摘要
利用反相悬浮交联法制备壳聚糖微球,然后采用化学共转化法制备了磁性壳聚糖微球(magnetic chitosan microspheres,M-CS),并对胃蛋白酶进行固定化研究。结果表明,制备的M-CS呈规则圆球形,有很好的磁响应性,并且在弱酸弱碱环境下能稳定保存。磁性壳聚糖微球对胃蛋白酶的吸附性实验表明,磁性壳聚糖微球能吸附胃蛋白酶,可是吸附胃蛋白酶的量受到载体与酶比例、溶液的离子浓度、溶液的pH值影响很大。胃蛋白酶动力学性质研究表明,相对于游离的胃蛋白酶,固定化后的酶的最适温度有所升高,最适温度在60℃、酸碱稳定性略有改善,最适pH4.0,故固定化后的酶的热稳定性和酸碱稳定性都得到明显改善。
In this experiment, chitosan microspheres were prepared by reversephase suspension cross-linkage method and then magnetic chitosan microspheres (M-CS) were prepared by chemical cotransfortion to immobilize pepsin. Under scan microscope, the M-CS show regular spheroid. They have magnetic response, and are stable in weak basic and weak acid solutions.The experimental results on adsorption of M-CS to pepsin showed that pepsin can be adsorbed by the M-CS, but the adsorption quantity is greatly influenced by ratio of the carrier to pepsin and ion strength and pH of buffer solution.The optimum temperature and pH of immobilized pepsin are 60 ℃ and 4.0 respectively. The immobilization improves thermal and pH stabilities of free pepsin.
出处
《食品科学》
EI
CAS
CSCD
北大核心
2008年第11期316-323,共8页
Food Science
基金
湖南省科技厅重点项目(06FJ4051)
关键词
磁性壳聚糖微球
胃蛋白酶
固定化
magnetic chitosan microspheres
pepsin
immbbilization