Study of Phenolic Compounds and Antimicrobial Activity of Lavandula angustifolia L. Flowers Macerates

Abstract

Studies of total phenolic content and identification and quantification of phenolic compounds by HPLC-DAD from hydro-alcoholic and alcoholic macerates of Lavandula angustifolia L flowers from Dobrogea area are reported. The total phenolic content and the phenolic profile have been measured using Folin-Ciocalteau method, respectively adapted USP30 HPLC method in macerates of Lavandula angustifolia L flowers after 5 days of contact with either methanol (M1) or methanol: water 1 : 1 (V : V) mixture (M2). The values of TPC show that macerate M2 is more rich in phenolic compounds (3520 mg/100g d.w.), than in the case of macerate M1 (2860 mg/100 g d.w.). The obtained data of phenolic compounds determined by HPLC-DAD method were compared with the available authentic standards. Four individual phenolic compounds were found in macerate M1 and six individual phenolic compounds in macerate M2. Among gallic acid and chlorogenic acid, as major phenolic compounds, high concentrations of ellagic acid in M2 (514.249 mg/100 g d.w.) and M1 (499.487 mg/100g d.w.) were found. The antimicrobial activity of tested macerates indicates that Lavandula sp. has a moderate effect on the bacterial and Candida growth.

Biological Activity of Essential Sage Oil

“…The obtained results are similar with previous published studies concerning the total phenols concentration in essential sage oils from dry plants [1][2][3][4][5][6][7][8][9].…”

“…For Total Phenols Content (TPC) and antioxidant activity determinations a quantity of 0.1165 g of Salvia officinalis L. essential oil (ESO) obtained was brought to mark with ethanol to 10 mL volume. The total phenols content was estimated according to the Folin-Ciocâlteau method [9,10,[20][21][22][23][24]. The absorbance was measured at 681 nm.…”

“…The antioxidant activity was evaluated using DPPH Radical Scavenging test using two standard compounds to plot calibration curves: gallic acid (GA) and ascorbic acid (AA) and the results are expressed as equivalents (mg GAE and mg AAE, respectively). Absorbance measurements were carried out at 530 nm [9,20,22]. In 25 mL calibrated flasks, different volume of gallic acid or ascorbic acid solutions were added, then 5 mL DPPH 1.268 mM in methanol, filled up to the mark with methanol and let in the dark, to the room temperature for 45 minutes before the absorbance was determined at 530 nm using methanol as blank.…”

“…In the essential oil of S. officinalis were identified more than 120 components, the main components being: borneol, camphor, caryophyllene, cineole, elemene, humulene, ledene, pinene, and thujone [3,4], while the alcoholic extracts of S. officinalis exhibit a high content of rosmarinic acid and luteolin-7-glucoside but also caffeic acid and 3-caffeoylquinic acid. In the aqueous extract of S. officinalis were found high contens of rosmarinic acid and ellagic acid, followed by rutin, chlorogenic acid and quercetin [4,[6][7][8][9][10].…”

“…Several studies data indicates that sage essential oil contents monoterpenes (𝛼-and 𝛽thujone, 1,8-cineole, camphor), diterpenes (e.g., carnosic acid) triterpenes (oleanoic and ursolic acids) and some concentrations of phenolic compounds from which rosmarinic acid is the most abundant [2, 3-5, 8, 9]. It is well-known that high doses of -thujone in plants can be responsible to causes convulsions [4] and chronic exposure which can lead to neurotoxicity [1,2] and carcinogenicity [4], while optimal concentration of -thujone is effective in digestion stimulation, menstrual problems, as well as in the pain realise associated with rheumatism [4,6,[8][9][10][20][21][22][23][24]. Although the sage oil has a high thujone content, it has been estimated that it takes between 2 and 20 cups of sage tea to reach the acceptable daily intake of thujone [3,4].…”