Investigation of the Bioactive Properties of Tunisian Sage Extracts: A Detailed Analysis of Phytochemical Composition and their Antioxidant, Antibacterial, and Antibiofilm Activities

Salvia officinalis L. (common sage) provides a wealth of natural substances. Because of their numerous bioactivities, sage extracts garnered significant interest, especially in the fields of health and food preservation. The purpose of this research was to investigate the phytochemical composition and bioactive properties from the aerial part extracts of Tunisian sage using different organic solvent, focusing on their antioxidant, antibacterial and anti-biofilm effects. Following a series of maceration in solvents of increasing polarity, the various extracts were tested using Liquid Chromatography/Mass Spectroscopy (LC/MS) to identify their polyphenol profiles and their main bioactive components. DPPH and FRAP tests were used to evaluate the antioxidant activity. The efficacy against positive Gram stain pathogens, Staphylococcus aureus (MRSA) and Staphylococcus epidermidis, was tested to evaluate the antibacterial and anti-adherence effectiveness. Results demonstrated significant amount of rosmarinic acid in all extracts. Notably, cirsilineol was the main component in H1 extract. This extract showed a potent radical scavenging capacity, demonstrating an IC50 of 0.03 +/- 0.005 mg/mL in the DPPH assay and an EC50 of 0.17 +/- 0.015 mg/mL in the FRAP assay. Additionally, this extract displayed the most potent antibacterial potency (MIC = 0.156 mg/mL), and demonstrated the most effective biofilm inhibitory effect against MRSA at concentrations as low as 0.009 mg/mL. Hence, an in-silico molecular docking study was performed on the abundant molecules identified in the tested extracts to further investigate the observed biological activities. Our findings underscore the growing interest in sage extracts as natural alternatives in pharmaceutical and food safety formulations for enhancing food quality and health optimization.