Direct metabolic fingerprinting of commercial herbal tinctures by nuclear magnetic resonance spectroscopy and mass spectrometry

Tinctures are widely used liquid pharmaceutical preparations traditionally obtained by maceration of one or more medicinal plants in ethanol-water solutions. Such a process results in the extraction of virtually hundreds of structurally diverse compounds with different polarities. Owing to the large chemical diversity of the constituents present in the herbal tinctures, the analytical tools used for the quality control of tinctures are usually optimised only for the detection of single chemical entities or specific class of compounds.