Profiling of aroma volatile compounds and antimicrobial potentiality of two Blumea species: A comparative insight of experimental and computational studies

The study's main objective is to characterize the aroma volatiles of two wild Asteraceae, Blumea axillaris (Lam.) DC. and B. laciniata (Wall. ex. Roxb.) DC. The essential oil was extracted through steam distillation and fractionated by organic solvents. The fractions (X to X/64th) were assayed for MIC and MBC using the microdilution method. The GC–MS method was used to characterize the volatile oils, and their antimicrobial mode of action was determined by molecular docking study. Only the ethyl acetate fractions showed the MIC at X/4th dilution against Aspergillus parasiticus, Bacillus cereus and Escherichia coli., but no MBC was recorded. The GC–MS study showed a significant variation among these species. The study concludes that these two species have distinct essential oil profiles with four comparatively small ligands. The molecular docking study supported the in vitro antimicrobial studies by identifying the most active compound [1H-Indole-2,3-dione, 1-(tert-butyldimethyl)] along with Methoxy-phenyl- Oxime, Phthalic acid butyl hexyl ester and Thymol phthalein of the extracted essential oil. Therefore, these essential oil compounds, alone or in combination, could be applied for topical antimicrobial therapy against bacterial and mould species.