五叶木通营养器官解剖结构与三萜皂苷的积累关系

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

采用显微制片技术、组织化学定位和三萜皂苷定量分析方法,对五叶木通的营养器官分别进行了三萜皂苷的组织化学定位、含量和解剖结构特征研究。结果表明:三萜皂苷在五叶木通不同营养器官中的含量不同,含量测定与组织化学定位推测的结果吻合,叶>根>茎;三萜皂苷在同一营养器官的不同发育时期含量不同,总的规律是:老叶>幼茎>幼根>幼叶﹥老根﹥老茎。三萜皂苷在不同器官中具有明确的积累位置:根中主要是次生韧皮部和周皮;皮层和次生韧皮部是茎中三萜皂苷积累部位;叶内则以栅栏组织为主。五叶木通根中初生木质部二原型,次生木质部内导管多为单管孔,少数为管孔链,纤维含量丰富。茎中韧皮纤维丰富,在幼茎中纤维成束状罩在初生韧皮部的外方,在次生韧皮部中纤维呈带状环绕在外方。叶为异面叶。

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 leaves 〉 roots 〉 stems, 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 leaves 〉 young stems 〉 young roots 〉 young leaves 〉 old roots 〉 old 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.