Chemical composition, antimicrobial, antioxidant and cytotoxic activity of the essential oil from the leaves of Stachys pilifera Benth

Abstract

Stachys pilifera Benth is an endemic species of Stachys family found in Iran with a wide application as an herbal tea. The objective of this research was to evaluate the antimicrobial, antioxidant, and cytotoxic activity of the essential oil from the aerial parts of S. pilifera. Essential oil (EO) composition analysis showed that cis-Chrysanthenyl acetate (24.9%), viridiflorol (18.3%), trans-Caryophyllene (9.8%), caryophyllene oxide (4.6%), α-terpineol (3.3%), and linalool (3.1%) were the most abundant components. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the EO showed a higher antimicrobial activity against gram-positive bacteria (Bacillus cereus and Staphylococcus aureus) than gram-negative organisms (Escherichia coli, Shigella sonnei, Pseudomonas aeruginosa, and Salmonella enterica subsp. Enterica). The antioxidant activity of EO was studied using DPPH, FRAP, and β-carotene/linoleic acid assays. IC50 for the DPPH, FRAP, and β-carotene/linoleic acid tests were 23.2, 28.7, and 16.1 µg/mL, respectively, that it was higher than the results for BHT (p ≤ 0.05). The cytotoxic activity of the EO was evaluated using HT29 and HUVEC cells and it was observed that by increasing in EO concentration from 0.026 to 19.4 ug/mL, the viability of the cells for HT29 and HUVEC reduced to 6.8 and 7.1%, respectively. The results from this study suggest the possibility to use the essential oils from Stachys pilifera Benth as a natural preservative in processed or packaged food due to its high antibacterial, antioxidant, and cytotoxic activities.

Stachys pilifera Benth: A Review of Its Botany, Phytochemistry, Therapeutic Potential, and Toxicology

“…Various studies have identified over 30 compounds in the essential oil of S. pilifera . Composition studies of essential oils of S. pilifera revealed the most prevalent components to be cis-chrysanthenyl acetate (24.9% ), viridiflorol (18.3%), trans-caryophyllene (9.5% ), caryophyllene oxide (4.6% ), α -terpineol (3.3%), and linalool (3.1%) [ 28 ]. In another study, cis-chrysanthenyl acetate (24.9%), viridiflorol (18.3%), trans-caryophyllene (9.8%), caryophyllene oxide (4.6%), terpineol (3.3%), and linalool (3.1%) were detected in the EO of S. pilifera [ 29 ].…”

“…A study revealed that EO of S. pilifera had lower minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against Gram-positive bacteria ( Bacillus cereus and Staphylococcus aureus ) than Gram-negative bacteria ( Staphylococcus aureus and Bacillus subtilis ) ( Shigella sonnei, Escherichia coli, Salmonella enterica subsp. enterica, and Pseudomonas aeruginosa ) [ 28 ]. Farjam et al studied the activities of the n-butanolic extract of S. pilifera against Gram-positive and Gram-negative bacteria and fungi.…”

“…EO antioxidant activity was determined using the DPPH, FRAP, and beta-carotene/linoleic acid tests. The IC 50 values for DPPH, FRAP, and beta-carotene/linoleic acid were 23.2, 28.7, and 16.1 g/mL, respectively, which were significantly higher than those for BHT ( P ≤ 0.05) [ 28 ]. Jassebi et al provided some evidence on the significant antioxidant properties (DPPH assay) and total phenolic content (Folin–Ciocalteu assay) of the methanol extracts (80%) of S. pilifera .…”

“…The cytotoxic effects of the key ingredients of EO of S. pilifera, including monoterpenes (cis-chrysanthenyl acetate and linalool), were reported in some studies [ 35 , 36 ]. It was determined that increasing EO concentration from 0.026 to 19.4 μ g/mL reduced the viability of HT29 and HUVEC cells to 6.8 and 7.1%, respectively [ 28 ]. The methanolic and dichloromethane extracts of S. pilifera were evaluated against K562, MCF-7, and HL-60 cells.…”