Germination Characteristics and Secondary Metabolism Regulation of Scutellaria baicalensis Georgi under Different Illumination Time.

[Objective] This study aimed to investigate the primary and secondary metabolism of Scutellaria baicalensis Georgi during seed germination process under different illumination time. [Method] Chlorophyll (CHL) content, soluble sugar content, phenylalanine ammonia lyase (PAL) activity and cinnamate-4-hydroxylase (C4H) activity were determined with ultraviolet spectrophotometry. The secondary metabolites were detected by high performance liquid chromatography (HPLC). [Result] The results indicated that the germination of S. baicalensis seeds was not sensitive to light and the seedlings were very sensitive to light. CHL content, soluble sugar content, PAL activity and C4H activity increased continuously with the illumination time. The secondary metabolites showed a similar trend. [Conclusion] Illumination time promoted the formation of leaf photosynthetic pigments, thereby affecting the synthesis of primary and secondary metabolites and the activities of PAL and C4H. Therefore, the quality of S. baicalensis can be improved by regulating the illumination time appropriately. [ABSTRACT FROM AUTHOR]