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Petrological and organic geochemical insights into the peat-forming environmental settings during the deposition of the early Oligocene Pirin coal deposit, SW Bulgaria
No full textThe up to 30-m-thick Brezhani coal seam in the Pirin deposit (SW Bulgaria) is the only coal of early Oligocene age on the territory of Bulgaria, providing important insights into peat-forming environments during that period. The coal seam was investigated using organic petrography, bulk organic geochemistry and biomarker analysis. Coal is predominantly composed of detrovitrinite with subordinate collotelinite and abundant corpogelinite. Liptinite macerals are mostly represented by alginite and suberinite, and locally resinite. The coal commonly contains semi-inertinized (oxidized) root tissues without apparent thermal influence. The low- to moderate tissue preservation indicates predominant contribution from plants with low preservation potential. Rare resin-impregnated woody tissues argue for peat accumulation within a sparsely forested shrub-dominated mire. Biomarker proxies indicate a contribution from mixed vegetational communities, composed of flowering plants and bald cypresses. A contribution of aquatic macrophytes is also evident. Variable ash yields and sulfur contents indicate changeable water supply and pH conditions. However, high sulfur contents and ash yields in a large number of the samples denote organic matter accumulation within a topogenous mesotrophic marginal limno-telmatic mire. Plant material accumulated at or very close to the water surface in a predominantly water-logged environment, indicated by strong gelification. The initial oxidizing conditions were quickly shifted to reductive settings due to flooding of the peat surface with possible seasonal dynamics. Low maturity of the organic matter and limited hydrocarbon generation potential are evident from the low vitrinite reflectance (avg. Ro = 0.52 %), biomarker parameters and Rock-Eval data
Izolovanje i karakterizacija glikozilovanog flavonoida iz biljne vrste Euphorbia amygdaloides L.
No full textEuphorbia amygdaloides L. je višegodišnja zeljasta biljka iz porodice Euphorbiaceae Juss. Biljne vrste ove porodice poznate su po prisustvu brojnih specijalizovanih metabolita sa potencijalnim biološkim aktivnostima. Među njima se posebno ističu diterpenski i triterpenski derivati, ali i glikozilovani flavonoidi. Za glikozilovane flavonoide dokazana su antimikrobna svojstva, naročito prema Gram-pozitivnim bakterijama, kao i antioksidativna svojstva. Prisustvo ovih specijalizovanih metabolita ukazuje na značajan potencijal ovih biljaka za dalja istraživanja i moguću primenu u razvoju biljnih preparata u farmaceutskoj industriji. U okviru ovog istraživanja ispitana je biljna vrsta E. amygdaloides, iz koje je izolovan i okarakterisan glikozilovani flavonoid kvercitrin
Plasma and Serum LC-MS Lipidomic Fingerprints of Bipolar Disorder and Schizophrenia
No full textBipolar disorder (BD) and schizophrenia (SCH) are results of the complex interactions between genetic and environmental factors, and the underlying pathophysiology is not yet completely understood. The current diagnostic criteria for psychiatric diagnosis are based purely on clinical phenomenology and they are limited to psychiatrist judgment after a standardized clinical interview, with no precise biomarkers used to discriminate between the disorders. Besides gaps in the understanding and diagnosis of these diseases, there is also a need for personalized and precise approaches to patients through customized medical treatment and reliable monitoring of treatment response. To fulfill existing gaps, the establishment of disorder biomarker sets is a necessary step. LC-MS lipidomic blood sample analysis is one of the ongoing omics approaches. In the last ten years, several studies have identified alterations in lipid metabolism associated with BD and SCH, and this review summarizes current knowledge on their lipidomic patterns, which is essential for identifying lipid biomarkers. Currently, findings indicate decreases in plasmalogens and acyl-carnitines, along with increases in certain triacylglycerol species, shared by both conditions. In contrast, serum LC-MS lipidomic profiles of sphingolipids including ceramides could be unique to BD, indicating the need for further investigation in future studies
Imunski odgovor THP-1 makrofaga na alergen Ara h 1 izolovan iz sirovog kikirikija i modulatorna uloga lipida kikirikija
No full textCilj ovog rada je in vitro ispitivanje imunološkog odgovora THP-1 makrofaga na alergen Ara h 1 izolovan iz sirovog kikirikija, kao i uticaj lipida iz ulja kikirikija na ovaj odgovor, praćenjem vezivanja/preuzimanja FITC-obeleženog alergena, sekrecije citokina i aktivacije NF-κB signalnog puta.
THP-1 monociti su diferencirani u makrofage upotrebom PMA. Ara h 1 je izolovan i prečišćen iz sirovog kikirikija kombinacijom taložnih metoda i afinitetne hromatografije. Deo proteina je obeležen FITC-om za potrebe praćenja vezivanja/preuzimanja alergena od strane makrofaga. Proteinski ekstrakt sirovog kikirikija pripremljen je alkalnom ekstrakcijom, uz precipitaciju proteina u kiselim uslovima.
Efikasnost vezivanje FITC-obeleženog Ara h 1 nakon ćelijskog tretmana, samostalno i u prisustvu lipida iz ulja kikirikija, praćena je FACS analizom. THP-1 makrofagi su tretirani sa Ara h 1 i uljem kikirikija, i u ćelijskom supernatantu je ELISA tehnikom kvantifikovana količina sekretovanih citokina IL-6 i IL-10. Makrofagi su transfektovani NF-κB-luciferaza reporterskim plazmidom, i aktivacija signalnog puta nakon tretmana ćelija sa Ara h 1, uljem kikirikija i proteinskim ekstraktom sirovog kikirikija praćena je merenjem hemiluminescencije
Uticaj mikroalgalne biomase i minerala gline na sadržaj ukupne rastvorne organske supstance i raspodelu n-alkana u uzorku terapeutskog blata iz Bujanovačke banje
No full textOvaj master rad ima dva cilja. Prvi cilj je ispitivanje promena u raspodeli i relativnoj obilnosti n-alkana tokom procesa sazrevanja peloida, sa posebnim osvrtom na katalitički uticaj minerala gline. Drugi cilj je procena mogućnosti formiranja laboratorijski dizajniranog mikroalgalnog peloida putem obogaćivanja organske materije mikroalgalnim jedinjenjima. Istraživanje obuhvata analizu rastvorne organske materije peloida iz Bujanovačke banje, gde se sazrevanje geološkog prepeloidnog uzorka odvija tokom dve godine u otvorenim bazenima, što omogućava praćenje dugoročnih promena u raspodeli i relativnoj obilnosti n-alkana i procenu mineraloških uticaja na transformaciju organske materije. Paralelno s tim, pripremljen je laboratorijski dizajniran mikroalgalni peloid, koji kombinuje Bujanovačko terapeutsko blato sa mikroalgom Scenedesmus sp., kako bi se ispitalo kratkoročno obogaćivanje peloida metabolitima mikroalgi. S obzirom na značajan uticaj mikroalgi na kozmetička svojstva, dobijeni rezultati predstavljaju osnovu za budući razvoj i primenu dermato-kozmetičkih mikroalgalnih peloida u banjskim tretmanima
Imobilizacija lakaze iz Trametes versicolor u L-histidinom modifikovanom alginatu
No full textCilj ovog rada je upoređivanje uspešnosti imobilizacije lakaze iz Trametes versicolor u Na-alginatnim i L-histidin modifikovanim alginatnim hidrogelovima i biokompozitima dobijenim umrežavanjem jonima cinka i kalcijuma. Imobilizati su okarakterisani određivanjem temperaturne stabilnosti, specifične aktivnosti imobilizata i stabilnosti tokom skladištenja nedelju dana na 4oC
Orbital contributions to the magnetic shielding of cyclo[2n]carbons (n = 3–12)
No full textNatural chemical shielding (NCS) analysis yields erroneous magnetic shielding values (or NICS, which is the negative of magnetic shielding) for the core, σ and in-plane π orbitals of cyclo[2n]carbons (n = 3–12), assuming that the external magnetic field acts perpendicular to the ring plane. The most diagnostic are the unphysically large contributions of core electrons to the shielding inside the rings. An alternative way to estimate the contribution of the in-plane π-system to shielding values is proposed and is based on the addition of a hydrogen atom outside each carbon atom in the plane of the cyclo[2n]carbon ring, while keeping its geometry intact. The πin contributions are then estimated as the difference between the total shielding values of cyclo[2n]carbon and the total shielding values of a ring with added Hs. This, however, includes the C−H bond effects near the carbon framework
Optimization of Extraction Conditions for Phenolic Compounds from Potato Tubers: LC-MS Phenolic Profile as a Powerful Tool to Assess the Genotypes, Vegetation Period, and Production Systems of Potato
No full textFive different extraction methods were assessed to select an optimal procedure for extracting the phenolic antioxidants from potato tubers. Total phenolic content and antioxidant capacity were determined for each type of extraction. In total, 144 samples of four potato varieties from three production systems, over a period of three years, were analyzed. The results show that TPC and RSA tests can be used as parameters for differentiating potato parts and variety and to distinguish the samples depending on ripening time and the production system. Higher values of TPC and RSA were observed in samples from the organic cultivation system compared to integral and conventional cultivation in the same cultivar. Finally, by the employment of UHPLC-LTQ Orbitrap XL, fifty-nine phenolic compounds were identified. It was concluded that the phenolic profile is a powerful tool for confirming botanical origin, distinguishing between genotypes, and distinguishing various production systems of potato
Hybrids of 4-aminoquinolines and adamantane as inhibitors of AChE: Scientific paper
No full textAlzheimer’s disease (AD) is an incurable and progressive neurodegenerative disorder that causes cognitive capabilities and memory loss and damage to brain functionality and structure. From diverse possibilities for drug development, the inhibition of acetylcholinesterase (AChE) remains as dominant treatment of symptoms. In our continued investigation of long-chain derivatives of 4-aminoquinoline containing an adamantyl (Ad) group, six new derivatives that differ in the substitution at the terminal amino group or the Ad moiety were synthesised. Their inhibition of AChE, in silico drug-likeness, the potential for passing through the blood-brain barrier (BBB) and possible binding modes with AChE for the most active compounds were investigated. It was shown that introducing OH, Br or acetamide group increases the inhibitory potency compared with less polar compounds containing the benzyl group as the second substituent at the amino group. Analysis of in silico obtained parameters defined by Lipinsky's rule showed that neither compound is likely to cross the BBB because of violation of at least one of the rules, in general, log P and a number of rotatable bonds (RB). Docking of the most active compounds to AChE suggests that compounds act as dual-binding site inhibitors since they have simultaneous interaction with catalytic and peripheral anionic sites of AChE. The substituents on the Ad could be the ones that determine the mode of binding into the enzyme and provide interactions that stabilise the complex between the compound and AChE
Sinteza azobenzena i 2-benzilidenbenzo[b]tiofen-3(2H)-ona
No full textPrvi segment ovog završnog rada je posvećen sintezi derivata azobenzena koji su dobijeni primenom Baeyer-Millsove reakcije kondenzacije. U drugom delu rada sintetisan je benzo[b]tiofen-3(2H)-on intramolekulskim Friedel-Craftsovim acilovanjem fenil-tiosirćetne kiseline, koji je u daljim reakcijama aldolne kondenzacije sa različitim derivatima benzaldehida dao derivate 2-benzlidenbenzo[b]tiofen-3(2H)-ona. Ostatak ovog završnog rada posvećen je analizi UV-Vis spektara sintetisanih jedinjenja