| 1-aminocyclopropane-1-carboxylic acid is the immediate precursor for ethylene, a phytohormone that is produced in many plant tissues, which is effective in trace amounts (≤ 1 microl/l). Quantitative determination of ACC in biological tissues is paramount to understanding the regulation of this metabolic process. The most widely accepted method for quantifying 1-aminocyclopropane-1-carboxylic acid requires its oxidation to ethylene, which then is measured by gas chromatography. Our objective was to develop a method for the rapid, direct quantification of 1-aminocyclopropane-1-carboxylic acid by using a gas chromatograph with a flame-ionization detector. Ethylene production was measured in tissues from fruits, leaves, seeds, florets, and flower petals. The remaining tissue samples were ground to a fine powder in liquid nitrogen, and 1-aminocyclopropane-1-carboxylic acid was extracted from the powder with a methanol:chloroform:water mixture (5:12:3 v/v/v). 1- aminocyclopropane-1-carboxylic acid was quantified by using an EZ:faast(TM) gas chromatography mass-spectrometry free amino acid analysis kit, was identified using gas chromatography mass-spectrometry, and was confirmed with authentic 1-aminocyclopropane-1-carboxylic acid. Additional benefits include a short run time of six minutes and the absence of a potentially hazardous tracer, such as 14C. We show that this method is effective for accurate, direct measurement of 1-aminocyclopropane-1-carboxylic acid from both reproductive and vegetative plant tissues. |
