Extensive Phytochemical Assessment of Dendrobium fimbriatum Hook (Orchidaceae)

Abstract

Dendrobium fimbriatum Hook is an important medicinal and ornamental orchid that may lead to important drugs and cosmetics. In this study, 2 analytical strategies were combined to describe the detailed composition of a hydroethanolic extract of the whole plant. The CARAMEL approach, based on centrifugal partition chromatography and nuclear magnetic resonance data interpretation, allowed the rapid dereplication of 21 major constituents, mainly including polyols, nucleosides, zwitterionic compounds, phenolic compounds, and organic acids. Further semipreparative high-performance liquid chromatography and spectroscopic analyses led to the isolation of 6 additional compounds; 4 phenanthrenes (plicatol B, hircinol, plicatol A, and plicatol C), 1 bibenzyl (3′,4-dihydroxy-3,5′-dimethoxybibenzyl), and 1 furostanol saponin (protodioscin), as well as a new phenanthrene derivative, plicatol D. A total of 28 metabolites were structurally elucidated, among which 23 are described for this species for the first time.