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There is an ever-growing need to develop green, non-toxic, and eco-friendly procedures for synthesis and assembly of nanoparticles (NPs) with the desired morphologies and sizes. The hydroalcoholic extract of Persian oak leaves [Quercus brantii Lindl. (Fagaceae)] contains high content of phenolic and flavonoid compounds with strong antioxidant activities, and it seems that this plant can be considered a good candidate for metal nanoparticle synthesis.The potential of Q. brantii leaves in the production of silver NPs and the effect of the extract ethanol concentration on the produced NPs were studied.Quercus brantii leaves were freshly collected, air-dried at room temperature, powdered, and sieved. Hydroalcoholic extracts (70% and 96%) were prepared by percolation of the plant powder. The reaction mixtures contained (final concentrations): AgNO3 (1 mM) as the substrate, plant extract as the biocatalyst, and phosphate buffer (pH = 7, 100 mM) as the reaction medium. Silver ions were determined using atomic absorption analysis. Particle size distribution of NPs was analyzed using Nano-Zeta Sizer (Malvern Instruments Ltd, Malvern, UK). Samples for TEM were prepared by drop-coating the silver nanoparticle suspensions onto carbon-coated copper grids.Hydroalcoholic extract (96%) of Q. brantii successfully produced quite small (as small as 0.83 nm and the mean size of 6 nm), spherical, and poly-dispersed NPs with low aggregates. The conversion was fast and completed in 5 h.This plant and the extraction method seem to be quiet attractive for industrial scale production of NPs.

The objectives were to study the potential of Pulicaria gnaphalodes (Vent.) Boiss. aerial parts in production of nanoparticles and the effect of the extraction solvent on the produced nanoparticles. Methanol and dichloromethane extracts were prepared by percolation of the plant powder. Both the extracts of P. gnaphalodes (Vent.) Boiss. successfully produced small and polydispersed nanoparticles with low aggregates in early hours of the biotransformation. Methanol extract produced spherical and many single nanoparticles, whereas dichloromethane produced porous polyhedral and more aggregated nanoparticles. Methanol extract of this plant seems to be quiet useful for industrial scale production of nanoparticles.

This study was carried out to evalute antimicrobial activities of aerial parts of Inula viscosa (Asteraceae). Aerial parts of I. viscosa were collected in summer 2010 from Lazeghiyah, Syria. The powdered aerial part of the plant was extracted with acidic methanol. Methanolic extract was partitioned in distilled water and diethyl ether. The pH of aqueous parts were changed by adding NaHCO3 solution, and then extracted with chloroform to obtain non-phenolic compounds. The pH of aqueous part again was acidefied and extracted with ethyl acetate to obtain phenolic fraction. Antimicrobial activity tests were carried out using disc diffusion methods aginst five bacterial species. The results showed that different fraction of Inula viscosa extract was effective against Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella entritidis. Variation in antimicrobial activity of I. viscosa may be due to polarity of solvent used for extract prepration and the role of extract compositions on plant biological ...

Higher plants have been shown to be a potential source for the new anti-microbial agents. Essential oils are becoming increasingly popular as naturally occurring antimicrobial agents. In this work the chemical composition and the antimicrobial properties of Echinophora platyloba essential oils were determined. The aims of this work were to assess the antimicrobial properties of the essential oils isolated from the aerial parts of E. platyloba. The plant was collected from Isfahan and identified by Pharmacognosy Department of Isfahan Faculty of Pharmacy. Hydrodistillation was used to isolate the essential oils and the chemical analyses were performed by gas chromatography and GC coupled to mass spectrometry. The antimicrobial activity of the oils and components was determined against several microorganisms, using a disc agar diffusion method. Ciprofloxacin, ketoconazole and amphotericin B are used in the test as positive control. The GC-MS analysis showed that the major constituents of the oils we...