Simultaneous Determination of Quinolizidine Alkaloid and Biphenylquinolizidine Lactones from Heimia salicifolia by HPLC-UV and LC-MS Methods

Heimia salicifolia Link & Otto (Lythraceae) is a wild flowering shrub distributed from Mexico, southwestern Texas to northern Argentina. In Central and South America it has been used as antipyretic, emetic, laxative, diuretic, anti-inflammatory and for its wound healing activity. The folkloric reports claimed that the plant had psychotomimetic activity [1]. Biphenylquinolizidine lactones in Heimia salicifolia are a group of quinolizidine alkaloids having O-substituents at C-22 and C-23 positions of the biphenyl nucleus, and forming a lactone bridge between C-2 and C-4.

Both HPLC-UV and LC-MS methods were developed for the quantitative and qualitative determination of quinolizidine alkaloid and biphenylquinolizidine lactones including (2S,4S,10R)-4-(3-hydroxy-4-methoxyphenyl)-quinolizidin-2-acetate (1), heimidine (2), dehydrodecodine (3), lyfoline (4), 9b-hydroxyvertine (5), epi-lyfoline (6), lythrine (7) and vertine (8) from H. salicifolia. The separation of seven biphenylquinolizidine lactones and one quinolizidine alkaloid was achieved by using C-18 column material in HPLC method coupled with a PDA detector, a mixture of water and acetonitrile, both containing 0.1% acetic acid, has been selected as the mobile phase. The column temperature was maintained at 25°C. The method was validated for linearity, repeatability, limits of detection (LOD) and limits of quantification (LOQ). The structures of biphenylquinolizidine lactones and quinolizidine alkaloid were further characterized by LC-MS method according to the previous MS/MS study of quinolizidine alkaloids in H. salicifolia [2]. The developed HPLC-UV and LC-MS methods will be useful for the determination of quinolizidine alkaloid and biphenylquinolizidine lactones in H. salicifolia, and its related biological studies and forensic science.

Fig.1: HPLC-UV Chromatograms of standards (A) and extracts of H. salicifolia. (B) at 230nm

Acknowledgements: This research is supported in part by „Science Based Authentication of Dietary Supplements“ and „Botanical Dietary Supplement Research“ funded by the Food and Drug Administration grant numbers 5U01FD002071–09 and 1U01FD003871–01, and the United States Department of Agriculture, Agricultural Research Service, Specific Cooperative Agreement No. 58–6408–2-0009. References: [1] Malone MH, et al. (1994)J Ethnopharm 42: 135–159. [2] Wang YH, et al. (2009) Planta Med 75(4): 445.