Continuous production of cellulase in a fluidized-bed reactor by Pseudonomas fluorescens immobilized in hydrogel beads
At present, the most widely used microorganism for commercial production of cellulose is probably the filamentous fungus Trichoderma reesei. The T. reesei cellulose system is typically complete and highly productive but the solid-state culture involves complex media and substrate and an inducer which add to the production costs. There is considerable interest in isolating bacteria that produce cellulose enzymes which are more stable, have higher temperature optima, and broader pH optima. Bacterial cellulases may also exhibit greater substrate specificity and more favorable reaction kinetics. We feel that enzyme production could be significantly enhanced by increasing the concentration of active biomass in the reactor, and using organisms that take advantage of simpler media or do not require inducers for enzyme production. Our efforts to develop a more effective cellulose production system have focused on a modified bacterium and on immobilization and utilization of the microorganism in a high-productivity fluidized-bed reactor. The approach is to use a proprietary, cellulase-producing pseudomonad-like bacterium under development at Oak Ridge National Laboratory. The cellulose is constitutively produced and excreted by the bacterium in a minimal media with no requirement for inducers or special chemicals. This bacterium is then immobilized in a hydrogel bead that is used in a continuous fluidized-bed bioreactor. The cellulose can be recovered in downstream processing of the bioreactor effluent.
- Research Organization:
- Oak Ridge National Lab., TN (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC05-84OR21400
- OSTI ID:
- 10161963
- Report Number(s):
- CONF-940526-6; ON: DE94014105
- Resource Relation:
- Conference: 16. symposium on biotechnology for fuels and chemicals, Gatlinburg, TN (United States), 9-13 May 1994; Other Information: PBD: [1994]
- Country of Publication:
- United States
- Language:
- English
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