| 摘要 |
PURPOSE:To collect a converted L-amino acid in high yield, by treating an L- acyl-DL-amino acid with acylase produced by a fungus belonging to the genus Cryptococcus. CONSTITUTION:A fungus capable of producing acylase, belonging to the genus Cryptococcus, Candida, Trichosporon, is cultivated in a liquid medium. This cultivation is usually carried out by aerated spinner culture at 30-35 deg.C at 6- 8pH. The culture is directly used as an enzyme source, or a culture such as a cell-free extracted solution obtained by grinding the separated mold or mold, or separated acylase is used as the enzyme source. Namely, this acylase is made to act on an N-acyl-DL-amino acid at 30-35 deg.C at 6.0-7.0pH, it is asymmetrically hydrolyzed, to give an L-amino acid (e.g., L-methionine). In the asymmetric hydrolysis, the presence of a metal ion such as Co ion in the reaction solution promotes the reaction, and the reaction can be completed in 3-20hr. |
