A liquid chromatography-atmospheric pressure photoionization tandem mass spectrometric (LC-APPI-MS/MS) method for the determination of triterpenoids in medicinal plant extracts.

An analytical method using liquid chromatography-atmospheric pressure photoionization tandem mass spectrometry with toluene as a dopant was developed for the determination of triterpenes in medicinal plant extracts. The 12 compounds determined have been shown to exhibit biological activity, such as gastroprotective, hepatoprotective, anti-inflammatory, antiviral and anti-tumor effects. The parameters of the atmospheric pressure photoionization interface were optimized to obtain the highest possible sensitivity for all of the compounds. The limits of detection and quantification ranged from 0.4 to 157.9 µg l-1 and 1.3 to 526.4 µg l-1 , respectively. The method was validated and applied to extracts of five medicinal plants species (Mansoa alliacea (Lam.) A.H.Gentry, Bauhinia variegata var variegata, Bauhinia variegata var alboflava, Cecropia obtuse Trécul and Cecropia palmate Willd) from the Amazonian region. The concentrations of the six triterpenes quantified in the samples ranged from 0.424 mg kg-1 for ursolic acid to 371.96 mg kg-1 for β-amyrin, which were quantified by using the standard addition method (n = 3). Copyright © 2016 John Wiley & Sons, Ltd.