High-performance liquid chromatography electrospray mass spectrometry in phytochemical analysis of sour orange (Citrus aurantium L.)

High-performance liquid chromatography coupled with a UV photodiode-array detector and an electrospray mass spectrometer (HPLC-ES-MS) was used to analyze the phytochemical constituents of an extract of sour orange (Citrus aurantium L., family Rutaceae). Eight flavonoids were identified, as isonaringin (1), naringin (3), hesperidin (5), neohesperidin (6), naringenin (2), hesperitin (4), nobiletin (8) and tangeritin (7). The permethoxylated flavones tangeritin (7) and nobiletin (8) showed the most intense protonated molecules. This method can be used to detect trace amounts of these compounds in an orange extract. (C) 1997 Elsevier Science B.V.