GC/MS analysis of the volatiles produced by the action of endogenous myrosinase in Cleome chrysantha Decne. herb, showed three major components, 1-isocyano-4-methyl benzene, gamma-muurolene and (cis) nerolidole (21.72%, 12.15% and 10.39%, respectively). 1-isocyano-4-methyl benzene is not produced