Koncentracije elemenata u tkivima klena (squalus cephalus) iz akumulacija Nacionalnog parka „Tara”

Planinsko područje Tare nalazi se na krajnjem zapadu Srbije. Sa severne i zapadne strane ograničeno je dolinom Drine, sa jugozapada dolinom Rzava, sa juga plitkom kremanskom udolinom koja ga odvaja od zlatiborske površi. Ceo prostor Nacionalnog parka obuhvata: planinu Taru, Crni vrh, Zvezdu, Stolac, kanjon Drine sa Perućcem i okolinu Bajine Bašte. Nacionalni park „Tara“ i njegova uža zaštitna zona raspolaže rekama i potocima koji pripadaju uglavnom gornjim i delimično srednjim pastrmskim regionima. Najznačajnije reke su Rača, Derventa sa pritokama, Brusnički potok sa pritokama, Karaklijski Rzav i Baturski Rzav i reka Jarevac. U Nacionalnom parku „Tara“ formirano je nekoliko veštačkih jezera različitog tipa. Akumulacija „Perućac“ je veštačko jezero nastalo u rečnom koritu reke Drine, njenim pregrađivanjem betonskom branom. Na osnovu lokacije, pripada nizinskom tipu. Akumulacija „Zaovine“ je po lokaciji visinskog tipa, a po načinu nastanka reverzibilna. Nastaje izbacivanjem vode iz akumulacije „Perućac“ i sakupljanja vode od Karakliskog i Baturskog Rzava i drugih manjih pritoka. Akumulacija „Spajići“ je visinska sabirna akumulacija koja nastaje od proceđene vode iz jezera „Zaovine“, te reke Zmajevačke i Popovića potoka. Jezero „Kruščica“ nastaje od Karaklijskog i Baturskog Rzava i koristi se kao pijaća voda (Hegediš, 2012). Ribolovne vode NP „Tara“ naseljava 28 vrsta riba iz sedam familija, a šaranske vrste (Ciprinidae) dominiraju po brojnosti sa 17 vrsta. Klen (Squalius cephalus) je ciprinidna vrsta ribe, široko rasprostranjena u Srbiji južno od Save i Dunava dok je u Vojvodini redak. U Srbiji je popularna sportsko-rekreativna ribolovna vrsta i lovi se različitim tehnikama ribolova. U akumulacijama Zaovine, Spaići i Kruščica klen je najzastupljenija vrsta, dok je i u akumulaciji Perućac prisutan u značajnom broju (Hegediš, 2012). Tokom terenskih istraživanja 2014. godine ispitivan je nivo akumulacije 17 elemenata u tkivima (mišić, jetra, škrge) klena iz četiri akumulacije – Perućac, Zaovine, Spaići i Kruščica. Ribe se nalaze na vrhu lanaca ishrane u vodenoj sredini i često u organizmu akumuliraju velike količine pojedinih teških metala (Yilmaz et al., 2007). Takođe se smatraju i jednim od najosetljivijih akvatičnih organizama na prisustvo toksičnih materija u vodi (Alibabić i sar., 2007). Ribe se često koriste kao bazični organizmi po pitanju pozicije u lancima ishrane, kao i u ishrani ljudi, zbog njihovog potencijala za bioakumulaciju toksičnih materija i njihove osetljivosti na čak i male koncentracije mutagena (Szefer et al., 1990; Višnjić-Jeftić et al., 2010). Jedinke klenova sa Perućca su se na osnovu analize glavnih komponenata (PCA – Principal Components Analysis) izdvajale po višim koncentracijama Cu i Zn u jetri, kao i B i Cu u mišićima; jedinke sa Zaovina se izdvajaju po koncentracijama Sr, Mo, Fe, Cr, Al, Hg u jetri višim nego u jedinkama sa drugih akumulacija, Mn, Sr, Hg, Mo i Cr u mišićima i Al, Sr, Li i Hg u škrgama; jedinke sa akumulacije Kruščica se izdvajaju po koncentracijama Pb, Mn i Ni u jetri, kao i, Mo, Mn, Fe, Pb i Cr u škrgama; jedinke sa akumulacije Spaići su bile grupisane između jedinki sa drugih analiziranih akumulacija, nisu se izdvajale po koncentracijama bilo kog analiziranog elementa u bilo kom tkivu, a najsličnije su bile jedinkama sa Perućca

Intestinal content analyses of pumpkinseed Lepomis gibbosus (Linnaeus, 1785) in five small reservoirs – central Serbia

Lepomis gibbosus (pumpkinseed) was first recorded as a non-native fish in Serbia in the 1930s in the Tisza River. The species currently inhabits almost the entire region of the Black Sea basin in Serbia, but has no economic value. The current range of the pumpkinseed covers more than 50% of the total Serbian area and is also naturalised in Serbian waters. The pumpkinseed feeds on bottom fauna, small fish, fish roe and juvenile fish, which together with competition for habitat and spawning sites can have a negative impact on native species. The most common prey of younger specimens is zooplankton, while adult specimens feed on larger organisms such as larvae and pupae of insects, molluscs or crustaceans. The composition of the prey varies seasonally and depends on the composition of the community. The main objective of the study was to analyse the differences in the feeding habits of pumpkinseed in five reservoir. Samples were collected from five reservoirs in central Serbia (<200 asl, Markovačko, Topola, Vlaški Do, Jatagan, Kudreč) using standard electrofishing equipment. All sampled reservoirs had mud substrate, except Jatagan Reservoir, which had gravel substrate. The sampled fish were identified on site based on morphological characteristics using identification keys. The sampled fish were measured using total body length and weight. The total sample consisted of 354 pumpkinseed individuals whose body weight ranged from 3.66–9.52 g and body length from 6.01–8.41 cm. The number of individuals with intestinal content was 282, while the number of individuals with empty stomachs was 72. The following macroinvertebrate taxa were identified during the examination of the gut contents: aquatic insects (Chironomidae, Chironomidae-pupae, Diptera, Ceratopogonidae, Trichoptera, Ephemeroptera, Odonata, Heteroptera, Coleoptera), Gammaridae, Mollusca, Bivalvia, Gastropoda, Nematoda. Undetermined terrestrial insects were also recorded. Most prey were found in the Kudreč Reservoir, and the greatest diversity was in the Topola Reservoir. Jatagan Reservoir had the lowest number of prey items, which may be due to the substrate type. The high number of aquatic insect taxa could be explained by the small surface area of the reservoir and the presence of aquatic vegetation

Procena sadržaja metala i elemenata u tkivima 4 komercijalne vrste riba iz Dunava kod Beograda

Cilj ovog istraživanja je bio da se proceni akumulacija elemenata u četiri komercijalne vrste riba na dva lokaliteta na Dunavu, u Beogradu. U ovom istraživanju, određene su koncentracije 11 elemenata (As, Cd, Cr, Co, Cu, Fe, Hg, Mn, Ni, Se, i Zn) u tkivima mišića, jetre i škrga sledećih vrsta: mrena (Barbus barbus), deverika (Abramis brama), štuka (Esox lucius) i smuđ (Sander lucioperca). Rezultati su ukazali da je distribucija metala i elemenata u tragovima u različitim tkivima specifična za vrstu. Koncentracije As, Cd, Fe, Hg, i Zn u mišićima riba su bile ispod maksimalno dozvoljenih koncentracija MDK, utvrđenih od strane EU i Republike Srbije. Na osnovu dobijenih rezultata, neophodno je uspostaviti program stalnog monitoringa na Dunavu u Beogradskom regionu

Mapping differential elemental accumulation in fish tissues: importance of fish tissue sampling standardization

The concentrations of As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se and Zn in the muscle, gills, liver and intestine of the wels catfish (Silurus glanis) from the Danube River were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). The aim of the study was to determine whether in complex muscle/skin, gill filament/gill arch, proximal/distal liver and proximal/median/distal intestine samples, particular components differ in concentrations of the analyzed elements. Results indicated that there were no differences in the accumulation of different elements between the proximal and distal liver segments and between the proximal and median intestine sections. Conversely, elemental accumulation patterns in muscle and skin differed significantly. Significant differences were also observed between the gill arch and filaments, as well as between the distal and the two upper intestine sections. Findings indicated the importance of detailed reporting of tissue sampling, i. e. whether the skin was included in the muscle sample, as well as if the gill arch and filaments were analyzed together. Due to a potential bias that can be produced by different muscle/skin or gill arch/filament ratios included in the sample, we strongly recommend that they should not be analyzed together. Results of the present study might be of interest to the scientific community and stakeholders involved in aquatic ecosystem monitoring programs

PROCENA DIVERZITETA VRSTA RIBA I KVALITETA VODE U PET AKUMULACIJA U SRBIJI ZASNOVANA NA ŠENONOVOM INDEKSU DIVERZITETA

Značaj riba kao bioindikatora kvaliteta vode potvrđen je brojnim istraživanjima, a zasniva se na njihovoj dugovečnosti, mobilnosti, pripadnosti različitim funkcionalnim trofičkim grupama i osetljivosti na širok spektar antropogenih stresora. Cilj ovog istraživanja bilo je poređenje diverziteta vrsta riba u akumulacijama Garaši, Perućac, Zaovine, Ovčar i Međuvršje na osnovu Šenonovog indeksa diverziteta (H), kao i procena kvaliteta vode na osnovu poređenja vrednosti ovog indeksa sa rezultatima merenja fizičkih i hemijskih parametara vode. Uzorkovanje riba je vršeno mrežama (20-50 m dužine, 1.5-2 m visine i 28-100 mm promera okca) tokom leta 2017. godine. Ukupno je uzorkovano 795 jedinki riba koje pripadaju 21 vrsti. Multiparametarska sonda YSI 6600 V2-2 korišćena je za prikupljanje podataka o fizičkim, hemijskim i biološkim karakteristikama ispitivanih akumulacija. Praćene su vrednosti pH, rastvorenog kiseonika (DO) i hlorofila a. Prema vrednostima Šenonovog indeksa diverziteta za pomenute akumulacije, diverzitet naselja riba pokazao je sledeći trend: Perućac (H = 1.81) > Ovčar (H = 1.69) > Garaši (H = 1.52) > Zaovine (H = 1.45) > Međuvršje (H = 1.27). A kumulacije G araši, Perućac i O včar i male su k valitet vode koji spada u II-III klasu, dok je lošiji kvalitet (III-IV klasa) zabeležen za akumulacije Zaovine i Međuvršje. Procena kvaliteta vode na osnovu Šenonovog indeksa diverziteta poklapa se sa procenom kvaliteta vode baziranom na merenju pH vrednosti, rastvorenog kiseonika (DO) i hlorofila a, osim za akumulaciju Zaovine. Rezultati istraživanja sugerišu da kombinovanje Šenonovog indeksa diverziteta i merenja fizičkih i hemijskih parametara može pružiti pouzdanu procenu kvaliteta vode u istraživanim akumulacijama

Synthesis, Characterization and Biological Studies of Organoselenium trans-Palladium(II) Complexes

Background: Over the years, transition metal complexes have exhibited significant antimicrobial and antitumor activity. It all started with cisplatin discovery, but due to the large number of side effects it shows, there is a growing need to find a new metal-based compound with higher selectivity and activity on more tumors. Objectives: Two novel trans-palladium(II) complexes with organoselenium compounds as ligands, [Pd(L1)2Cl2] (L1 = 5-(phenylselanylmethyl)-dihydrofuran-2(3H)-one) and [Pd(L2)2Cl2] (L2 = 2- methyl-5-(phenylselanylmethyl)- tetrahydrofuran) were synthesized, in the text referred to as Pd-Se1 and Pd-Se2. Also, a structurally similar trans-palladium(II) complex, [Pd(L3)2Cl2] (L3= 2,2- dimethyl-3-(phenylselanylmethyl)-tetrahydro-2H-pyran ) was synthesized according to an already published work and is referred to as Pd-Se3. The interaction of synthesized complexes with DNA and bovine serum albumin was observed. Also, antimicrobial activity and in vitro testing, cell viability, and cytotoxic effects of synthesized ligands and complexes on human epithelial colorectal cancer cell line HCT-116 were studied. Molecular docking simulations were performed to understand better the binding modes of the complexes reported in this paper with DNA and BSA, as well as to comprehend their antimicrobial activity. Methods: The interactions of the synthesized complexes with DNA and bovine serum albumin were done using UV-Vis and emission spectral studies as well as docking studies. Antimicrobial activity was tested by determining the minimum inhibitory concentrations (MIC) and minimum microbicidal concentration (MMC) using the resazurin microdilution plate method. Cytotoxic activity on cancer cells was studied by MTT test. Results: The Pd(II) complexes showed a significant binding affinity for calf thymus DNA and bovine serum albumin by UV-Vis and emission spectral studies. The intensity of antimicrobial activity varied with the complexes Pd-Se1 and Pd-Se3, showing significantly higher activity than the corresponding ligand. The most significant activity was shown on Pseudomonas aeruginosa. Under standardized laboratory conditions for in vitro testing, cell viability and cytotoxic effects of synthesized ligands and complexes were studied on human epithelial colorectal cancer cell line HCT-116, where Pd-Se2 showed some significant cytotoxic effects. Conclusion: The newly synthesized complexes have the potential to be further investigated as metallodrugs.Publishe

Length-Weight Relationship And Condition Factor Of The Cactus Roach (Rutilus Virgo) In The Perućac Reservoir (Serbia)

The length-weight relationship and condition of 35 individuals of the cactus roach, caught in June 2017 in the Perućac reservoir, were analysed. The average length (± SD) of the sampled individuals was 29.8 ± 6.1cm and the average weight (± SD) was 334 ± 215 g. Age ranged from 2+ to 5+ years, and almost half of individuals were aged 2+. The regres-sion coefficient of the length-weight relationship was b > 3, which indicates a positive allometric growth. The Fulton’s condition factor ranged from 0.94 to 1.27, with the mean value (± SD) of 1.09 ± 0.09. Allometric condition factor ranged from 0.49 to 0.62, with the mean value (± SD) of 0.56 ± 0.04

Residual life estimation of a thermal power plant component: The high-pressure turbine housing case

This study focuses on the estimation of residual life of damaged thermal power plant components. The high-pressure turbine housing was chosen as an example of thermal power plant component where, during the years of exploitation, damage appeared in the form of dominant crack. Residual life estimation procedure, based upon experimental and numerical methods has been introduced and applied. Material properties were determined experimentally both at room and operating temperature, while all necessary calculations were performed by the special finite element method, so-called X-FEM. The residual life estimation of the damaged high-pressure turbine housing was performed by applying the Paris's law for crack growth analysis