Branislava Lakušić

Essential oil and its systematic significance in species of Micromeria Bentham from Serbia & Montenegro

The composition and quantity of the essential oil of Micromeria allowed us to clearly distinguish between sections Pseudomelissa and Eumicromeria. According to our results the species of section Pseudomelissa (M. thymifolia, M. albanica, M. dalmatica and M. pulegium) contained a large quantity of oil (>0.5%) dominated by oxygenated monoterpenes of the menthane type, while the species of section Eumicromeria (M. croatica, M. juliana, M. cristata and M. parviflora) had a small quantity of essential oil (<0.5%) dominated by various terpene compounds. 0.5% of essential oil is defined like boundary value on the basis of the lowest quantity of essential oil measured in populations of species of section Pseudomelissa.

Environment-related variations of the composition of the essential oils of rosemary (Rosmarinus officinalis L.) in the Balkan Penninsula.

Composition of the essential oils of Rosmarinus officinalis of ten populations from the Balkan Peninsula were determined by GC/FID and GC/MS. The main constituents were 1,8‐cineole, camphor, α‐pinene, and borneol. Multivariate statistical analysis (UPGMA cluster analysis and principal‐component analysis (PCA)) revealed two major types of rosemary oil, i.e., 1,8‐cineole and camphor‐type, and two intermediate types, i.e., camphor/1,8‐cineole/borneol type and 1,8‐cineole/camphor type. The regression analyses (simple linear regression and stepwise multiple regression) have shown that, with respect to basic geographic, orographic, and 19 bioclimatic characteristics of each population, bioclimatic factor temperature of habitat represented the dominant abiogenetic factor, which, in chemical sense, led to differentiation of populations in the studied region. Also, the regression analysis have shown that some constituents of essential oils are independent of any single bioclimatic factors. However, some constituents display statistically significant correlations with some abiotic factors.

Antioxidant activity of yellow dock (Rumex crispus L., Polygonaceae) fruit extract

The methanol extract of ripe Rumex crispus L. fruits was evaluated for its antioxidant potential by assays for ferric‐reducing antioxidant power (FRAP), DPPH‐free radical scavenging activity (DPPH) and the influence on lipid peroxidation in liposomes (LP). Considerable activity was observed in all test systems (FRAP: 9.9 mmol Fe2+/g; DPPH IC50: 3.7 μg/mL; LP IC50: 4.9 μg/mL), comparable to that of BHT (FRAP: 8.0 μg/mL; DPPH IC50: 19.4 μg/mL; LP IC50: 3.5 μg/mL), but lower than the activity of ascorbic acid, rutin and quercetin, used as positive control substances. The in vivo effects were evaluated in several hepatic antioxidant systems (activities of LPx, GSH‐Px, Px, CAT and XOD, as well as GSH content), after treatment with the studied yellow dock extract in different doses, or in combination with carbon tetrachloride (CCl4). Pretreatment with the R. crispus extract inhibited CCl4‐induced oxidative stress by decreasing LPx and increasing GSH content in a dose dependent manner, bringing the levels of antioxidant enzymes to near control values. Copyright

Environmental and Seasonal Impacts on the Chemical Composition of Satureja horvatii Silic¤ (Lamiaceae) Essential Oils

The chemical composition of the essential oils of Satureja horvatii Šilić from two natural habitats (Mt. Orjen and Mt. Lovćen in Montenegro) and from cultivated plants (Belgrade, Serbia) were characterized. For the latter, plants from the locus classicus, i.e., Orjenske Lokve (Mt. Orjen), were transferred to Belgrade and, after three years of cultivation, the chemical composition of their essential oils at different phenological stages was analyzed. The essential oils were obtained from the aerial parts of the plants by hydrodistillation and analyzed by GC and GC/MS. The yields and chemical compositions of the S. horvatii oils showed significant differences between the plants collected in the natural habitats and those from cultivation, as well as between the plants at different phenological stages. In the populations from the natural habitats, growing in Mediterranean conditions, the most abundant oil constituents were the phenols thymol (63.7% in the samples from Mt. Orjen) or carvacrol (68.1% in the samples from Mt. Lovćen), while the oils from the cultivated plants (Belgrade), growing in continental conditions, were dominated by linalool (up to 65.8 and 55.9% in average). The basic characteristics of the essential oil from plants at the early phenological stage (before flowering) were high percentages of linalool (37.4%), thymol (27.3%), and carvacrol (12.2%). At the stage of flowering, the percentage of linalool (56.6–57.5%) increased, while those of thymol (15.5–15.8%) and carvacrol (1.4–1.5%) significantly decreased. The essential oil of plants in the full stage of fruiting was characterized by the domination of linalool (58.4 and 65.8%) and lower percentages of thymol (7.6 and 1.3%) and carvacrol (0.7 and 0.1%). In conclusion, the oil composition of S. horvatii was found to depend on the pedoclimatic conditions of the habitat and the phenological stage of the plants.

Variability of the Root Essential Oils of Seseli rigidum Waldst. & Kit. (Apiaceae) from Different Populations in Serbia

The chemical compositions of the essential oils of seven natural populations of Seseli rigidum were analyzed. The essential‐oil yield ranged from 0.16 to 2.09%. Analysis of variance (ANOVA) revealed that there were no statistically significant differences in the mean essential‐oil yields between the populations, and no significant influence of the climate or soil type on the oil yield was observed. In all 67 analyzed samples, the polyacetylene falcarinol was the main compound, followed by octanal, methyl linoleate, α‐muurolene, 3‐butylphthalide, falcarinone, muurola‐4,10(14)‐dien‐1β‐ol, β‐sesquiphellandrene, salvial‐4(14)‐en‐1‐one, δ‐amorphene, spathulenol, and isospathulenol. The principal component analysis (PCA), the canonical discriminant analysis (CDA), and the cluster analysis (CA) revealed differentiation between the populations based on the climate. Three groups of populations were formed; the first group was composed of samples growing in regions with a humid climate, with oils having high falcarinol and low sesquiterpene contents, and the second and third groups comprised samples exposed to semi‐arid climate, with oils characterized by a lower falcarinol and higher α‐muurolene, δ‐amorphene, β‐sesquiphellandrene, and salvial‐4(14)‐en‐1‐one contents. The semi‐arid populations were divided into two groups, which were distinguished based on the oil contents of sesquiterpenes, falcarinone, and 3‐butylphthalide. On the other hand, no clear separation between populations based on the different soil types could be observed.

Chemical Composition and Antimicrobial Activity of the Essential Oil and Methanol Extract of Hypericum aegypticum subsp. webbii (Spach) N. Robson

Hypericum aegypticum subsp. webbii is an evergreen shrub spread in Mediterranean part of central and southeastern Europe. The chemical composition and antimicrobial activity of the essential oil and MeOH extract of H. aegypticum subsp. webbii were investigated. The monoterpenes α‐pinene (63.4 – 68.5%) and β‐pinene (16.9 – 17.0%) were main compounds in the volatile oil from aerial parts. In the cluster analysis, the essential oil of H. aegypticum subsp. webbii was separated and chemically different from the oil of other subspecies of H. aegypticum as well as other Hypericum species from Greece. SIMPER analysis revealed that α‐pinene (24.79%) was the component that contributed the most to differences between all oils. Also, there was extremely high overall dissimilarity between three subspecies of H. aegypticum. MeOH extract of aerial parts of H. aegypticum subsp. webbii contained flavonoids rutin (56.4 ± 0.9 mg/g), hyperoside and quercetin, and phenolic acids chlorogenic and caffeic acid, while naphthodianthrones were not detected. The antimicrobial activity of essential oil was moderate (MIC from 100 to >200 μg/ml), while MeOH extract inhibited the growth of Gram‐positive bacteria Bacillus subtilis, Enterococcus faecalis, Staphylococcus epidermidis, and Micrococcus luteus (MIC 50 – 100 μg/ml), more pronounced than the extract of H. perforatum (MIC 200 – >200 μg/ml).

Composition and Antimicrobial Activity of the Rhizome Essential Oils of Two Athamanta turbith Subspecies

Abstract The hydrodistilled essential oils of the rhizomes of Athamanta turbith subsp. hungarica and A. turbith subsp. haynaldii were analyzed by GC-FID and GC/MS. Twenty-one compounds (99.8% of total oil) were identified in the oil from A. turbith subsp. hungarica, and 33 components (99.9% of total oil) were identified in the oil from A. turbith subsp. haynaldii. Both oils were characterized by high amounts of phenylpropanes, with myristicin (54.2% and 22.3%, respectively) and apiole (32.6% and 48.5%, respectively) being the main components. The antimicrobial activity of the oils was determined using the agar diffusion and broth microdilution method. Investigated essential oils were the most effective against Micrococcus luteus and Klebsiella pneumoniae, and had no effect against Pseudomonas aeruginosa. As for antifungal activity, essential oils exerted similar and significant activity, but only in higher concentrations.

Chemical composition of the essential oil of Thymus bracteosus vis. ex Bentham (Lamiaceae)

Abstract The oil composition of Thymus bracteosus Vis. ex Bentham, collected from Montenegro, was analyzed by GC and GC/MS. The oil yield was 0.15%. Twenty-seven components were identifed. Terpene hydrocarbons were dominant in the oil (68.5%). The main constituents of the oil were germacrene D (15.5%), β-caryophyllene (14.6%), p-cymene (10.2%) and α-pinene (7.2%).

Essential oil composition of different parts of endemic species Seseli gracile Waldst. & Kit. (Apiaceae) from natural and cultivated conditions

The chemical composition of the essential oils of Seseli gracile Waldst. & Kit. from natural habitat (Đerdap gorge, Serbia) and from cultivated plants (Belgrade, Serbia) were characterized. The essential oils of the root, aerial parts, inflorescence and fruit were analyzed by GC/MS and GC/FID. Monoterpene hydrocarbons were the main compounds in the essential oil of aerial parts (45.2-93.0 %), inflorescences (84.1 % and 90.0 %) and fruit (85.0%). Polyacetylenes (38.8% and 87.6 %) were dominant in the essential oil of root. The cluster analysis revealed that there were significant differences in the chemical composition of the S. gracile oils at different phenological stages. On the other hand, essential oils from the aerial parts from natural and cultivated plants showed quite uniform qualitative composition. The aerial parts essential oil from natural habitat contained higher content of para -cymene (mean values 17.3 % vs . 6.5 %) and lower amounts of terpinolene (mean values 23.1 % vs . 49.9 %). Also polyacetylene falcarinol was present only in the aerial parts samples from natural habitat. The essential oil of inflorescences from natural habitat contained higher concentration of terpinolene, quite similar amount of para -cymene and lower content of α-pinene.

Variations in Chemical Composition, Vasorelaxant and Angiotensin I‐Converting Enzyme Inhibitory Activities of Essential Oil from Aerial Parts of Seseli pallasii Besser (Apiaceae)

The present paper describes environmental and seasonal‐related chemical composition variations, vasorelaxant and angiotensin I‐converting enzyme (ACE) activities of essential oil from aerial parts of Seseli pallasii Besser. The composition was analyzed by GC and GC/MS. Monoterpenes were found to be the most abundant chemical class with α‐pinene (42.7 – 48.2%) as the most prevalent component. Seseli pallasi essential oil relaxed isolated endothelium‐intact mesenteric arteries rings precontracted with phenylephrine with IC50 = 3.10 nl/ml (IC50 = 2.70 μg/ml). Also, S. pallasii essential oil was found to exhibit a dose‐dependent ACE inhibitory activity with an IC50 value of 0.33 mg/ml. In silico evaluation of ACE inhibitory activity of the individual components showed that spathulenol exhibited the best binding affinity with ACE, and the lowest binding energy of −7.5 kcal/mol. The results suggested that combination of vasorelaxing and ACE inhibitory effects of the analyzed S. pallasii essential oil might have the potential therapeutic significance in hypertension.