Abstract
A two-stage dilute-acid percolation (DA) was investigated as a pretreatment method for switchgrass. With use of extremely low acid (0.078 wt% sulfuric acid) under moderate temperature (145–170°C), hemicellulose in switchgrass was completely solubilized showing no sugar decomposition. The treated switchgrass contained about 70% glucan and 30% lignin. The high lignin content in the treated feedstock raises a concern that it may cause a high enzyme consumption because of irreversible adsorption of cellulase enzymes to lignin. This problem may be amplified in the SSF operation since it is usually run in fed-batch mode and the residual lignin is accumulated. The DA pretreatment was, therefore, combined with the ammonia recycled percolation (ARP) process that has been proven to be effective in delignification. The combined pretreatment essentially fractionated the switchgrass into three major components. The treated feedstock contained about 90% glucan and 10% lignin. The digestibility of these samples was consistently higher that that of DA treated samples. Further study on the interaction of cellulase with xylan and that with lignin has shown that the enzymatic hydrolysis of cellulose is inhibited by lignin as well as xylan. The external xylan was found to be a noncompetitive inhibitor to cellulose hydrolysis. The cellulase used in this study was proven to have the xylanase activity.
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References
Chernaglazov, V. M., Ermolova, O. V., and Klyosv, A. A. (1988),Enzyme Microb. Technol. 10, 503–507.
Tanka, M., Fukui, M., and Mastsuno, R. (1988),Biotechnol. Bioeng. 32, 897–902.
Lee, D., Yu, A. H. C., and Saddler, J. N. (1995),Biotechnol. Bioeng. 45, 328–336.
Castellanos, O. F., Sinitsyn, A. P., and Vlasenko, E. Y. (1995),Bioresouce Technol. 52, 109–117.
Giard, D. J. and Converse, A. O. (1993),Appl. Biochem. Biotechnol. 39/40, 521–533.
Ooshima, H., Burns, D. S., and Converse, A. O. (1990),Biotechnol. Bioeng. 36, 446–452.
Ngugen, Q. A., and Saddler, J. N. (1991),Bioresearch and Technol. 35, 275–282.
Stone, J., Scallan, A., Donefer, E., and Ahlgren, E. (1969),Adv. Chem. Seri. 95, 219–241.
Ramos, L. P., Breuil, C., and Saddler, J. N. (1992),Appl. Biochem. Biotechnol. 34/35, 37–48.
Yoon, H. H., Wu, Z. W., Kim, S. B., and Lee, Y. Y. (1995),Appl. Biochem. Biotechnol. 51/52, 5–19.
Iyer, P., Wu, Z. W., and Lee, Y. Y. (1996),Appl. Biochem. Biotechnol. 57/58, 121–132.
Lee, Y. Y., Lin, C. M., and Chambers, R. P. (1979),Biotechnol. Bioeng. Symp. 8, 75–88.
Torget, R., Walter, P., Himmel, M., and Grohmann, K. (1991),Appl. Biochem. Biotechnol. 28/29, 75–86.
Chen, R., Torget, R., and Lee, Y. Y. (1996),Appl. Biochem. Biotechnol. 57/58, 133–146.
Torget, R., Hatzis, C., Hayward, T. K., Hsu, T., and Philippidis, G. P. (1996)Appl. Biochem. Biotechnol. 57/58, (in press).
Sjöström, E. (1993),Wood Chemistry: Fundamentals and Applications, 2nd edition, Academic Press, New York, NY.
Grohmann, K., Mitchell, D. J., Himmel, M. E., Dale, B. E., and Schroeder, H. A. (1989),Appl. Biochem. Biotechnol 20/21, 45–61.
Kong, F., Engler, C. R., and Soltes, E. J. (1992),Appl. Biochem. Biotechnol. 34/35, 23–35.
Wilson, D. B. (1992),Critical Review in Biotechnology,12(1/2), 45–63.
Matsushita, O., Russell, J. B., and Wilson, D. B. (1990),J. Bacteriol,17, 3620–3630.
Yagüe, E., Béguin, P., and Aubert, J.-P. (1990),Gene 89, 61–67.
Johnston, D. B. and Sheomaker, S. P. (1996), Assessment of Enzyme Kinetics Using Purified Endoglucanases and Insoluble Substrates, presented at 18th Symposium of Biotechnology for Chemicals and Fuel, Gatlinburg, TN.
Kim, B. J., Lee, Y. Y., and Torget, R. (1994),Appl. Biochem. Biotechnol. 45/46, 113–129.
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Wu, Z., Lee, Y.Y. Ammonia recycled percolation as a complementary pretreatment to the dilute-acid process. Appl Biochem Biotechnol 63, 21–34 (1997). https://doi.org/10.1007/BF02920409
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DOI: https://doi.org/10.1007/BF02920409