Studies On Structure, Accumulation Of Effective Components In Scutellaria Amoena C.H.Wright

Scutellaria amoena C.H.Wright(Labiatae Scutellaria Linn.) is a perennial herbaceous plant. Its root namely Chinese traditional medicine Dian Huang-qin, is mainly used in southwest of China. With regard to research on morphological structure, active ingredients and pharmacological effects of Scutellaria baicalensis Georgi, which is the related plants with S. a, included in the Pharmacopoeia of People's Republic of China, has been described in many reports by predecessors in recent years. However, little research which only include textual research of herbalism, pharmacognosy studies, tissue culture, etc, has been done on S. a. In this study, we systematically investigated the development and structure of nutritive organs, distribution and the dynamic changes of content of flavonoids from different organs, different growing stages, by using anatomy, histochemistry and phytochemistry methods, and then compared S. a with S. b, with a view to reveal the structure and development process of S. a, as well as the accumulation of flavonoids, providing a theoretical foundation and scientific guidance for the further research and development on S. a.1. The anatomical and development of nutritive organs of S. a are the same as other dicotyledons. The development of root could be divided into four stages, promeristem, primary meristem, primary structure and secondary growth stages. The primary xylem is diarch. The Casparian strip and starch grain can be clearly observed in the primary structure. The secondary growth mainly depends on the activities of vascular cambium and cork cambium. The cork cambium originates from pericycle cells. The thick-walled cells are distributed outside the secondary vascular bundles in stems and leaves, and are distributed together into one ring in the more mature stem tissue.2. The present histochemical results indicate that flavonoids is accumulated in the root of S. a from the primary growth stage. The pericycle and phloem in perennial root, and the parenchyma cells of epidermal and cortical in the stem and leaf, are the places where flavonoids is mainly accumulated. And the histochemistry results demonstrat that the color of relevant tissues in roots is deeper than in stems and leaves.3. The result of testing content of baicalin and flavone in vegetative organs of S. a in each growth period shows that the content of baicalin and flavone in the underground organs (roots) are higher than the aboveground organs (stems and leaves) in each period. It square with the histochemical results and indicate that root is main flavonoids storing position.4. In the same organs of S. a, the dynamic changes of content of baicalin and flavone are similar in different growth periods. Obviously the vegetative growth phase and the wilting stage are the two peak periods for accumulation of baicalin and flavone in roots, and the vegetative growth phase is the highest. However, the florescence phase is the peak period for accumulation of baicalin and flavone in stems and leaves.5. The result shows that the accumulation regularity of flavonoids in the underground organs (roots) and the aboveground organs (stems and leaves) present as one falls another rises. The vegetative growth stage and the wilting stage are the two peak periods for accumulation of flavonoids in roots and lowest in florescence stage. However, the accumulation of flavonoids in stems and leaves is highest in the florescence stage and lowest in the vegetative growth stage and the wilting stage. According to this accumulation regularity, growers can harvest roots in spring, stems and leaves in autumn, for better use of the plant resources of S. a.6. Anatomy, histochemical and phytochemistry results indicate that both the amount of parenchyma cells and the content of flavonoids in roots are increased from the primary growth stage to the secondary growth stage. So the content of flavonoids in nutritive organs has close relations with the amount of parenchyma cells. Structure of plant is closely related to distribution and accumulation of their secondary metabolites.7. The different results of anatomical structure, histochemistry and phytochemistry between S.amoena and S.baicalensis are also discussed in this paper. The obvious thick-walled cells are distributed in the more mature stem and leaf tissue of S.a, but are not found or not obvious in S.b. And the different histochemical and phytochemistry results between these two indicate that the content of flavonoids in S.a is higher than that in S.b. Therefore it is necessary to strengthen the comprehensive development and utilization on the endemics species (S.a).