Effects of ecological factors and gene expression of key enzymes on synthesis of major medicinal ingredients of Scutellaria baicalensis in autumn
【Abstract】 Objective To study the dynamic changes of the pharmacodynamic components of Scutellaria baicalensis in the harvest period and the effects of ecological factors and key enzyme expression on it. Methods The artificial cultivated annual S. baicalensis was studied and the expression of nine key enzyme genes (PAL, C4H, 4CL, CHS, CHI, FNS, F6H, UBGAT, and GUS) in the roots of S. baicalensis were determined by real-time quantitative PCR. The content of four main flavonoids (baicalin, wogonoside, baicalein, and wogonin) in the roots was determined by HPLC. The meteorological data of S. baicalensis were collected by the ecological meteorological station. SPSS statistical software and DPS statistical software were used for data analysis. Results The content of flavonoids of four monomers of annual S. baicalensis decreased slowly in autumn, so the best harvest time of S. baicalensis was in early September. The results of grey correlation analysis showed that the ecological factors affecting the four flavonoids were SWC, Max Ta, RH, and PAR. The expression of C4H and UBGAT genes had an important effect on the accumulation of flavonoids in the roots of S. baicalensis in autumn. Maximum rainfall intensity may indirectly affect the accumulation of the pharmacodynamic components of S. baicalensis by affecting the gene expression of key enzymes. Conclusion The dynamic changes of four main flavonoids of annual S. baicalensis in autumn and the expression of key enzyme genes of S. baicalensis annual are clarified, providing the theoretical basis for the clarification of the physiological and ecological mechanism of the biosynthesis of S. baicalensis and the improvement of the quality of S. baicalensis.
【Keywords】 Scutellaria baicalensis Georgi; flavonoids; key enzyme gene expression; ecological factors; medicinal materials quality; baicalin; wogonoside; baicalein; wogonin;
(Translated by ZHAO B)
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