摘要
以Fe3O4和壳聚糖为原料,以戊二醛为交联剂制备磁性壳聚糖微球,固定化碱性蛋白酶,并对其品貌及结构性质进行观察和分析。结果表明:壳聚糖微球具有良好的球形外貌,大小约为15nm,固定化后粒子大小约为20nm;红外光谱分析证实Fe3O4已被壳聚糖包裹;固定化酶前后粒子晶形完整,均具有良好的磁响应能力和超顺磁性。固定化酶与游离酶相比,最适温度从60℃下降到50℃;最适pH值从10升至11;固定化酶的Km为5.85×10-4mg/mL,游离酶的Km为6.06×10-4mg/mL。
Alkaline protease was immobilized onto magnetic chitosan microspheres prepared from Fe3O4 and chitosan by crosslinking with glutaraldehyde and its appearance and structural properties were analyzed.The results showed that the magnetic chitosan microspheres had spherical appearance with a particle size increasing from 15 to 20 nm after immobilization.FT-IR analysis revealed that Fe3O4 was well wrapped up in the magnetic chitosan microspheres.The magnetic chitosan microspheres had complete crystal structure,good magnetic response and strong superparamagnetic behaviors before and after immobilization of alkaline protease.The optimal reaction temperature and pH for the immobilized enzyme were 50 ℃ and 11 compared with 60 ℃ and 10,respectively,for the free enzyme.The Km was 5.85 ×10-4 mg/mL for the immobilized enzyme and 6.06 ×10-4 mg/mL for its free counterpart.
出处
《食品科学》
EI
CAS
CSCD
北大核心
2012年第21期249-252,共4页
Food Science
基金
黑龙江省科技攻关计划项目(GA09B401-6)
国家现代农业产业技术体系建设专项(nycytx-004)
关键词
壳聚糖
磁性
固定
碱性蛋白酶
酶学性质
magnetism
chitosan
immobilization
alkaline protease
enzymatic property
