Submitted to: Analytical Methods
Publication Type: Peer reviewed journal
Publication Acceptance Date: 11/14/2009
Publication Date: 1/5/2010
Citation: Fiore, M., Rimando, A.M., Andolfi, A., Evidente, A. 2010. A New GC-MS Method for the Analysis of Ascaulitoxin, Its Aglycone and 4-Aminoproline from Culture Filtrates of Ascochyta caulina. Analytical Methods. 2:159-163. Interpretive Summary: A new method was developed for the analysis of ascaulitoxin (1), ascaulitoxin aglycone (2), and 4-amino-D-proline (3), which are compounds with potential herbicidal activity produced by the fungus Ascochyta caulina. The method, which involved treating the lyophilized culture filtrate with a derivatizing reagent, and analyzing the derivatized compounds by gas chromatography-mass spectrometry, was rapid, sensitive, and specific. Using this new method of analysis, it is suggested that phytotoxicity is correlated with the amount of ascaulitoxin in the culture filtrates. A new method for the purification of compound 2 is also described.
Technical Abstract: A new GC-MS method was developed for the analysis of ascaulitoxin, its aglycone, and 4-amino-D-proline, which are phytotoxins with potential herbicidal activity produced by Ascochyta caulina. The method involved directly treating the lyophilized culture filtrate with a derivatizing reagent, converting the mixture of toxins in the filtrate to their corresponding trimethylsilyl derivatives, and consequent analysis by EI-MS. The method is rapid, sensitive and highly specific for the identification and analysis of the toxins in a complex sample matrix. Analysis of culture filtrates using this method suggested that phytotoxicity correlates with the level of ascaulitoxin in the culture filtrate. A new method for the purification of 2,4,7-triamino-5-hydroxyoctandioic acid, the aglycone of ascaulitoxin, is also described.