| 摘要 |
PURPOSE:To obtain a novel copolymer having bio-degradability and bio- compatibility at a low cost by culturing a polyhydroxyalkanoate-producing strain in the presence of delta-valerolactone, 1,5-pentanediol and their esters under specific condition. CONSTITUTION:A microbial strain capable of producing polyhydroxyalkanoate (e. g. Alcaligenes eutrophus ATCC 17699) is cultured under restricted supply of nitrogen and/or phosphorus in the presence of delta-valerolactone, 1,5-pentanediol and/or mono- or dicarboxylic acid ester of 1,5-pentanediol to obtain the objective copolymer having a weight-average molecular weight of 10,000-2, 500,000 and composed of 70-90mol% of 3-hydroxybutyrate unit of formula I, 1-20mol% of 3-hydroxyvalerate unit of formula II, 1-15mol% of 3-hydroxypropionate unit of formula III and 1-10mol% of 5-hydroxyvalerate unit of formula IV as the recurring units. |
