Characterization and Antioxidant Activity of Volatile Constituents from Different Parts of Aframomum danielli (Hook) K. Schum

Background: Aframomum danielli is used in ethno-medicine for the treatment of several ailments and as a traditional food spice. Methods: The hydro-distilled leaf, stem, seed, rhizome and pod volatile oils of A. danielli were subjected to gas chromatography-mass spectrometry (GC-MS) analysis. Free radical scavenging capacity of the volatile oils was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays. Results: Thirty-nine (39) volatile compounds were identified in the oils of A. danielli, accounting for 85.33 to 96.03% of the total oil composition. The leaf, stem, rhizome and pod volatile oils were dominant in β-pinene (30.94–47.55%), while the seed oil contained a high amount of 1,8-cineole (eucalyptol) (53.44%). The seed oil showed higher radical inhibitory activity in the DPPH assay (IC(50) value, 45.5 µg/mL) and the rhizome oil was the most effective in the FRAP assay. Conclusions: The characterization of the leaf, stem, rhizome and pod volatile oils of A. danielli is reported for the first time. A. danielli seed and rhizome oils elicit promise as potential plant resource and warrant further biological exploitation.