Abstract
The production of nobiletin, sinensetin, quercetogetin, heptamethoxyflavone and tangeretin by Citrus aurantium (cv. Sevillano) fruits is described. The levels of these compounds were examined by high performance liquid chromatography-mass spectrometry. The results suggest that the highest levels of these polymethoxylated flavones were associated with young developing states in fruits and that they were located in the peel.