RESUMEN
BACKGROUND: Many natural compounds have been identified and synthesized by the advancement of bryophytes phytochemistry studies. This work aimed to report the composition of Neckeropsis undulata (Hedw.) Reichardt moss volatiles, sampled in the Combú Island, Belém city, Pará state, Brazil. The volatile concentrate of N. undulata was obtained by a simultaneous distillation-extraction micro-system, analyzed by GC and GC-MS, and reported for the first time. RESULTS: Ten compounds were identified in the volatile concentrate, corresponding to 91.6% of the total, being 1-octen-3-ol (35.7%), α-muurolol (21.4%), naphthalene (11.3%), and n-hexanal (10.0 %) the main constituents. Most of the constituents of the N. undulata volatile concentrate have been previously identified in other mosses, and liverworts spread wide in the world. CONCLUSIONS: 1-Octen-3-ol, n-hexanal, 2-ethylhexanol, isoamyl propionate, and octan-3-one are already known metabolic products obtained from enzymatic oxidation of polyunsaturated fatty acids, belonging to the large family of minor oxygenated compounds known as oxylipins. The knowledge of the composition of volatiles from moss N. undulata could contribute to the Neckeraceae species' chemotaxonomy.