Application of Biochar to Enzyme Carrier for Stress Tolerance of Enzymes

Biochar showed the high affinity to enzymes, and enzymes were sufficiently adsorbed on the surface of biochar. Enzymes were highly stabilized in water at high temperatures by adsorbing enzymes on biochar. The remaining activity of lysozyme adsorbed on adzuki bean charcoal showed around 50% after heat treatment at 90°C for 30 min though that of free lysozyme was almost lost. Likewise, the stability of enzymes was enhanced in organic solvents by adsorbing enzymes on biochar. The conformation of α -chymotrypsin adsorbed on bamboo charcoal was hardly influenced by organic solvents, while that of free α -chymotrypsin was strongly dependent of the kind of organic solvents. Moreover, the adsorption of α -chymotrypsin on bamboo charcoal improved the transesterification of N -acetyl-L-tyrosine ethyl ester with n -butanol in organic solvents. The transesterification rate of α -chymotrypsin adsorbed on bamboo charcoal was about 760 times higher than that of free α -chymotrypsin in n -butyl acetate.