The hexane extracts of flower, leaf, stem, and seed of Hypericum scabrum, which were collected from northwestern Iran, were obtained by extraction in a Soxhlet apparatus. The fatty acids were converted to methyl esters and determined by gas chromatography/flame ionization detector (GC/FID) and gas chromatography/mass spectrometry (GC/MS) systems. The hexane extract from the flower, leaf, stem, and seed contained 39.1%, 43.2%, 29.0%, and 37.6% of omega-3 fatty acids, respectively. The other main components of the flower extract were tetracosane (12.2%) and palmitic acid (9.3%), and that of the leaf extract was palmitic acid (7.4%). The stem and seed extracts contained bis(2-ethylhexyl)phthalate (18.7% and 35.7%), nonacosane (11.7% and 3.9%) and linoleic acid (6.5% and 6.9%) as major components. The hexane extracts of different parts from H. scabrum represent an important source of omega-3 fatty acids in several Hypericum species. The antioxidant activity of all hexane extracts was evaluated by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method. The results indicate that hexane extracts from different parts of H. scabrum possess considerable antioxidant activity. The highest radical scavenging activity was detected in seed, which had an IC 50 = 165 μg/mL. The antimicrobial activity of the extracts of those samples were determined against seven Gram-positive and Gram-negative bacteria (Bacillus subtilis, Enterococcus faecalis, Staphylococcus aureus, S. epidermidis, Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae), as well as three fungi (Candida albicans, Saccharomyces cerevisiae, and Aspergillus niger). The bioassay showed that the oil exhibited moderate antimicrobial activity. This study reveals that the all parts of this plant are attractive sources of fatty acid components, especially the essential ones, as well as of effective natural antioxidants.

The leaves and stem-bark of Lavandula officinalis were investigated for activity against some pathogenic organisms. Phytochemical screening revealed the presence of coumarins, tannins, flavonoids, volatile oil and fatty acids. Twenty six and twenty were characterized representing 84.5% (leaf oil) and 91.4% (stem oil) of the lot of components detected. The leaf oil of the major constituents was identified as borneol (23.6%), 1, 8-cineol (17.6%), camphor (12.6%). In the stem oil of plant 1, 8cineol (20.8%), borneol (19.2%), α-cadinol (11.3%), caryophyllene oxide (10.4%) and camphor (7.4%) were the predominating compounds. The hexane extracts of leaf and stem of plant were obtained by soxhlet apparatus. The fatty acids were derived to methyl esters and determined by gas chromatograph and mass spectrometer (GC/MS) systems. The main components of the leaf and stem (hexanic extracts) were ω -3 (43.2 and 21.0%), ω-6 (3.4 and 14.5%), palmitic acid (7.4 and 12.4%) and Bis (2-ethylhexyl) phthalate (12.8 and 16.7%), respectively. Antimicrobial activities of the crude methanol, hexane extracts and essential oil from leaf and stem were evaluated using agar diffusion method. Results, suggest potential antimicrobial activity of the essential oil and extracts of L. officinalis, which may find those application in future research for the food and pharmaceutical industry.

To develop a simple rapid procedure for biologically synthesis of silver nanoparticles (AgNPs) using methanol extract of Viburnum lantana leaves, the synthesized nanoparticles were characterized by UV-visible spectrophotometry, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Fourier transform infrared (FT-IR) spectroscopy. These phytosynthesized silver nanoparticles were tested for antibacterial and antifungal activities using disc diffusion method. The TEM study showed the formation of silver nanoparticles in the 20-80 nm range and average 48.1 nm in size. SEM showed the formation of silver nanoparticles with a mean size of 41.9 nm. The XRD study showed that the particles are crystalline in nature, with a face centered cubic structure. The silver nanoparticles showed the biological activity against Gram positive and Gram negative bacteria. V. lantana was found to display strong potential for the synthesis of silver nanoparticles as antimicrobial agents by rapid reduction of silver ions (Ag C to Ag ). The approach of phytosynthesized silver nanoparticles using V. lantana appears to be cost efficient, eco-friendly and easy alternative to conventional methods of synthesis.

A comparison of the chemical composition, and antioxidant and antibacterial activities of the essential oils obtained from the aerial parts of Thymus caucasicus, T. kotschyanus, and T. vulgaris was carried out. The oils, obtained by hydrodistillation, were analyzed by GC and GC/MS. Twenty, 29 and 22 compounds representing 94.8%, 96.6% and 98.2% of the essential oils of T. caucasicus, T. kotschyanus and T. vulgaris, respectively, have been identified. The oil of T. caucasicus was characterized by 1,8-cineol (21.5%), thymol (12.6%), β-fenchyl alcohol (8.7%), nerolidol (7.8%), terpinolene (7.2%), α-pinene (7.0%) and myrcene (6.8%). In the oil of T. kotschyanus, carvacrol (24.4%), β-caryophyllene (14.5%), γ-terpinene (12.4%), α-phellandrene (10.8%), p-cymene (9.8%) and thymol (6.8%) were the predominant compounds, whereas the main components of T. vulgaris oil were thymol (43.8%), p-cymene (15.2%), germacrene-D (11.7%), terpinolene (3.4%), carvacrol (3.2%), β-caryophyllene (2.8%) and α-thujene (2.2%). In all three plants oil, hydrocarbon monoterpenes predominated over sesquiterpenes. Antioxidant activities were assessed by determining IC 50 values in the DPPH radical scavenging assay. Antibacterial activity was determined by measuring minimum inhibitory concentration (MIC) using the broth dilution method. The essential oils of T. caucasicus, T. kotschyanus and T. vulgaris showed free radical scavenging and antibacterial activity.

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