Flavonoid constituents from the roots of Scutellaria baicalensis georgi grown in Viet Nam

In this study, four flavonoid compounds, including quercetin (1), kaempferol (2), apigenin (3), and baicalin (4) were isolated and structurally identified from the roots of Scutellaria baicalensis Georg (Hoàng Cầm) cultivated in Vietnam. The isolation procedure was conducted using a combination of modern chromatographic techniques, including thin-layer chromatography (TLC), column chromatography (CC), and high-performance liquid chromatography (HPLC). The chemical structures of the isolated compounds were elucidated through advanced spectroscopic methods such as high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) and one-dimensional and two-dimensional nuclear magnetic resonance spectroscopy (1D and 2D NMR). Although quercetin, kaempferol, and apigenin are widespread in many plant species, this study reports the first successful isolation of these three compounds (1–3) from S. baicalensis grown in Vietnam. These findings not only significantly enrich the current knowledge of the chemical constituents of S. baicalensis, but also provide a solid scientific foundation for future in-depth investigations into the pharmacological potential, structure - activity relationships, and underlying biological mechanisms of these compounds.