Essential oil composition and bioactivity profiling of Junipers from western Himalaya, India

The study investigated three Junipers that grow wild in western Himalaya, India to elucidate extent of yield, chemical variability present in essential oil composition (EOs) as well as their bioactivity potential. The EO yield in J. communis, J. indica and J. semiglobosa was 3.8%, 5.0% and 3.13% (v/w dry weight, aerial twigs), respectively. The gas chromatography-mass spectrometry (GC-MS) identification revealed a total 74 chemical constituents with high qualitative and quantitative variability among the three EOs. Predominance of monoterpene hydrocarbons, α-pinene, β-pinene, β-myrcene, sabinene, α-terpinolene and limonene in J. communis (70.94%) and J. indica (37.99%), while of oxygenated sesquiterpenes in J. semiglobosa (38.06%) EO was found. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) analyses based on 12 major volatiles clearly segregated all three EOs revealing high dependence on major chemical constituents’ concentration. The EO of J. indica revealed higher antioxidant activity than J. communis and J. semiglobosa. The antimicrobial profiling of EOs against 7 bacterial and 1 yeast strain evaluated using disc diffusion assay exhibited significant inhibitory effects (10-14 mm) against all microorganisms, except Pseudomonas aeruginosa. The MIC values ranged from 2-16% (v/v) against bacterial and 2% (v/v) against fungal pathogens. The findings of present study provide substantial basis for traditional usage of Junipers in medicine, besides other applications. It also finds them a potential resource to cater indigenous demand for raw material and livelihood generating to local communities.