Chemical Characterization, Antioxidant, Antimicrobial Potential, and Molecular Docking Studies on the Essential Oil of Festuca glauca

Abstract

Pharmacognostic recognition is growing for Festuca glauca, a perennial ornamental grass with a rich phytochemical profile. This species has shown potential in antibacterial and other therapeutic applications. The purpose of this work was to analyze the essential oil (EO) of Festuca glauca (F. glauca) for its chemical composition, antibacterial and antioxidant capabilities, and the interaction of its primary phytoconstituents with microbial targets using molecular docking. The EO was extracted using hydrodistillation and evaluated using Gas Chromatography-Mass Spectrometry (GC-MS). Antimicrobial activity was determined using diffusion, Minimum Inhibitory Concentration (MIC), Minimum Bactericidal Concentration (MBC), and dilution techniques. Antioxidant activity was assessed utilizing the (2, 2-diphenyl-1-picrylhydrazyl) DPPH and (2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)) ABTS assays. Piperitone's molecular docking was accomplished with Auto Dock, which is available in PyRx. The EO yield was 2% (w/w), with 31 components, piperitone (73.17%) being the main product. The EO showed significant antibacterial activity against Klebsiella pneumoniae (K. pneumonia) (27 mm inhibition zone) and Pseudomonas aeruginosa (P. aeruginosa) (28 mm), with MIC values ranging from 156.25-312.5 µg/mL. The antifungal activity was moderate, with Trichoderma wild displaying the maximum susceptibility (MIC = 625 µg/mL). In antioxidant tests, the EO showed IC₅₀ values of 18 µg/mL (DPPH) and 30 µg/mL (ABTS). Piperitone has high binding affinities to several microbial protein targets (−3.8 to −6.7 kcal/mol), which supports its biological activities. We concluded that the EO of F. glauca has excellent antibacterial and antioxidant properties, most probably owing to its high piperitone content, indicating its potential as a natural medicinal agent. More in vivo research, safety assessments, and formulation development are required to enable clinical and commercial use.