Samane Attaran Dovvom, Parvane Abrishamchi, Javad Assili,
Volume 3, Issue 2 (9-2016)
Abstract
Salvia leriifolia Benth. from Lamiaceae family is a plant native to Iran and Afghanistan with significant applications in medical, pharmaceutical and food industries. The aim of current investigation was to evaluate the composition and antioxidant activity of essential oils (EOs) of S. leriifolia growing naturally in Neyshabur and Bajestan (Northeast of Iran). The aerial parts of the plant were subjected to hydro-distillation and the EOs were analyzed with GC/MS. According to the results, 1,8-cineole (20.24%, 26.39 %), α-pinene (15.14%, 14.39 %) and β-pinene (24.33%, 26.01%) were the main constituents of the EOs of the plant populations in Bajestan and Neyshabur, respectively. Antioxidant activity of the EOs was measured by three different methods, 2,2´-diphenyl-1-picrylhydrazyl (DPPH), thiobarbituric acid reactive species (TBARS) and β-carotene bleaching (BCB). The total EO and three standards (α-pinene, β -pinene and 1,8-cineole) displayed a significant antioxidant effect in all assays. Antioxidant activities obtained by means of TBARS and BCB methods were higher than those measured by the DPPH assay. Moreover, BCB was proved to be the most appropriate method for measurement of antioxidant activity. The EOs of the plants grown in Neyshabur showed stronger antioxidant effects in comparison with those grown in Bajestan.
Bahare Asgari, Dr Ali Mohammadi, Dr Bahare Attaran,
Volume 11, Issue 1 (6-2024)
Abstract
The aim of the present work was to produce a stable nanoemulsion containing clove (Syzygium aromaticum) essential oil (PCLO) and evaluate its antimicrobial activity. The effect of the preparation technique, the type of surfactant and the ratio of surfactant to oil was evaluated to optimize the preparation formula of oil-in-water nanoemulsion. The optimized formula prepared by low energy production method containing 4% w/w PCLO and 12% w/w mixed surfactant (SDS + Tween 80) produced a clear and stable nanoemulsion for 90 days with an average particle diameter below 150 nm. The antibacterial activity of pure PCLO and its nanoemulsions (NCLO) was investigated by disk diffusion, agar well, and broth methods in 3 indicator bacteria of gastrointestinal infections, Escherichia coli, Staphylococcus aureus, and Salmonella typhimurium. Minimum inhibitory concentration (MIC) and bacteriocidal concentration (MBC) as well as dynamic killing time were determined in the tested bacteria. Strong antibacterial activity of PCLO and NCLO was revealed in the concentration range of 1000-2000 ppm. The killing kinetics study showed that during the first 15 minutes of exposure to NCLO at the MIC concentration, there was a rapid and extensive reduction in the amount of viable microorganisms. The presented data, considering the optimal performance of antimicrobial substances in food, cosmetics and chemical industries, can help in the rational design of nanoemulsion-based essential oil delivery systems.
Parichehr Hanachi, Zahra Adibi, Zahra Gharari, Bahareh Attaran, Roshanak Zarrin Ghalami,
Volume 12, Issue 2 (9-2025)
Abstract
Plant secondary metabolites like phenols and flavonoids neutralize free radicals and are linked to antioxidant and cytotoxic activities. Due to rising drug resistance in pathogens such as Salmonella paratyphi, Bacillus cereus, Escherichia coli, and Staphylococcus aureus, medicinal herbs are increasingly explored for antimicrobial properties. This study evaluated the total phenolic content (TPC), total flavonoid content (TFC), antioxidant capacity, and antibacterial effects of Arctium lappa. TPC, TFC, and antioxidant levels were measured using Folin-Ciocalteu, Aluminum chloride, FRAP, and DPPH assays, respectively. Antibacterial activities were assessed by microdilution broth and disc diffusion methods to determine MIC50 and MBC values. Results showed that A. lappa ethanolic extract, prepared with diluted water and the boiling method, had the highest flavonoid content (7.9 ± 0.40 mg/g DW). The leaves and flowers extract, using methanol and the boiling method, had the highest phenolic content (62.13 ± 0.73 mg/g DW) and antioxidant capacity. The ethanolic extract of A. lappa leaves also demonstrated the strongest antibacterial activity, with an MBC of 0.140 mg/mL and an 8 ± 0.4 mm inhibition zone against all tested bacteria. These findings suggest A. lappa bioactive compounds, particularly phenolics and flavonoids, offer promising potential for treating bacterial infections in pharmacognostic applications.
