In vitro antiviral assessment against DNA and RNA viruses as well as antibacterial and antifungal profiles of selected Turkish species of the Salvia genus

The present study was undertaken to evaluate antibacterial, antifungal, and antiviral properties of the chloroform and methanol extracts from the aerial parts of fourteen Turkish Salvia species (Lamiaceae) including S. albimaculata Hedge & Hub., S. aucheri var canescens Boiss. et Heldr., S. candidissima ssp. occidentalis Vahl., S. ceratophylla L., S. cryptantha Montbret et Aucher ex. Benth., S. cyanescens Boiss. et Bal., S. frigida Boiss., S. forskahlei L., S. halophila Hedge, S. microstegia Boiss. & Bal., S. multicaulis Vahl., S. sclarea L., S. syriaca L., and S. verticillata L. ssp. amasiaca (Freyn, & Bornm.) against Escherichia coli, Pseudomonas aeruginosa, Proteus mirabilis, Klebsiella pneumoniae, Acinetobacer baumannii, Staphylococcus aureus, Bacillus subtilis, Enterococcus faecalis, and Candida albicans by microdilution method. Both Herpes simplex (DNA) and Parainfluenza-3 viruses (RNA) were used for the determination of antiviral activity of the abovementioned Salvia extracts by using Madin-Darby bovine kidney (MDBK) and Vero cell lines. The methanol extracts were found to be quite active against S. aureus and E. faecalis (2 and 4µg/mL, respectively), while the chloroform extracts were more active against S. aureus, B. subtilis, and E. faecalis (1, 2, and 2µg/mL, respectively). All of the extracts displayed the antifungal activity having the MIC value at 8µg/mL. Maximum cytopathogenic effect (CPE) concentrations as the indicator of antiviral activities of the extracts were determined and the chloroform extracts belonging to S. albimaculata, S. cyanescens, and S. microstegia (1–64µg/mL) along with the methanol extracts of S. ceratophylla, S. halophila, and S. sclarea (16–32µg/mL) showed reasonable antiviral effect. The cytotoxicity of the extracts was also expressed as the maximum non-toxic concentrations (MNTC), ranging between 16–128µg/mL.