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The main objective of this research was to evaluate the impact of methanolic, ethanolic and aqueous extracts of Origanum majorana L., Origanum vulgare L., Teucrium chamaedrys L., Teucrium montanum L., Thymus serpyllum L. and Thymus vulgaris L. (Lamiaceae) on the effects of free radicals using different model systems. The extracts were characterized on the basis of the contents of total phenolics, phenolic acids, flavonoids and flavonols, and also using high-performance liquid chromatography with diode-array detection. Antioxidant activity in vitro was assessed using DPPH assay. The genoprotective properties were tested using plasmid relaxation assay on pUC19 E. coli XL1-Blue, while SOS/umuC assay on Salmonella typhimurium TA1535/pSK1002 and Comet assay on human lung fibroblasts were used to assess the antigenotoxicity of the extracts. Ethanolic extracts had the most phenolics (up to 236.20 mg GAE/g at 0.5 mg/mL), flavonoids (up to 42.47 mg QE/g at 0.5 mg/mL) and flavonols (up to 16.56 mg QE/g at 0.5 mg/mL), and they exhibited the highest DPPH activity (up to 92.16% at 0.25 mg/mL). Interestingly enough, aqueous extracts provided the best protection of plasmid DNA (the lowest IC50 value was 0.17 mg/mL). Methanolic extracts, on the other hand, most efficiently protected the prokaryotic DNA, while all the extracts had a significant impact against genomic damages inflicted on human fibroblasts. O. vulgare extracts are considered to be the most promising in preserving the overall DNA integrity against oxidative genomic damages. Moreover, HPLC-DAD analysis highlighted rosmarinic acid as the most abundant in the investigated samples (551.45 mg/mL in total in all the extracts), followed by luteolin-7-O-glucoside (150.19 mg/mL in total), while their presence correlates with most of the displayed activities. The novelty of this study is reflected in the application of a prokaryotic model for testing the antigenotoxic effects of Lamiaceae species, as no previous reports have yet been published on the genoprotective potential of these species.

In this paper, we analyzed the capitula essential oil composition of seven Centaurea species, six of which belong to Centaurea calocephala complex, and the related species Centaurea melanocephala Pančić (subgenus Acrocentron, tribus Cardueae, subtribus Centaureinae) which inhabit Balkans Peninsula. The volatile organic compounds were extracted by simultaneous distillation extraction, using Likens-Nickerson type apparatus and the oils were analyzed by GC-FID and GC-MS. In total, 146 compounds were identified (95.5–99.4% of the total oil composition). The essential oils were dominated by sesquiterpenes (39.1–81.7%). The most abundant components were β-caryophyllene (3.1–28.3%), caryophyllene oxide (4.7–31.2%), germacrene D (2.9–22.2%), followed by n-hexacosane, [2Z,6E]-farnesol, eudesma-4(15),7-dien-1-β-ol, α-cadinole, germacrene B, trans-verbenol, and hexanal that were present in some samples in relatively high abundances. The geographic region and the color of capitula were analyzed in correlation with essential oil composition. Also, all investigated species are characterized by the different amount of most dominant components, which leads to the hypothesis that they “choose” different strategies: different combination and amounts of attractants for pollinators. Ecological correlations and taxonomical implications are further discussed., This work was supported by Serbian Ministry of Education, Research and Technological Development (Grant No. 173029).

Comparative micromorphological analyses were conducted on five members of the Xeranthemum group, both perennial (Amphoricarpos exsul and Shangwua masarica) and annual (Chardinia orientalis, Siebera pungens and Xeranthemum inapertum), using scanning electron microscopy (SEM) and SEM coupled with an energy-dispersive spectrometer (SEM-EDS) in order to evaluate whether micromorphological characters correlate with current phylogenies. “Puzzle-like” epidermal cells at the adaxial leaf surface with smooth outer periclinal walls and slightly sinuate anticlinal walls, and lack of weddellite crystals on the involucral bracts are shared by A. exsul and Sh. masarica and Sh. denticulata, while sinuate anticlinal adaxial leaf epidermal cell walls, weddellite crystals on the involucral bracts and an aristate-paleaceous pappus link together Ch. orientalis, S. pungens and X. inapertum. The following traits are probably species-specific: a glabrous adaxial leaf epidermis and cypsela surface, and a plumose-setose pappus in Sh. masarica; a barbate-aristate pappus in A. exsul; irregular shape of cells of the adaxial leaf epidermis with cuticular corrugations, and a papillose cypsela surface in Ch. orientalis; channeled anticlinal borders of adaxial leaf epidermal cells, and wax deposition on the surface of involucral bracts in X. inapertum; and strongly ribbed thickenings of outer periclinal adaxial leaf epidermal cell walls and involucral bracts with a whitish patch of appressed trichomes on their central surface in S. pungens. All of the examined species exhibit vermiform trichomes on the stems and on the abaxial leaf surfaces, adaxial detachment area of cypselae, an asymmetrical carpopodium and direct insertion of the pappus to the pericarp. Our results revealed valuable qualitative characters that facilitate species identification and contribute to a better understanding of relationships between genera. Optimization of these traits onto phylogenetic analyses suggests that some characters found on leaves and involucral bracts are likely due to adaptations of perennial ancestors to xeric habitats., Financial assistance was provided by the Ministry of Education, Science and Technological Development of the Republic of Serbia (Project No. 173029).

The aim of the study was to investigate the chemical composition of Hyssopus officinalis L subsp. pilifer (Pant.) Murb. essential oil (EO) and deodorized extracts (DE) and to evaluate their potential antifungal and antioxidant activities. EO was analyzed by GC-FID and GC-MS. Among the 30 compounds identified in the oil, the main were 1.8-cineole (36.43%), beta-pinene (19.55%), isopinocamphone (15.32%) and trans-pinocamphone (6.39%). Deodorized aqueous extract (DAE) was analyzed by LC-DAD/ESI-TOF MS. The most significant phenolic acids detected in DAE were syringic, caffeoylqunic acids, feruloylquinic and rosmarinic acid. Aspergillus niger, A. ochraceus, A. versicolor, A. fumigatus, Cladosporium cladosporioides, C. fulvum, Penicillium funiculosum, P. ochrochloron, Trichoderma viride and Candida albicans yeast were used for antifungal assay. Minimum inhibitory concentrations (MICs) and minimum fungicidal concentrations (MFCs) of the tested EO and DEs were recorded by the microdilution method. The antioxidant potential of the extracts was evaluated by means of the 2,2-diphenyl-1-picrylhydrazil (DPPH) radical scavenging method. The deodorized aqueous extract (DAE) possessed the highest scavenging activity (EC50=0.54 mg/ml) followed by the deodorized methanol extract (DME) (EC50=0.82 mg/ml) and deodorized ethyl acetate extract (DEE) (EC50 = 2.97 mg/ml). EC/possessed the lowest activities compared to other extracts and control substances. Total phenolic content of DEs was determined by Folin-Ciocalteau (FC) assay and gallic acid was used as the standard. DAE of H. officinalis subsp. pilifer exhibited the highest phenolic content 96.47 GAE. (C) 2013 Elsevier B.V. All rights reserved. Ministry of Education, Science and Technological Development of the Republic of Serbia [173029, 173032, 172053]