Ivan Šoštarić

Essential Oil Polymorphism of Thymus pannonicus All. (Lamiaceae) in Serbia

Abstract Three populations of Thymus pannonicus grown in Serbia (one from northern and two from east Serbia) were examined for chemical composition of their essential oil. Thymus pannonicus is used in traditional medicine and it is collected by local people in the studied regions, hence the interest in composition of its essential oils. Three major groups of essential oil components were identified, such as monoterpene hydrocarbons, oxygenated monoterpene hydrocarbons and sesquiterpene hydrocarbons. Each of investigated populations showed its own chemotype, including: geranial (citral), α-pinene and germacrene-D. To best of our knowledge, this sesquiterpene hydrocarbon was reported as a major component in Thymus bracteosus only. In these populations the phenolic compounds thymol and carvacrol, considered as most frequent constituents of essential oil in Thymus taxa, haven’t been found in significant quantities.

Genetic Diversity and Demographic History of Wild and Cultivated/Naturalised Plant Populations: Evidence from Dalmatian Sage (Salvia officinalis L., Lamiaceae)

Dalmatian sage (Salvia officinalis L., Lamiaceae) is a well-known aromatic and medicinal Mediterranean plant that is native in coastal regions of the western Balkan and southern Apennine Peninsulas and is commonly cultivated worldwide. It is widely used in the food, pharmaceutical and cosmetic industries. Knowledge of its genetic diversity and spatiotemporal patterns is important for plant breeding programmes and conservation. We used eight microsatellite markers to investigate evolutionary history of indigenous populations as well as genetic diversity and structure within and among indigenous and cultivated/naturalised populations distributed across the Balkan Peninsula. The results showed a clear separation between the indigenous and cultivated/naturalised groups, with the cultivated material originating from one restricted geographical area. Most of the genetic diversity in both groups was attributable to differences among individuals within populations, although spatial genetic analysis of indigenous populations indicated the existence of isolation by distance. Geographical structuring of indigenous populations was found using clustering analysis, with three sub-clusters of indigenous populations. The highest level of gene diversity and the greatest number of private alleles were found in the central part of the eastern Adriatic coast, while decreases in gene diversity and number of private alleles were evident towards the northwestern Adriatic coast and southern and eastern regions of the Balkan Peninsula. The results of Ecological Niche Modelling during Last Glacial Maximum and Approximate Bayesian Computation suggested two plausible evolutionary trajectories: 1) the species survived in the glacial refugium in southern Adriatic coastal region with subsequent colonization events towards northern, eastern and southern Balkan Peninsula; 2) species survived in several refugia exhibiting concurrent divergence into three genetic groups. The insight into genetic diversity and structure also provide the baseline data for conservation of S. officinalis genetic resources valuable for future breeding programmes.

A chemometrics as a powerful tool in the elucidation of the role of metals in the biosynthesis of volatile organic compounds in Hungarian thyme samples.

The volatile fraction of the leaves of Thymus pannonicus All. (Lamiaceae) was analyzed by headspace extraction followed by GC-FID and GC-MS analysis. The different headspace profiles were recognized, with citral and with monoterpene hydrocarbons as dominant compounds. In addition, the determination of Cr, Co, Ni, Mo, Cu, Zn, Mn, Fe, Mg, Ca, K and Na was conducted by spectroscopic techniques (FAAS, GFAAS and ICP-OES). In order to evaluate the relationship between volatile organic compounds and metals, a chemometrics approach was applied. The data obtained by analysis of the headspace and elemental content were subjected to correlation analysis, factor analysis, principal component analysis and cluster analysis. A number of significant correlations of metals with plant volatiles were found. Correlation of Zn with citral, Mn with oxygenated monoterpenes and Mg with β-bourbonene, could be explained by involvement of metals in the biosynthesis of volatile organic compounds.

Essential Oil Composition of Achillea millefolium agg. Populations Collected from Saline Habitats in Serbia

Abstract: Essential oil yield and composition of three populations of yarrow (Achillea millefolium aggregate) occurring on saline habitats of Serbia was analyzed in relation to its soil site characteristics. The total of 99 compounds of essential oils was determined within three estimated chemotypes: the chamazulene + trans-caryophyllene+β-pinene (in population assigned as P1), the lavandulyl acetate+chamazulene + trans-caryophyllene (in P2) and the trans-chrysanthenyl acetate+trans-caryophyllene+germacrene D (in P3). The highest yield of 1.01 % and the lowest of 0.32 % were determined for populations P1 and P3, respectively. The highest total salt content, corresponding with the highest values of ECe and sodium, chloride and sulfate ion concentration was determined for soil of P1 population, which was assessed as solonchak soil, in difference to much lower value of sodium ions, total salts, ECe and pH, all increasing with the soil depth, as determined for samples of P2 and P3 yarrow populations - typical for the solonetz type of salt affected soils. Differences in yield and chemical composition of essential oils were discussed in term of impact of both populations genetic variability and specific environmental conditions. The essential oil quality in all researched yarrow populations accomplishes standards of EU Pharmacopeia 6.0 and thus, sustainable wild collection of yarrow from halophytic habitats could be recommended.