Résumé
Objective: To search for the potential medicinal plant part of Gentiana macrophylla based on changes of secondary metabolites and trace elements in the flowers of G. macrophylla. Methods: HPLC was used to detect the changes of the active constituents (longanic acid, sweroside, gentiopicroside, and swertiamarin) and ICP-AES was used for mineral nutrients in G. macrophylla during flower development. And soluble sugar, starch, crude protein, hemicelluloses, cellulose, and lignin were determined. Results: Biomass of flower in full bloom (D2) phase was considerable during flower development, in which the contents of longanic acid and gentiopicroside were at the highest levels with 2.65 and 2.88 times higher than those recorded in Chinese Pharmacopoeia 2010, sweroside and swertiamarin in the flowers were reaching 6.06 and 1.25 times higher than those in roots. Florescence is the most valuable stage during flower development. The concentration of Fe, Mg, K, P, and B was higher in the flowers than that in roots. The accumulation of active constituents in the plant was influenced by the contents of metabolically linked carbon and nitrogen compounds. Conclusion: The secondary metabolites, mineral nutrients, and physicochemical indicators are tightly regulated by flower organ development, D2 is an important stage for both biomass and extraction of active constituents such as longanic acid. The flowers of G. macrophylla could be used as a potential medicinal plant part for longanic acid at a high level. © 2014 Tianjin Press of Chinese Herbal Medicines.