Centaurea Research Papers - Academia.edu (original) (raw)

Centaurea solstitialis (yellow star thistle) has been proven to cause equine nigropallidal encephalomalacia in horses. Over the last fifty years, nigropallidal encephalomalacia has been of interest to human medicine due to the possible connection with Parkinson's disease. Previous studies indicated the presence of neurotoxic nitrogenous compounds in polar extracts of the plant. In order to give a more detailed description of the nitrogen-containing fraction of C. solstitialis, various samples were collected at different development stages. Different aliquots of the same aqueous extract were directly derivatized with ophthaldialdehyde and dansyl chloride and analyzed separately by reversed-phase HPLC. A complete profile of the free nitrogenous fraction of C. solstitialis was given and results obtained with the two derivatization procedures were compared. No particularly high level of free aspartic and glutamic acids, two potent neuroexcitotoxic amino acids, were found in polar extracts of the plant. Tyramine resulted to be the most important biologically active amine present in C. solstitialis (with a mean concentration of 2.0 mg/100 g of dry weight). q

- by
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- Nitrogen, Neurotoxins, High Pressure Liquid Chromatography, Amino Acids

The methanol and aqueous extracts of three endemic Centaurea species (C. polypodiifolia var. pseudobehen, C. pyrrhoblephara and C. antalyense) were investigated for their antioxidant and cholinesterase inhibitory activities. The antioxidant activities of these extracts were evaluated by in vitro models including, phosphomolybdenum assay, free radical scavenging assays (DPPH and ABTS), b-carotene/linoleic acid test system, metal chelating assay, FRAP assay, ferric and cupric reducing power. Cholinesterase inhibitory activities were examined using Ellman's colorimetric method. Total phenol, flavonoid, and saponin contents were also measured. Among the six Centaurea extracts evaluated, the highest antioxidant abilities were obtained from C. polypodiifolia var. pseudobehen. Methanolic extracts from C. polypodiifolia var. pseudobehen and C. antalyense had a noticeable inhibition towards AChE and BChE. These findings suggest that Centaurea species could be an anticholinesterase agent and antioxidant resource in some industries, such as food, pharmacology, and cosmetics.

- by Gökhan Zengin
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- Water, Antioxidants, Methanol, Cholinesterase inhibitors
- by Soyingbe Oluwagbemiga
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- Pharmacology, Botany, Analytical Chemistry, Organic Chemistry

Two elemanolide sesquiterpenes and two eudesmane-type sesquiterpene glycosides named hierapolitanins A-D, were isolated, together with five known compounds, two flavones; hispidulin and jaceosidin, a flavon-C-glycoside, shaftoside, a flavonol glycoside, kaempferol-3-O-rutinoside and a neolignan, dehydrodiconiferyl alcohol from the aerial parts of Centaurea hierapolitana Boiss. (Asteraceae). Structure elucidations were based on spectroscopic evidence.

- by Rahul Pawar
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- Phytochemistry, Mass Spectrometry, Biological Sciences, Sesquiterpenes

The medical ethnobotanical knowledge propagated over generations in the coastal regions of the Eastern Mediterranean, including Lebanon, is one that has built on several ancient cultures and civilizations of these regions. Recent interest in medical ethnobotany and the use of medicinal herbs in treating or preventing ailments has rejuvenated interest in folk medicine practices, especially those transcendent across generations. According to Eastern Mediterranean folk medicine practices, herbal remedies that treat many inflammation-related ailments were typically based on plant bioactive water extracts or decoctions. Studies have shown that active anti-inflammatory ingredients in water extracts include many natural chemicals such as phenols, alkaloids, glycosides, and carbohydrates. The intent of this manuscript is twofold: first, to review the literature that describes anti-inflammatory bioactivities in plant extracts of different plant genera; and second, to evaluate indigenous folk remedies used by folk doctors to treat inflammatory ailments in this region of the world. For this aim, the reported literature of five plant genera assumed to possess anti-inflammatory bioactivities and typically prescribed by folk doctors to treat inflammation-related ailments is reviewed.

- by Elie Barbour
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- Nutrition and Dietetics, Traditional Medicine, Lebanon, Flavonoids
- by Matthias Hamburger
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- Complementary and Alternative Medicine, Plant Biology, Cell line, Mice

We studied the life history, geographic distribution, behavior, and ecology of Larinus filiformis Petri (Coleoptera: Curculionidae) in its native range to determine whether it is worthy of further evaluation as a classical biological control agent of yellow starthistle, Centaurea solstitialis (Asteraceae: Cardueae). Larinus filiformis occurs in Armenia, Azerbaijan, Turkey, and Bulgaria and has been reared only from C. solstitialis. At Þeld sites in central and eastern Turkey, adults were well synchronized with the plant, being active from mid-May to late July and ovipositing in capitula (ßowerheads) of C. solstitialis from mid-June to mid-July. Larvae destroy all the seeds in a capitulum. The insect is univoltine in Turkey, and adults hibernate from mid-September to mid-May. In the spring, before adults begin ovipositing, they feed on the immature ßower buds of C. solstitialis, causing them to die. The weevil destroyed 25Ð75% of capitula at natural Þeld sites, depending on the sample date. Preliminary host speciÞcity experiments on adult feeding indicate that the weevil seems to be restricted to a relatively small number of plants within the Cardueae. Approximately 57% of larvae or pupae collected late in the summer were parasitized by hymenopterans [Bracon urinator, B. tshitsherini (Braconidae) and Exeristes roborator (Ichneumonidae), Aprostocetus sp. (Eulophidae), and uniden-tiÞed species of Eurytomidae and Ormyridae]. This weevil may be a better choice than the other capitula insects already established in the United States, particularly in colder parts of the plantÕs range.

- by Massimo Cristofaro
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- Zoology, Geography, Life history, Bulgaria

Sesquiterpene lactones are terpenoid compounds characteristic of the Asteraceae (Compositae) possessing a variety of biological activities, such as cytotoxic, antitumor, antibacterial, and antifungal. The prediction of the pharmacokinetic profile of several antifungal sesquiterpene lactones, isolated from Greek taxa of Centaurea sp., was undertaken in this study using the VolSurf procedure. The molecules were projected on the following pre-calculated ADME models: Caco-2 cell permeability, plasma protein affinity, blood-brain barrier permeation and thermodynamic solubility. The in silico projection revealed a non optimal pharmacokinetic profile for the studied compounds. ADME in silico screening of a semisynthetic derivatives virtual library has been performed in order to optimize the pharmacokinetic properties. A number of derivatives were proposed as it was predicted to have higher Caco-2 cell permeability, while the pharmacokinetic behaviour regarding BBB penetration, protein binding and solubility was mainly preserved.

Antioxidant capacities of methanolic extract and fatty acid composition of three Centaurea species were investigated. The antioxidant capacity of the extracts was evaluated by different assays, including total phenolic content, phosphomolybdenum assay, free radical scavenging activity (DPPH assay), b-carotene/linoleic acid bleaching assay, iron (III) and cupric reduction assay. The findings showed that the methanolic extract of Centaurea pulchella has the strongest antioxidant capacity compared to other two Centaurea species. The order of the antioxidant properties of Centaurea species were C. pulchella > C. patula > C. tchihatcheffii. Thirty fatty acids were identified in the oils of three Centaurea species. The major fatty acids of these species were found to be linoleic acid from C. pulchella and C. tchihatcheffii, and a-linolenic acid from C. patula. The study concluded that the Centaurea species can be used as a source of natural antioxidants and essential fatty acids.

- by Yavuz Selim Çakmak
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- Turkey, Composition, Antioxidants, In Vitro

† Background and Aims In a mixed-ploidy population, strong frequency-dependent mating will lead to the elimination of the less common cytotype, unless prezygotic barriers enhance assortative mating. However, such barriers favouring cytotype coexistence have only rarely been explored. Here, an assessment is made of the mechanisms involved in formation of mixed-ploidy populations and coexistence of diploid plants and their closely related allotetraploid derivates from the Centaurea stoebe complex (Asteraceae). † Methods An investigation was made of microspatial and microhabitat distribution, life-history and fitness traits, flowering phenology, genetic relatedness of cytotypes and intercytotype gene flow (cpDNA and microsatellites) in six mixed-ploidy populations in Central Europe. † Key Results Diploids and tetraploids were genetically differentiated, thus corroborating the secondary origin of contact zones. The cytotypes were spatially segregated at all sites studied, with tetraploids colonizing preferentially drier and open microhabitats created by human-induced disturbances. Conversely, they were rare in more natural microsites and microsites with denser vegetation despite their superior persistence ability ( polycarpic life cycle). The seed set of tetraploid plants was strongly influenced by their frequency in mixed-ploidy populations. Triploid hybrids originated from bidirectional hybridizations were extremely rare and almost completely sterile, indicating a strong postzygotic barrier between cytotypes. † Conclusions The findings suggest that tetraploids are later immigrants into already established diploid populations and that anthropogenic activities creating open niches favouring propagule introductions were the major factor shaping the non-random distribution and habitat segregation of cytotypes at fine spatial scale. Establishment and spread of tetraploids was further facilitated by their superior persistence through the perennial life cycle. The results highlight the importance of non-adaptive spatio-temporal processes in explaining microhabitat and microspatial segregation of cytotypes.

- by Olivier Broennimann
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- Phylogeography, Gene Flow, Plant Biology, Ecology

Acclimation of foliage photosynthetic properties occurs with varying time kinetics, but structural, chemical and physiological factors controlling the kinetics of acclimation are poorly understood, especially in field environments. We measured chlorophyll fluorescence characteristics, leaf total carotenoid (Car), chlorophyll (Chl) and nitrogen (N) content and leaf dry mass per area (LMA) along vertical light gradients in natural canopies of the herb species, Inula salicina and Centaurea jacea, and tree species, Populus tremula and Tilia cordata, in the middle of the growing season. Presence of stress was assessed on the basis of night measurements of chlorophyll fluorescence. Our aim was to compare the light acclimation of leaf traits, which respond to light availability at long (LMA and N), medium (Chl a ⁄ b ratio, Car ⁄ Chl ratio) and short time scales (fluorescence characteristics). We found that light acclimation of nitrogen content per unit leaf area (N area ), chlorophyll content per unit dry mass (Chl mass ) and Chl ⁄ N ratio were related to modifications in LMA. The maximum PSII quantum yield (F v ⁄ F m ) increased with increasing growth irradiance in I. salicina and P. tremula but decreased in T. cordata. Leaf growth irradiance, N content and plant species explained the majority of variability in chlorophyll fluorescence characteristics, up to 90% for steady-state fluorescence yield, while the contribution of leaf total carotenoid content was generally not significant. Chlorophyll fluorescence characteristics did not differ strongly between growth forms, but differed among species within a given growth form. These data highlight that foliage acclimation to light is driven by interactions between traits with varying time kinetics.

- by Lea Hallik
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- Photosynthesis, Plant Biology, Fluorescence, Carotenoids

The phytochemical investigation of the aerial parts of Centaurea deflexa led to the identification of 21 compounds, among which three phenolic acids, one sterol, ten flavonoids, one phenylpropanoid derivative, two lignans and four sesquiterpene lactones. One of the latter compounds was a new, rare active principle (1) having an uncommon 15-nor-guaianolide skeleton. The biological investigation was carried out through a bio-guided assay fractionation of C. deflexa extracts and highlighted an anti-proliferative activity of two sesquiterpene lactones, aguerin B and the newly identified 15-nor-guaianolide (1) against human pancreatic and colonic cancer cells. Of the two compounds, only aguerin B showed to induce apoptotic cell death, confirming the role as pro-apoptotic moiety of the a-methylene-g-lactone ring present in aguerin B but not in 1.

- by Guido Flamini
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- Organic Chemistry, Apoptosis, Cell Death, Sesquiterpenes

The antimicrobial and cytotoxic activities of chloroform extracts from the weeds Centaurea tweediei and C. diffusa, and the main sesquiterpene lactones isolated from these species, onopordopicrin and cnicin, respectively, were assayed. Results show that the chloroform extracts from both Centaurea species possess antibacterial activities against a panel of Gram-positive and Gram-negative bacteria. Remarkable antibacterial activity against methicillin-resistant Staphylococcus aureus was also measured. Both the extracts and the purified sesquiterpene lactones show high cytotoxicity against human-derived macrophages. Despite this cytotoxicity, C. diffusa chloroform extract and cnicin are attractive candidates for evaluation as antibiotics in topical preparations against skin-associated pathogens.

- by Cesar Catalan
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- Organic Chemistry, Plant Biology, Cell line, Sesquiterpenes

In this study, composition of essential oil and antioxidant capacity of Centaurea drabifolia subsp. detonsa were investigated. The antioxidant capacity of the methanolic extract was evaluated by various methods including measuring the total phenolic content, total antioxidant capacity, free radical scavenging activity (DPPH assay), β-carotene/linoleic acid bleaching assay and ferric and cupric ion reducing power assay. The composition of essential oil was identified by using gas chromatography–mass spectrometry. Totally, 41 compounds were described in the essential oil. Germacrene D (44.829%) was determined as the major compound of the essential oil. The total phenolic content, total antioxidant capacity, inhibition rate of oxidation of linoleic acid, IC50 (in DPPH assay) and EC50 (in reducing power) value were found to be 40.454 mg GAE/g, 100.840 mg AAE/g, 65.639%, 39.584 µg mL−1 and 0.603 mg mL−1, respectively. The results indicated that the extract of C. drabifolia subsp. detonsa has strong antioxidant properties and this species can be used as a natural antioxidant in food processing and pharmaceutical industries.

- by Yavuz Selim Çakmak
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- Turkey, Multidisciplinary, Food Processing, Pharmaceutical industry

In this study, fatty acid compositions of six Centaurea species growing in the Konya region were determined. The fatty acid composition of Centaurea balsamita, Centaurea calolepis, Centaurea carduiformis subsp. carduiformis, Centaurea cariensis subsp. maculiceps, C. cariensis subsp. microlepis and Centaurea iberica were analysed. Four species of these six Centaurea are endemic to Turkey. The endemic Centaurea species are C. calolepis, C. carduiformis subsp. carduiformis, C. cariensis subsp. maculiceps and C. cariensis subsp. microlepis. Generally, C 18:2 ω6 linoleic acid, C 16:0 palmitic acid, C 18:3 ω3 linolenic acid and C 18:1 oleic acid were found to be the major fatty acids in all species. Polyunsaturated fatty acids (PUFAs) were found in higher amounts than saturated fatty acids and monounsaturated fatty acids in all species. PUFAs were determined at 55.10%, 50.25%, 51.41%, 41.02%, 46.18% and 58.80% in C. balsamita, C. calolepis, C. carduiformis subsp. carduiformis, C. cariensis subsp. maculiceps, C. cariensis subsp. microlepis and C. iberica, respectively.

- by Dimas Ramadan
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- Turkey, Multidisciplinary, Fatty acids, Natural Product

Aim of the study: Several Centaurea species (Asteraceae) are used in Turkish folk medicine to alleviate pain and inflammatory symptoms in rheumatoid arthritis, high fever, head ache and for wound healing. Particularly, the aerial part of Centaurea iberica Trev. ex Spreng. has been practiced on wounds for healing. In order to evaluate the anti-inflammatory and wound healing activities of the plant, extracts were prepared with variety of solvents: hexane, chloroform, ethyl acetate and aqueous methanol (85%) from the aerial parts of Centaurea iberica. Materials and methods: The incision by using tensiometer and excision models were used in order to assess the effect of the plant extracts on wound healing in mice and rats. Results were also evaluated histopathologically. In vivo inhibitory effect of the extracts on acetic acid-induced increase in capillary permeability was studied for the assessment of anti-inflammatory activity. Results: The wound healing effect was comparatively evaluated with a reference ointment Madecassol ® . Noteworthy wound healing activity was observed for the ointment formulation prepared with 1% methanol extract. The results of histopathological evaluation supported the outcome of both incision and excision wound models. Moreover, the methanol extract exerted remarkable wound healing activity and also demonstrated a significant and dose-dependent anti-inflammatory activity. Conclusion: The experimental study revealed that Centaurea iberica displays remarkable wound healing and anti-inflammatory activity.

- by Ipek Süntar
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- Folk Medicine, Complementary and Alternative Medicine, Plant Biology, Wound Healing

A novel elemanolide with an a-methyl-c-lactone moiety, 8a-O-(4-hydroxy-2-methylenebutanoyloxy)melitensine, in addition to four known sesquiterpene lactones also bearing the same lactone ring, melitensin, 11b,13 dihydrosalonitenolide, 8a-hydroxy-11b,13-dihydro-4-epi-sonchucarpolide, and 8a-hydroxy-11b,13-dihydro-onopordaldehyde have been isolated from the aerial parts of Centaurea pullata. The in vitro antibacterial and antifungal activities of the isolated sesquiterpene lactones were tested against six bacteria and eight fungal species, using a microdilution method. All compounds tested showed greater antibacterial and antifungal activities than the positive controls used. Moreover, the pharmacokinetic profile of these compounds was investigated using computational methods.

- by Catherine Koukoulitsa
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- Organic Chemistry, Prediction, Pharmacokinetics, Pharmacognosy

Twenty-nine compounds were isolated from the aerial parts of the Greek plant C. zuccariniana DC. The structures of the isolated compounds were established by means of NMR-( 1 H, 1 H-COSY, 1 H, 13 C-HSQC, HMBC, NOESY, and ROESY) and mass-spectral analyses. These compounds comprise 13 sesquiterpene lactones, 14 flavonoids, two lignans, and one simple lactone. Among the isolated sesquiterpene lactones, three are new, namely one heliangolide, (1E,4Z)-15-hydroxy-8a-O-(4'-acetoxy-3'-hydroxy-2'-methylidenebutanoyl)-6bH,7aH-germacra-1,4,11(13)-trien-6,12-olide; and two eudesmanolides, 8a-(4',5'-diacetoxyangeloyl)sonchucarpolide and one unusual eudesmanolide with an oxygenated bridge linking C(1) and C(4), named zuccarinin. The main sesquiterpene lactones were malacitenolide, cnicin, and 4'-O-acetylcnicin. These results are in agreement with those obtained from the previously studied Greek Centaurea sp. belonging to the section Acrolophus (Cass.) DC.; this finding could be of chemotaxonomic significance for the genus Centaurea.

- by Catherine Koukoulitsa
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- Organic Chemistry, Fungi, Magnetic Resonance Spectroscopy, Bacteria

Centaurea species are used for the treatment of various ailments in the popular medicine in some countries. This study was designed to examine antioxidant potentials and fatty acid profiles of five Centaurea species from Turkey flora. Antioxidant properties of methanolic extracts from these species were evaluated by six different methods: phosphomolybdenum assay, free radical scavenging assay, b-carotene/linoleic acid test system, metal chelating activity, ferric and cupric reducing power. Total phenolic and flavonoid concentrations of each extract were also determined using the Folin-Ciocalteu reagent and aluminum chloride. The results of these assay showed a significant antioxidant capacity in all researched extracts. Centaurea cheirolopha extract, with the highest amount of total phenolic and flavonoids, showed the highest antioxidant activities in all assay, except for metal chelating. Fatty acid profiles of these species were examined by GC-FID and 30 fatty acids were identified. Palmitic, linoleic, oleic, and linolenic acid were detected as the main components. The results of the study indicated that the Centaurea species can be considered as a source of new natural antioxidants and unsaturated fatty acids for food, cosmetic and pharmaceutical industries.

- by Gökhan Zengin
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- Free Radicals, Turkey, Free Radical, Pharmaceutical industry

ETHNOPHARMACOLOGICAL RELEVANCE: Atractylis gummifera L. and Centaurea ornata Willd. are locally marketed herbal remedies, even though in Spain it is forbidden to sell toxic plants like Atractylis gummifera. Intoxications in Spain are mainly due to accidental substitution of Centaurea ornata with Atractylis gummifera which may be fatal. AIM OF STUDY: The aim of this article is to analyse the current use and marketing of Atractylis gummifera and Centaurea ornata in Badajoz and analyse the ethnopharmacological ...

This paper presents a bioeconomic model for two agents, a cattle rancher and a non-rancher, with interdependencies between their individual effort of invasive weed management and profitability. Dynamic simulations allow us to find numerically the optimal effort of weed control over a 5-year time horizon under a variety of beginning infestation levels. In a base-case scenario without governmental cost-share of control costs, we find that efforts to control the weed are not profitable. The base-case scenarios also indicate that grazing contributes to giving the invasive weed a competitive edge. A second series of simulations include incentive payments for weed control which are set at the minimum level required to have a net positive impact on the rancher's profitability. From these simulations, we find that the level of infestation impacts the size of the incentive necessary to get the agent to control the weeds and that the incentive payments impact the level of effort of the ra...

- by Jason Hansen
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- Environmental Management, Population Dynamics, Invasive Species, Multidisciplinary

Background: Anti-inflammatory activities of medicinal plants have largely been attributed to their content of sesquiterpene lactones (SLs). SLs are predominantly found in the sunflower family Asteraceae and have been isolated from many plants of this family, particularly Centaurea. The antiinflammatory activities of extract of Centaurea ainetensis, a Lebanese endemic plant, and the isolated active molecule were assessed for their potential ant-inflammatory activities. Methods: Plant extract from Centaurea ainetensis, and the isolated active ingredient Salograviolide A (SA), a sesquiterpene lactones guaianolide, were used for the study. Western blotting and electrophoretic mobility shift assays were used to test the effects of the plant extract and SA on interleukin-1 (IL-1) induced increase in cyclooxygenase-2 (COX-2) levels and in nuclear factor-κB (NF-κB) translocation in an intestinal epithelial cell (IEC) of inflammation. Their effects on inflammation score and cytokine levels were also studied in an iodoacetoamide-induced rat model of inflammation. Results: Plant extract and SA were shown to reverse the effects observed by IL-1 on COX-2 levels and NF-κB translocation in IEC. SA decreased the level of inflammatory cytokines and the level of inflammation in the animal model. Conclusion: These findings suggest that SA may be useful in the development of natural therapies for inflammatory diseases.

- by Fadia Homeidan
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- Complementary and Alternative Medicine, Lebanon, Cell line, Mice

- by Elie Barbour
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- Nutrition and Dietetics, Traditional Medicine, Lebanon, Flavonoids

Background: Sesquiterpene lactones (SL) are plant secondary metabolites that are known for their anti-fungal, anti-bacterial, anti-inflammatory, and anti-tumor properties. Considering that several SL-derived drugs are currently in cancer clinical trials, we have tested two SL molecules, 3-β-methoxy-iso-seco-tanapartholide (β-tan) isolated from Achillea falcata and salograviolide A (Sal A) isolated from Centaurea ainetensis, for their anti-tumor properties. We used the mouse epidermal JB6P + cells as a model for tumor promotion and cellular transformation. Key players that are involved in cellular transformation and tumorigenesis are the AP-1 and NF-κB transcription factors; therefore, we assessed how β-tan and Sal A modulate their signaling pathways in JB6P + cells. Methods: The effects of β-tan and Sal A on the growth of normal and neoplastic keratinocytes and on the tumor promotion-responsive JB6P + cells were determined using the MTT assay. Anchorage-independent cell growth transformation assays were used to evaluate the anti-tumor promoting properties of these SL molecules in JB6P + cells and dual luciferase reporter assays and western blot analysis were used to investigate their effects on tumor promoter-induced AP-1 and NF-κB activities and protein levels of key AP-1 and NF-кB target genes. Results: β-tan and Sal A selectively inhibited tumor promoter-induced cell growth and transformation of JB6P + cells at concentrations that do not affect JB6P + and primary keratinocytes basal cell growth. In addition, both molecules reduced basal and tumor promoter-induced NF-κB transcriptional activities, differentially regulated basal and tumor promoter-induced AP-1 transcriptional activities, and modulated key players of the AP-1 and NF-κB signaling pathways.

- by Najat Saliba and +1
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- Complementary and Alternative Medicine, Signal Transduction, Middle East, Phytotherapy

Many of the best-selling anticancer drugs are plant-derived. We tested for the anticancer properties of extracts isolated from Centaurea ainetensis, a plant species endemic to Lebanon and which is often used in folk medicine. We performed bioassay-guided fractionation of Centaurea ainetensis extracts using a panel of normal and neoplastic murine cells to identify a component that is associated with antitumor activities. Among several compounds that were fractionated, the sesquiterpene lactone, Salograviolide A, was identified and found to exert the most significant growth inhibitory effects on neoplastic cells. At concentrations that were non-cytotoxic to primary keratinocytes, Centaurea ainetensis crude extract and Salograviolide A preferentially inhibited the proliferation of papilloma and squamous cell carcinoma (SCC) cell lines without significantly affecting the growth of normal cells. Flow cytometric analysis of DNA content indicated that the inhibition of cell proliferation by Centaurea ainetensis crude extract and Salograviolide A was due to G 0 /G 1 cell cycle arrest and increased pre-G 0 /G 1 , respectively. The increase in pre-G 0 /G 1 , and presumably apoptosis induction, in Salograviolide A-treated keratinocytes was confirmed by DNA Hoechst staining. Western blot analysis and electrophoretic mobility shift assay showed that both the crude extract and the isolated molecule differentially modulated key cell cycle and apoptotic regulators as well as NF-κB signaling. Salograviolide A-induced growth inhibition in neoplastic cells was mediated by the accumulation of reactive oxygen species (ROS) highlighting a potent oxidant role of this molecule. These studies suggest the potential therapeutic effects of Centaurea ainetensis, and its component, Salograviolide A, against epidermal squamous cell carcinogenesis.

- by Najat Saliba and +1
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- Oncology, Molecular Medicine, Cancer, Cell Cycle

- by Yavuz Selim Çakmak
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- Water, Antioxidants, Methanol, Cholinesterase inhibitors

and sharing with colleagues.

- by Yavuz Selim Çakmak
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- Turkey, Food Chemistry, Multidisciplinary, Antioxidants

The volatile oils obtained from the leaves and flowers of the Croatian endemic plant Centaurea ragusina L. were evaluated for antimicrobial activity. The chemical compositions, determined by GC and GC-MS, were complex, with sesquiterpenes the most abundant class of compound. Nonterpene hydrocarbons were also identified in high quantities, while acids and ketones were found in high quantities only in the leaf volatile oil. Aldehydes, alcohols, esters and other compounds were identified in lower quantities. Antimicrobial effects of the volatile samples were investigated by using the disc diffusion and microdilution assays. They were found to inhibit a wide range of bacteria and fungi, causing in vitro growth inhibition at a concentration of 250 μg/mL. The volatile oils displayed great antibacterial potential with MIC values ranging from 16 to 128 μg/mL against the Gram-positive bacteria Bacillus cereus, Clostridium perfringens, Enterococcus faecalis and Staphylococcus aureus, and less...

- by Olivera Politeo
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- Biochemistry, Organic Chemistry, Plant Biology, Biology

CITATIONS 4 READS 44 5 authors, including:

- by Massimo Cristofaro
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- Zoology, Introduced species, Weed Control, Host Specificity

In the present study, chemical compositions, antimicrobial and antioxidant activities of the essential oils of Sideritis erythrantha var. erythrantha (SE) and Sideritis erythrantha var. cedretorum (SC), which are endemic taxa in Turkey, were investigated. The essential oils obtained by hydrodistillation were analyzed by gas chromatography-mass spectrometry (GC-MS). a-Pinene was the major component of the essential oils of SC and SE. SC essential oil was as effective as antibiotic against methicillin-resistant Staphylococcus aureus (MRSA), vancomycin resistant Enterococcus faecalis (VRE), ampicillin resistant Haemophilus influenzae and vancomycin sensitive E. faecalis. Similarly, SE essential oil was also as effective as antibiotic against VRE and ampicillin resistant H. influenzae. Antioxidant activities of the essential oils of SC and SE were determined by 1,1-diphenyl-2-picrylhydrazyl (DPPH), b-carotene/linoleic acid and reducing power. Both essential oils exhibited weak antioxidant activity. This is the first report on antimicrobial and antioxidant activities of the essential oils of SC and SE.

- by Nurdan Sarac
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- Pharmacology, Botany, Analytical Chemistry, Organic Chemistry
- by Gökhan Zengin
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- Turkey, Multidisciplinary, Food Processing, Pharmaceutical industry

The classical approach to predicting the geographical extent of species invasions consists of training models in the native range and projecting them in distinct, potentially invasible areas. However, recent studies have demonstrated that this approach could be hampered by a change of the realized climatic niche, allowing invasive species to spread into habitats in the invaded ranges that are climatically distinct from those occupied in the native range. We propose an alternative approach that involves fitting models with pooled data from all ranges. We show that this pooled approach improves prediction of the extent of invasion of spotted knapweed (Centaurea maculosa) in North America on models based solely on the European native range. Furthermore, it performs equally well on models based on the invaded range, while ensuring the inclusion of areas with similar climate to the European niche, where the species is likely to spread further. We then compare projections from these models for 2080 under a severe climate warming scenario. Projections from the pooled models show fewer areas of intermediate climatic suitability than projections from the native or invaded range models, suggesting a better consensus among modelling techniques and reduced uncertainty.

- by Olivier Broennimann
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- Geography, Population Dynamics, Biological Sciences, Europe

- by Ülo Niinemets
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- Photosynthesis, Plant Biology, Fluorescence, Carotenoids

- by Erdal Bedir
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- Phytochemistry, Mass Spectrometry, Biological Sciences, Sesquiterpenes
- by Kate Krause
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- Environmental Management, Population Dynamics, Invasive Species, Multidisciplinary

An attempt was made to change the proportion of the parental genomes in interspecific hybrids Solanum nigrum ? S. tuberosum (ngr ? tbr) by means of repeated protoplast fusion. In order to enlarge the potato input into the hybrid genome, the protoplasts of two ngr ? tbr hybrids of different ploidy (7x and 8x) were fused with the protoplasts of two different diploid potato clones in three combinations. Protoclonal variability was studied in three populations of new ngr ? tbr allopolyploids maintained in vitro. The absolute nuclear DNA content (2C) was measured using flow cytometry to estimate the ploidy of the hybrids. The ploidy level of the selected clones was verified by chromosome counts in root meristems. The newly synthesized allopolyploids (75 clones) showed only a small gain in nuclear DNA content above the mean value determined for the parents, instead of the expected addition of an entire diploid potato genome to the combined parental ngr ? tbr genome. An increase in nuclear DNA was observed mostly in the clones having the 7x hybrid as a parent (75% of allopolyploids from two combinations). When the 8x hybrid was used as a parent, only two allopolyploids (5%) exhibited a significantly increased nuclear DNA content. The 8x level of ngr ? tbr allopolyploids was shown to be stable and was only occasionally exceeded. Somatic hybrids ngr ? tbr offer a model system for studying the molecular mechanism(s) and processes involved in stabilization and establishment of the synthetic Solanum allopolyploids.

- by Sonia Yakovlev
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- Plant Biology, Flow Cytometry, Biology, Genome Size

† Background and Aims In a mixed-ploidy population, strong frequency-dependent mating will lead to the elimination of the less common cytotype, unless prezygotic barriers enhance assortative mating. However, such barriers favouring cytotype coexistence have only rarely been explored. Here, an assessment is made of the mechanisms involved in formation of mixed-ploidy populations and coexistence of diploid plants and their closely related allotetraploid derivates from the Centaurea stoebe complex (Asteraceae). † Methods An investigation was made of microspatial and microhabitat distribution, life-history and fitness traits, flowering phenology, genetic relatedness of cytotypes and intercytotype gene flow (cpDNA and microsatellites) in six mixed-ploidy populations in Central Europe. † Key Results Diploids and tetraploids were genetically differentiated, thus corroborating the secondary origin of contact zones. The cytotypes were spatially segregated at all sites studied, with tetraploids colonizing preferentially drier and open microhabitats created by human-induced disturbances. Conversely, they were rare in more natural microsites and microsites with denser vegetation despite their superior persistence ability (polycarpic life cycle). The seed set of tetraploid plants was strongly influenced by their frequency in mixed-ploidy populations. Triploid hybrids originated from bidirectional hybridizations were extremely rare and almost completely sterile, indicating a strong postzygotic barrier between cytotypes. † Conclusions The findings suggest that tetraploids are later immigrants into already established diploid populations and that anthropogenic activities creating open niches favouring propagule introductions were the major factor shaping the non-random distribution and habitat segregation of cytotypes at fine spatial scale. Establishment and spread of tetraploids was further facilitated by their superior persistence through the perennial life cycle. The results highlight the importance of non-adaptive spatio-temporal processes in explaining microhabitat and microspatial segregation of cytotypes.

- by barbora singliarova
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- Phylogeography, Gene Flow, Plant Biology, Ecology

In the present study the chemical compositions of the essential oils from aerial parts of Centaurea davidovii Urum. and C. parilica Stoj. & Stef., both endemic to Bulgaria, were evaluated by GC and GC-MS. The main components of C. davidovii were β-eudesmol (13.9%), spathulenol (13.3%), caryophyllene oxide (10.1%) and (Z)-phytol (5.4%). The main components of Cparilica were hexadecanoic acid (39.2%), (Z,Z)-9,12-octadecadienoic acid (11.9%), caryophyllene oxide (6.8%) and spathulenol (6.6%). In order to compare the essential oils composition of these taxa and of related species a PCA analysis was carried out.

- by Svetlana Bancheva
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- Organic Chemistry, Plant Biology, Bulgaria, Plant extracts

Ethnopharmacological relevance: Several Centaurea species are used to alleviate pain and inflammatory symptoms in rheumatoid arthritis, high fever, and head ache in Turkish folk medicine. Aim of the study: The effectiveness of extracts, fractions and subfractions from dried Centaurea solstitialis L. subsp. solstitialis (CSS) (Asteraceae) roots and aerial parts were studied on mice. Materials and methods: The antinociceptive and antipyretic effects of Centaurea solstitialis L. subsp. solstitialis have been investigated by using p-benzoquinone-induced writhing reflex for antinociceptive activity and Freund's Complete Adjuvant-induced pyrexia model for antipyretic activity assessment in mice. Results: The ethanolic extract from the aerial parts of the plant was shown to possess significant antinociceptive (p < 0.01) and antipyretic activities (p < 0.01). The extract was then submitted to subsequent solvent extractions and chromatographic processes. Through bioassay-guided fractionation and isolation procedures two sesquiterpene lactones, solstitialin A and acetyl solstitialin, were isolated and defined as the active components of CSS. On the other hand, a comparative study was conducted on another species, Centaurea depressa Bieb., which has no similar folkloric utilization. Following the same fractionation chart same compounds were defined as the active ingredients. Conclusion: Results of the present study proved that aerial part of CSS possesses antinociceptive and antipyretic activities supporting the folkloric assertion in Turkish folk medicine. However, these effects seem not limited to CSS, some other Centaurea species, in fact, having no folkloric use might be equally active.

- by Esra Küpeli Akkol
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- Pain, Folk Medicine, Complementary and Alternative Medicine, Plant Biology

This study aimed to investigate the potential antitoxoplasma activities of extracts of the endemic plants Centaurea lydia and Phlomis nissolii in a fibroblast cell culture infected with T. gondii trophozoites. WI-38 cell lines treated with plant extracts (55 μg/mL each) and an untreated control were infected with 5×105 T. gondii trophozoites, and the number of parasites in the medium was determined on days 7, 14, and 24. No cytotoxic effects of C. lydia and P. nissolii extracts were detected at concentrations of 0.86-55 μg/mL in the WI-38 cell line, and the absence of the cytotoxicity of these extracts on the fibroblast cell line was considered as a positive effect. C. lydia extract at 55 μg/mL had marked activity against T. gondii trophozoites. A 47.5-fold increase was observed in the number of trophozoites in the control group, while a 84-fold decrease was found in the C. lydia extract group. However, a 36-fold increase was detected in the P. nissolii extract group, indicating no ...

- by Hüsniye Kayalar
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- Toxoplasma, Toxoplasmosis, Cell line, Plant extracts

Chronic ingestion of yellow star thistle ( Centaurea solstitialis) or Russian knapweed ( Acroptilon repens) causes nigropallidal encephalomalacia (NPE) in horses with an abrupt onset of neurologic signs characterized by dystonia of lips and tongue, inability to prehend food, depression, and locomotor deficits. The objectives of this study were to reexamine the pathologic alterations of NPE and to conduct an immunohistochemistry study using antibodies to tyrosine hydroxylase and α-synuclein, to determine whether NPE brains show histopathologic features resembling those in human Parkinson disease. Results confirm that the NPE lesions are located within the substantia nigra pars reticulata, sparing the cell bodies of the dopaminergic neurons in the substantia nigra pars compacta, and in the rostral portion of the globus pallidus, with partial disruption of dopaminergic (tyrosine hydroxylase–positive) fibers passing through the globus pallidus. No abnormal cytoplasmic inclusions like th...

- by Jon Patterson
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- Veterinary Pathology, Immunohistochemistry, Alpha Synuclein, Brain

Ecological impacts of invasive plant species are well documented, but the genetic response of native species to invasive dominance has been often overlooked. Invasive plants can drastically alter site conditions where they reach dominance, potentially exerting novel selective pressures on persistent native plant populations. Do native plant populations in old exotic invasions show evidence of selection when compared to conspecific populations in adjacent, noninvaded areas? We employ amplified fragment length polymorphism (AFLP) analysis to screen a large number of loci from two native grass species (Hesperostipa comata (Trin. & Rupr.) Barkworth and Sporobolus airoides Torr.) that occur in old infestations of the invasive forb Acroptilon repens. We then compare observed locus by locus F ST values with distributions of F ST estimated from simulation models under expectation of neutrality. We also compare the proportion of loci possibly linked to selection and those not linked to selection which exhibit parallel trends in divergence between two community types (invaded, noninvaded). Few loci (H. comata , 2.6%; S. airoides , 8.7%) in the two native grasses may be linked to genes under the influence of selection. Also, loci linked to selection showed a greater portion of parallel trends in divergence than neutral loci. Genetic similarities between community types were less than genetic similarity within community types suggesting differentiation in response to community alteration. These results indicate that a small portion of scored AFLP loci may be linked to genes undergoing selection tied to community dominance by an invasive species. We propose that native plants in communities dominated by exotic invasives may be undergoing natural selection.

- by Ann Hild
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- Genomics, Population Genetics, Invasive Species, Natural Selection

- by husniye kayalar
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- Toxoplasma, Toxoplasmosis, Cell line, Plant extracts

- by Massimo Cristofaro
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- Zoology, Geography, Life history, Bulgaria

Although exotic plant invasions threaten natural systems worldwide, we know little about the speciWc ecological impacts of invaders, including the magnitude of eVects and underlying mechanisms. Exotic plants are likely to impact higher trophic levels when they overrun native plant communities, aVecting habitat quality for breeding songbirds by altering food availability and/or nest predation levels. We studied chipping sparrows (Spizella passerina) breeding in savannas that were either dominated by native vegetation or invaded by spotted knapweed (Centaurea maculosa), an exotic forb that substantially reduces diversity and abundance of native herbaceous plant species. Chipping sparrows primarily nest in trees but forage on the ground, consuming seeds and arthropods. We found that predation rates did not diVer between nests at knapweed and native sites. However, initiation of Wrst nests was delayed at knapweed versus native sites, an eVect frequently associated with low food availability. Our seasonal fecundity model indicated that breeding delays could translate to diminished fecundity, including dramatic declines in the incidence of double brooding. Site Wdelity of breeding adults was also substantially reduced in knapweed compared to native habitats, as measured by return rates and shifts in territory locations between years. Declines in reproductive success and site Wdelity were greater for yearling versus older birds, and knapweed invasion appeared to exacerbate diVerences between age classes. In addition, grasshoppers, which represent an important prey resource, were substantially reduced in knapweed versus native habitats. Our results strongly suggest that knapweed invasion can impact chipping sparrow populations by reducing food availability. Food chain eVects may be an important mechanism by which strong plant invaders impact songbirds and other consumers.

- by Diana Six
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- Reproduction, Ecology, Seasonality, Animal migration

- by ertugrul gündüz
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- Turkey, Multidisciplinary, Fatty acids, Natural Product

Increased resource availability can promote invasion by exotic plants, raising concerns over the potential effects of global increases in the deposition of nitrogen (N). It is poorly understood why increased N favors exotics over natives. Fast growth may be a general trait of good invaders and these species may have exceptional abilities to increase growth rates in response to N deposition. Additionally, invaders commonly displace locals, and thus may have inherently greater competitive abilities. The mean growth response of Centaurea stoebe to two N levels was significantly greater than that of North American (NA) species. Growth responses to N did not vary among C. stoebe populations or NA species. Without supplemental N, NA species were better competitors than C. stoebe, and C. stoebe populations varied in competitive effects. The competitive effects of C. stoebe populations increased with N whereas the competitive effects of NA species decreased, eliminating the overall competitive advantage demonstrated by NA species in soil without N added. These results suggest that simulated N deposition may enhance C. stoebe invasion through increasing its growth and relative competitive advantage, and also indicate the possibility of local adaptation in competitive effects across the introduced range of an invader. Citation: He W-M, Montesinos D, Thelen GC, Callaway RM (2012) Growth and Competitive Effects of Centaurea stoebe Populations in Response to Simulated Nitrogen Deposition. PLoS ONE 7(4): e36257.

- by Giles Thelen
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- Multidisciplinary, Nitrogen, PLoS one, Introduced species

Three sesquiterpene lactones (centaurepensin ¼ chlorohyssopifolin A, chlorojanerin and 13-acetyl solstitialin A) isolated from the aerial parts of Centaurea solstitialis L. ssp. solstitialis (Asteraceae) were investigated for antimicrobial and antiviral activities. For the antimicrobial activity assessment, both standard and isolated strains of Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis, Staphylococcus aureus, Candida albicans and C. parapsilosis were employed by the microdilution method. Herpes simplex type-1, a DNA virus, and Parainfluenza, an RNA virus, were employed for the determination of the antiviral activity of these three sesquiterpene lactones using Vero cell lines. Ampicilline, ofloxocine, ketoconazole, fluconazole, acyclovir and oseltamivir were used as the reference drugs. 13-Acetyl solstitialin A displayed remarkable antibacterial activity against isolated strains of E. faecalis at 1 mg/ml concentration, which was close to the effective concentrations of ampicillin. The same compound also showed significant activity against the DNA virus, being as potent as the reference compound acyclovir at maximum and minimum concentrations of 16-o0.00006 mg/ml. This is the first report showing that 13-acetyl solstitialin A possesses significant antiviral activity.

- by Ilhan Gürbüz
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- Microbiology, Medical Microbiology, Cercopithecus aethiops, Bacteria