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Mining Waste Management in Serbia: Systemic Challenges and Reporting Deficiencies
No full textIn the total volume of non-hazardous waste generated in Serbia in 2023, non-hazardous mining waste
accounted for as much as 92.16%, while hazardous mining waste (HMW) represented 99.58% of the
total amount of hazardous waste generated nationwide [1]. Among 38 European countries, Serbia
recorded the highest quantities of both total mining waste (TMW) and HMW in 2022, amounting to
164.9 million and 29.7 million tonnes, respectively [2]. When it comes to mining waste management,
the 2022 report of the State Audit Institution of the Republic of Serbia (SAI) highlights that operators
often dispose of and manage mining waste without the permits required by law. Furthermore, the SAI
emphasizes the absence of an effective system for reporting and verifying the accuracy of data regarding
both the quantities and characteristics of the mining waste being generated [3]. At the time of writing
this paper, only two legal entities in Serbia possess valid permits for the management of HMW.
Specifically, one company is authorized to collect and transport all classified types of HMW, while the
second operator holds a permit for the storage and treatment of two specific types of HMW (waste
codes: 01 05 05 and 01 05 06) [4]. In light of the marked increase in the quantity of both TMW and
HMW in Serbia since 2022 (Figure 1) [5], it becomes evident that addressing this issue requires a
systemic, multidisciplinary approach. Such an approach must involve competent ministries,
professional and scientific institutions across the country, and the wider public
Позитрон - 35-36
No full textОвај блокадни двоброј започињемо тренутно најактуелнијом и најважнијом темом – текстом о блокади чији је аутор Јован Цветковић. Сазнајте како то најпознатија слика на свету, Мона Лиза, изгледа из угла хемичара од хемичарке Милице Бирманац. Даље се осврћемо на прошлогодишњи, 17. Фестивал науке, Нобелову награду из хемије за 2024. годину и манифестацију Global Women’s Breakfast одржан по четврти пут, а први пут уживо, у просторијама нашег факултета. Нешто више о једној од саговорница манифестације и оснивачици Позитрона, Ивани Вељковић, прочитајте у тексту из рубрике Алумнисти Хемијског факултета. У наредној рубрици, Пројекти на Хемијском факултету, разговарамо о пројекту New SMART Synthesis, којим руководи проф. др Радомир Н. Саичић. Након тога, разговарамо са др Ериком ван Хулебушом, редовним професором Биогеохемије инжењерских екосистема на Универзитету Paris Cité у Француској. Ако вас занима одакле Београду вода за пиће, одговор на то се налази у тексту о Макишу. Као и увек, на крају вас чека ретросинтеза, коју овај пут прати и блокадна ретросинтеза, у којој се присећамо свега што се десило на нашем факултету и у држави у последњих седам месеци. Уживајте
Enzimska i hemijska sinteza auronolignana
No full textKotinignani A i B su jedini do sada izolovani auronolignani, a izolovani su iz srži stabla biljke Cotinus coggygria. Spadaju u grupu flavonolignana i sastoje se iz auronskog i lignanskog dela. Značajna citotoksičnost i selektivnost kotinignana A na K562 ćelijskim linijama leukemije utvrđena u ranijim istraživanjima je bila motiv za sintezu auronolignana. U tu svrhu odabrane su sinteza iz aurona sulfuretina i sinapil alkohola katalizovana enzimom lakazom i hemijskom sintezom uz pomoć srebro-karbonata.
Cilj ovog rada bio je sineza auronolignana tipa izokotinignana i ispitivanje njihove citotoksičnosti.
Sintetisana su i okarakterisana dva izokotinignana, cis-izokotinignan A (1) i trans-izokotinignan A (2), i ispitana je njihova citotoksičnost
Pancreatin digestion of B-phycoerythrin from Porphyridium purpureum releases chromopeptides with inhibitory activity towards SARS-CoV-2 main protease
No full textUnique features of covalently attached tetrapyrrole chromophores give phycobiliproteins (PBPs) remarkable optical and bioactive properties with significant potential for application in the food industry, medicine, and biotechnology. This study investigated the potential of chromopeptides, released upon enzymatic digestion of major PBPs from cyanobacteria Limnospira platensis (C-Phycocyanin) and red microalgae Porphyridium purpureum (B-Phycoerythrin), to inhibit the main protease (Mpro) of SARS-CoV-2 virus. The digest obtained by pancreatin digestion of B-Phycoerythrin exhibits the highest inhibitory activity with estimated IC50 values in the low micromolar range. Mass spectrometry was used to determine the sequence of RP-HPLC-purified chromopeptides, and small peptides (2–7 amino acid residues) were identified. The inhibitory activity of purified chromopeptides confirmed that chromopeptides are the major components in B-Phycoerythrin digest and are responsible for Mpro inhibition. The binding of chromopeptides to Mpro was evaluated using molecular docking, while molecular dynamics simulations were employed to propose a plausible mechanism of Mpro inhibition.This is the peer-reviewed version of the article: Gligorijević, N., Radović, J., Radibratović, M., Đorđević, M., Spasić, D., Nedić, O., Nikolić, M., Minić, S.. (2025). Pancreatin digestion of B-phycoerythrin from Porphyridium purpureum releases chromopeptides with inhibitory activity towards SARS-CoV-2 main protease. Algal Research 2025, 91, 104274. [https://doi.org/10.1016/j.algal.2025.104274]Published version: [https://cherry.chem.bg.ac.rs/handle/123456789/7197]Supplementary material: [https://cherry.chem.bg.ac.rs/handle/123456789/7460
Facile prepared high purity Cerium vanadate for simultaneous electrochemical detection of p-nitrophenol and 2,4,6-trichlorophenol
No full textThe incomplete inner subshell (i.e., 4f) makes rare-earth elements (REE) different from other elements in the
periodic table. Incorporating an atomic number across the lanthanide group merely adds an extra electron to the
inner 4f rather than the outer shell. To prove this, we tested Nd and Ce doped vanadates as facile and convenient
way for simultaneous detection of para-nitrophenol and 2,4,6-trichlophenol via the electrochemical way over
modified glassy carbon (GC) electrode (GC/CeVO4; NdVO4). For the materials preparation convenient single-step
hydrothermal procedure was developed and resulting material (CeVO4) demonstrate high grade of crystallinity
with average size through the crystalline plain (200) equal to 57.4 nm and absence of any additional phases. GC/
CeVO4 electrode was applied for the pioneering study of simultaneous determination of p-nitrophenol (pNP) and
2,4,6-trichlorophenol (TCP) via the SWV method in Britton-Robinson buffer solution at pH5. The developed
method of evaluation demonstrate the span of p-nitrophenol calibration graph in range from 0.2 μM to 100 μM
with the detection limit 0.058 μM in the presence of 100 μM of 2,4,6-trichlorophenol. The TCP calibration graph
comprise concentrations in range from 0.2 μM to 60 μM with the detection limit 0.111 μM in the presence of 100
μM of pNP. Simultaneous determination of pNP and TCP may be performed in range from 0.2 μM up to 60 μM
with the limits of detection equal to 0.091 μM for pNP and 0.151 μM for TCP. GC/CeVO4 electrode demonstrate
9.2 % deviation of pNP signal and 11.3 % of TCP signal deviation within 8 cycles of measurement. Interference
study was held with K+, Mg2+, Sr2+, ascorbic acid, citric acid, urea, phenol, resorcinol each taken in 10-fold
excess, while the electrode demonstrated retention of signal level not less than 75 % of initial. Application of
electrode to tap water investigation had shown the 15 % deviation of pNP signal while the TCP signal stays
intact. The abovementioned makes GC/CeVO4 electrode promising for the evaluation of aromatics in
wastewaters
Sinteza i karakterizacija kompleksa Co(III) sa kondenzacionim proizvodom 2-acetiltiazola i semikarbazid hidrohlorida
No full textU ovom radu uspešno je sintetisan hidrazonski ligand (E)-2-(1-(tiazol-2-il)etilidin)hidrazin-1-karboksiamid (HL) kondenzacionom reakcijom 2-acetiltiazola i semikarbazida hidrohlorida u vodenom rastvoru pod blago kiselim uslovima. Struktura liganda potvrđena je IC, NMR i elementarnom analizom
Optimizacija elektroforetskih analiza glutenskih proteina i njihovih hidrolizata dobijenih našom proteazom
No full textCilj ovog istraživanja bio je optimizacija elektroforetskih metoda za analizu glutenskih proteina i
njihovih hidrolizata, kao i uspostavljanje metodologije za praćenje aktivnosti proteaza sa
potencijalom za razgradnju glutena. Gluten, složeni proteinski kompleks prisutan u pšenici, sastoji se
od glijadina i glutenina, koji zajedno određuju reološka svojstva testa, ali istovremeno predstavljaju
uzrok imunoloških reakcija kod osoba sa celijakijom i necelijakijskom osetljivošću na gluten. U tom
kontekstu, značajan interes usmeren je ka identifikaciji i primeni enzima, naročito mikrobioloških
proteaza, koji mogu selektivno hidrolizovati glutenske frakcije i time smanjiti njihov imunogeni
potencijal.
U okviru rada razvijene su i optimizovane metode SDS–PAGE i Tricine–SDS–PAGE za analizu
proteina i peptida male molekulske mase (<10 kDa). Kao uzorci korišćeni su pšenični gluten, glijadin
i glijadin tritikalea, dok je izvor enzima bio delimično prečišćen preparat bazne proteaze iz soja
Bacillus velezensis 16B
Agro-Residues and Sucrose Alternatives in Confectionery Transformation Towards Glucose Spikes Minimization
No full textApple and beetroot pomace flour (APF and BPF), along with two sweeteners, sucrose and a blend of sucrose substitutes (erythritol, stevia, inulin, and fructose), were simultaneously incorporated into three matrices formulated with agar, pectin, or gelatin as gelling agents. The aim was to produce jelly candies with high content of dietary fiber and dietary phenolics, and reduced energy value. The simultaneous incorporation of sucrose substitutes and pomace flour resulted in decrease of Carb:Fiber and Sugar:Fiber Ratio to extremely low values of 2.7–3.4 and 1.3–1.6 respectively, as well as in Energy:Fiber Ratio decrease to 9.2–12.3 kcal/g DF. Relative Antioxidant Capacity Index (RACI), as indicator of antioxidant potential, was calculated by assigning equal weight to Folin–Ciocâlteu, DPPH and FRAP assays applied upon in vitro digestion of 18 formulations of jelly candies. Results obtained for formulations with and without sucrose, as well as with and without APF or BPF, enabled insight into effects of pomace flour addition and sucrose substitution in each gelling matrix on functional properties. The incorporation and the substitution impact on postprandial glucose response were followed in vivo. Their superimposing resulted in glycemic index below 30 and low glycemic load. Efficiency of applied approach in functionalization of confectionery burden with energy and minimization of glucose spike represent an example of agro-residues re-introduction with the highest potential contribution to anti-obesity strategy
The first evidence of lumiphorbol as a metabolite of the Euphorbia species: Scientific paper
No full textEuphorbia nicaeensis All. belongs to the flowering plant family Euphorbiaceae. Our previous research has shown that the latex of this species is a rich source of jatrophane-type diterpenes. Due to the exceptional biological activities exhibited by these compounds, the research was extended to the root of this plant species. From the roots of E. nicaeensis, collected in Deliblato Sand (Serbia), a diterpene from an extremely rare class of lumiphorbol was isolated for the first time from Euphorbia species. The structure of the isolated compound was determined by spectroscopic techniques (1D- and 2D-NMR), as well as HRESIMS data
Opin dehidrogenaza poreklom iz Desulfohalobium retbaense – ispitivanje supstratne specifičnosti i delimična funkcionalna karakterizacija
No full textU okviru prethodnih istraživanja utvrđeno je da protein čija je sekvenca dobijena iz metagenomske analize genoma halofilne bakterije Desulfohalobium retbaense potencijalno može da ima aktivnost opin dehidrogenaze. U toku ovog istraživanja ovaj protein je heterologno eksprimiran u Escherichia coli, prečišćen, i delimično okarakterisan kako bi se stekao uvid u njegovu aktivnost i stabilnost. Na osnovu njegove aktivnosti u reakciji kondenzacije L-alanina i piruvata zaključeno je da pripada klasi alanopin dehidrogenaze. Ispitivani su optimalni uslovi za aktivnost enzima (pH i temperatura), kao i faktori koji utiču na stabilnost, kao što su uslovi za skladištenje prečišćenog enzima, pH i temperatura. Takođe je ispitana supstratna specifičnost enzima prema različitim donorima amino grupe i α-keto kiselinama. Enzim je pokazao širok spektar stabilnosti pri različitim uslovima, kao i preferencijalnu aktivnost ka aminokiselinama kratkog alifatičnog lanca. Ova saznanja doprinose razumevanju potencijalnih primena ovog enzima u stereoselektivnoj sintezi amina u hemijskoj i farmaceutskoj industriji