Micro-2D-TLC separation of phenolics in some species of mint and their fingerprints on diol bonded polar stationary phase

Abstract

Summary. Micro-thin-layer chromatography in two dimensional (2D-mTLC) mode in normal and reversed phase systems by use of diol bonded stationary phase was applied to make fingerprints of 11 species of Mentha genus and two finished pharmaceutical products.Nonaqueous eluents (propan-2-ol or ethyl acetate dissolved in n-heptane) were used in normal phase systems. Mixtures of acetonitrile with water were used in reversed phase chromatographic systems.Optimization of one dimensional systems was performed by determining of R F vs. composition of mobile phases dependencies for standards occurring in various species of Mentha. Most selective eluents were chosen to optimize two-dimensional systems by creating R F in normal-phase (NP) systems vs. R F in reversed-phase (RP) systems correlations.2D-mTLC on diol polar bonded stationary phase were optimized to separate phenolic compounds and make fingerprints of examined plant materials and this method was never applied earlier in the chromatographic analysis.

Extraction and identification of major polyphenol constituents of Northern Hungarian horsemint (Mentha longifolia L. (L.))

“…Caffeic acid derivatives (predominantly the known antiradical molecule rosmarinic acid) are present. But flavonoids also deserve attention: the presence of 55 different flavonoids was reported (Bourwieg and Pohl 1973;Ghoulami et al 2001;Pereira and Cardoso 2013Hawrył et al 2016, Patonay et al 2017Park et al 2019), six of them de novo (Sharaf et al 1999;Jahan et al 2001;Ghoulami et al 2001;Ali et al 2002). Regarding flavonoid subclasses, flavones seem to be present in the largest variability.…”