Relationship of Anatomical Structures of Akebia quinata and Accumulation Part of Triterpenoid Saponins

The storing sites and contents of triterpenoid saponins,and anatomical structure of Akebia quinata were studied by means of histochemical localization,light microscope and quantitative analysis.The results showed that the contents of triterpenoid saponins accumulated in vegetative organs are arranged in the order of leavesrootsstems,which was identical with the results from histochemical examination.As to the same vegetative organ,the content of saponins was varied in different developing stages,and the changing pattern was as follows:old leavesyoung stemsyoung rootsyoung leavesold rootsold stems.Saponins were stored in a certain part of the vegetative organs separately,with roots in secondary phloem and phelloderm,stems in cortex and secondary phloem,and leaves in palisade tissue.The primary xylem is diarch,and most of the vessel in secondary xylem which are rich in fibers,are pore,a few are pore chain.More phloem fibers are distributed in stem,fiber bundles beyond the primary phloem and fiber ring round secondary phloem.The leaves are bifacial.