Comprehensive analysis of bioactive compounds in Pyxine farinosa Kashiw and Physcia integrata (Nyl.) arnold

This study presents a comprehensive phytochemical analysis of the lichens Pyxine farinosa (Pf) and Physcia integrata (Pi), assessing their value as sources of bioactive natural products. Methanol and chloroform extracts underwent qualitative, quantitative, and GC-MS/MS analyses. Both lichens contained alkaloids, phenolics, flavonoids, terpenoids, steroids, lipids, glycosides, coumarins, quinones, carbohydrates, and proteins. Chloroform extracts showed the highest levels of total phenolics (Pf: 703.20 ± 29.81 µg/mg; Pi: 722.43 ± 25.22 µg/mg) and flavonoids (Pf: 490.70 ± 22.33 µg/mg; Pi: 545.25 ± 22.74 µg/mg), indicating strong antioxidant potential. GC-MS/MS profiling identified abundant phenolic acids, flavonoids, and alkaloids, alongside rare metabolites such as epilupeol (anti-inflammatory, hepatoprotective), benzothiazole derivatives (antimicrobial, neuroprotective), and milbemycin B (suggestive of microbial symbiosis). Unique steroids, triterpenes, and high‑molecular‑weight lipids were also detected. These results expand the chemical diversity known in lichens and position Pf and Pi as promising candidates for bioprospecting, drug discovery, and ecological research.