Chemical characterization and biological evaluation of Blumea napifolia essential oils: A combined experimental and molecular docking study

Essential oils (EOs) from the aerial parts (APEO) and roots (REO) of Blumea napifolia were investigated for the first time regarding their chemical composition, chemotaxonomic relationships, antioxidant and antifungal activities, and molecular docking analysis. The EO yields were 0.15±0.02% and 0.07±0.01% for APEO and REO, respectively. GC-MS analysis identified 63 and 55 constituents in APEO and REO, accounting for 94.16% and 97.40% of the total oils, respectively. Oxygenated monoterpenes were the predominant chemical class in both EOs, with carvotanacetone (31.51%) in APEO and thymohydroquinone dimethyl ether (20.93%) in REO as the major constituents. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) revealed that APEO and REO formed a distinct cluster characterized by high carvotanacetone content and were clearly differentiated from other Blumea species. Both EOs exhibited strong ABTS radical scavenging activity, with IC50 values of 6.54 ± 0.44 and 5.01 ± 0.11 μg/mL for APEO and REO, respectively, but showed only weak activity in the DPPH assay. In addition, the EOs displayed notable antifungal activity against soil-borne phytopathogenic fungi, particularly Sclerotium rolfsii and Rhizoctonia sp., with IC50 values ranging from 26.2 to 51.2 μg/mL. Molecular docking suggested that τ-cadinol and γ-muurolene exhibited the strongest binding affinities toward fungal CYP51 and the Keap1 Kelch domain, indicating their possible contribution to the observed antifungal and antioxidant activities. These findings provide the first comprehensive characterization of B. napifolia EOs and suggest their potential as natural sources of antifungal agents and selective radical-scavenging activity.