Marjan Niketić

Evaluation of Tanacetum larvatum for an anti-inflammatory activity and for the protection against indomethacin-induced ulcerogenesis in rats

Oral administration of the chloroform extract from Tanacetum larvatum (Griseb. ex Pant.) Kanitz caused a dose-dependent anti-inflammatory effect in the carrageenan-induced rat paw oedema test. The obtained anti-inflammatory effect was 8.6, 32.8, 37.0 and 49.5% for the extract doses of 25, 50, 100 and 200mg/kg, respectively, being statistically significant at a dose of 50mg/kg. Indomethacin had a strong anti-inflammatory effect of 73.4% at a dose of 8mg/kg, but large gastric lesions were detected. When the plant extract in the highest tested dose (200mg/kg) was concomitantly given with indomethacin, the anti-inflammatory effect was slightly enhanced, but the gastric lesions were significantly reduced. The anti-inflammatory and anti-ulcer activity may be mainly due to the inhibition of DNA binding of the transcription factor NF-kappaB by components of the plant extract. This was proven in an electrophoretic mobility shift assay at a concentration of 50microg/ml. Due to its anti-inflammatory as well as anti-ulcer effects, Tanacetum larvatum should especially be used combined with those drugs that are known both for their strong anti-inflammatory activities and the ulcerogenic side effects such as NSAIDs.

Escaping to the summits: phylogeography and predicted range dynamics of Cerastium dinaricum, an endangered high mountain plant endemic to the western Balkan Peninsula.

The Balkans are a major European biodiversity hotspot, however, almost nothing is known about processes of intraspecific diversification of the regions high-altitude biota and their reaction to the predicted global warming. To fill this gap, genome size measurements, AFLP fingerprints, plastid and nuclear sequences were employed to explore the phylogeography of Cerastium dinaricum. Range size changes under future climatic conditions were predicted by niche-based modeling. Likely the most cold-adapted plant endemic to the Dinaric Mountains in the western Balkan Peninsula, the species has conservation priority in the European Union as its highly fragmented distribution range includes only few small populations. A deep phylogeographic split paralleled by divergent genome size separates the populations into two vicariant groups. Substructure is pronounced within the southeastern group, corresponding to the areas higher geographic complexity. Cerastium dinaricum likely responded to past climatic oscillations with altitudinal range shifts, which, coupled with high topographic complexity of the region and warmer climate in the Holocene, sculptured its present fragmented distribution. Field observations revealed that the species is rarer than previously assumed and, as shown by modeling, severely endangered by global warming as viable habitat was predicted to be reduced by more than 70% by the year 2080.

Antimicrobial and antioxidant properties of methanol extracts of two Athamanta turbith subspecies

The methanol extracts of fruits and leaves of Athamanta turbith subsp. hungarica (Borbás) Tutin (Umbelliferae) and A. turbith subsp. haynaldii (Borbás & Uechtr.) Tutin were analyzed for their antimicrobial and antioxidant properties. Phenolic compounds (flavonoids and phenolic acids) of the extracts were examined using HPLC. All the extracts were characterized by the presence of caffeic acid derivates, luteolin and its glycosides, with luteolin 7-O-glucoside as one of the main compounds. Luteolin 7-O-rutinoside was detected only in A. turbith subsp. haynaldii extracts. Investigation of antimicrobial activity was performed against six bacteria and two fungal strains, using the agar diffusion technique and broth microdilution assay. The extracts of investigated A. turbith subspecies exerted similar antimicrobial activity, whereas the best activity was detected against Candida albicans. In order to investigate antioxidant properties, ferric ion reducing antioxidant power (FRAP), radical scavenging capacity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radical (HO·), and the effect on lipid peroxidation (LP) were examined. All the examined extracts showed moderate antioxidant capacity, whereas the fruit extracts were more active than the extracts of leaves. Also, the extracts of A. turbith subsp. hungarica exerted higher antioxidant capacity than corresponding A. turbith subsp. haynaldii extracts. The relationship between estimated activity and chemical composition of the extracts is discussed.

Sesquiterpene lactones from the extracts of two Balkan endemic Laserpitium species and their cytotoxic activity

Chloroform extracts of the underground parts of two Balkan endemic Laserpitium species, Laserpitium zernyi Hayek and Laserpitium ochridanum Micevski, were chemically investigated. Five unknown guaianolides from the class of slovanolides, of which four were additionally 2β-esterified, as well as two lactones, previously identified in other Laserpitium species, were isolated from the L. ochridanum extract. From the L. zernyi extract one slovanolide derivative was isolated for the first time in the genus Laserpitium. In addition, the phenylpropanoid latifolone and six known sesquiterpene lactones, characterised as derivatives of slovanolide and silerolide, were isolated from the extracts of both species. The cytotoxic activities of the total extracts and the isolated compounds were tested using MTT and SRB assays on the two human breast cancer cell lines, MCF 7/6 and MCF 7/AZ. The extracts exerted cytotoxic activities with the IC(50) values ranging 65.21-348.25 μg/mL. The L. ochridanum extract was most potent in the MTT test with IC(50) values of 65.21 and 66.09 μg/mL in the MCF 7/AZ and MCF 7/6 cell lines, respectively. The highest cytotoxic activity exerted 2β,8α-di-angeloyloxy-10β-hydroxy-6αH-guaian-3,(7-11)-dien-12,6-olide, a slovanolide derivative with an additional double bond in lactone ring, on highly invasive MCF 7/6 cell line, with IC(50) value 0.7 μM in both assays tested. Generally, guaianolides with a higher number of ester moieties at the positions 2β, 8α, 10β or 11α exhibited IC(50) values in the micromolar range, while eudesmanolides and guaianolides with a lower number of esters did not induce significant cytotoxicity.

The antiinflammatory, gastroprotective and antioxidant activities of Hieracium gymnocephalum extract

The present study investigated the antiinflammatory, gastroprotective and antioxidant activities of a CH2Cl2 extract of western Balkan endemic Hieracium gymnocephalum Griseb. ex Pant. (Compositae). The carrageenan‐induced rat paw oedema test was used as an experimental model for screening the antiinflammatory activity. The extract was administrated p.o. in doses of 25, 50, 100 and 200 mg/kg to rats and its effects compared with indomethacin, used p.o. as a reference drug. The results showed that the investigated extract reduced the oedema in a concentration‐dependent manner. The obtained antiinflammatory effect was 5.9%, 11.7%, 31.2% and 44.1% at doses of 25, 50, 100 and 200 mg/kg, respectively, being statistically significant at a dose of 100 mg/kg. Indomethacin had a strong antiinflammatory effect of 73.4% at a dose of 8 mg/kg, but caused large gastric lesions. When the plant extract in the highest tested dose (200 mg/kg) was concomitantly given with indomethacin, the antiinflammatory effect was slightly enhanced, but the gastric lesions were significantly reduced. The antioxidant activity of the H. gymnocephalum extract, investigated using DPPH radical assay, OH‐radical assay and TBA‐test, was not substantial. Copyright

Composition, antimicrobial and antioxidant activity of the extracts of Eryngium palmatum Pančić and Vis. (Apiaceae)

The chemical composition, antimicrobial and antioxidant activity of Eryngium palmatum, an endemic plant species from the Balkan Peninsula, were investigated. The flavonoids apigenin (9.5±0.3 mg g−1) and apigenin 7-O-glucoside (2.4±0.1 mg g−1) were determined in a methanol extract of aerial parts using HPLC analysis. The methanol extract of roots contained catechin (5.0±0.1 mg g−1), epicatechin (2.9±0.1 mg g−1), chlorogenic acid (1.6±0.0 mg g−1), gallic acid (0.9±0.0 mg g−1) and rosmarinic acid (0.9±0.2 mg g−1). GC-FID and GCMS analysis of a chloroform extract of aerial parts showed that the main volatile constituents were falcarinol, linoleic acid, hexadecanoic acid and methyl linoleate (comprising 32.6%; 24.4%; 19.9; 13.2% of the volatile fraction, respectively), while octanoic acid, tetradecanol and dodecanol dominated in the chloroform extract of the roots (34.9%; 25.8%; 22.2% of the volatile fraction, respectively). Investigation of antimicrobial activity by broth microdilution showed that the methanol and chloroform extracts of aerial parts and roots exerted a significant effect (MIC 3.5–15.6 μg mL−1) against tested Gram-positive and Gram-negative bacteria. The methanol extracts of aerial parts or roots exerted moderate ferric reducing antioxidant power, DPPH radical scavenging activity and hydroxyl radical scavenging activity.

Trace Metals in Soils and Several Brassicaceae Plant Species from Serpentine Sites of Serbia

Abstract Serpentine soils from 16 sample points in Serbia as well as the roots and shoots of eight Brassicaceae family species: Aethionema saxatile, Alyssum montanum, Alyssum repens, Cardamine plumieri, Erysimum linariifolium, Erysimum carniolicum, Isatis tinctoria, Rorippa lippizensis, were analyzed with regard to their concentrations of P, K, Fe, Ca, Mg, Ni, Zn, Mn, Cu, Cr, Cd, and Pb. Most of the soil samples were typical of ultramafic sites with low concentrations of P, K and Ca and high concentrations of Mg, Fe, Ni and Zn. Ca/Mg ratio was <1 in most soil samples and Brassicaceae plants. Only in A. montanum, A. repens, E. linariifolium and R. lippizensis was the Ca/Mg ratio >1. The levels of P, K, Fe and Zn were high, Mn and Cu occurred in low amounts, whereas Cr, Cd, Co and Pb were only traceable. In the roots and shoots of A. montanum and A. repens the measured concentrations of Ni were 657 mg kg-1 and 676 mg kg-1 respectively, which is the first instance that such high concentrations of Ni were detected in these two species.

Composition and antimicrobial activity of the essential oils of Laserpitium latifolium L. and L. ochridanum Micevski (Apiaceae).

The chemical composition and antimicrobial activity of essential oils of Laserpitium latifolium and L. ochridanum were investigated. The essential oils were isolated by steam distillation and characterized by GC‐FID and GC/MS analyses. All essential oils were distinguished by high contents of monoterpenes, and α‐pinene was the most abundant compound in the essential oils of L. latifolium underground parts and fruits (contents of 44.4 and 44.0%, resp.). The fruit essential oil was also rich in sabinene (26.8%). Regarding the L. ochridanum essential oils, the main constituents were limonene in the fruit oil (57.7%) and sabinene in the herb oil (25.9%). The antimicrobial activity of these essential oils as well as that of L. ochridanum underground parts, whose composition was reported previously, was tested by the broth‐microdilution method against four Gram‐positive and three Gram‐negative bacteria and two Candida albicans strains. Except the L. latifolium underground‐parts essential oil, the other investigated oils showed a high antimicrobial potential against Staphylococcus aureus, S. epidermidis, Micrococcus luteus, or Candida albicans (minimal inhibitory concentrations of 13.0–73.0 μg/ml), comparable to or even higher than that of thymol, which was used as reference compound.

Chloroform extract of underground parts of Ferula heuffelii: secondary metabolites and spasmolytic activity.

Plants from the genus Ferula L. (Apiaceae) were used for various purposes in traditional medicine of different nations throughout the history. Ferula heuffelii Griseb. ex Heuffel is a perennial species endemic for Balkan peninsula. Ten compounds which belong to classes of prenyl‐furocoumarin‐, prenyl‐dihydrofurochromone‐, prenyl‐benzoyl‐ and prenyl‐benzoylfuranone‐type sesquiterpenoids, as well as sesquiterpene coumarins and phenylpropanoids, were, for the first time, isolated from the CHCl3 extract of the underground parts of this plant and identified. Furthermore, extract and three isolated compounds, i.e., latifolone (1), dshamirone (4), and (2S*,3R*)‐2‐[(3E)‐4,8‐dimethylnona‐3,7‐dien‐1‐yl]‐2,3‐dihydro‐7‐hydroxy‐2,3‐dimethylfuro[3,2‐c]coumarin (6) were, for the first time, evaluated for their in vitro antispasmodic activities in three experimental models: spontaneous contraction, and ACh‐ and KCl‐induced contraction of an isolated rat ileum. The extract (0.1–1.3 mg/ml) and compound 6 (1–10 μg/ml) exhibited dose‐dependent effect in all three models. Compound 1 (1–6 μg/ml) affected spontaneous contractions and those induced by KCl, while compound 4 (8 μg/ml) displayed only moderate activity with ACh‐induced contractions. It can be concluded that tested compounds contribute to exhibited antispasmodic activity of crude extract. Additionally, extract (0.1–1.3 mg/ml) was tested for in vitro relaxant activity on an isolated rat trachea, and relaxed the KCl‐induced contractions in a dose‐dependent manner.

Composition and Antimicrobial Activity of Salvia amplexicaulis Lam. Essential Oil

Abstract The chemical analysis of the Salvia amplexicaulis Lam. herb essential oil was performed using GC-FID and GC/MS. Fifty-one compounds (90.2% of the total oil) were identified. The oil was characterized by a high amount of sesquiterpenes (81.1%), with germacrene D (14.8%), viridiflorol (10.6%), caryophyllene oxide (10.5%), and β-caryophyllene (9.4%) being the main components. The microbial growth inhibitory properties of the oil was determined against Gram-positive bacteria Staphylococcus aureus, St. epidermidis, Micrococcus luteus Gram-negative bacteria Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli and a yeast Candida albicans. The best inhibitory effect was detected against M. luteus followed by the effects against St. epidermidis, St. aureus and C. albicans. Tested Gram-negative bacteria were more resistant than Gram-positive bacteria and C. albicans.