<Original>Enzymatic Saccharification of Woody Plants : I. Effects of Expanded Softening and Ball-milling on Enzymatic Saccharification

Abstract

Domestic hard wood mixtures were subjected to expanded softening (160-190℃, 6-15 kg/cm^2) followed by enzymatic saccharification. No substantial differences were observed in the chemical composition and degree of crystallinity, except for that of pentosan. Xylan portion is decomposed during expanded softening. Expanded softening did not enhance the accessibility of enzymes to substrates in contrast to the case of ball-milling, but appeared to inhibit saccharification. No enzyme preparations commercially available could digest more than 20%. Present results suggest that the condition of expanded softening is too mild to decompose lignin and that more drastic condition is necessary to achieve sufficient amount of saccharification.