Determination of para-synephrine and meta-synephrine positional isomers in bitter orange-containing dietary supplements by LC/UV and LC/MS/MS

Distribution of C- and O-glycosyl flavonoids, (3-hydroxy-3-methylglutaryl)glycosyl flavanones and furocoumarins in Citrus aurantium L. juice

“…However, the growing interest in sour orange products is due to the fact that they are rich in different classes of bioactive compounds such as synephrine alkaloids (Santana, Sharpless, & Nelson, 2008), which showed controversial effects on blood pressure and heart rate, limonoids and phytosterols (Jayaprakasha, Jadegoud, Gowda, & Patil, 2010) and flavonoids Bellocco et al, 2009), which are associated with anticancer activity and apoptotic activation. As for the latter, previous studies (Kawaii, Tomono, Katase, Ogawa, & Yano, 1999;Nogata et al, 2006) reported the chromatographic separation of the main flavonoid components of C. aurantium.…”

Development and validation of a GC/IT-MS method for simultaneous quantitation of para and meta-synephrine in biological samples

“…[3,9,36]. Furthermore, UV detection presents several interferences, since dietary supplements and vegetable biological samples are very complex matrices.…”

“…1) with nonequivalent pharmacological properties. o-Synephrine is not used as a pharmaceutical agent and its presence in nature has not been documented [3]. Furthermore, it is well Abbreviations:…”

Analysis of octopamine in human doping control samples

“…Due to its stimulating properties, octopamine has been prohibited in elite sports by the World Anti-Doping Agency (WADA) as a specified substance (World Anti-Doping Agency, 2010), and several adverse analytical findings (AAFs) of octopamine in doping control samples have been reported during recent years (World Anti-Doping Agency, 2011). The fact that synephrine and octopamine are present as major and minor components, respectively, in natural products (Table 1) derived, for example, from bitter orange (Citrus aurantium; Fugh-Berman and Myers, 2004;Kusu et al, 1996;Nelson et al, 2007;Penzak et al, 2001;Putzbach et al, 2007;Santana et al, 2008), as well as the assumption that synephrine might be converted in vivo into octopamine, necessitated administration studies with nutritional supplements containing one or the other ingredient in defined amounts. These studies were further required to compare to urine samples collected and analyzed after application of synephrine-or octopamine-containing therapeutics.…”