Quality control of plant food supplements containing Citrus aurantium L. : a new HPLC method to measure active amines

Botanicals and botanical derivatives are widely used in Western diets from various sources; among them, plant food supplements (PFS) are the most usual commercialized forms. Citrus aurantium L. (bitter orange) is frequently used as an ingredient of food supplements aimed to reduce body weight or improve general physical performances. The most important compounds of C. aurantium are amines having adrenergic activity: octopamine, synephrine, tyramine, N-methyl-tyramine and hordenine. The C. aurantium extract is generally allowed in food supplements, but, in several countries, limits have been established, since some cases of adverse effects, involving mainly the cardiovascular system, have been reported in the scientific literature (1). With the decree dated July 09 2012, the Italian Ministry of Health established a limit of synephrine in C.aurantium-based products, in order to maintain the daily intake < 30 mg, whereas the sum of other amines, including octopamine, should be lower than 1/8 (12.5%) synephrine (2). On these bases, quality control of PFS is of crucial importance also taking into consideration that the illicit use of C. aurantium and/or its synthetic amines is not infrequent. The aim of this work was to set up and validate a new, quick and simple HPLC method using a fluorimetric detection; this method can be easily applied to the quality control of PFS containing C. aurantium, offering a new tool for industries involved in PFS production and laboratories responsible for the post-marketing control. 1. Haller, C.A., Benowitz, N.L. (2000). Adverse cardiovascular and central nervous system events associated with dietary supplements containing ephedra alkaloids. The New England Journal of Medicine, 343, 1833-1838. 2. Italian Ministry of Health (2002). Circolare n. 3. Applicazione della procedura di notifica di etichetta di cui all'art. 7 del decreto legislativo n. 111/1992, ai prodotti a base di piante e derivati aventi finalità salutistiche In Gazzetta Ufficiale n.188, 08.12.2002. The research leading to these results has received funding from the European Community’s Seventh Framework Program (FP7/2007-2013) under grant agreement n° 245199. It has been carried out within the PlantLIBRA project (website: www.plantlibra.eu). This report does not necessarily reflect the Commission's views or its future policy on this area.