A semi-targeted NMR-based chemical profiling of retail samples of Mexican gordolobo

Mexican gordolobo (MG) is one of the most important medicinal plants in Mexico and an important source of specialized metabolites with biological activities. The species employed in Mexican traditional medicine identified with this name are very different and difficult to identify according to existent criteria. In order to contribute to the identification of these species, a semi-targeted ¹H NMR-based chemometric method was developed to characterize the chemical profiling of retail samples of MG. Thus, 17 retail samples of MG flowers were successively extracted with a gradient of water:chloroform (1:4, 1:2 and 0:1) in an ultrasonic bath for 15 min each. The organic phase of the three extracts was pooled, evaporated and analyzed by ¹H NMR. The NMR data were subjected to multivariate statistical analysis, revealing that flavones gnaphaliin A (1), gnaphaliin B (2), araneol (3), 3,5,7-Tri-O-methylgalangin (4) and diterpenes sclareol (5) and kaur-16-en-18-oic acid (6) can be effectively used as chemotaxonomical markers for the correct identification of the Gnaphalium spp that compose MG. The aforementioned chemotaxonomic markers may be useful in establishing therapeutic criteria.