Elemental composition and bioactivity of morphological parts extracts of winter savory (Satureja montana L.)

Abstract

Winter savory (Satureja montana L.) is well known to exhibit strong antioxidant and antibacterial properties. Winter savory is rarely found growing wild in Lithuania; however, as a common garden plant, it has been the subject of only a few studies. The goal of this research was to determine the mineral composition of winter savory and evaluate how well seven different solvents compositions – deionised water, 50% methanol (MeOH), 75% MeOH, 50% ethanol (EtOH), 75% EtOH, 2% sodium dodecyl sulfate (SDS) and 2% Triton X-100 – could extract phytochemicals. The results showed that the elemental composition was dominated by calcium (from 4231.23 ± 546.48 mg kg^–1 in stems to 11494.27 ± 785.01 mg kg^–1 in leaves) and potassium (from 3626.69 ± 427.98 mg kg^–1 to 6321.68 ± 241.53 mg kg^–1, respectively). It was also determined that the total concentration of phenolic compounds in the plant extracts varied depending on the solvent and morphological part used. Concentrations ranged from 23.91 mg g^–1 in the stems when ethanol was used to 138.96 mg g^–1 in the leaves when methanol was used. Additionally, phenolic acids ranged from 6.45 mg g–1 in the aqueous extract of flowers to 92.82 mg g^–1 in the leaf extract obtained with the surfactant Triton X-100. Flavonoid content varied from 9.94 mg g^–1 in flower extracts obtained with distilled water to 151.39 mg g^–1 in leaf extracts when the surfactant SDS was used. Winter savory extracts exhibited a high radical scavenging activity by DPPH assays ranging from 13.01 to 85.71%. The strongest antibacterial effect was observed in 2% SDS stem extract against Bacillus subtilis. Considering all the analysis performed, we can conclude that SDS is the most effective solvent for winter savory.