UDK 577.164.2:582.711.714           535.234:577.164.2 Vitamin C or ascorbic acid content has been determined by spectrophotometric method in fruits of some Bosnian hawthorns (Crataegus L). species. Spectrophotometric method used in this study is based on the kinetic reaction between Vitamin C and methylene blue. Measurements were carried out at absorption maximum, λmax= 665 nm. Titrimetric method was used as the reference method for comparison of the obtained results. We found that the lowest content of vitamin C was 106.12 mg/100 g of a dry sample in fruits of the C. monogyna, and the highest level of Vitamin C was found in the C. microphylla (231.96 mg/100 g of a dry sample) fruits. Recoveries of the results obtained by the spectrophotometric method were 101.4% - 108.0% with relative standard deviation (RSD) values ranging between 0.40% - 3.37%. Obtained results showed that fruits of studied Crataegus L. species are a good source of vitamin C with its potential to be used in food industry as the natural antioxidant.

This study was undertaken in order to evaluate possible antioxidative and antiproliferative activities of three Helleborus taxa. The dry leaves and roots of three Helleborus taxa were extracted with ethanol and water. A phytochemical evaluation of the selected extracts was performed using spectrophotometric methods and a 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity assay was used for measuring the antioxidative activity of extracts. The antiproliferative activity of the three Helleborus taxa was studied using Burkitt's lymphoma B cells (BJAB) cell lines. The phytochemical evaluation showed that the leaves contain high levels of total phenolic and flavonoid content. Results from the DPPH assay indicated that the activity of the ethanol and water extracts of the leaves was higher than that of positive control (thymol). Extracts from the roots of H. odorus also displayed higher antioxidant activity than the positive probe, while H. mulifidus and H. hercegovinus root extracts were less effective. A statistically significant correlation between total phenolic content and antioxidative properties indicates that these compounds contribute to the antioxidant activity. The highest percentage of cell growth inhibition was observed when testing the water root extracts of H. multifidus (50.14%) and H. hercegovinus (49.04%). In contrast, the water leaf extract of H. hercegovinus exhibited the lowest inhibition of cell growth (8.59%), although it showed strong antioxidant activity.

Hydrodistilled essential oil and the corresponding headspace volatiles of Bosnian wild growing Thymus praecox ssp. polytrichus (A. Kern. Ex Borbàs) Jalas and Thymus praecox ssp. skorpilii (Velen.) Jalas were subjected to capillary GC-MS analysis. This work presents a detailed essential oil analysis of these two rare Thymus subspecies from Bosnia, as well as the very first report on their headspace composition. Eighty-seven volatile constituents were identified in four samples. Two alcohols were the major constituents in the essential oil of T. praecox ssp. polytrichus, a monoterpene, linalool (13.9%), and a sesquiterpene, (E)-nerolidol (10.4%), while linalyl acetate (36.7%) and linalool (22.7%) were the most abundant volatiles in the corresponding headspace sample. Oxygenated monoterpenes (57.5%) predominate in the essential oil of T. praecox ssp. skorpilii with linalyl acetate (28.7%) and linalool (14.4%) as the main representatives. Headspace sample of this subspecies also showed richness in linalyl acetate (52.4%), while the second most abundant compound was α-pinene (14.5%), a monoterpene hydrocarbon.

Essential‐oil profile of Salvia brachyodon Vandas, an endemic Dinaric species transferred from Adriatic Coast to the continental climatic conditions, was determined. Hydrodistilled oils obtained from the plant material collected in three‐year field trial were subjected to the detailed GC/MS analysis. Hundred and fifty volatile compounds were identified in four samples. Comparison of the chemical composition of the isolated essential oils showed that population collected one year after transfer preserved sesquiterpene character of its oil (74.3%), while all subsequent samples gave the oils of monoterpene type with 1,8‐cineole as the principal constituent (22.2–42.3%). The high degree of variation in the qualitative and quantitative composition of the volatile constituents revealed the strong influence of environmental conditions on the nature of plant chemical composition that has an important role in a plant adaptation.

Stachys menthifolia Vis. (Lamiaceae) is an endemic species from the Balkan Peninsula spread throughout Albania, Greece, Montenegro, and Croatia. This article presents the first investigation of the essential oil composition of this species from Croatia. Aerial parts of the plant were collected from three different natural habitats in the region of Biokovo Mountain. The studied populations showed similarity in qualitative, but not in quantitative, composition of their essential oils. Hydrodistilled volatile oil obtained from the plant material of S. menthifolia was subjected to gas chromatographic analysis coupled to mass spectrometry. More than 100 compounds were identified in the three samples, representing 86.8–90.8% of the total oil. The terpene profile of S. menthifolia is characterized by a high content of oxygenated sesquiterpenes (48.4–58.9%) and diterpene hydrocarbons (3.5–25.2%), with 8-α-acetoxyelemol (6.9–21.3%), abietatriene (3.5–21.1%), and 4′-methoxyacetophenone (4.5–17.0%) as the main constituents.

Essential oil of Thymus aureopunctatus (Beck) K. Malý, obtained by hydrodistillation and headspace technique, was subjected to capillary GC-MS analysis, and its volatile composition was compared with essential oil profile of Thymus serpyllum L. and a botanically undetermined thyme species, Thymus spp., all growing wild in the same habitat in Bosnia and Herzegovina. This paper presents the first report on phytochemical analysis of the rare T. aureopunctatus species, and also the first report on headspace analysis of plants belonging to the genus Thymus. One hundred and two volatile constituents were identified. The investigated Thymus species of Bosnian origin clearly belong to the thymol-chemotype with relatively abundant level of this main constituent varying from 30.5% for T. serpyllum, and 34.5% for T. aureopunctatus, to 44.2% for Thymus spp., while their corresponding headspace samples contain very high percentage of p-cymene, thymol biosynthesis precursor, in the range from 29.1% to 68.1%.

Abstract Satureja is a genus of the well-known medicinal plants of Lamiaceae family that comprises numerous species growing wild in the Mediterranean area. The essential oils of Satureja visianii Šilic and Satureja montana L., growing together at the same habitat under similar environmental conditions, were subjected to detailed gas chromatography-mass spectrometry analysis in order to compare their chemical composition. S. visianii Šilic is a stenoendemic species with narrow geographical distribution limited to only one locality, Pelješac Peninsula in Croatia. More than one hundred twenty compounds were identified in both plant oils representing 90.4 % - 99.5 % of the total oil. The most abundant components in S. visianii essential oil were viridiflorol (17.9 %), borneol (12.6 %) and camphor (6.5 %), while S. montana oil was rich in phenolic compounds carvacrol (59.1 %) and thymol (20.1 %).

The essential oil and headspace obtained from odorous parts of Thymus moesiacus Velen., an endemic species from Bosnia and Herzegovina, were subjected to capillary GC/MS analysis. The identification of the volatile constituents was accomplished by computer library search, retention indices RI, and the visual interpretation of mass spectra with those found in the literature [1] and in the laboratory own database. Fifty-seven compounds were identified in both samples: fifty-five in essential oil, and thirty-five in headspace sample, representing 99.27% and 99.49%, respectively. The most abundant components in essential oil were gamma-muurolene (24.68%), thymol (8.62%) and bornyl acetate (8.26%), while the main constituents of the headspace sample were p-cymene (18.07%), alpha-pinene (15.34%), and gamma-muurolene (12.91%). Presented results significantly differ from those previously published [2,3], which is in agreement with the fact of complex chemical polymorphism of this genus. References: 1. Adams, R.P. (2001) Identification of Essential oil of Components by Gas Chromatography/Quadrupole Mass Spectroscopy. Allured Publishing Corporation. Illinois. 2. Kulevanova, S. et al. (1996) Planta Med. 62:78–79. 3. Cavar, S. et al. (2006) IV Balkan Botanical Congress, Sofia, Book of Abstracts, p.285.