利用甲壳素固定大肠杆菌(E.coli)细胞转化苯丙酮酸形成L-苯丙氨酸的研究

Production of L-Phenylalanine by Immobilized E. coli Cells on Chitin

利用甲壳素作为固定化介质,能够保留83.3％的游离细胞转氨酶活性,以0.35mol/L苯丙酮酸为前体,于37℃下反应9小时,可产L-苯丙氨酸54.3g/L,其克分子转化率为94％。同时,用25％戊二醛溶液(30μl/g·cell)处理细胞1小时,再用0.3％OP溶液浸泡处理15小时,可以使固定化细胞转化率有较大的提高,Mg^(2+)对转化也有促进作用。

Using immobilized Escherichia coli cells on chitin with 83.3% transaminase activity as to free cells, L-phenylalanine could be produced from phenylpyruvic acid and L-Aspartic acid rapidly and efficiently. L-phenylalaine could be obtained 54.3g/L in 9 hours of incubation; the molar yield was 94%. Using immobilized cells treated with 25% glutaraldehyde solution (30μL/g · cell) for 1 hour, and soaked in 0.3% OP solution for 15 hours, higher conversion rate to phenylpyruvic acid could be achieved.