146 research outputs found
Pyrrolizidine alkaloids from seven wild-growing Senecio species in Serbia and Montenegro
The genus Senecio (family Asteraceae) is one of the largest in the world. It comprises about 1100 species which are the rich source of pyrrolizidine alkaloids. Plants containing pyrrolizidine alkaloids are among the most important sources of human and animal exposure to plant toxins and carcinogens. The pyrrolizidine alkaloids of seven Senecio species (S. erucifolius, S. othonnae, S. wagneri, S. subalpinus, S. carpathicus, S. paludosus and S. rupestris) were studied. Fourteen alkaloids were isolated and their structures determined from spectroscopic data (1H- and 13C-NMR, IR and MS). Five of them were identified in S. erucifolius, four in S. othonnae, two in S. wagneri, four in S. subalpinus, two in S. carpathicus, three in S. paludosus and three in S. rupestris. Seven pyrrolizidine alkaloids were found for the first time in particular species. The results have chemotaxonomic importance. The cytotoxic activity and antimicrobial activity of some alkaloids were also studied
Lignani biljne vrste Achillea lingulata
Five lignans with a 2.6-diaryl-3.7-dioabicyclo[3,3.0]octane skeleton epieudesmin. kobusin, pinoresinol. fargesin and sesartemin, were isolated from the aerial parts and roots, of Achillea lingulata. Their structures were identified by comparison of their H-1-NMR and MS data to those in the literature. Fargesin and pinoresinol have not been isolated previously from any species of the genus Achillea.Iz nadzemnog dela i korena biljne vrste Achillea lingulata izolovano je pet lignana 2,6-diaril-3.7-dioksabicikloŠ3.3.0Ćoktanskog tipa. To su epieudesmin, kobusin, pinorezinol, fargezin i sezartemin. Izolovani lignani su identifikovani na osnovu identičnosti wihovih NMR i masenih spektara sa spektrima iz literature. Fargezin i pinorezinol nisu bili do sada izolovani iz biljnih vrsta roda Achillea
Compositional characteristics of the essential oil of Pimpinella anisum and Foeniculum vulgare grown in Serbia
The essential oils obtained by hydrodistillation from the mature fruits of Pimpinella anisum and Foeniculum vulgare were analyzed by GC-MS. The oil of aniseed was characterized by higher amounts of trans-anethole (96.80%) than fennel essential oil (83.43%). The isomer of trans-anethole, methyl chavicol (estragol) was also present in both plants, with 1.36% in fennel and 0.19% in aniseed. Apart from these two phenylpropanoids, nine sesquiterpenes and one monoterpene were present in essential oil of Pimpinella anisum, which constituted the other 3.01% of essential oil, but only γ-himachalene was present with more than 1%. In the case of fennel, eight monoterpenes constituted the other 15.21% of essential oil, and limonene and fenchone were present with contributions of 9.34 and 4.58%, respectively. © 2015 Institute of Botany and Botanical Garden Jevremovac, Belgrade
Antifungalna aktivnost terpenoida davanonskog tipa izolovanih iz Artemisia lobelii Var. canescens
Five tetrahydrofuran sesquiterpenes, so-called davanones, and coumarin umbelliferone isolated from Artemisia lobelii All. var. canescens (DC.) Briqu, were tested for antifungal activity. All the compounds inhibited the growth of the applied fungi. The overall activity of one of them, 2-hydroxy-2,6,10-trimethyl-7,10-epoxy-dodeca-3,11-dien-5-on, was comparable to that of the antibiotic bifonazole.Pet tetrahidrofuranskih terpenoida davanonskog tipa i kumarin umbeliferon koji su prethodno izolovani iz biljne vrste Aretemisia lobelii var. conescens ispitivani su na antifungalnu aktivnost. Sva testirana jedinjenja inhibiraju rast primenjenih kultura gljiva. Najveću aktivnost, koja se može meriti sa aktivnošću komercijalnog antibiotika bifonazola, pokazuje 2-hidroksi-2,6,10-trimetil-7,10-epoksidodeka-3,11-dien-5-on
Impaired hypoglycaemia awareness in type 1 diabetes:lessons from the lab
Hypoglycaemia remains the most common metabolic adverse effect of insulin and sulfonylurea therapy in diabetes. Repeated exposure to hypoglycaemia leads to a change in the symptom complex that characterises hypoglycaemia, culminating in a clinical phenomenon referred to as impaired awareness of hypoglycaemia (IAH). IAH effects approximately 20–25% of people with type 1 diabetes and increases the risk of severe hypoglycaemia. This review focuses on the mechanisms that are responsible for the much higher frequency of hypoglycaemia in people with diabetes compared with those without, and subsequently how repeated exposure to hypoglycaemia leads to the development of IAH. The mechanisms that result in IAH development are incompletely understood and likely to reflect changes in multiple aspects of the counterregulatory response to hypoglycaemia, from adaptations within glucose and non-glucose-sensing cells to changes in the integrative networks that govern glucose homeostasis. Finally, we propose that the general process that incorporates many of these changes and results in IAH following recurrent hypoglycaemia is a form of adaptive memory called ‘habituation’
Flavonoidi iz cvetova Cephalaria pastricensis i njihova antiradikalska aktivnost
Two flavonoid glycosides 1 and 2 having the luteolin structure were isolated from flowers of the endemic plant species Cephalaria pastricensis. They were identified by (1)H and (13)C NMR, as well as UV/Vis spectroscopy. The structures of 1 and 2 were also confirmed by the spectral data of aglycones and TLC of the sugars obtained after acid hydrolysis. Flavones 1 and 2 showed significant antiradical activity in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay.Iz cvetova Cephalaria pastricensis izolovana su dva heterozidna flavonoida sa luteolinskim aglikonom (1 i 2). Wihova struktura je određena primenom 1H i 13C-NMR i UV spektroskopije. Strukture flavona 1 i 2 su potvrđene i spektrima aglikona, odnosno tankoslojnom hromatografijom oslobođenih šećera nakon kisele hidrolize. Jedinjenja 1 i 2 su pokazala značajnu antiradikalsku aktivnost u 1,1-difenil-2 pikrilhidrazil (DPPH) testu
Fitohemijsko ispitivanje biljne vrste Anthemis cotula
The investigation of roots of Anthemis cotula (Asteraceae) from cast Serbia revealed, in addition to polyacetylenes previously isolated from the same species, three prenylated 4-hydroxyacetophenones, detected for the first time in any Anthemis species. It is possible that they act as phytoalexins in the plant. From the aerial parts, six linear sesquiterpene lactones (four known and two new ones), as well as two known flavones, apigenin and hispidulin, were isolated.Novo ispitivanje korena biljke A. cotula (Asteraceae) pokazalo je, pored četiri već izolovana poliacetilena, i prisustvo tri prenilovana 4-hidroksiacetofenona koji do sada nisu bili izolovani iz ovog roda. Iz nadzemnog dela biljke izolovano je šest linearnih seskviterpenskih laktona, od koji su dva nova, dok su preostali ranije nađeni u istoj biljci. Takođe su u nadzemnom delu identifikovana dva poznata flavona, apigenin i hispidulin
Antiproliferative Activity of Natural Flavonoid Fustin Isolated from the Heartwood of Cotinus Coggygria Scop. Against Breast and Colon Cancer Cell Lines
Background and objective: Cotinus coggygria Scop. is a valuable medicinal plant species with pronounced pharmacological potential due to its numerous biological activities. The herb is characterized by a high content of polyphenols among which is fustin. The anticancer activities of fustin, however, are extremely weakly studied. The aim of the present study was to investigate the in vitro antiproliferative potential of fustin isolated from the heartwood of C. coggygria against cell lines originating from two of the most common cancer types – breast (MDA-MB-231 and MCF7), and colon cancer (Colon 26). Materials and methods: Cell growth inhibitory properties of fustin were examined by MTT assay. Subsequently, phase-contrast and fl uorescence microscopy analysis as well as colonyforming assay were carried out on the most sensitive to the cytostatic action of the fustin cell line. Results: The obtained results showed that fustin reduced the proliferation of all studied cell lines. The highest cytostatic eff ect was registered towards breast cancer MDA-MB-231 cells with a half maximal inhibitory concentration (IC50) value of 56.02 μg/ ml followed by colon cancer cells with an IC50 of 78.07 μg/ml. MCF7 cell proliferation was least aff ected with a calculated IC50 of 187.8 μg/ml. Further investigations on breast cancer MDA-MB-231 cells indicated decreased density of cell monolayer and some morphological alterations, signifi cant attenuation in the number of viable cells, and diminished clonogenic ability of cells after fustin exposure. Conclusion: It could be concluded that fustin isolated from the heartwood of medicinal plant C. coggygria possesses marked antiproliferative properties against breast cancer cell line MDA-MB-231 which will be a subject of our more detailed future investigations
Nonacosan-10-ol and n-Alkanes in Leaves of Pinus pinaster
In leaf cuticular wax of Pinus pinaster, content of nonacosan-10-ol is high (77.1% on average). n-Alkanes ranged from C18 to C35 with the most dominant C29 (24.8%). The carbon preference index (CPItotal) ranged from 3.1 to 5.6 (4.0 on average), while the average chain length (ACLtotal) ranged from 14.0 to 17.0 (14.8 on average). Long-chain n-alkanes (n-C25-35) strongly dominated (80.1%) over middle-chain (n-C21-24= 18.9%) and short-chain (n-C18-20= 0.9%) n-alkanes
Chemical Composition, Total Phenols and Flavonoids Contents and Antioxidant Activity as Nutritive Potential of Roasted Hazelnut Skins (Corylus avellana L.)
The present study evaluates natural composition of Serbian roasted hazelnut skins (HS) with potential role in application as functional nutrient of various food products. Total phenols (TPC) and flavonoids contents (TFC) in HS extracts obtained with dierent ethanol concentrations (10%—I, 50%—II and 96%—III) and their antioxidant activities were investigated. The highest total phenols content (706.0 9.7 mgGAE/gextract) was observed in 96% ethanol HS extract. Ethanol HS extracts showed very high antioxidant activity with eective concentrations (EC50) ranged between 0.052 and 0.066 mg/mL. The phenol and flavonoid content of roasted HS extracts I–III was determined by HPLC-ESI-MS/MS analyses. Contents of lipids, proteins, carbohydrates, metals, and C, H, N, S elements in roasted HS were also determined. Relatively high C/N, C/P and C/N/P ratios, rich metal contents and fatty acids composition indicated that hazelnut skin might be a good candidate for use as either human or fungal functional nutrient. In addition, possible application of phenolic HS extracts as UV booster was studied by recording UV spectra (220–440 nm) of 10 mg/L of HS extracts I–III combined with 10 mg/L of chemical sunscreen agent benzophenone-3 and in vitro sun protection factor (SPF) was calculated
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