Chemical Characterization and Antioxidant, Antibacterial, Antiacetylcholinesterase and Antiproliferation Properties of Salvia fruticosa Miller Extracts

The Salvia fruticosa (Mill.) is the most medicinal plant used in Lebanon. The aim of this study is to investigate the phytochemical composition and the biological activities (in vitro) of its extracts. The plant was extracted by cold maceration with four solvents presenting an increasing polarity: cyclohexane (CHX), dichloromethane (DCM), ethyl acetate (EtOAc) and methanol (MeOH). The extracts were screened for their chemical composition by a HPLC-DAD detector for phenolic compounds identification and quantification and by GC-MS for volatile compounds detection. The antioxidant capacity (DPPH inhibition) was tested. Biological activities, mainly anti-Alzheimer activity (acetylcholinesterase inhibition), the antiproliferation of two human colon cancer cell lines (HCT-116 and Caco-2 cells) and antibacterial activity, were evaluated. Ten aromatic compounds were quantified by HPLC-DAD analysis. A total of 123 compounds were detected by GC-MS analysis. The MeOH extract showed a very interesting antioxidant activity with an inhibition percentage (IP) of 76.1% and an IC50 of 19.4 mu g/mL. The EtOAc extract exhibited the strongest inhibition against the acetylcholinesterase activity (IP = 60.6%) at 50 mu g/mL. It also strongly inhibited the proliferation of the HCT-116 cells (IP = 87.5%), whereas the DCM extract gave the best result with the Caco-2 cells (IP = 72.3%). The best antibacterial activity was obtained with the MeOH extract against Staphylococcus aureus (MIC = 1.2 mu g/mL) and with the EtOAc extract against Escherichia coli (MIC = 2.4 mu g/mL). This study highlights the chemical composition and therapeutic potential of S. fruticosa. It is important to mention that the following chemical compounds were identified for the first time in plant extracts: 2,6,11,15-tetramethyl-hexadeca-2,6,8,10,14-pentaene; 4,5,6,7-tetrahydroxy-1,8,8,9-tetramethyl-8,9-dihydrophenaleno [1,2-b]furan-3-one; podocarpa-1,8,11,13-tetraen-3-one,14-isopropyl-1,13-dimethoxy; podocarpa-8,11,13-trien-3-one,12-hydroxy-13-isopropyl-,acetate; 3 ',8,8 '-trimethoxy-3-piperidin-1-yl-2,2 '-binaphthyl-1,1 ',4,4 '-tetrone; and 2,3-dehydroferruginol, thus underlining the originality of this study.

Automated summary

This study investigated the phytochemical composition and biological activities (in vitro) of Salvia fruticosa (Mill.), the most medicinal plant used in Lebanon. The extracts, obtained using solvents with increasing polarity, were screened for their chemical composition and biological activities, including antioxidant, anti-Alzheimer, antiproliferation, and antibacterial activities. The results showed that the methanol extract exhibited strong antioxidant activity, the ethyl acetate extract showed the strongest inhibition against acetylcholinesterase activity, the dichloromethane extract had the best antiproliferation effect on HCT-116 cells, and the ethyl acetate extract demonstrated the strongest antibacterial activity against Escherichia coli. This study highlights the chemical composition and therapeutic potential of S. fruticosa, and identifies several compounds for the first time in plant extracts, emphasizing the originality of this research.