Iris Djordjevic

Effect of four lichen acids isolated from Hypogymnia physodes on viability of rat thymocytes.

Four lichen acids, physodalic acid (F1), physodic acid (F2), 3-hydroxyphysodic acid (F3), and isophysodic acid (F4), were isolated from Hypogymnia physodes methanol extract using preparative reversed-phase high performance liquid chromatography and their structures were determined by UV, MS, (1)H NMR and (13)C NMR. This is the first report on the isolation of F4 from H. physodes. Isolated rat thymocytes were cultivated with increasing F1-F4 concentrations (0.1, 1, 10μg/well) and proliferative activity, viability, ROS (reactive oxygen species) production and MMP (mitochondrial membrane potential) disturbances were evaluated. Obtained results show significantly decreased thymocytes proliferation was observed when cells were treated with F1 (1μg, p<0.05; 10μg; p<0.001), F2 (10μg, p<0.05) and F3 compound (10μg, p<0.05). Significantly increased cytotoxicity was detected when cells were incubated with F1 (1μg, p<0.05; 10μg, p<0.01), F2 (10μg, p<0.05) and F3 compound (10μg, p<0.001). Increased H2DCF-DA fluorescence intensity, when cells were treated with F1 (1μg, p<0.001; 1μg, p<0.01; 10μg, p<0.001) and F2 (1μg, p<0.05; 10μg, p<0.01) compound, indicating the increase of intracellular ROS production. Simultaneously, increased ROS levels were followed with significantly decreased MMP when thymocytes were cultivated with F1 (0.1μg, p<0.001; 1μg, p<0.001; 10μg, p<0.001) and F2 compound (10μg, p<0.001). Thymocytes exposure to increased (0.1, 1, 10μg) concentrations of F3 and F4 compounds did not result with significant alterations in MMP and intracellular ROS production. We have shown that higher F1 and F2 concentrations induce thymocytes toxicity mainly through induction of oxidative stress, while cytotoxicity effect of F3 is followed with altered antioxidant/oxidant balance. The rigid 11H-dibenzo[b,e][1,4]dioxepin-11-one ring in the depsidone structure may play a important role for the examined biological activities.

n-Alkanes in needle waxes of Picea omorika var. vukomanii

Serbian spruce, Picea omorika (Pancic) Purkyne (Pinaceae family), is a relic, endemic, and vulnerable tree species [1], naturaly distributed in fragmented areas in Serbia and Bosnia and Herzegovina [2]. Its variety, (var. vukomanii Pavlovic et Matovic), is represented by a small (up to 30 trees) and geographically isolated natural population in the Milesevka canyon (Serbia). In habitus, branches, and needles, this variety differs clearly from other natural populations of a typical variety of Serbian spruce, Picea omorika var. omorika (syn. var. serbica) [3, 4]. The composition and variability of needle essential oil of Vukoman′s Serbian spruce have been recently investigated [5]. Variability in profile and concentration of n-alkanes are very often used in chemotaxonomic investigations of many conifers and flowering plants [6–15]. The epicuticular wax composition of needles of Serbian spruce and numerous other Picea species have already been studied [16–18], but almost all listed researches dealt with a small number of samples of artificial origin. To the best of our knowledge, this is the first report of the composition and variability of n-alkanes in the needles of P. omorika natural populations. This is also the first report of needle epicuticular wax composition of its variety vukomanii. n-Alkanes in epicuticular waxes of two-year old needles of Vukoman′s Serbian spruce ranged from C18 to C35 (Table 1). The most abundant alkane is C31 (18.58% on average), rarely C29 (14.10% on average). C27 is also present in significant amounts (10.87% on average). The variation of each alkane hydrocarbon is listed as the value of the standard deviation (SD) (Table 1). The most variable alkanes are C33 and C31 (SD values are 16.17 and 10.05, respectively), while the variability of C27 is quite low (SD = 2.64). The carbon preference index values (CPI) of n-alkanes of P. omorika var. vukomanii, calculated by the formula of Bray and Evans, ranged from 0.34 to 4.78 (2.48 on average) (Table 2). Average chain length values (ACL) for all n-alkanes, calculated by the formula of Poynter and Eglington, ranged from 24.80 to 31.18 (27.91 on average) (Table 2). ACLs of n-alkanes with odd carbon numbers show a smaller variation (SD = 1.35) but a higher mean value (29.01) compared to those of even carbon numbers (SD = 1.78, mean value: 26.57). Vukoman′s Serbian spruce has a wider range of carbon numbers of n-alkanes (18–35) than typical Serbian spruce: 19–33 [17] and 18–33 [18]. Vukoman′s Serbian spruce also has a wider range of n-alkane compounds comparing with other Picea species [16–18]. In comparison with literature results [17], Vukoman′s Serbian spruce is more similar to Picea wilsonii from section Eupicea, according to the classification of Krusmann [2], and less similar to the same species, Picea omorika, where only one of these compounds dominated: C31 = 17% after [17] or C33 = 15.7% after [18]. C31 and C29 also dominate in two species from section Casicta (P. yezoenzis and P. likiangensis) [17]. However, in wax needles of P. likiangensis only C31 (53.85%) strongly dominates [18].

Sesquiterpene lactones from Cicerbita alpina

1. Subject and sourceThe roots of Cicerbita alpina (L.) Wallr. were collected from Mt. Komovi, Mon-tenegro. Voucher specimen accession number CAS0799 is deposited in the herbariumat the Faculty of Biology, University of Belgrade—Herbarium Code BEOU.2. Previous workPrevious investigations of the aerial parts of alpine chicory Cicerbita alpina haveshown the presence of insect anti-feedant compounds (Bloszyk, 1988, 1989) and aninsulin-like principle (Schwabe, 1973a, b). From the ethanol extract of the roots, thefuranocoumarins: imperatorin, isoimperatorin, oxypeucedanin and ostruthol and thesesquiterpene lactones: 8-acetyl-15-β-d-glucopyranosyllactucin (1) and 11β,13-dihy-drolactucin (2) were reported by Appendino et al. (1991).

Further Guaianolides from Amphoricarpos neumayeri ssp. murbeckii from Montenegro

The aerial parts of Amphoricarpos neumayeri ssp. murbeckii afforded eleven guaianolides with the same relative (1αH,4β H,5αH,7αH) configuration of the basic skeleton. All of them contained a CH2OX (X = H, acetyl or isovaleroyl) group in 4α-position, typical for amphoricarpolides. Four compounds (1 - 4) were isolated before from the same species, originating from different localities. Guaianolides 5 - 11 are new compounds. Compounds 7 and 8 were epoxidized at the 10α(14)-position. Instead of the Δ11(13)-double bond, observed in all previously isolated guaianolides from the same species, the four lactones contained 11α,13-diol (8 - 10) or 11α-OH,13-chloro (11) moieties respectively.

Intraspecific Variation of Tanacetum larvatum Essential Oil

Abstract The essential oil from aerial parts of Tanacetum larvatum (gris.) Kanitz, an endemic perennial herb collected at three various natural habitats in Montenegro (Planinica [Sample a ], Visitor [Sample b ] and Sinjajevina [Sample c ]), were analyzed using GC and GC/MS. Sixty-four components were identified, representing 83.1%, 96.6% and 89.4% of the total oils content in the Samples a, b and c , respectively. The major constituent in Samples a and b , was oxygenated monoterpene, trans-sabinyl acetate (38.1% and 55.8% respectively). Monoterpene hydrocarbons, β-pinene (13.5%) and santolinatriene (30.6%), were found to be the dominant components in Sample c . The toxic trans-sabinyl acetate was present only in traces in this sample. trans-Chrysanthenyl acetate, as one of major components in feverfew essential oil, has not been previously identified in the investigated essential oils.