COMPOSITIONAL CHARACTERISTICS OF ESSENTIAL OILS OF WILD POPULATIONS OF HYPERICUM PERFORATUM (ST. JOHN’S WORT) FROM LITHUANIA AND FRANCE

Hypericum is a genus of many species that occurs in all temperate parts of the world. Five species of the genus grow wild in Lithuania whereas twenty-eight species of the same genus occur in France. H. perforatum is the most abundant and frequently used as a medical plant and is very significant in pharmacology. Many studies confirmed its antidepressant, antimicrobial, antiviral, anticancer and other activities. Numerous classes of bioactive chemical constituents have been investigated in St. John’s wort, but number of studies on volatile oils is limited. The aim of this study was to evaluate characteristics of volatile oils in various wild populations of H. perforatum from Lithuania and France. Essential oil qualitative and quantitative analyses were performed on aerial parts of H. perforatum collected in different places from Lithuania (2002-2007) and France (2000-2003). The oils were analysed by gas chromatography (FID and capillary columns HP-FFAP and CP Sil) and gas chromatography-mass spectrometry GC-MS (nonpolar cap. column DB-5). Qualitative analysis was based on a comparison of retention times, indices and mass spectra with the corresponding data in the literature and computer mass spectra libraries. A great variability was pointed out between the compositions of the essential oils from the various localities of collection. Even if trans-caryophyllene and its oxide, germacrene D, spathulenol and several aliphatic compounds were the major compounds in all the oils, those from Lithuanian plants were rich in -pinene, while this compound was almost not present in the oils from France. Acknowledgements: Lithuanian Science and Studies Foundation, project “BIOMARKS” (V-08/2008, reg. No. V-08033) in the programme “Gilibert”

Coastal environments shape chemical and microbial properties of forest litters in the Circum-Mediterranean region

This study explores how chemical and microbial properties of litters can be affected by coastal environments across the Mediterranean basin. A litterbag experiment includingPinus halepensisMill. andPistacia lentiscusL., collected from both inland and coastal areas, was set up in France, Greece and Algeria. Control litterbags were left in their sampling sites and a transfer of litterbags from inland to coastal areas was performed to test whether the effect of the specific constraints of coastal environments varies according to the country and the litter type. After 10 months, litter chemical composition (CP/MAS(13)C-NMR) and microbial activities (cellulase activity, basal respiration, catabolic diversity using Biolog) and community structure (TRFLP) were analysed. Coastal conditions led to various responses: (i) litter aromaticity differed in the coastal zones depending on the country (high in the Greek coastal area, low in the Algerian coastal zone), (ii) fewer functionally diversified microbial communities were found in the Greek coastal area compared to the French and Algerian coasts, (iii) genetic diversity and richness were strongly impacted after transfer to the coastal zone whatever the country. The type of litter shaped microbial communities: (i) at a local scale (i.e., in either coastal or inland areas) catabolic profiles and cellulase activities varied with the plant species, (ii) at a regional scale, the effect of coastal conditions differed with the plant species (basal respiration, Shannon-Weaver index, catabolic diversity H ', cellulases and catabolic profiles). Thus, litter microbial properties differed in coastal environments across the Mediterranean basin and plant litter type plays a major role in microbial properties at a large spatial scale. Highlights The environmental drivers of litter microbial sensitivity to water potential stress were investigated Litterbag transfers from inland to coastal areas were performed in the Mediterranean. Soil and land system units conform to long-tail or heavy tail distributions. Microbial diversity of inland litters decreased when exposed to coastal conditions Litter plant species shape microbial functioning even at wide spatial scales. Coastal areas and plant litter drive microbial responses to water potential stress

As, Pb, Sb, and Zn transfer from soil to root of wild rosemary: do native symbionts matter?

International audienceThis is an in natura study aimed to determine the potential of Rosmarinus officinalis for phytostabilization of trace metal and metalloid (TMM)-contaminated soils in the Calanques National Park (Marseille, southeast of France). The link between rosemary tolerance/accumulation of As, Pb, Sb, and Zn and root symbioses with arbuscular mycorrhizal (AM) fungi and/or dark septate endophytes (DSE) was examined. Eight sites along a gradient of contamination were selected for soil and root collections. TMM concentrations were analyzed in all the samples and root symbioses were observed. Moreover, in the roots of various diameters collected in the most contaminated site, X-ray microfluorescence methods were used to determine TMM localization in tissues. Rosemary accumulated, in its roots, the most labile TMM fraction in the soil. The positive linear correlation between TMM concentrations in soil and endophyte root colonization rates suggests the involvement of AM fungi and DSE in rosemary tolerance to TMM. Moreover, a typical TMM localization in root peripheral tissues of thin roots containing endophytes forming AM and DSE development was observed using X-ray microfluorescence. Rosemary and its root symbioses appeared as a potential candidate for a phytostabilization process of metal-contaminated soils in Mediterranean area