Enhancing the Enzymatic Hydrolysis of Cellulosic Materials Using Simultaneous Ball Milling
Part of the
Applied Biochemistry and Biotechnology
book series (ABAB)
One of the limiting factors restricting the effective and efficient bioconversion of softwood-derived lignocellulosic residues is the recalcitrance of the substrate following pretreatment. Consequently, the ensuing enzymatic process requires relatively high enzyme loadings to produce monomeric carbohydrates that are readily fermentable by ethanologenic microorganisms. In an attempt to circumvent the need for larger enzyme loadings, a simultaneous physical and enzymatic hydrolysis treatment was evaluated. A ball-mill reactor was used as the digestion vessel, and the extent and rate of hydrolysis were monitored. Concurrently, enzyme adsorption profiles and the rate of conversion during the course of hydrolysis were monitored. α-Cellulose, employed as a model substrate, and SO2-impregnated steam-exploded Douglas-fir wood chips were assessed as the cellulosic substrates. The softwood-derived substrate was further posttreated with water and hot alkaline hydrogen peroxide to remove >90% of the original lignin. Experiments at different reaction conditions were evaluated, including substrate concentration, enzyme loading, reaction volumes, and number of ball beads employed during mechanical milling. It was apparent that the best conditions for the enzymatic hydrolysis of α-cellulose were attained using a higher number of beads, while the presence of air-liquid interface did not seem to affect the rate of saccharification. Similarly, when employing the lignocellulosic substrate, up to 100% hydrolysis could be achieved with a minimum enzyme loading (10 filter paper units/g of cellulose), at lower substrate concentrations and with a greater number of reaction beads during milling. It was apparent that the combined strategy of simultaneous ball milling and enzymatic hydrolysis could improve the rate of saccharification and/or reduce the enzyme loading required to attain total hydrolysis of the carbohydrate moieties.
Index EntriesCellulose hydrolysis cellulose enzyme adsorption ball mill reactor softwood enzymatic hydrolysis steam explosion bioconversion
Wyman, C. E. (1996), Handbook on Bioethanol—Production and Utilization
, Taylor and Francis, Washington, DC.Google Scholar
Boussaid, A. and Saddler, J. N. (1999), Enzyme Microb. Technol.
, 138–143.CrossRefGoogle Scholar
Ramos, L. P., Breuil, C., and Saddler, J. N. (1992), Appl. Biochem. Biotechnol.
, 37–47.CrossRefGoogle Scholar
Mansfield, S. D., Mooney, C., and Saddler, J. N. (1999), Biotechnol. Prog.
, 804–816.PubMedCrossRefGoogle Scholar
Bungay, H. (1992), Enzyme Microb. Technol.
, 501–507.CrossRefGoogle Scholar
Saddler, J. N., Brownell, H. H., Clermont, L. P. and Levitn, N. (1982), Biotechnol. Bioeng.
, 1389–1402.PubMedCrossRefGoogle Scholar
Eklund, R., Glabe, M., and Zacchi, G. (1990), Enzyme Microb. Technol.
, 225–228.CrossRefGoogle Scholar
Gregg, D. and Saddler, J. N. (1996), Biotechnol. Bioeng.
, 375–383.PubMedCrossRefGoogle Scholar
Ryu, S. K. and Lee, J. M. (1983), Biotechnol. Bioeng.
, 53–65.PubMedCrossRefGoogle Scholar
Kelsey, R. G. and Shafizadeh, F. (1980), Biotechnol. Bioeng.
, 1025–1036.CrossRefGoogle Scholar
Maekawa, E. (1996), Wood Sci. Technol.
, 133–139.CrossRefGoogle Scholar
Wu, M. M., Chang, K., Gregg, D. J., Boussaid, A., Beatson, R. P. and Saddler, J. N. (1999), Appl. Biochem. Biotechnol.
, 47–54.CrossRefGoogle Scholar
Henley, R. G., Yang, R. Y. K. and Greenfield, P. F. (1980), Enzyme Microb. Technol.
, 206–208.CrossRefGoogle Scholar
Katz, M. and Reese, E. T. (1968), Appl. Microbiol.
, 419.PubMedGoogle Scholar
Millett, M. A., Baker, A. J., and Satter, L. D. (1976), Biotechnol. Bioeng. Symp.
, 125.PubMedGoogle Scholar
Sidiras, D. K. and Koukios, E. G. (1989), Biomass
, 289–306.CrossRefGoogle Scholar
Furcht, P. W. and Siila, H. (1990), Biotechnol. Bioeng.
, 630–645.PubMedCrossRefGoogle Scholar
Ghose, T. K. (1969), Biotechnol Bioeng. 11
, 239–261.CrossRefGoogle Scholar
Neilson, M. J., Kelsey, R. G., and Shafizadeh, F. (1982), Biotechnol. Bioeng.
, 293–304.PubMedCrossRefGoogle Scholar
Jones, E. O. and Lee, J. M. (1988), Biotechnol. Bioeng.
, 34–40.CrossRefGoogle Scholar
Nakao, K., Funkunaga, K., Yasuda, Y., Tejima, Y., and Kimura, M. (1991), Kagaku Kogaku Ronbunshu
, 882–889.CrossRefGoogle Scholar
Sinitsyn, A. P., Gusakov, A. V., Davydkin, I. Y., Davydkin, V. Y., and Protas, O. V. (1993), Biotechnol. Lett.
, 283–288.CrossRefGoogle Scholar
Mackie, K. L., Brownell, H. H., West, K. L., and Saddler, J. N. (1985), J. Wood Chem. Technol.
, 405–425.CrossRefGoogle Scholar
Boussaid, A., Esteghlalian, A. R., Gregg, D. J., Lee, K. H., and Saddler. J. N. (2000), Appl. Biochem. Biotechnol.
, 693–705.PubMedCrossRefGoogle Scholar
Yang, B., Boussaid, A., Mansfield, S. D. and Saddler, J. N. (2002), Biotechnol. Bioeng.
in press.Google Scholar
Ghose, T. K. (1987), Pure Appl. Chem.
, 257–268.CrossRefGoogle Scholar
TAPPI, Technical Association of the Pulp and Paper Industry (1998), Standard Methods
, T-222 om-98, Atlanta, GA.Google Scholar
TAPPI, Technical Association of the Pulp and Paper Industry (1991), Useful Methods
, UM-250, Atlanta, GA, pp. 47,48.Google Scholar
Breuil, C., Chan, M., Gilbert, M., and Saddler, J. N. (1992), Bioresour. Technol.
, 139–142.CrossRefGoogle Scholar
Reese, E. Y. and Ryu, D. Y. (1980), Enzyme Microb. Technol.
, 239–240.CrossRefGoogle Scholar
Bader, J., Bellgardt, K., Singh, A., Kumar, P., and Shugerl, K. (1992), Bioprocess. Eng.
, 235–240.CrossRefGoogle Scholar
Medve, J., Karlsson, J., Lee, D., and Tjerneld, F. (1998), Biotechnol. Bioeng.
, 621–634.PubMedCrossRefGoogle Scholar
Ooshima, H., Kurakake, M., Kato, J., and Harano, Y. (1991), Appl. Biochem. Biotechnol.
, 253–266.PubMedCrossRefGoogle Scholar
Ooshima, H., Burns, D. S., and Converse, A. O. (1990), Biotechnol. Bioeng.
, 446–452.PubMedCrossRefGoogle Scholar
Lee, D., Yu, A. H. C., Wong, K. K. Y., and Saddler, J. N. (1994), Appl. Biochem. Biotechnol.
, 407–415.CrossRefGoogle Scholar
Converse, A. O., Ooshima, H., and Burns, D. S. (1990), Appl. Biochem. Biotechnol.
, 67–73.CrossRefGoogle Scholar
Cleresci, L. S., Sinitsyn, A. P., Saunders, A. M., and Bungay, H. R. (1985), Appl. Biochem. Biotechnol.
, 433–443.CrossRefGoogle Scholar
Yu, A. H. C, Lee, D., and Saddler, J. N. (1995), Biotechnol. Appl. Biochem.
, 203–216.Google Scholar
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