Salvia pratensis L. as a valuable source of phenolic compounds with promising antimicrobial activity

Salvia pratensis L. belongs to the genus Salvia, the largest genus in the Lamiaceae family. Salvia plants are used for various purposes since very early times in traditional medicine. Considering there are no available reports about S. pratensis, the study aimed to determine phenolic content and antimicrobial activity of S. pratensis aerial part (SPA) and root (SPR) methanol extracts as a starting base for further pharmacological research and potential application. Spectrophotometric determination of phenolic compounds in extracts showed high content of total phenolic compounds in both investigated extracts. SPR was richer in the contents of total phenolic compounds (177.85 mg GAE/g), condensed tannins (96.36 mg GAE/g), and phenolic acids (37.95 mg CA/g) while SPA had higher content of total flavonoids (68.46 mg QUE/g), flavonols (1.59 mg RUE/g) and monomeric and total anthocyanins (17.83 and 29.92 mg Cy 3 glc/g, respectively). In order to evaluate the antimicrobial activity of SPA and SPR, the microdilution method was used. SPR inhibited the growth of E. faecalis, B. cereus, B. subtilis, S. epidermidis, S. aureus, and S. typhimurium at a lower concentration than the lowest applied (MIC ˂ 0.156 mg/mL). SPA possessed lower antibacterial activity compared to SPR. As for antifungal activity, the extracts showed moderate activity against most of the tested fungal strains. S. pratensis root extract possesses promising antibacterial activity and obtained results may be a good basis for further research for its application and development of new antimicrobial natural products for pharmacy and/or foods.

This work was supported by the Ministry of Education, Science and Technological Development of the Republic of Serbia (Agreements No. 451-03-68/2020-14/200122 and 451-03-68/2020-14/200378).