title: Analysis of α-amylase inhibitor from corni fructus by coupling magnetic cross-linked enzyme aggregates of α-amylase with HPLC-MS.
abstract: As a carrier-free immobilization strategy, magnetic cross-linked enzyme aggregates (MCLEAs) showed improved enzyme activity, stability and magnetic response. In this study, MCLEAs of α-amylase (MCLEAs-amylase) was prepared under optimized conditions and characterized with scanning electron microscope and vibrating sample magnetometer. The prepared MCLEAs-amylase showed an amorphous structure and the saturation magnetization was 33.5emu/g, which was sufficient for magnetic separation. Then MCLEAs-amylase coupled with high performance liquid chromatography-mass spectrometry (HPLC-MS) was utilized to screen and identify α-amylase inhibitors from ethyl acetate extract of corni fructus. The experiment conditions were optimized. At the optimum conditions (incubation time: 10min, pH: 7.0 and temperature: 20°C), querciturone was successfully screened and identified with weak non-specific binding. The screening result was verified by inhibition assays and the IC50 value of querciturone was 22.5μg/mL. This method provided a rapid way to screen active compounds from natural products.
authors.affiliation: Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha 410205, China.
authors.forename: Liangliang
authors.initials: L
authors.lastname: Liu
authors.affiliation: School of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China.
authors.forename: Yin
authors.initials: Y
authors.lastname: Cen
authors.affiliation: School of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China.
authors.forename: Fang
authors.initials: F
authors.lastname: Liu
authors.affiliation: School of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China.
authors.forename: Jingang
authors.initials: J
authors.lastname: Yu
authors.affiliation: School of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China.
authors.forename: Xinyu
authors.initials: X
authors.lastname: Jiang
authors.affiliation: School of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China. Electronic address: xqchen@csu.edu.cn.
authors.forename: Xiaoqing
authors.initials: X
authors.lastname: Chen
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods; D029768:Cornus / Q000737:chemistry*; D004791:Enzyme Inhibitors / Q000032:analysis* / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D004800:Enzymes, Immobilized / Q000737:chemistry* / Q000378:metabolism; D017743:Equipment Reuse; D058185:Magnetite Nanoparticles / Q000737:chemistry; D013058:Mass Spectrometry / Q000379:methods; D010936:Plant Extracts / Q000737:chemistry*; D000516:alpha-Amylases / Q000737:chemistry* / Q000378:metabolism
chemical_list: D004791:Enzyme Inhibitors; D004800:Enzymes, Immobilized; D058185:Magnetite Nanoparticles; D010936:Plant Extracts; D000516:alpha-Amylases
keywords: Corni fructus; Cross-linked enzyme aggregates; HPLC–MS; Magnetic; α-Amylase