用固定化L-赖氨酸脱羧酶细胞制备1,5-戊二胺

研究了4种固定化蜂房哈夫尼菌(H.alveiAS1.1009)菌体细胞的材料和方法,包括海藻酸钙包埋法、半透膜透析袋法、海藻酸钙-明胶交联包埋法和明胶包埋法。其中海藻酸钙包埋法稳定性最好,该方法最优转化条件为:在ρ(海藻酸钠)=30g/L的水溶液中,最适菌体质量浓度为ρ(菌体)=30.8g/L,100mL转化液中海藻酸钙球体体积为30mL,转化最适温度为37℃,最适pH=5.0。用该方法转化测得比酶活可达1028.9U。重复性佳:第一批固定化细胞酶活可达游离菌体的98.62%,第四批可达第一批酶活的38.68%。

Producing Cadaverine by Cell Immobilization of Lysine Decarboxylase

Four materials and methods of H.alvei cell immobilization procedures,including Ca-alginate embedded,dialysis bag,Ca-alginate-gelatin embedded and gelatin embedded,were studied.Ca-alginate as carrier are much more stable than any other materials.The optimum conditions of immobilization were:cell loading ratio 30.8 g cell/L gelatin,ρ(sodium alginate)=30 g/L,30 mL gelatin sphere in 100 mL transforming liquid,transforming temperature 37 ℃ and pH 5.0.The enzyme activity can reach 1 028.9 U.The immobilization procedure with Ca-alginate as carrier can attain 98.62% of the enzyme activity of the free bacterium cells in the first time,and in the forth time it is 38.68% as the first time.