Rapid authentication of five medicinal seeds from Cruciferae family based on high-performance thin-layer chromatography

In addressing the time-consuming and labor-intensive issues inherent in traditional marker selection mode including systematic isolation, structural elucidation, and activity screening of indicator components for a single traditional Chinese medicine (TCM), the aim of this study was to develop a method for quick simultaneous identification of multiple medicinal drugs by using high-performance thin-layer chromatography (HPTLC) technique featuring the advantages of being intuitive, easy to operate, and offering multi-dimensional information. Taking three TCMs originating from five closely related different species from Cruciferae family as an example, the study conducted parallel comparisons of optimized TLC chromatograms of seeds from the five species Lepidium apetalum, Descurainia sophia, Raphanus sativus, Sinapis alba, and Brassica juncea under different detection wavelength lights; eight characteristic components were distinctly discovered, and among them one known common constituent identified as sinapine. Subsequently, seven characteristic components were isolated on a small scale and within a short-time, and elucidated structurally. Lastly, for each seed, a combination of the common constituent and most of one of its characteristic components were chosen as identification markers for the respective seed. To sum up, a unified HPTLC method with different detection wavelengths and different marker combinations was established for the simultaneous identification of five seed-originated medicines. This research approach, characterized by simplicity, cost-effectiveness, and rapidity, presents a highly efficient alternative for establishing identification methods for chemically similar multiple TCMs from closely related species.