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This paper presents new data for secondary metabolites and biological activity of the insufficiently studied European inland halophytes as remarkable indicators of Balkan saline habitats. Phenolic content, flavonoid concentrations and antioxidant activity were analyzed in fifteen terrestrial salt tolerant plants collected from eight saline habitats situated in two distinct semiarid regions of Serbia. Total phenols ranged from 31.86 to 212.71 mg of GA/g of extract (gallic acid equivalent – milligrams of gallic acid per gram of extract). Concentration of flavonoids ranged from 41.21 to 146.06 mg of RU/g of extract (rutin equivalent – milligrams of rutin per gram of extract). Antioxidant activity was determined using 1,1-diphenyl-2-picrylhydrazyl radical reagent; obtained values was ranged from 1785.81 to 17.55 μg/ml. A significant relation was noticed between the concentration of phenols and antioxidant activity. Parallel to the analysis of researched halophytes, Camellia sinensis and Ginkgo biloba were analyzed for comparison. The best antioxidant properties were determined for Statice gmelinii , Artemisia santonicum and Mentha pulegium . The results indicate a potential of studied halophytic species as candidates for natural sources of secondary metabolites with high biological activity, whereas their bioactive compounds might have a significant role in adaptations to salt and drought stress. [ABSTRACT FROM AUTHOR]

Abstract: Phytochemical analyses of the cultivated Sideritis raeseri subsp. raeseri in four different stages of flower development were performed. Traditionally used infusion and decoction were also prepared from aerial parts in full flowering stage, and analyses of active compounds and radical scavenging capacity were performed. The highest yield of the essential oil, obtained by hydrodistillation, was noticed in the full flowering phase (0.11%), with sesquiterpene bicyclogermacrene as the main constituent (42.5%). All examined extracts contained phenolic compounds and their amounts varied from 15.3 to 34.1mgGAE/gDW. The amounts of total phenolics in infusion and decoction were similar (46.5 and 43.9mgGAE/100ml, respectively). LC–ESI-MS analyses of all samples allowed the characterisation of 22 phenolic compounds. Two dominant flavone glycosides, 4′-O-methylhypolaetin-7-O-[6‴-O-acetyl-β-d-allopyranosyl (1→2)-β-d-glucopyranoside (17) and 4′-O-methylisoscutellarein-7-O-[6‴-O-acetyl-β-d-allopyranosyl-(1→2)]-β-d-glucopyranoside (19) were quantified using HPLC. Moreover, the mineral content and the percent of transportation were investigated. [ABSTRACT FROM AUTHOR]