The chemical composition of the Tamarix boveana volatile oils obtained from the whole aerial part, flowers, leaves and stems by steam distillation was analysed using gas chromatograph (GC)-flame ionization detectors (FID) and GC-MS. Sixty-two components were identified. Hexadecanoic acid (18.14%), docosane (13.34%), germacrene D (7.68%), fenchyl acetate (7.34%), Benzyl benzoate (4.11%) were found to be the major components in the whole aerial parts. This composition differed according to the tested part: 2.4 Nonadienal was the main compound in the flowers (12.13%) while germacrene D was the major component in leaves (31.43%) and hexadecanoic acid in the stems (13.94%). To evaluate in vitro antimicrobial activity, all volatile oils were tested against six Gram-positive and Gram-negative bacteria and four fungi. The T. boveana volatile oils exhibited an interesting antibacterial activity against all strains tested except Pseudomonas aeruginosa but no antifungal activity was detected.

The chemical composition of the volatile fractions obtained by steam distillation from the capitula (C) and the aerial parts of Rhaponticum acaule DC were analysed by GC-MS. From the 57 identified constituents, representing 95.5% and 96.3% of the two oils, respectively, methyl eugenol, epi-13 manool, beta-ionone, beta-bisabolol, 1-octadecanol, phytol and farnesyl acetate were found to be the main components. Furthermore, the oils were tested against six Gram-positive and Gram-negative bacteria and four phytopathogenic fungi. It was found that oils from both parts of R. acaule, and especially that of C, exhibited interesting antibacterial activity, but no antifungal activity was observed.

Antimicrobial activity of methanolic extracts obtained from the aerial parts of Evax pygmaea was tested against five bacteria and two strains of phytopathogenic fungi using the agar diffusion and broth microdilution methods. Antioxidant properties were evaluated through the ability of the different fractions to scavenge the stable ABTS (2,2 0 -azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)) and DPPH (1,1-dip henyl-2-picrylhydrazyl) radicals. The TEAC (Trolox Equivalent Antioxidant Capacity) and IC 50 values of the fractions were calculated and compared. The experimental data indicated that all fractions exhibit moderate to appreciable antibacterial activities against all Gram-positive cocci and Gram-negative rods except Pseudomonas aeruginosa, but no antifungal activity was observed. Ethyl acetate and methanol fractions were found to cause significant free radicalscavenging effects in both assays. These results may suggest that E. pygmaea could be used as a natural preservative ingredient in the food and/or pharmaceutical industries.

No abstract

The chemical composition of the volatile constituents from the flowering parts of Suaeda fructicosa and Limonium echioides were analysed by GC-FID and GC-MS. Sixty-five compounds were identified in L. echioides aerial parts. 48 out of 65 were found common to the aerial part of S. fructicosa. Palmitic acid was found as a predominant compound in both tested halophytic oils. Furthermore, the essential oil was tested against six bacteria and four fungi at different concentrations. Both oils, tested at 0.5 and 0.8 mg ml -1 , inhibited the visible growth of Staphylococcus aureus, Staphylococcus epidermidis, Micrococcus luteus, Escherichia coli and Salmonella typhimurium, but no antibacterial effect was detected against Pseudomonas aeruginosa. Additionally, both halophytic oils failed to show antifungal activity against all the test fungi when applied at 80, 200 and 500 lg/disc.

The volatile constituents of the aerial parts of Scorzonera undulata Vahl subsp. deliciosa (Guss.) Maire obtained by steam distillation were analyzed by GC and GC/MS. Thirty six constituents were identified in the oil and the main components of which were methyl hexadecanoate (30.4%), methyl linolenate (23.9%) and heneicosane (12.2%) The antimicrobial activity of the oil was also investigated. The Scorzonera undulata subsp. deliciosa oil exhibited an interesting antibacterial activity against Gram-positive and Gram-negative bacteria except for Pseudomonas aeruginosa but no antifungal activity was detected.

No abstract

The petroleum ether, chloroformic, ethyl acetate and methanolic extracts of Limonium echioides L. (Plumbaginaceae) were screened for their antioxidant and antifungal activities through in vitro experiments. The 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) diammonium salt (ABTS•+) decolorization and 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH•) free radical‐scavenging method were used. All extracts were active with radical‐scavenging capacity reaching 100% in DPPH• reaction system and 85.6% in ABTS•+ reaction at the used concentrations. Methanolic extract was found to possess the highest free radical‐scavenging effects in both assays. An important correlation between antioxidant capacities and total phenolic contents of the polar extracts was found. The gallic acid, identified in this plant, seemed to be active against both radicals DPPH• and ABTS•+. The mycelium growth inhibition method was used for the antifungal testing. Ethyl acetate and methanolic extracts of L. echioides showed antifungal activities against Fusarium oxysporum and Penicillium sp. PRACTICAL APPLICATIONS This study may prove to be beneficial in the exploitation of natural antioxidant and antifungal sources, containing a large amount of phenolics, for the preservation and/or extension of the shelf life of raw and processed foods. Then, this could also be applied in the area of pharmaceuticals for the protection of human life.