title: A novel method for the synthesis of glyceryl monocaffeate by the enzymatic transesterification and kinetic analysis.
abstract: A novel enzymatic method for glyceryl monocaffeate (GMC) preparation by the transesterification of ethyl caffeate (EC) was investigated. The effects of reaction variables (reaction pressure, temperature, reaction time, enzyme load, and substrate ratio) on the enzymatic transesterification were studied and optimized using response surface methodology. HPLC-ESI-MS and HPLC-UV were used to monitor the transesterification. Thermodynamics, kinetic analyses and reaction mechanism were also evaluated. Results showed that, GMC can be successfully prepared by the enzymatic transesterification of EC with glycerol. Under the optimal conditions (enzyme load 22.54%, EC:glycerol=1:12.75 (mol/mol), 72.5°C, and 10.5h), EC conversion and GMC yield were 97.9±0.7% and 95.8±1.0%, respectively. The activation energies (Ea) for EC conversion and GMC formation were 44.23 and 46.51kJ/mol, respectively. The kinetic values for Vmax, Km(') and KIA were 2.18×10(-3)mol/(Lmin), 0.086mol/L, and 0.52mol/L, respectively. The transesterification mechanism with EC inhibition was also proposed.
authors: Lipid Technology and Engineering, School of Food Science and Engineering, Henan University of Technology, Lianhua Road 100, Zhengzhou 450001, Henan Province, PR China. Electronic address: sunshangde@hotmail.com.
authors: Shangde
authors: S
authors: Sun
authors: Lipid Technology and Engineering, School of Food Science and Engineering, Henan University of Technology, Lianhua Road 100, Zhengzhou 450001, Henan Province, PR China. Electronic address: 15136172867@126.com.
authors: Bingxue
authors: B
authors: Hu
mesh_terms: D002109:Caffeic Acids / Q000378:metabolism*; D004950:Esterases; D004951:Esterification; D005990:Glycerol; D007700:Kinetics; D008049:Lipase / Q000378:metabolism; D013696:Temperature
chemical_list: D002109:Caffeic Acids; C032773:ethyl caffeate; D004950:Esterases; D008049:Lipase; D005990:Glycerol
keywords: Caffeic acid; Glyceryl monocaffeate; HPLC-ESI-MS; Novozym 435; Response surface methodology; Thermodynamic analysis; Transesterification mechanism