Influence of Essential Oil Composition on Antioxidant and Antibacterial Activities of Three Cultivars of Cymbopogon Flexuosus: In Vitro and In Silico Study

Abstract

The present study investigates and compares the chemical composition, antioxidant, and antibacterial properties of lemongrass essential oils (LEOs) extracted from fresh leaves of three cultivars of C. flexuosus: Krishna (CF‐KA), Cauvery (CF‐CA), and Nima (CF‐NI), grown in Chhattisgarh plains. Analysis through gas chromatography techniques revealed that citral content was highest in CF‐NI (79.82±1.00 %), followed by CF‐KA (69.75±2.70 %) and CF‐CA (54.75±1.22 %). In vitro antioxidant experiments demonstrated that CF‐CA had better scavenging capacity in DPPH (SC50=164.55±9.35 μg/mL) and ABTS (SC50=4.76±0.57 GEAC/g) free radical scavenging assays. The in vitro antibacterial experiments against Staphylococcus aureus (MTCC3160) and Escherichia coli (MTCC1687) demonstrated CF‐NI's enhanced antibacterial efficacy with significant inhibition zones and low MIC values. In silico molecular docking results revealed that LEO compounds like caryophyllene oxide, humulene epoxide, β‐caryophyllene etc. have better binding affinities towards targeted protein molecules responsible for bacterial cell mechanisms and production of reactive oxygen species (ROS) compared to their native ligands. Variations in biological activities among cultivars were potentially linked to the proportion of phytoconstituents in their chemical composition.