Comparison of the essential oils of Ferula orientalis L., Ferulago sandrasica Peşmen and Quézel, and Hippomarathrum microcarpum Petrov and their antimicrobial activity

Objectives: To determine the chemical composition and antimicrobial activity of the essential oils of the aerial parts of Ferula orientalis L., roots of Ferulago sandrasica Peşmen and Quézel, and aerial parts of Hippomarathrum microcarpum Petrov.Materials and Methods: Essential oils were analyzed by gas chromatography and gas chromatography/mass spectrometry. The antimicrobial activity of the essential oils was determined by bioautography assay.Results: α-Pinene (75.9%) and β-pinene (3.4%) were the major components of the aerial parts of F. orientalis; with limonene (28.9%), α-pinene (15.6%), and terpinolene (13.9%) for F. sandrasica; and β-caryophyllene (31.4%) and caryophyllene oxide (23.1%) for the aerial parts of H. microcarpum. Essential oils from the aerial parts of F. orientalis, the roots of F. sandrasica, and the aerial parts of H. microcarpum were active against Staphylococcus aureus and Candida albicans strains. However, essential oils were not active against Pseudomonas aeruginosa or Escherichia coli.Conclusion:The antimicrobial activities against S. aureus and C. albicans of these species may be attributed to the presence of the main components in the essential oils

pH and molecular weight dependence of auric acid reduction by polyethylenimine and the gene transfection efficiency of cationic gold nanoparticles thereof

Small, cationic gold nanoparticles (GNP) are produced by the direct reduction of auric acid in a non-reducing solvent, water, with branched polyethylenimine (bPEI) in a broad pH range (3.0–9.0). Basic pH, which is studied for the first time, emerged as a favorable condition to achieve good reducing power and surface passivation simultaneously, providing smaller particles (hydrodynamic size ca. 6 nm) with enhanced long-term stability and a sharper surface plasmon peak (SPP). This synthetic method produces colloidal GNPs with bPEI in a broad molecular weight range (0.6, 1.8, 10 and 25 kDa). The molecular weight did not influence the crystal size much but did affect the hydrodynamic size and the stability. 0.6 kDa bPEI provides the largest GNPs (ca. 100 nm aggregates) which lack long term stability. 1.8 kDa bPEI provides small particles (hydrodynamic size ca. 7 nm) with the sharpest SPP. The GNPs prepared with 25 and 1.8 kDa bPEI show no significant cytotoxicity in HEK 293T cells and PEI25–Au transfects green fluorescent protein (GFP) into HEK 293T cells more efficiently (82%) than FuGENE® (50%). This simple one pot synthesis of cationic GNPs in water is a valuable, simple alternative for the generation of new cationic GNPs in water with even low molecular weight PEI