聚氨酯泡沫固定产脂肪酶粗状假丝酵母（Candidav alida T2）细胞的研究

对聚氨酯泡沫固定产脂肪酶粗状假丝酵母（Candida validaT2）细胞的固定化条件进行了研究。实验结果表明，聚氨酯泡沫颗粒经密度和粒径筛选，酸碱处理，以及固液比优化，载体固定细胞干质量比达到157lmg／g，细胞脂肪酶的酶活为每克干细胞1415U。电镜图片显示粗状假丝酵母菌（Candida validaT2）在载体孔隙内和脊壁上缠绕充盈，生长良好，固定结构稳定。固定化细胞连续催化水解桐籽油5批次，细胞相对水解酶活保持率达73％，固定细胞的损失率为12．5％。固定化细胞颗粒显示出良好的操作稳定性和酶活保持率，为进一步的应用研究提供了实验基础。

Immobilization of lipase-producing cells of Candida valida T2 with polyurethane foams

The immobilization conditions of lipase-producing cells of Candida valida T2 with polyurethane foam were investigated. The results showed that the cell load of polyurethane foam reached 1 415 mg/g and the lipase activity of the dry cell achieved 1 255 U/g after the optimization of the conditions on the carrier density, the particle size, the pretreatment procedure, and the ratio of solid carrier to fermentation broth. Scanning electric microscope showed the mycelium Candida valida T2 enlaced or filled in the rib and on the inner wall of the carrier cavity. The immobilized Candida valida T2 cells grew well and colony configuration was stable. In a catalyzed hydrolysis of tung oil by the immobilized cells, the enzymatic activity remained 73%, and the each rate was 12. 5% after five repeat reactions.