Quantitative Determination of Pregnanes from Caralluma fimbriata by using HPLC-UV Method and Identification by LC-ESI-TOF

Caralluma fimbriata, Fam. Asclepiadaceae, is a succulent plant and plants from Caralluma genus occur throughout Africa, and Asia, majority being indigenous to the Indian subcontinent and Arabian peninsula. Recently it has gained popularity as a weight-loss dietary supplement [1]. An HPLC method with UV detection for analysis of five pregnane compounds from Caralluma fimbriata was developed. The simultaneous chromatographic separation of the five compounds was achieved with a Gemini NX reversed phase C18 column, using gradient mobile phase of water and acetonitrile, both containing 0.1% acetic acid, aided with a detection using a PDA detector. This method was applied to the fingerprint identification of three plant materials of C. fimbriata and seven dietary supplements containing C. fimbriata. The five pregnane derivatives, boucerin (1), caraumbelloside I (2), caraumbelloside III (3), caraumbelloside II (4) and caraumbellogenin (5) have been quantitatively identified in the plant extracts. The limit of detection (LOD), and limit of quantitation (LOQ) were in the range from 1–5 µg/mL, and 3–15 µg/mL for compounds 1–5, respectively. This method also provides a distinction between the chromatographic profiles of Caralluma, Hoodia, and Opuntia spp., and thus can be aptly employed to distinguish between these plant materials or the botanical products thereof. In the ES positive ion mode, the [M+Na]⁺ ions at m/z 373.23, 679.33, 841.41, 517.27 and 355.22 were observed for compounds 1–5. Acknowledgements: This research is funded in part by “Science Based Authentication of Dietary Supplements” Funded by the Food and Drug Administration grant number 2 U01 FD 002071-07. References: [1] Kuriyan RT, et al. (2007) Appetite, 48: 338–344.

Fig. 1 Comparison of HPLC profiles of mixed standards (A); Caralluma fimbriata extract (B) and plant material (C), Hoodia gordonii (D) at wavelength 205 nm. (1) Boucerin, (2) Caraumbelloside I, (3) Caraumbelloside II, (4) Caraumbelloside II, (5) Caraumbellogenin.