Antimicrobial Activity Exerted by Total Extracts of Germander

Abstract

In the present research, ethanolic and methanolic extracts of Teucrium polium (germander) were studied regarding the content of biologically active substances - in particular polyphenols - antioxidant activity and antibacterial activity. The extracts have been found to be rich in polyphenolic compounds, kaempferol and epichatechin have been found to be present in the highest concentrations. The antioxidant activity evaluated by the method of capturing the free radicals with DPPH revealed values close to those produced by the ascorbic acid. Antimicrobial activity was evaluated by the diffusimetric method and S. aureus and E. coli microorganisms were found to be the most sensitive while P. aeruginosa and fungal species were not sensitive.

Comparative Chemical and Biological Activity of Selective Herbal Extracts

“…However, the hydrophilic/lipophilic character of the used solvents (diethyl ether, ethyl acetate and n-butanol) is different from ours (methanol, methanol/dichloromethane) which enabled also the extraction of the glycosides. Preliminary studies on Tunisian T. polium showed that the methanolic extract was richer in flavonoids and polyphenolic acids than the ethanolic extract [3]. Various iridoid glycosides were identified in Italian T. chamaedrys, but harpagide (for which we used HPLC grade standard) was detected only in T. polium and T. montanum samples [11].…”

“…Higher amounts of rosmarinic acid, caffeic acid and cinnamic acid were also identified. Similar compounds were identified in Teucrium chamaedrys from Serbia, Italy and Romania, T. polium from Iran, Tunisia and T. montanum from Serbia [1,3,11,14,18,20,[22][23][24][25]. In a comprehensive study, Panovska et al evaluated the chemical profile of three Macedonian endemic Teucrium species (T. chamaedrys, T. polium and T. montanum) [20].…”

“…Determination of total phenolics. Total phenolic compounds in the investigated extracts of Teucrium were determined with Folin-Ciocâlteu reagent [3,4,9,19] with gallic acid as a standard. Each sample was diluted to 1 mg/mL.…”

“…Their common characteristic is that they are perennial shrubs that prefer rocky and calcareous growing conditions, especially mountain forests, meadows and pastures from Europe and Anatoly [8,9,14,16]. Various research groups from these areas identified the same species as rich in essential oil, phenyl-glycosides iridoids and sterols with good antibacterial, antifungal and food preservative properties [1,3,11]. The available data suggests that different extracts from these species possess antioxidative, antimicrobial, antiviral, hepatoprotective, cytotoxic and antimutagenic effects, although the main investigated fraction was represented by the volatile oil [24,25].…”

Vegetal Compounds as Sources of Prophylactic and Therapeutic Agents in Dentistry

“…One of the areas in which natural compounds find their utility is the treatment of bacterial infections, given that modern medicine is currently facing a crisis of increasing resistance to conventional antibiotics [13]. In terms of composition, plants have over 2000 compounds that can be classified according to their chemical structure into four major groups: terpenoids, nitrogen compounds, sulfur compounds, and phenolic compounds [14,15].…”