Abstract
Lipid peroxide-derived carbonyls (aldehydes and ketones) are reactive species. Like reactive oxygen species, they work as signal molecules at low concentrations and damage various cellular components at high concentrations. In order to elucidate the regulation and physiological effects of carbonyls in leaves, we here established a comprehensive analysis of carbonyls. Leaves of Arabidopsis thaliana were extracted with acetonitrile. The extract was derivatized with 2,4-dinitrophenylhydrazine, and separated on a reversed-phase HPLC column. More than 50 species of carbonyls were detected, among which aldehydes and ketones of carbon chain length 3-10 with or without C=C double bond, were identified by comparison of their retention time with standard compounds. Three ecotypes Col-0, Nos, and Ler, showed similar profiles of carbonyls except that Col-0 showed lower 3Z-hexenal and 2E-hexenal levels, corresponding well with the lack of hydroperoxide lyase (HPL) activity in Col-0. This result imply the HPL-independent production of aldehydes in leaves.
