Chemical Composition and Acetylcholinesterase Inhibitory Activity of the Volatile Fraction from the Ecuadorian Moss Sphagnum magellanicum Brid

The volatile fraction (VF) of the aerial parts of Sphagnum magellanicum Brid. (Sphagnaceae), collected in southern Ecuador (2740 m a.s.l), was obtained for the first time by steam distillation using a Dean–Stark adapted apparatus and characterized by gas chromatography coupled to mass spectrometry (GC-MS) and flame ionization detection (GC-FID). A total of 89 compounds representing 95.28 ± 1.95% of the total VF were identified. The predominant chemical classes were n-alkanes (39.94%), alcohols (17.56%), sesquiterpene hydrocarbons (13.10%), and oxygenated sesquiterpenes (6.48%). Phytol was the major single compound (16.09 ± 0.07%), followed by n-tricosane (9.25 ± 0.82%), n-heneicosane (9.17 ± 0.54%), hexacosane (7.30 ± 0.99%), nonacosane (5.42 ± 0.14%), (Z)-caryophyllene (4.08 ± 0.32%), hexadecanoic acid (3.64 ± 0.25%), and dotriacontane (2.93 ± 0.21%). The VF was evaluated in vitro for acetylcholinesterase (AChE) inhibitory activity using the Ellman colorimetric assay, yielding a moderate inhibitory effect with an IC50 value of 77.0 ± 1.03 µg/mL. These results provide the first phytochemical and pharmacological characterization of S. magellanicum from Ecuador, establishing it as a potential source of bioactive volatile constituents with potential relevance for further pharmacological investigation.