固定化Methylomonas Z201细胞：甲烷单加氧酶的活性和稳定性

分别以海藻酸钙和砂子为载体，采用包埋和吸附技术固定化ＭｅｔｈｙｌｏｍｏｎａｓＺ２０１细胞．以丙烯环氧化为指标反应，系统研究固定化对ＭｅｔｈｙｌｏｍｏｎａｓＺ２０１细胞ＭＭＯ活性和稳定性的影响．结果表明，对包埋细胞，合适的负载量和粒径为保留较高ＭＭＯ活性所必需．砂子对细胞的吸附能力中等．外源性电子给体甲酸钠对游离和固定化细胞的ＭＭＯ活性影响不同．固定化细胞的最适ｐＨ值和温度与游离细胞相同，但活化能降低．固定化细胞保留游离细胞ＭＭＯ活性的６０—７０％，操作稳定性、热稳定性、贮存稳定性均有所提高．

Immobilized Methylomonas Z201 Cells:MMO Activity and Stability

Methylomonas Z201 cells entrapped in alginate and adsorbed on sand were used as biocatalysts to catalyze the epoxidation of propene. Effects of cell load and particle diameter for entrapped cells, amount of adsorption on sand and exogeneous electron donor sodium formate on MMO activity were studied. Results showed that combination of suitable cells load and smaller particle diameter give higher MMO activity. Cells had medium adsorption ability on sand. Different effects of sodium formate on MMO activity of free and immobilized cells were observed. The optimum PH and temlierature remained the same between free and immobilized cells and activation energy was declined. Immobilized cells retained 60 70% MMO activity of free cells and enhanced operational stability, thermal stability and storage stabllity of cells.