摘要
采用反相悬浮法与溶胶凝胶法结合制备磁性壳聚糖微球,并以此为载体,京尼平为交联剂,脂肪酶为模型酶进行固定化,研究了酶固定化的最优条件和固定化酶的性质。结果表明,在京尼平浓度为0.6 g/L、交联温度为55℃、交联时间8 h,固定化酶的比活力最大,为4.31 U/g。固定化酶在25～35℃,pH值在8.0有最大活性,其米氏常数Km为0.26 mol/L。同时,固定化酶具有良好的热稳定性及pH稳定性,可重复利用,且能进行磁分离。
Inverse suspension combined with the sol-gel method was deployed to prepare a magnetic chitosan microspheres. The lipase was immobilized on magnetic chitosan microspheres with genipin as the cross-linking reagent. The optimum conditions and properties of immobilization enzyme were investigated. The maximal specific activity of 4.31 U/g was achieved when the crosslinking reaction was carried out at 55 ℃ for 8 h using 0.6 g/L genipin. The optimum pH, temperature and Km of the immobilized enzyme were 8, 25~35 ℃ and 0.26 mol/L, respectively. The immobilized lipase showed improved thermal stability and remained active in a broader pH range, compared with those of free lipase. Such immobilized lipase can be recycled via the magnetic separation for a certain extent.
出处
《应用化学》
CAS
CSCD
北大核心
2013年第8期922-926,共5页
Chinese Journal of Applied Chemistry
基金
国家"863"课题(2010AA023001)
国家自然科学基金(20927005
21275049
81274178)
湖南省科技计划课题(2010TT1001)
湖南省高校科技创新团队支持计划资助
关键词
磁性壳聚糖微球
京尼平
固定化酶
magnetic chitosan microspheres
genipin
immobilized enzyme
