[The development of secondary cells in the callus of Hypericum perforatum L. and hypericins accumulation]

Hypericum perforatum L. is a kind of traditional herbal medicine that has been used as an anti-depression medicine in Europe for centuries. One of its biological active compound, hypericins, is stored in the special secondary structure,black nodules,which located in the stems, leaves and flowers. Most researches focus on the development of the black nodules in vivo and how to culture the plant to produce more hypericins. We studied the process of de-differentiation from explants to callus and the pathway of hypericins biosynthesis in callus and cells of H. perforatum L. which reflected the relationship between the cell development and secondary metabolites accumulation. The morphogenesis of cells development and hypericins accumulation were studied by electron microscopy and histological technologies. Hypericins began to accumulate in a bunch of secondary cells located on the surface of the callus in late development period. Hypericins initially produced in the cytoplasm and were transported into the vacuole and then accumulated. E.R. took apart in the process of hypericins production. Theses results supplied the gap of hypericins production and accumulation in vitro and gave some useful information regarding mass-production hypericins by tissue and cell culture technology.