Dejan Gođevac

University of Belgrade, Beograd, Central Serbia, Serbia

Are you Dejan Gođevac?

Claim your profile

Publications (19)27.15 Total impact

  • Industrial Crops and Products 01/2014; 55:116–122. · 3.21 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In this study, the synthesis, structure and physical properties of two series of thermoplastic polyurethanes based on hydroxypropyl-terminated poly-(dimethylsiloxane) (HP-PDMS) or hydroxyethoxypropyl-terminated poly-(dimethylsiloxane) (EO-PDMS) as soft segments, and 4,4′-methylenediphenyl diisocyanate and 1,4-butanediol as hard segments were investigated. The poly-urethanes were synthesized by two-step polyaddition in solution. The effects of the type and content of PDMS segments on the structure, thermal and surface properties of copolymers were studied by 1 H-, 13 C-nuclear magnetic resonance (NMR) spectroscopy and two-dimensional NMR spectroscopies (heteronuclear multiple bond correlation (HMBC) and rotating-frame nuclear Overhauser effect (ROESY)), gel permeation chromatography (GPC), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), wide-angle X-ray scat-tering (WAXS), scanning electron microscopy (SEM) and water contact angle and water absorption measurements. Thermal properties investigated by DSC indicated that the presence of soft PDMS segments lowers the glass transition and melting temperatures of the hard phase as well as the degree of crys-tallinity. SEM analysis of the copolymers with a lower soft segment content confirmed the presence of spherulite superstructures, which arise from the crystallization of the hard segments. When compared with polyurethanes prepared from HP-PDMS, the copolymers synthesized from EO-PDMS with the same content of the soft segments had a higher degree of crystallinity, better thermal stability and a less hydrophobic surface. The obtained results showed that the synthesized polyurethanes had good thermal and surface
    Journal of the Serbian Chemical Society 01/2014; 79(7):843-866. · 0.91 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Some primary and secondary metabolites, as well as mineral nutrients in pulp, peel and juice obtained from four Serbian indigenous apple cultivars (Kožara, Kolačara, Budimka and Šumatovka) collected at two different developmental stages were studied. With advanced maturation soluble solids content, total and reducing sugars increased, while l-ascorbic acid content and titratable acidity decreased. Thirteen phenolic compounds were quantified using LC–MS/MS. The total phenolic content (TPC) ranged from 9.37 to 1440 mg/100 g fw, and 0.83 to 7.84 mg/100 g fw in peel and pulp samples, respectively. Quercetin derivatives were the major detected polyphenolic group. Majority of determined phenolic compounds were influenced by cultivar and the best sources were cultivars Kolačara and Budimka. The content of flavonols (with the exception of quercitrin) varied significantly depending on maturity at harvest. With regard to mineral analysis, K was the most abundant ranging from 104 to 158 mg/100 g fw in peel, 74.4 to 93.3 mg/100 g fw in pulp, and 77.1 to 91.5 mg/100 g fw in juice samples. Obtained results provide detailed information on nutritional potential and chemical composition of tested apple cultivars and thereby could encourage their wider cultivation and consumption.
    Journal of Food Composition and Analysis 01/2014; · 2.09 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A complex mixture of compounds was identified from the secretion of specimens of Unciger transsilvanicus. Phenol and p-cresol were detected for the first time in the family Julidae, and for the second time in the order Julida. Thirteen quinones were identified, with a great relative abundance of toloquinone and 2-methoxy-3-methyl-1,4-benzoqui-none. Hydroquinone was detected for the first time in the order Julida. Besides these compounds, isopentyl hexacosatetra-enoate and isopentyl esters of saturated and unsaturated fatty acids with chain lengths from C 14 to C20were identified. The most abundant non-quinone compound was isopentyl eicosenoate. The relative abundance of quinone and non-quinone in the defensive fluid of U. transsilvanicus was 77% and 23%, respectively. The phylogenetic importance of the registered compounds is briefly discussed.
    Archives of Biological Sciences 01/2014; 66(1):385-390. · 0.79 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Properties and biocompatibility of a series of thermoplastic poly(urethane-siloxane)s (TPUSs) based on α,ω-dihydroxy ethoxy propyl poly(dimethylsiloxane) (PDMS) for potential biomedical application were studied. Thin films of TPUSs with a different PDMS soft segment content were characterized by (1) H NMR, quantitative (13) C NMR, FTIR, AFM, DSC, DMA, contact angle, and water absorption measurements. Different techniques (FTIR, AFM and DMA) revealed that decrease of PDMS content promotes microphase separation in TPUSs. Samples with a higher PDMS content have more hydrophobic surface and better waterproof performances, but lower degree of crystallinity. Biocompatibility of TPUSs was examined following attachment of endothelial cells to the untreated copolymer surface or surface pre-treated with multicomponent protein mixture, and by using competitive protein adsorption assay. TPUSs did not exhibit any cytotoxicity toward endothelial cells, as measured by LDH and MTT assays. The untreated and proteins pre-adsorbed TPUS samples favored endothelial cells adhesion and growth, indicating good biocompatibility. All TPUSs adsorbed more albumin than fibrinogen in competitive protein adsorption experiment, which is feature regarded as beneficial for biocompatibility. The results indicate that TPUSs have good surface, thermo-mechanical and biocompatible properties, which can be tailored for biomedical application requirements by adequate selection of the soft/hard segments ratio of the copolymers.
    Journal of Biomedical Materials Research Part A 12/2013; · 2.83 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: This article summarizes the results of using cytokinesis-block micronucleus (CBMN) assay to evaluate the antioxidant potential of heterocyclic compounds. Most studies were carried out with naturally occurring heterocyclic compounds such as plant polyphenols: flavonoids, xanthones, coumarins, and ellagitannins, or plant derived products (juices, extracts, supplements) rich in bioactive heterocyclic compounds. There are also some studies dealing with synthetic heterocyclic antioxidants. CBMN assay is an in vitro study that has been used to evaluate antioxidant and protective effects of heterocyclic compounds on induced chromosome aberration in human lymphocytes.
    Mini Reviews in Medicinal Chemistry 10/2012; · 2.87 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: With the aim to evaluate the selectivity in the antitumor action, the cytotoxic activity of chamomile and marigold tea was tested against various malignant cell lines and against healthy immunocompetent peripheral blood mononuclear cells (PBMC). Chemical profiles of chamomile and marigold infusions and decoctions were analyzed by liquid chromatography/mass spectrometry; their total phenolic content and radical scavenging activity were determined, too. Results from present research demonstrate that chamomile and marigold tea exert selective dose-dependent cytotoxic action against target cancer cells. It is noteworthy that cytotoxicity of tea prepared from Calendula officinalis is remarkably higher in comparison to that from Matricaria recutita tea. The cytotoxic effect of chamomile tea is very weak to healthy PBMC, while the effect of marigold tea on PBMC is more pronounced. Marigold tea exerts highly selective antitumor effect especially to melanoma Fem-x cells in comparison to the action to normal healthy PBMC. Chemical analyses show that dominant phenolic compounds in examined infusions and decoctions are flavonoid glycosides and hydroxycinnamic acid derivatives. There are no considerable differences in total phenolic content and antioxidant activity between examined infusions. Antitumor potential of chamomile and marigold tea should be further investigated. Copyright © 2012 John Wiley & Sons, Ltd.
    Phytotherapy Research 08/2012; · 2.07 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: On the basis of LC/UV/MS analysis, 35 compounds from the extracts of seeds of black, red, and white currants (2 cultivars of each) were identified. Black currants cultivars contained protocatechuic acid and p-hydroxybenzoic acid, and traces of nitril containing phenolic acids. The presence of synapoyl glucoside was characteristic for cv. Malling Jewel. Sesquiterpenoid glycosides and carboxymethylindol glycosides were present mainly in white and red currant cultivars. Blackcurrant seeds contained higher amounts of flavonoids, especially rutin, isoquercetin, and taxifolin. The currant seed extracts were tested for in vitro protective effect on chromosome aberrations in peripheral human lymphocytes using cytochalasin-B blocked micronucleus (CBMN) assay. The frequency of MN was scored in binucleated cells, and the cultivars of black currants showed the best antioxidant potential. At a concentration of only 0.17 mg/mL, extract of the seed cv. Malling Jewel effected a decrease in the frequency of MN of 60% compared with control cell cultures. PRACTICAL APPLICATION: Our results provide evidence of protective effects of currant seed extracts and isolated pure compounds on cytogenetic damages in human lymphocytes. Thus, currant seed extracts could exert beneficial effects in quite a few diseases, for many of the biological actions have been attributed to their antioxidant properties.
    Journal of Food Science 06/2012; 77(7):C779-83. · 1.78 Impact Factor
  • Italian Journal of Food Science 01/2012; · 0.44 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Three European julid species, Cylindroiulus boleti, Leptoiulus trilineatus, and Megaphyllum bosniense, secrete mixtures of up to 12 different quinones. The major components in these species are 2-methoxy-3-methyl-1,4-benzoquinone and 2-methyl-1,4-benzoquinone. 2-Methoxy-5-methylhydroquinone is detected for the first time in the Class Diplopoda. 2-Hydroxy-3-methyl-1,4-benzoquinone, 2,3-dimethoxyhydroquinone, 2-methyl-3,4-methylendioxyphenol, and 2,3-dimethoxy-5-methylhydroquinone are registered for the first time in representatives of the family Julidae. The similar chemical composition of defense secretions in all analyzed European julids and Pacific spirobolids supports the idea of the chemical consistency of defensive compounds in juliform millipedes.
    Journal of Chemical Ecology 11/2011; 37(12):1358-64. · 2.46 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Većina geofilomorfnih hilopoda ima sternalne žlezde u kojima se sintetišu odbrambeni sekreti, međutim njihov hemijski sastav je i dalje nedovoljno poznat. Ventralni sekret geofilide Pachymerium ferrugineum (Koch) sadrži cijanidna jedinjenja i proteine; u ekstraktu „Geophilus vittatus (Rafinesque)“ identifikovani su mandelonitril, cijanovodonik, benzaldehid i benzoeva kiselina, dok smo tek nedavno kod vrste Clinopodes flavidus Koch pronašli 2- metil pentansku kiselinu, benzaldehid, benzoil nitril, metil benzenacetat i cijanovodonik. U ovoj studiji proučavan je odbrambeni sekret mediteranske vrste Himantarium gabrielis (Linnaeus). Za gasno-hromatografsku i gasno-masenu analizu korišćeno je po pet mužjaka i ženki prikupljenih na Cetinju, u Crnoj Gori, u maju 2011. godine. Upoređivanjem snimljenih masenih spektara sa odgovarajućim bazama podataka identifikovali smo četiri jedinjenja: benzaldehid (71,13%), benzoilnitril (18,94%), benzil nitril (1,62%) i mandelonitril benzoat (8,31%), što je potvrđeno poređenjem retencionih indeksa sa dostupnom literaturom. Njihov relativni udeo je izračunat iz odgovarajućih površina pikova gasnog hromatograma, a prisustvo cijanovodonika je dokazano pikrinskim testom. Najinteresantnije hemijsko svojstvo odbrambenog sekreta H. gabrielis je prisustvo benzil nitrila koji do sada nije izolovan iz ekstrakata Myriapoda, kao i mandelonitril benzoata koji je po prvi put registrovan kod Chilopoda. Pored isparljive komponente, ventralni sekret analiziranog taksona sadrži i lepljivu komponentu (verovatno proteinske prirode), koja deluje više mehanički nego hemijski.
    SYMPOSIUM OF ENTOMOLOGISTS OF SERBIA 2011, Donji Milanovac; 09/2011
  • [Show abstract] [Hide abstract]
    ABSTRACT: Mushrooms are useful in balancing human diet and treating different health problems. The main determinant of the fluidity of erythrocyte membranes and rheologic properties of blood is the lipid composition of the membrane, which directly depends on lipids present in the diet. Lipid profiles of 4 European wild edible mushrooms, as well as the ability of mushroom lipids to modify the fluidity of erythrocyte membrane, were examined by using gas chromatography-mass spectometry, gas chromatography-flame ionization detector, and electron paramagnetic resonance spin probing technique. Lipids from 2 species--Macrolepiota procera and Collybia platyphylla--provoked an increase in erythrocyte membrane fluidity. Therefore, introduction of these and other wild mushrooms with similar lipid profiles to the human diet could be very beneficial in the treatment of hypertension and other cardiovascular diseases related to decreased fluidity of erythrocyte membranes.
    Journal of medicinal food 08/2011; 14(11):1330-7. · 1.39 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The tentative identification of seed extracts from 3 cultivars of blackberry (blackberry seed extracts [BSEs]) constituents was performed by LC/UV/MS technique. The identified compounds belonged to ellagitannins, galic acid derivatives, and ellagic acid derivatives. Two ellagitannins, Lambertianin C and Sanguiniin H-6, and an ellagic acid derivative, 4-α-L-arabinofuranosylellagic acid, were isolated using semipreparative High-performance liquid chromatography. The structure elucidations were based on high resolution-mass spectrometry and nuclear magnetic resonance studies. The BSEs and 3 isolated pure compounds were tested for in vitro protective effect on chromosome aberrations in peripheral human lymphocytes using cytochalasin-B blocked micronucleus (MN) assay. The frequency of MN was scored in binucleated cells, and nuclear proliferation index was calculated. Among the tested extracts, the seeds of cv. Thornfree at concentration of 1 μg/mL exhibit the most prominent effect decreasing the frequency of MN by 62.4%, when compared with the controls cell cultures. Antioxidant potential of pure ellagitannins cannot explain the strong effect of BSEs. The assumption was that better antioxidant effect of BSEs result from synergistic effects of individual compounds contained in the extracts and/or some minor components possessed strong activity. PraCTICAL APPLICATION: Our results provide evidence of protective effects of BSEs and isolated pure compounds on cytogenetic damages in human lymphocytes. Thus, BSEs could exert beneficial effects in quite a few diseases, because many of the biological actions have been attributed to their antioxidant properties.
    Journal of Food Science 08/2011; 76(7):C1039-43. · 1.78 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: In this paper, examination of the aerial parts of seven Senecio species from Serbia and Montenegro is reported. Phytochemical investigation of Senecio erucifolius led to the isolation and characterization of semiquinol butyl 2-(1-hydroxy-4-oxocyclohexa-2,5-dienyl)acetate (I), along with methyl 2-(1-hydroxy-4-oxocyclohexa-2,5-dienyl)acetate (jacaranone, II), and methyl 2-(4-hidroxyphenyl)acetate (III). The structure of I was established based on spectroscopic studies (1H- and 13C-NMR, IR, and CI-MS). Compound II was also isolated from S. carpathicus and S. subalpinus. The presence of jacaranone in the methanol extracts of S. wagneri, S. othonnae, and S. paludosus was confirmed by LC/ESI-TOF MS. Keywords Senecio species–semiquinol and phenol compounds–NMR–LC/ESI-TOF MS
    Chemical Papers- Slovak Academy of Sciences 01/2011; 65(1):90-92. · 0.88 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: A new allose-containing triterpenoid saponin (1), along with a known saponin (2), were isolated from the aerial parts of Cephalaria ambrosioides. Their structures were determined by spectroscopic (2D-NMR and ESI-MS) methods. The preferred conformation of 1 was determined by the NOESY spectrum.
    Natural product research 09/2010; 24(14):1307-12. · 1.01 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The chemical composition and free radical scavenging properties of the MeOH extract of Hypericum richeri and its subsequent CHCl(3), n-BuOH, EtOAc and aqueous extracts were investigated. Four quercetin-3-O-glycosides, three myricetin-3-O-glycosides, 3-O- and 5-O-caffeoylquinic acid, quercetin, I3,II8-biapigenin, pseudohypericin and hypericin were identified. The constituents of the extracts were quantified using HPLC-DAD (high-performance liquid chromatography-diode array detector). Isolation of the compounds from n-BuOH and EtOAc extracts was conducted by column chromatography. Antioxidant capacity of the extracts was evaluated by superoxide radical and ABTS√(+) scavenging assays and inhibition of lipid peroxidation. The EtOAc extract of H. richeri was the most potent antioxidant in all experiments. Free radical scavenging compounds were identified by HPLC-DPPH√ (high-performance liquid chromatography-2,2-diphenyl-1-picrylhydrazyl) post-column derivatisation method, where all phenolic compounds except I3,II8-biapigenin exhibited radical scavenging properties. This is the first report of the presence of myricetin-3-O-rutinoside, myricetin-3-O-galactoside, myricetin-3-O-glucoside, 5-O-caffeoylquinic acid and I3,II8-biapigenin in H. richeri.
    Natural product research 09/2009; 25(3):175-87. · 1.01 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: A total of 20 components were identified in Allium ursinum volatile oil (AUVO) by GC–MS, and 10 of them are found for the first time in this plant species. The antioxidant capacity of AUVO was examined by β-carotene–linoleic acid bleaching, lipid peroxidation by Fenton reaction, EPR spin-probing assay using stable nitroxide radicals, DPPH, and ABTS+ scavenging assays. Reaction mechanism of the volatile oil components with nitroxide radicals, based on IR spectra analysis, is proposed. AUVO demonstrated poor scavenging ability against DPPH and ABTS+ comparing to synthetic antioxidants BHT and trolox, while in β-carotene–linoleic acid system AUVO showed an effect comparable to those for BHT. AUVO was also capable to scavenge stable nitroxide radicals such as water-soluble Tempone, and 7-DS and 12-DS, incorporated into the liposome membrane. Finally, AUVO increased membrane fluidity, which could be an important feature for further in vivo investigation of some disorders, such as hypertension and atherosclerosis.
    Food Chemistry. 01/2008;
  • Biochemical Systematics and Ecology - BIOCHEM SYST ECOL. 01/2006; 34(12):890-893.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Electron paramagnetic resonance (EPR) spin-trapping and spin-probing techniques were applied to determine antioxidant activity of extracts of catkin, leaves, and spiny burs of Castanea sativa against physiologically relevant reactive species—superoxide and hydroxyl radical generated in simple chemical systems and hydrogen peroxide applied on erythrocytes. Efflux of K+ was used as a marker of membrane integrity. Chemical composition of extracts was analyzed using HPLC/DAD and LC/MS. Extracts showed high antioxidative capacity against superoxide but lower activity against hydroxyl radical. They protected fluidity and integrity of membranes of erythrocytes exposed to hydrogen peroxide. Levels of derivatives of ellagitannins showed positive correlation with the antioxidative activity of extracts. Therefore, ellagitannins from chestnut extracts could represent easily accessible natural antioxidants and beneficial component of human diet in pathophysiological conditions related to oxidative stress. In conclusion, EPR spectroscopy represents a valuable tool for evaluation of antioxidant activity in both hydrophilic and lipophilic media.
    Food Biophysics 4(2):126-133. · 1.64 Impact Factor

Publication Stats

26 Citations
27.15 Total Impact Points

Institutions

  • 2010–2014
    • University of Belgrade
      • Institute for Chemistry, Technology and Metallurgy
      Beograd, Central Serbia, Serbia
  • 2012
    • Institut za onkologiju i radiologiju Srbije
      Beograd, Central Serbia, Serbia
  • 2011–2012
    • Faculty of Technology and Metallurgy, University of Belgrade
      Beograd, Central Serbia, Serbia
    • Polytechnic of Rijeka
      Vitipolis, Primorsko-Goranska, Croatia