« Previous AbstractThe use of the lactone motif in chemical communication    Next AbstractVolatile organic compound and particulate matter emissions from an ultrasonic essential oil diffuser »

Anal Biochem

Title:		Profiling of structurally labile oxylipins in plants by in situ derivatization with pentafluorobenzyl hydroxylamine
Author(s):		Schulze B; Lauchli R; Sonwa MM; Schmidt A; Boland W;
Address:		"Max Plank Institute for Chemical Ecology, 07745 Jena, Germany"
Journal Title:		Anal Biochem
Year:		2006
Volume:		20051115
Issue:		2
Page Number:		269 - 283
DOI:		10.1016/j.ab.2005.10.021
ISSN/ISBN:		0003-2697 (Print) 0003-2697 (Linking)
Abstract:		"A GC-MS-based method for the simultaneous quantification of common oxylipins along with labile and highly reactive compounds based on in situ derivatization with pentafluorobenzyl hydroxylamine to the corresponding O-2,3,4,5,6-pentafluorobenzyl oximes (PFB oximes) is presented. The approach covers oxo derivatives such as jasmonic acid (JA), 12-oxophytodienoic acid (OPDA), certain phytoprostanes, unsaturated oxo-acids, oxo-hydroxy acids, and aldehyde fragments from the polar head of fatty acids. In the positive electron impact-MS mode, the PFB oximes display characteristic fragment ions that greatly facilitate the identification of oxylipins in complex matrices. In addition, the fluorinated derivatives allow a highly selective and low-background analysis by negative chemical ionization. Besides showing the general value of the method for the identification of a broad range of oxylipins (18 examples), we also demonstrate sensitivity, linearity, and reproducibility for the quantification of JA, OPDA, 11-oxo-9-undecenoic acid, and 13-oxo-9,11-tridecadienoic acid. The efficiency of the method is demonstrated by differential profiling of these four oxylipins in lima bean leaves after mechanical wounding and feeding by the herbivore Spodoptera littoralis. Caterpillar feeding induced several oxylipins, whereas after wounding only the level of JA increased. The rapid in situ derivatization prevents the isomerization of cis-JA to trans-JA. The resting level of JA in lima beans showed an isomer ratio of 80:20 for trans/cis-JA. After wounding, de novo synthesis of JA alters the ratio to 20:80 in favor of the cis isomer"
Keywords:		"Animals Cyclopentanes/analysis Fatty Acids, Monounsaturated/analysis Fatty Acids, Unsaturated/*analysis Gas Chromatography-Mass Spectrometry/*methods Hydroxylamines/*chemistry Oximes/*analysis Oxylipins Phaseolus/chemistry Plant Leaves/chemistry Plants/*c;"
Notes:		"MedlineSchulze, Birgit Lauchli, Ryan Sonwa, Mesmin Mekem Schmidt, Annika Boland, Wilhelm eng Research Support, Non-U.S. Gov't 2005/11/26 Anal Biochem. 2006 Jan 15; 348(2):269-83. doi: 10.1016/j.ab.2005.10.021. Epub 2005 Nov 15"