Chemical Profiling, Antioxidant and Antimicrobial Activities, and In Silico Evaluation of Gardenia jasminoides Essential Oil

Abstract

Aromatic and medicinal plants have been integral to human civilization for thousands of years, serving not only as vital components in traditional and modern medicine but also as sources of captivating fragrances that enhance our sensory experiences. The main objective of this study was to explore the chemical composition, antioxidant and antimicrobial properties, and in silico molecular docking attributes of Gardenia jasminoides essential oil (GJEO). The chemical compositions were determined using gas chromatography–mass spectrometry (GC-MS) analysis. The antioxidant activity was determined by 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and total antioxidant capacity (TAC) test. The antimicrobial activity was tested in vitro using three microbial strains (Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus), and two fungal strains (Candida albicans and Aspergillus niger). In silico analysis by molecular docking was used to determine the interaction types of topoisomerase II receptors and the most important antioxidant and antimicrobial compounds (Eugenol, Methyleugenol, and α-Terpineol ligands). The obtained results highlight the presence of 25 volatile compounds including 5 new detected compounds: Methyleugenol (15.41%), 1-Undecyne (3.4%), 2,6,10-Dodecatrien-1-ol, 3,7,11-trimethyl- (1.11%), 2,5-Cyclohexadiene-1,4-dione, 2,6-bis(1,1-dimethylethyl)- (0.4%), and 5,9-Tetradecadiyne (0.32%). The antioxidant capacity of GJEO is around 1.25 µg equivalent of ascorbic acid/mL for TAC assay and IC50 = 19.05 µL/mL for DPPH test. GJEO exhibited significant antimicrobial activity, particularly against Pseudomonas aeruginosa, with a minimum inhibitory concentration (MIC) of 16.67 µL/mL. In silico molecular docking analysis revealed strong interactions between ethyleugenol characterized by multiple bonding interactions, including Pi–Alkyl and carbon–hydrogen bonds, while α-Terpineol formed hydrogen and alkyl interactions. These results underline the potential of Gardenia jasminoides essential oil as a promising source of bioactive compounds with antioxidant and antimicrobial properties, highlighting its possible applications in pharmaceuticals and natural therapies.