Antimicrobial activities of phenethyl isothiocyanate isolated from horseradish

Phenethyl isothiocyanate (PEITC) was obtained from horseradish. The preparation procedure was as follows: the horseradish powder was hydrolysed in the water first, and then, after filtration, the residue was extracted by petroleum ether; finally, PEITC was isolated by silica gel column. The structure of PEITC was identified by IR, MS, H-1-NMR and C-13-NMR chromatography methods. The inhibitory activities of PEITC against Gibberella zeae, Xanthomonas axonopodis pv. citri, Cytospora sp. and Phytophthora capsisi showed that PEITC had good inhibition effects. The EC50 values of G. zeae, X. axonopodis pv. citri, Cytospora sp. and P. capsisi were 13.92, 1.20, 0.73 and 3.69 mu g mL(-1), respectively.