Multi-experimental characterization of selected medical plants growing in the Czech Republic

Complex analysis of the impact of post-production conditions on antioxidant status, content of selected polyphenols, color, and concentration of selected metals was evaluated in the group of ten most popular medical plants conventionally produced in the Czech Republic. Ultraviolet visible near infrared spectroscopy (UV–VIS–NIR), electron paramagnetic resonance (EPR), high-performance liquid chromatography (HPLC), and inductively coupled plasma optical emission spectrometry (ICP-OES) were employed for these purposes. The entire data set of the obtained experimental characteristics was processed by multivariate statistical methods to assess the influence of the way of processing on sample properties. On the basis of 11 characteristics identified by the analysis of variance (ANOVA) as the most significantly different, successful differentiation of medical plant samples was achieved according to post-harvest treatment, families, and individual medical plant species by means of canonical discrimination method, reaching 100, 89.5, and 100% correctness, respectively. The importance of the sample processing on their properties and on the concentration of target naturally containing compounds with health-promoting and antioxidant properties was thus proved unambiguously.