Co-encapsulation of Saccharomyces cerevisiae and enzymes for the efficient fermentation of D-Xylose in the production of fuel ethanol from cellulosic biomass
Conference
Frederick, B, Andreescu, S. (2008). Co-encapsulation of Saccharomyces cerevisiae and enzymes for the efficient fermentation of D-Xylose in the production of fuel ethanol from cellulosic biomass
. ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY
Frederick, B, Andreescu, S. (2008). Co-encapsulation of Saccharomyces cerevisiae and enzymes for the efficient fermentation of D-Xylose in the production of fuel ethanol from cellulosic biomass
. ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY
The necessity for alternative fuel sources is of increasing concern and one such option is the use of ethanol derived from plant matter. Cellulose and hemicellulose account for approximately 70% of the dry mass of typical plant and tree matter. From this, a significant proportion of the sugars are pentoses, such as xylose, which cannot be fermented by currently available non-GMO industrial yeast strains. These strains are only capable of fermenting hexose sugars making the process economically limited. In this presentation, we report the co-immobilization of standard Saccharomyces cerevisiae yeast along with appropriate enzymes such that the encapsulated combination will have both xylose and hexose fermentation capabilities. We describe the fabrication and characterization of core-shell structures with appropriate biomolecules entrapped inside a liquid core, as well as the study of stability, optimization of experimental conditions, and conversion yields. Co-encapsulation of the yeast with enzyme provided a sufficiently high concentration of enzyme for efficient xylose conversion to ethanol while lowering the cost of creating such a high concentration of biomaterial in bulk solution. These core-shell microcapsules are stable enough for multiple use, lowering economic costs. They also provide a protective micro-environment for yeast when in dilute acid-hydrolyzates, and opportunities to conduct continuous-flow fermentation. In addition, other enzymes can be incorporated to allow both enzymatic hydrolysis of cellulose and hemicellulose, and fermentation of other pentose sugars. The method provides a simple and economical way for improving the efficiency and conversion yield for both cellulose and hemicellulose sugar fermentation, from cellulosic biomass to ethanol.
