Scutellaria baicalensis: The End of the Flavone Biosynthesis Pathway

The report demonstrates that plenty of methylated flavones of the plant, as the end product of the flavone biosynthesis pathway, are concentrated in the root bark, which largely remains in the waste that makes up 7% w/w of the commercial root and is discarded. The study of the waste extract showed that the last enriched with monomethylated flavones wogonin and oroxylin A, along with some polymethylated ones represent an end of the biosynthesis pathway of flavones in the plant. In addition to wogonin, 7 known methylated flavones were found for the first time in the root bark. Due to a high content of wogonin and oroxylin A in the extract, these flavones were concentrated using preparative liquid chromatography. As a result, the obtained complex of these two target flavones turned out to be 0.8% w/w of the waste. Such morphologically specific accumulation of methylated flavones at the root boundary raises the question of their role in plant life.