Producing Epoxyethane as Food Fumigant Based on Biocatalysis

XU Ning;XIN Jiaying;WANG Yan;DOU Boxin;XIA Chungu;Key Laboratory for Food Science and Engineering,Harbin University of Commerce;College of Food Science,Northeast Agricultural University;State Key Laboratory for Oxo Synthesis and Selective Oxidation,Lanzhou Institute of Chemical Physics,Chinese Academy of Sciences;

food fumigant;;epoxyethane;;methanotrophic bacteria;;biocatalyst;;epoxidation

In addition to application in chemical manufacturing processes,epoxyethane is widely used in processes of food fumigating sterilization,particularly of grains and dried fruits. During the last decades,many research works have been focused on epoxidation reactions of ethylene by supported catalysts such as transition metal complexes and metal nanoparticles. In contrast with chemical synthetic methods,the biocatalytic reaction appears to be a mild and simple method. One biocatalytic method for producing epoxyethane is using methane monooxygenase( MMO) to insert oxygen across the carbon double bonds of ethylene. Epoxyethane synthesis by Methylosinus trichosporium IMV 3011 whole cells which contains the MMO has significant application potential as it is performed at normal temperature and pressure and causes no pollution. The process for producing epoxyethane was described. The effect of initial ethylene concentration on production of epoxyethane was studied. Initial concentrations of oxygen,ethylene and nitrogen were 50%,20% and 30%,respectively. The amount of epoxyethane formed by free biocatalyst was 29 μmol / mg in approximately 6 h. Moreover,the amount of epoxyethane formed by immobilized biocatalyst was 34 μmol / mg in approximately 8 h. In a batch reaction system, the regenerated immobilized biocatalyst can be repeatedly used for 8 times and 89% of initial MMO activity was retained,and the amount of epoxyethane formed was 3. 4 nmol.