A new antibacterial phenanthrenequinone from Dendrobium sinense

Area of Science:

• Natural Product Chemistry
• Medicinal Chemistry
• Pharmacognosy

Background:

• Dendrobium sinense is an endangered orchid endemic to Hainan Island.
• Phenanthrenequinones are a class of natural products with diverse biological activities.
• Ethnobotanical uses of Dendrobium species suggest potential medicinal properties.

Purpose of the Study:

• To isolate and characterize chemical constituents from Dendrobium sinense.
• To identify novel compounds with potential pharmaceutical applications.
• To evaluate the antibacterial activity of isolated compounds.

Main Methods:

• Phytochemical investigation of Dendrobium sinense whole plant extract.
• Isolation and purification of compounds using chromatographic techniques.
• Structure elucidation of the new compound using 1D, 2D NMR (COSY, HMQC, HMBC) and HR-ESI-MS.
• Antibacterial activity assay against Staphylococcus aureus using the disk diffusion method.

Main Results:

• A new phenanthrenequinone, denbinobin B (1), was isolated and characterized.
• Three known phenanthrene derivatives were also identified.
• Denbinobin B demonstrated moderate antibacterial activity against Staphylococcus aureus (inhibition zone diameter of 16.5 mm).

Conclusions:

• Denbinobin B is a novel phenanthrenequinone isolated from Dendrobium sinense.
• The findings contribute to the understanding of the chemical diversity of Dendrobium species.
• Denbinobin B shows potential as a lead compound for developing new antibacterial agents.