Biologically active compounds in Scutellaria baicalensis L. callus extract: Phytochemical analysis and isolation

Abstract

Plant cells and tissue cultures are sources of secondary plant metabolites. Substances produced by callus cultures can expand the raw material base in pharmacy and food production. However, isolating biologically active substances from medicinal plants is a labor- and time-consuming process. As a result, new and efficient technological processes adapted for extraction from callus cultures are in high demand, and new algorithms of isolation and purification of biologically active substances remain a relevant task. This research featured callus cultures of Scutellaria baicalensis. The procedures for phytochemical analysis and isolation of biologically active substances involved such physicochemical research methods as high-performance chromatography (HPLC), thin-layer chromatography (TLC), UV spectrometry, and IR spectrometry. The high performance liquid chromatography confirmed the presence of flavonoids represented by baicalein (5,6,7-trioxyflavone), baicalin (baicalein 7-O-glucuronide), scutellarein (5,6,7,4-tetraoxyflavone), scutellarin (7-O-glucuronide scutellarein), vagonin, and oroxylin. The spectral analyses also detected skutebaicalin. The highest total content of diterpene belonged to the samples extracted with 70% ethanol at 70°C. The content of diterpene was 0.09 mg/cm3 in terms of betulin. The biologically active substances were isolated from the callus extracts of S. baicalensis with a recovery rate of ≥ 80%. The purification scheme made it possible to obtain highly-pure individual biologically active compounds: trans-cinnamic acid, baicalin, and oroxylin A had a purity of ≥ 95%; baicalein had a purity of ≥ 97%; scutellarin and luteolin reached ≥ 96%. The new technological extraction method made it possible to obtain extracts from S. baicalensis callus cultures, which were tested for the component composition. The developed isolation algorithm and purification scheme yielded biologically active substances with a purification degree of ≥ 95%.