Enhancement of Lytic Activity of HEWL Adsorbed on Biochar by the Optimization of Adsorption Conditions

We have found that HEWL (hen egg white lysozyme) is effectively immobilized on biochar through adsorption, and the amount of HEWL adsorbed on biochar is strongly dependent on the pH value of adsorption solutions. The structure of HEWL adsorbed on biochar changed by the pH value of adsorption solutions and became similar to that of native HEWL at acidic pH value, although the structure of HEWL solubilized in the solution was the same in the range between pH 4 and 9. On the other hand, the lytic activity of biochar-adsorbed HEWL toward Micrococcus lysodeikticus was markedly influenced by the pH value of adsorption solutions and increased with decreasing the pH value. Moreover, the addition of KCl to adsorption solutions enhanced the lytic activity of biochar-adsorbed HEWL.