Essential oil analysis and antibacterial activity of Ferula assa-foetida L. aerial parts from Neishabour mountains

Abstract Background and objectives: Ferula assa-foetida (asafoetida) is a native Iranian species which grows in different regions and climates in Iran. The plant is well known in Iranian Traditional Medicine as well as folk medicine for treatment of diseases. Several studies have been carried out on the essential oil of this species collected from different areas of Iran. This study is the first report about the essential oil of the plant collected from Neishabour mountains that is a potent area for growing this valuable plant species. Methods: Essential oil of the aerial part of Ferula assa-foetida which was collected from Neishabour, Iran, was analyzed by gas chromatography-mass spectroscopy (GC/MS). The minimum inhibitory concentrations of the essential oil was investigated against both Grampositive (Staphylococcus epidermidis, Staphylococcus aureus, Bacillus subtilis) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumonia) bacteria using microdilution method. Results: Twenty three components representing 97.06% of the total oil were identified. (E)-1-propenyl sec-butyl disulfide (53.77%), (Z)-1-propenyl sec-butyl disulfide (35.6%) and α-pinene (3.4%) were identified as major components. The MIC of the essential oil ranged from 12-24 mg/mL against all tested bacteria. Conclusion: The results indicated that among various compounds identified in the essential oil of F. assa-foetida L. from Neishabour mountains, disulphide compounds were the major constituents of the oil. In comparison to other reports of this plant around the country, disulphide compounds could be the reason of its moderate antibacterial effect

A flexible phased array system with low areal mass density

Phased arrays are multiple antenna systems capable of forming and steering beams electronically using constructive and destructive interference between sources. They are employed extensively in radar and communication systems but are typically rigid, bulky and heavy, which limits their use in compact or portable devices and systems. Here, we report a scalable phased array system that is both lightweight and flexible. The array architecture consists of a self-monitoring complementary metal–oxide–semiconductor-based integrated circuit, which is responsible for generating multiple independent phase- and amplitude-controlled signal channels, combined with flexible and collapsible radiating structures. The modular platform, which can be collapsed, rolled and folded, is capable of operating standalone or as a subarray in a larger-scale flexible phased array system. To illustrate the capabilities of the approach, we created a 4 × 4 flexible phased array tile operating at 9.4–10.4 GHz, with a low areal mass density of 0.1 g cm^(−2). We also created a flexible phased array prototype that is powered by photovoltaic cells and intended for use in a wireless space-based solar power transfer array

Essential oil analysis and antibacterial activity of Ferula assa-foetida L. aerial parts from Neishabour mountains

Background and objectives: Ferula assa-foetida (asafoetida) is a native Iranian species which grows in different regions and climates in Iran. The plant is well known in Iranian Traditional Medicine as well as folk medicine for treatment of diseases. Several studies have been carried out on the essential oil of this species collected from different areas of Iran. This study is the first report about the essential oil of the plant collected from Neishabour mountains that is a potent area for growing this valuable plant species. Methods: Essential oil of the aerial part of Ferula assa-foetidawhich wascollected from Neishabour, Iran, was analyzed by gas chromatography-mass spectroscopy (GC/MS). The minimum inhibitory concentrations of the essential oil was investigated against both Gram-positive (Staphylococcus epidermidis, Staphylococcus aureus, Bacillus subtilis) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumonia) bacteria using microdilution method. Results: Twenty three components representing 97.06% of the total oil were identified. (E)-1-propenyl sec-butyl disulfide (53.77%), (Z)-1-propenyl sec-butyl disulfide (35.6%) and α-pinene (3.4%) were identified as major components. The MICof the essential oil ranged from 12-24 mg/mL against all tested bacteria. Conclusion: The results indicated that among various compounds identified in the essential oil of F. assa-foetida L. from Neishabour mountains, disulphide compounds were the major constituents of the oil. In comparison to other reports of this plant around the country, disulphide compounds could be the reason of its moderate antibacterial effect