application of
the lamellae model to the pore volume distribution data. External surface areas were
calculated based on the average particle size of each MCC preparation assuming that the
particles could be represented as solid spheres. The different MCC preparations were
found to have nearly equivalent enzyme accessible surface areas per unit weight. Greater
than 99 % of the total enzyme accessible surface area for each MCC preparations was
found to be within the porous structure of the particles. Enzymatic saccharification
experiments demonstrated that the smaller particle size MCCs were more readily
digested than those of larger particle size. The similarity of the three MCC preparations
with respect to chemical and physical properties (other than particle size), pore volume
distribution, and total enzyme accessible surface area suggests that a rate limiting factor
in the enzymatic digestion of MCC is a resistance attributable to diffusion within the
capillary network of these insoluble substrates. / Graduation date: 1996
| Identifer | oai:union.ndltd.org:ORGSU/oai:ir.library.oregonstate.edu:1957/25991 |
| Date | 30 May 1995 |
| Creators | Tantasucharit, Usicha |
| Contributors | Penner, Michael H. |
| Source Sets | Oregon State University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis/Dissertation |
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