Usnea diffracta Vain.

Usnic acid is a secondary metabolite of lichens with a unique dibenzofuran skeleton. Usnic acid inhibits DNA/RNA synthesis and has antibacterial activity. Usnic acid induces cell cycle arrest and apoptosis and has anticancer activity. Usnic acid inhibits RANKL-mediated osteoclast formation and function by reducing the transcriptional and translational expression of NFATc1. Usnic acid has antioxidant and anti-inflammatory activities by inhibiting lipid peroxidation and myeloperoxidase.

Diffractaic acid, a major constituent of U. longissimi, acts as an effective proapoptotic agent in various disorders research. Diffractaic acid is the analgesic and antipyretic component of Usnea diffracta.

Barbatic acid is an active compound.

Norstictic acid is a potent and selective allossteric transcriptional regulator. Norstictic acid shows anticancer activity. Norstictic acid shows antioxidant activity and antimicrobial activity.

Ethyl orsellinate is a lichen metabolite and a derivative of lecanoric acid with antiproliferative and antitumour activities. Ethyl Orsellinate is against A. salina for the cytotoxic activity with an LC₅₀ of 495 μM.

Usnic acid is a secondary metabolite of lichens with a unique dibenzofuran skeleton. Usnic acid inhibits DNA/RNA synthesis and has antibacterial activity. Usnic acid induces cell cycle arrest and apoptosis and has anticancer activity. Usnic acid inhibits RANKL-mediated osteoclast formation and function by reducing the transcriptional and translational expression of NFATc1. Usnic acid has antioxidant and anti-inflammatory activities by inhibiting lipid peroxidation and myeloperoxidase.