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Ekstrakcija lantanoida i aktinoida iz jalovišta fabrike glinice u Zvorniku; ispitivanje potencijala jalovišta za dodatnu preradu
No full textU ovom radu ispitivana je efikasnost različitih ekstrakcionih sredstava prilikom izdvajanja elemenata retkih zemalja, aktinoida i pratećih metala iz uzoraka iz fabrike glinice ,,Nova Alumina“ u Zvorniku. Kao ekstrakciona sredstva su korišćeni rastvori carske vode (aqua regina), oksalatne kiseline i amonijum-okstalata, kao i hidroksilamin-hidrohlorid (pH = 1,5). Koncentracije elemenata u uzorcima određene su metodom indukovano spregnute plazme sa optičkom emisionom spektrometrijom (ICP-OES).
Na osnovu dobijenih rezultata zaključeno je da je carska voda pokazala najveću efikasnost kao sredstvo za izdvajanje većine elemenata usled svoje jake oksidacione sposobnosti, dok rastvor oksalata i hidroksilamin-hidrohlorid pokazuju selektivnost prema pojedinim elementima retkih zemalja. Posebno je uočeno da su elementi Ce, Pb, Nd, Pr, U i Eu u većoj meri ekstrahovani primenom hidroksilamin-hidrohlorida (pH =1,59 u odnosu na rastvor oksalata, dok je uranijum izdvojen isključivo rastvorom hidroksilamina.
Rezultati ukazuju na značaj izbora ekstrakcionog sredstva u zavisnosti od ciljanih elemenata. Dobijeni rezultati mogu poslužiti kao osnova za razvoj efikasnih, selektivnih i ekološki prihvatljivih metoda za izdvajanje ovih elemenata iz zemljanih izvora
Development, chemical characterization, and cytotoxic potential of novel iridium(III) complexes
No full textOptimization of cell-based assays for identifying compounds with anti-inflammatory and anti-allergic activity
No full textWith the global rise in allergy cases, there is a pressing need for efficient and cost-effective methods to screen therapeutic compounds. We optimized two cell-based assays in 48-well format for this purpose: (1) activation of RAW 264.7 macrophages for testing potential anti-inflammatory compounds, and (2) RBL-2H3 basophil/mast cell degranulation assay for evaluating compounds with potential allergy-relief properties. RAW 264.7 cells, upon lipopolysaccharide (LPS) stimulation (1 µg/mL), produce pro-inflammatory mediators such as nitric oxide, TNF-α, and IL-6, allowing assessment of anti-inflammatory activity. RBL-2H3 cells, which express high-affinity IgE receptors, when sensitized with antigen-specific IgE and triggered to degranulate, release β-hexosaminidase and histamine—mimicking allergic responses. Arthrospira platensis extract (10 and 100 µg/mL) and budesonide (Pulmicort) (2, 10, 20 µM), a corticosteroid with known anti-allergic properties, were tested for their anti-inflammatory activity.
Algae are a rich source of bioactive compounds, including proteins, vitamins, and minerals, making them promising candidates for therapeutic applications across various fields of medicine. As controls, ketotifen fumarate (10 and 50 µM) and calcium ionophore (1 and 10 µM) were included. Ketotifen fumarate is an antihistamine and mast cell stabilizer, whereas calcium ionophore functions by artificiallyincreasing intracellular calcium levels, thereby inducing mast cell or basophil degranulation. To optimize the RBL-2H3 degranulation assay, DNP-BSA (albumin from bovine serum, 2,4-dinitrophenylated) and anti-DNP IgE were used. DNP-BSA serves as the antigen, stimulating a cellular response in the study of IgE-mediated allergic reactions. These optimized assays provide reliable, scalable tools for identifying new compounds with therapeutic potential in inflammation and allergy
Razvoj alginatnih filmova obogaćenih zelenim ekstraktima u funkciji produženja svežine prehrambenih proizvoda
No full textPlastika je omogućila veliki napredak u proizvodnji ambalaže za hranu, ali njena nerazgradivost dovodi do ozbiljnih ekoloških posledica. Biorazgradivi, prirodni i jestivi materijali za pakovanje sve više privlače pažnju, jer nude održivu alternativu i mogu doprineti očuvanju i bezbednosti hrane. Cilj ovog master rada bio je razvoj alginatnih tečnih filmova radi poboljšanja očuvanja svežine hrane, kroz unapređenje njihovih funkcionalnih i zaštitnih svojstava inkorporacijom ekstrakata iz poljoprivrednog otpada dobijenih primenom prirodnih eutektičkih rastvarača (Natural Deep Eutectic Solvents, NADES). Za ekstrakciju biološki aktivnih jedinjenja iz ljuski crvenog luka, kore jabuke i kore đumbira korišćeni su različiti NADES sistemi, koji u svom sastavu sadrže glicerol, prolin, ksilitol i jabučnu kiselinu. Ekstrakti su evaluirani u in vitro testovima i ispitana je antioksidativna aktivnost, antimikrobno dejstvo i inhibicija tamnjenja hrane (anti-browning). Ekstrakti koji sadrže prolin ispoljavaju najjači antioksidativni potencijal, dok ekstrakti koji sadrže jabučnu kiselinu pokazuju značajan antimikrobni potencijal i sposobnost inhibicije tirozinaze. Izabrani biološki aktivni ekstrakti inkorporirani u alginatne filmove, čija su struktura, hemijska svojstva i vizuelni izgled karakterisani pomoću SEM (Scanning electron microscopy, Skenirajuća elektronska mikroskopija) i FTIR (Fourier Transform Infrared spectroscopy, Infracrvena spektroskopija sa Fourierovom transformacijom) tehnika. Inkorporacija NADES-a i ekstrakta uticala je na morfologiju, boju i sjaj filmova, ali su sve formulacije formirale kontinuirane i dobro prijanjajuće premaze. Ispitana je efikasnost pripremljenih filmova u produženju svežine jagoda, borovnica i sira. Rezultati su pokazali da primena filmova doprinosi produženju svežine, naročito kod voća sa visokim sadržajem vlage, kao što su jagode. Filmovi obogaćeni biološki aktivnim ekstraktima pokazali su jače zaštitno dejstvo, naglašavajući značaj formulacije filma. Ovo istraživanje pokazuje da alginatni biofilmovi, obogaćenih NADES ekstraktima iz poljoprivrednog otpada, predstavljaju perspektivne jestive premaze sa unapređenim konzervirajućim svojstvima, doprinoseći poboljšanju kvaliteta hrane i valorizaciji otpada
Synthesis and application of FeMg-modified hydrochar for efficient removal of lead ions from aqueous solution
No full textThis study explores the utilization of waste grape pomace-derived hydrochar as an efficientadsorbent for lead (Pb2+) removal from aqueous solutions. Hydrochar was produced viahydrothermal carbonization (HTC) at 220 ◦C, followed by doping with magnesium andiron salts, and subsequent pyrolysis at 300 ◦C to obtain Fe/Mg-pyro-hydrochar (FeMgPHC). The material’s structural and morphological changes after Pb2+ adsorption wereexamined using FTIR. FTIR revealed chemisorption and ion exchange as key mechanisms,shown by decreased hydroxyl, carbonyl, and metal–oxygen peaks after Pb2+ adsorption.Adsorption tests under varying pH, contact time, and initial Pb2+ concentrations revealedoptimal removal at pH 5. Kinetic modeling indicated that the process follows a pseudosecond-order model, suggesting chemisorption as the dominant mechanism. Isothermanalysis showed that the Sips model best describes the equilibrium, with a maximumtheoretical adsorption capacity of 157.24 mg/g. Overall, the simple two-step synthesis—HTC followed by pyrolysis—combined with metal doping yields a highly effective andsustainable adsorbent for Pb2+ ion removal from wastewater
Global DNA Methylation in Poorly Controlled Type 2 Diabetes Mellitus: Association with Redox and Inflammatory Biomarkers
No full textAlthough emerging evidence suggests that epigenetic mechanisms contribute to the pathogenesis and progression of type 2 diabetes mellitus (T2DM), data remain limited for patients with suboptimal metabolic control. The aim of this study was to assess global DNA methylation in patients with poorly controlled T2DM and to identify diabetes-related factors associated with DNA methylation levels. The study included 107 patients and 50 healthy controls. Global DNA methylation (5mC) was measured by UHPLC-DAD method. Pro-oxidant and antioxidant biomarkers, advanced glycation end-products, high-sensitivity C-reactive protein (hsCRP) and complete blood count were determined and leukocyte indices calculated. Patients had a significantly lower 5mC than controls (3.56 ± 0.31% vs. 4.00 ± 0.68%; p < 0.001), with further reductions observed in those with longer disease duration and diabetic foot ulcers. Oxidative stress and inflammatory biomarkers were higher in the patient group. DNA hypomethylation was associated with a higher monocyte-to-lymphocyte ratio and hsCRP, pro-oxidant–antioxidant balance, ischemia-modified albumin, and advanced oxidation protein products levels. Conversely, 5mC levels showed positive correlations with total antioxidant status and total sulfhydryl groups. Principal component analysis identified five key factors: proinflammatory, pro-oxidant, aging, hyperglycemic, and antioxidant. The pro-oxidant factor emerged as the sole independent predictor of global DNA hypomethylation in T2DM (OR = 2.294; p = 0.027). Our results indicate that global DNA hypomethylation could be a biomarker of T2DM progression, reflecting the complex interactions between oxidative stress, inflammation, and epigenetic modifications in T2DM
Investigating the Impact of Nosema Infection in Beehives on Honey Quality Using Fluorescence Spectroscopy and Chemometrics
No full textThis study investigates the impact of Nosema infection in beehives on the physico-chemical and biochemical properties and spectral characteristics of honey as indicators of honey quality. Comprehensive analyses were performed on honey samples from hives with varying levels of Nosema infection, examining water content, free acidity, optical rotation, electrical conductivity, sugar composition, catalase activity, and pollen content. Honey from highly infected hives showed higher water content (up to 17.3%), lower optical rotation, reduced electrical conductivity, decreased glucose levels, and increased sucrose levels. Principal component analysis (PCA) identified distinct clustering of samples based on infection levels, with changes in the sugar profile, particularly higher phenolic compounds, correlating with increased infection levels. Fluorescence spectroscopy combined with PARAFAC modeling identified proteins and phenolic compounds as key discriminators of honey from infected hives. Correlation and PLS modeling further demonstrated strong relationships between spectral features and honey properties, including catalase activity and pollen content. This research presents a novel approach to evaluating the impact of Nosema infection on honey quality by integrating physico-chemical and biochemical analyses and sugar composition profiling with advanced spectroscopic techniques. These insights are invaluable for improving bee health monitoring practices and advancing sustainability in the beekeeping and honey production industries
Praćenje promena redoks parametara u serumu pre i mesec dana nakon buster doze COVID-19 vakcina
No full textCilj ovog istraživanja bio je da se ispitaju promene redoks parametara u serumu ispitanika pre i mesec
dana nakon primene buster (treće) doze različitih COVID-19 vakcina, uz razmatranje uticaja
prethodne SARS-CoV-2 infekcije, starosti, pola i komorbiditeta na redoks homeostazu. Istraživanje
je sprovedeno kao deo longitudinalne kohortne studije koja je obuhvatila 410 ispitanika vakcinisanih
sa tri doze Pfizer-BioNTech, Sinopharm [Vero Cell]-Inactivated, Sputnik V, ili heterolognom
kombinacijom Sinopharm/Pfizer-BioNTech vakcina. Analizirani su parametri redoks statusa u
serumu – ukupni proteini, albumin, tioli, nitriti, kao i antioksidativna aktivnost određena DPPH i
FRAP testovima.
Rezultati su pokazali da treća doza vakcine izaziva promene u oksidativno-antioksidativnoj ravnoteži,
koje zavise od tipa vakcine i COVID-19 statusa ispitanika. Najizraženije promene uočene su kod
heterologno vakcinisanih ispitanika (Sinopharm/Pfizer-BioNTech), gde su zabeleženi značajni
padovi koncentracije serumskog albumina i DPPH aktivnosti u obe podgrupe (COVID-19+ i COVID-
19–). Kod ispitanika vakcinisanih Sinopharm [Vero Cell]-Inactivated COVID-19 vakcinom
registrovan je pad ukupnih proteina, dok su kod grupa koje su primile Pfizer-BioNTech i Sputnik V
vakcine uočeni slični trendovi smanjenja DPPH aktivnosti. FRAP vrednosti i koncentracija nitrita su
ostale stabilne, što ukazuje na očuvanu neenzimsku antioksidativnu komponentu i odsustvo značajnih
nitro-oksidativnih promena u serumu ispitanika.
Dobijeni rezultati sugerišu da buster doza COVID-19 vakcina kratkoročno može izazvati prolazno
smanjenje antioksidativnog kapaciteta seruma, verovatno usled imunološke aktivacije i povećane
potrošnje antioksidanasa. Ove promene su bile izraženije kod starijih ispitanika i osoba sa
komorbiditetima, što potvrđuje povezanost redoks homeostaze sa imunskim i metaboličkim statusom
organizma
Uticaj perfluorooktanske kiseline na produkciju siderofora (pioverdina i piočelina) i pigmenta (piocijanina) kod bakterija roda Pseudomonas izolovanih iz PFAS-kontaminiranog sedimenta
No full textSiderofore su sekundarni metaboliti koje proizvode bakterije i gljive kako bi preuzele gvožđe iz svoje okoline i time obezbedile dovoljnu količinu u ćeliji za različite potrebe. Perfluorooktanska kiselina (PFOA) je jedna od glavnih zagađujućih supstanci životne sredine iz grupe PFAS molekula koja ima sposobnost akumulacije u živim sistemima što dovodi do različitih negativnih efekata. U ranijim istražvanjima je pokazano da siderofore i enzimi zavisni od gvožđa učestvuju u odbrani bakterije od štetnih efekata PFOA, odnosno u njegovoj degradaciji.
Cilj ovog rada bio je ispitivanje uticaja PFOA na produkciju siderofora od strane Pseudomonas chlororaphis, podvrsta aurantiaca PF-16, izolovane iz zemljišnog mikrobnog konzorcijuma za koji je pokazano da ima sposobnost degradovanja PFOA. Analizirana je produkcija siderofora pioverdina i piočelina, kao i pigmenta piocijanina.
Ispitivanje produkcije siderofora i piocijanina ispitivano je u prisustvu i odsustvu PFOA. Praćena je fermentacija na svakih 24 h, 4 dana zaredom. Produkcija siderofora i piocijanina određena je spektrofotometrijski. Pokazano je da Pseudomonas chlororaphis u prisustvu PFOA produkuje pioverdin kao glavnu sideroforu, zatim piočelin samo u početku, dok se proizvodnja piocijanina uopšte ne dešava
Tuning crystal packing and reactivity through electrostatc and dispersion interactions: The case of phenytoin and its derivatives
No full textHydantoin derivatives represent a versatile class of heterocycles, known for their pharmacological properties. Because drug efficacy often depends on the fine-tuning of weak intermolecular (non-covalent) interactions, analysis of the crystal structure of a drug molecule is important, as it enables deciphering its interaction profile. In this study, the crystal packing of phenytoin and its selected derivatives were examined through dimeric motifs with different recognition modes using force-field calculations and a density functional theory (DFT) approach. The relatively polar ethoxyacetyl group at the N3 position of the hydantoin ring, capable of forming hydrogen bonds, enhances the contribution of electrostatic and polar components to the total interaction energy. In contrast, the long alkyl chain promotes hydrophobic contacts, leading to dispersion forces dominating over electrostatic interactions. The reactivity of phenytoin and its derivatives were further evaluated by examining the influence of these substituents using conceptual density functional theory (CDFT) descriptors. These findings demonstrate that substituents significantly affect crystal packing and the balance of non-covalent interactions, providing valuable insights for optimizing molecular recognition and drug–target interactions in the design of new therapeutic agents