| 摘要 |
PURPOSE:To obtain a poly-gamma-glutamate which has increased solubility in solvent and can give moldings such as fibers or films excellent in strengths, transpar ency, elasticity, etc., by esterifying the alpha-carboxyl groups of gamma-polyglutamic acid. CONSTITUTION:A polymer comprising repeating units (A) of formula I (wherein R is an ester-forming group, for example, a 1-30C, desirably 1-4C linear or branched substituted or unsubstituted hydrocarbon residue) and repeating units (B) of formula II and having a component A content of 40% or above and a degree of polymerization of at least 1000 is used as a poly-gamma-glutamate useful for the production of moldings such as fibers and films. This ester can be pro duced by esterifying poly-gamma-amino acid obtained by culturing gamma-polyglutamic acid-producing bacteria at 37 deg.C for 2-3 days in a nutrient medium comprising yeast extract, peptone, urea, K2HPO4 and amino acids. |
