Liquid chromatography for separation and quantitative determination of adrenergic amines and flavonoids from Poncirus trifoliatus Raf.: Fruits at different stages of growth

The fruits of Poncirus trifoliatus Raf. (Rutaceae) have been used against allergic diseases for generations and still occupy an important place in traditional oriental medicine. They have also been used to treat gastric and duodenal ulcers. Chemical analysis of extracts of Poncirus trifoliatus Raf. fruit at different stages of maturation revealed variations in the concentrations of flavonoids present. Fourteen flavonoids (neoeriocitrin, norirutin, naringin, hesperidin, neohesperidin, neoponcirin, poncirin, naringenin, hesperetin, sinensetin, nobiletin, heptameth-oxyllavone, 5-O-demethylnobiletin, and tangeretin) and five amines (synephrine, octopamine, N-methyltyromine, hordenine, and tyramine) in extracts from the fruit of Poncirus trifoliatus Raf. were analyzed by HPLC with a C-18 reversed-phase column. The concentrations of the four flavonoids naringin, poncirin, narirutin, and neoponcirin was maximum during the first stage of growth and gradually decreased until the fruits were fully developed. The paper also discusses the anatomical variations observed at different stages of development of the fruit.