Showing 82 results for Mohammad
Atiqullah Sultani Ahmadzai, Hamid Ejtehadi, Mohammad Farzam, Maral Bashirzadeh, Farideh Attar, Mohammad Reza Joharchi,
Volume 10, Issue 3 (12-2023)
Abstract
The new species Onosma nuristanica is described and illustrated here on the basis of specimens collected from Parun in Nuristan and Chapa Dareh in Kunar, one of the eastern provinces of Afghanistan. An extensive review of the literature and a comparative study with specimens from several herbaria led to the determine of this new species. Our results represent significant divergence between studied specimens in terms of the most important morphological features, i.e., flower color, pedicel length, bract length filaments length, cauline shape and form. In this article, a detailed description of the new species and a diagnostic key for Onosma species thriving in Afghanistan are provided and the new species is compared morphologically with its closely related species. In addition, a distribution map is provided for the new species and its close relatives in the area.
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.