ABSTRACT Eryngium pyramidale Boiss. & Hausskn. is one of the species of the Apiaceae family, which is used as a spice in Iranian food. In this work, we aim to assess the phytochemical profile and antibacterial activity of the aerial parts of Eryngium pyramidale . The essential oil was obtained by hydrodistillation using a Clevenger apparatus. Then, it was quantitatively and qualitatively analyzed by GC-FID and GC-MS, respectively. The antibacterial activity of the essential oil was evaluated against six gram-positive and three gram-negative bacteria by the disc diffusion method and the broth microdilution assay. The phenolic and flavonoid contents of the methanolic extract were assessed using the UV spectrophotometry and HPLC-DAD. A total of 56 compounds representing 94.08% of the total oil were identified, among which sesquicineole (28.49 ± 1.2%) and (Z)-falcarinol (18.04 ± 0.7%) were the major ones. Based on the results, the oil was active against both gram-positive and gram-negative bacteria in comparison with standards. The phytochemical screening of the extracts revealed the presence of flavonoids, steroids, glycosides, and phenols in the methanolic, ethyl acetate, and n -hexane extracts. The total phenolic content of the methanolic extract was 0.36 ± 0.01 mg of gallic acid equivalents per g of dry plant materials, and the total flavonoid content of the methanolic extract was 0.90 ± 0.05 mg of quercetin equivalent (QE) per gram of dry plant materials. Five phenolic and flavonoid compounds in the methanolic extract including naringenin, rutin, apigenin, caffeic acid, and gallic acid were identified and quantified.

Abstract The present paper deals with free vibration of functionally graded fiber reinforced rectangular plates subjected to thermal loads. The rectangular plates are assumed orthotropic. The continuous grading fiber reinforced plates have a smooth variation in matrix volume fraction in the thickness direction. Two different types of volume fraction profiles through the thickness of plate are proposed: classic and symmetric. As the plate is thick, the equations of motion are derived based on three dimensional theory of elasticity. Inevitably, 3D General differential quadrature method is used instead of regular solving methods in order to discretize equations of motion equations as linear set of algebraic equations. The effects of temperature, volume fraction profiles, and boundary conditions are investigated. Some interesting conclusions obtained when the material properties were assumed to be temperature-dependent. It has been observed that temperature and functionality of FG plate have significant effect on the natural frequencies of the plate.