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Benthic diatoms have been used for decades as powerful indicators for biomonitoring lakes and rivers around the world. Due to the more than 100,000 diatom species morphological approach requires a high level of taxonomic knowledge. To overcome this obstacle, the application of metabarcoding has been developed in recent years. One of the challenges that still “forces” the simultaneous use of both approaches in biomonitoring is the incompleteness of the reference barcoding library. The diatom community from different substrates (reed, mud, artificial substrate) in Pečena Slatina has been intensively investigated in 2019, 2021-2023. One of the goals of the ongoing BIOLAWEB project, funded by the European Union, was to complement the Diat.barcode reference library for the possibility of using metabarcoding as tool in the future routine biomonitoring in Serbia. The morphological results show a similar diatom composition among different substrates with little difference in dominant taxa. Nitzschia frustulum was one of the most dominant taxa in 2022, while in 2019 it dominated together with Anomoeoneis sphaerophora, in 2021 with Navicymbula pusilla and Tryblionella hungarica, and in 2023 with Halamphora veneta. Molecular data (rbcL) have shown the dominance of T. hungarica and Nitzschia supralitorea. Anomoeoneis sphaerophora was observed in microscopy while metabarcoding data showed an unknown sequence of Anomoeoneis. Using phylogeny and p-distance calculations to compare our sequence to those present in the Diat.barcode we showed that this unknown sequence of Anomoeoneis had a high probability of matching with A. sphaerophora.

FETPY, an organo-diiron(I) complex, showed strong cytotoxicity across a panel of human and mouse cancer cell lines, combined with an outstanding selectivity compared to nonmalignant cells. Enhanced iron uptake in aggressive, low-differentiated cell lines, caused membrane lipid peroxidation, which resulted in ferroptosis in human ovarian cancer cells. FETPY induced significant morphological changes in murine B16–F1 and B16–F10 melanoma cells, leading to senescence and/or trans-differentiation into Schwann-like cells, thus significantly reducing their tumorigenic potential. Additionally, FETPY substantially suppressed tumor growth in low- and high-grade syngeneic melanoma models when administered in a therapeutic regimen. FETPY is featured by satisfactory water solubility (millimolar range), an amphiphilic character (Log Pow = −0.17), and excellent stability in a biological medium (DMEM). These important requisites for drug development are rarely met in iron complexes investigated so far as possible anticancer agents. Overall, FETPY holds promise as a safe and potent targeted antitumor agent.

Freshwater lakes have been heavily altered by multiple stressors for decades, including a wide range of harmful human activities. Similarly, it is estimated that most of continental saline lakes will have undergone changes in their functioning by 2025. In the European Water Framework Directive (WFD), the ecological status assessment of lakes is based on the survey of key communities (i.e., Biological Quality Elements, BQEs). Due to its ecological features, phytoplankton is one of the key BQEs required by the WFD. In current assessments, phytoplankton is studied using a standardised microscopy approach. The advent of methods based on molecular techniques (e.g., eDNA metabarcoding) provides an alternative to overcome issues associated with microscopy-based assessment. The aim of our study was to compare phytoplankton data obtained by microscopy approach with eDNA metabarcoding based on the 23S RNA marker gene. Water was sampled in eight sites: four sites in Savsko lake (urban freshwater lake) and four sites in Plava Banja (saline clay pit pond) during spring, summer, and autumn 2023. The water quality analyses showed that nutrient concentrations (especially total nitrogen), chlorophyl a and conductivity were several times lower in the freshwater lake than in the saline lake. The very high total dissolved mineral content in Plava Banja had a substantial impact on the phytoplankton composition The results of lake species inventories obtained using both approaches will be presented. Particular attention will be paid to the level of congruence between the fl oristic lists.

Charophyte algae have long been used for the ecological status assessment of lakes. Traditional fieldwork and species determination are, however, time-consuming and expensive. In the BIOLAWEB project, we aim to use environmental DNA (eDNA) for metabarcoding of Chara sp. in the water samples from selected lakes, and use this information to develop new or improve existing indices for the ecological status assessment of lakes. Ecological status assessment of lakes is important to safeguard biodiversity, and to ensure that lakes are in good enough status to safely be used for, among others, drinking water production, and recreation. Charophytes are benthic algae which are sensitive to changes in water quality and therefore are important indicators for ecological status. The use of eDNA is an approach that can be used to quickly detect the presence of different species in a lake, including species that are easily overlooked with more traditional, time-consuming methods. The use of eDNA for ecological status assessment is, therefore, a new and promising field of study. Here we present preliminary results of charophyte investigations in four lakes in Serbia, two freshwater and two saline lakes, in three seasons. Besides traditional sampling of charophytes, water samples were filtered for eDNA, aiming to generate new knowledge on the use of DNA metabarcoding for the detection of charophyte algae and for improving indices for ecological status assessment.

Propranolol, a beta-blocker, is a widely used drug for cardiovascular diseases. A synthetic sample containing propranolol (PRO) solution at native pH was recirculated up to ten times through an original coaxial non-thermal plasma reactor with a water falling film. Different discharge conditions, feed gasses, and power greatly influenced the extent of PRO degradation and the abundance of degradation products. The highest degradation rates were achieved in Ar plasma, either pure or in a mixture with O 2 , with over 70% of PRO degraded after only two passes through the DBD reactor. The full non-thermal plasma treatment was followed by a minimal change of pH value and conductivity. On the other hand, ambient air as the feed gas resulted in 60% of PRO degradation rate after the full treatment and contributed to a major drop in pH value and an increase in the conductivity of the treated solution. The structures of 47 degradation products in all three gases were identified and the degradation pathway is proposed, supported by DFT methodology. Scavenging experiments demonstrated that hydroxyl radical was predominant when plasma was generated using ambient air and Ar, while it had a minimal effect on the degradation in the mixture of Ar and O 2 . The desired level of propranolol decomposition was achieved only by the adjustment of the nonchemical parameters of the treatment, such as plasma gas composition and power. These results imply that a non-thermal plasma reactor is a highly effective method for pharmaceutical wastewater treatment, with no catalysts added.

Propranolol, a beta-blocker, is a widely used drug for cardiovascular diseases. A synthetic sample containing propranolol (PRO) solution at native pH was recirculated up to ten times through an original coaxial non-thermal plasma reactor with a water falling film. Different discharge conditions, feed gasses, and power greatly influenced the extent of PRO degradation and the abundance of degradation products. The highest degradation rates were achieved in Ar plasma, either pure or in a mixture with O2, with over 70% of PRO degraded after only two passes through the DBD reactor. The full non-thermal plasma treatment was followed by a minimal change of pH value and conductivity. On the other hand, ambient air as the feed gas resulted in 60% of PRO degradation rate after the full treatment and contributed to a major drop in pH value and an increase in the conductivity of the treated solution. The structures of 47 degradation products in all three gases were identified and the degradation pathway is proposed, supported by DFT methodology. Scavenging experiments demonstrated that hydroxyl radical was predominant when plasma was generated using ambient air and Ar, while it had a minimal effect on the degradation in the mixture of Ar and O2. The desired level of propranolol decomposition was achieved only by the adjustment of the nonchemical parameters of the treatment, such as plasma gas composition and power. These results imply that a non-thermal plasma reactor is a highly effective method for pharmaceutical wastewater treatment, with no catalysts added.

Due to the similar chemical properties of Ni2+ and Co2+, several dozens of adsorptive stripping voltammetric (AdSV) methods have been developed for their simultaneous determination. The question was would there be some benefits if a stripping method made for simultaneous determination of Ni2+ and Co2+ will be optimized for the determination of only one of them (Ni2+). It was found that the optimized method has for an order of magnitude lower LOQ (1.89×10−10 M), an order of magnitude lower influence of Co2+, and the applicability of one calibration line for four orders of magnitude of Ni2+ concentration. The influence of some common anions and cations has been examined. The developed method was successfully applied for nickel content determination in real samples. The suitability of the developed method for the determination of Co2+ from the same solution in the second run, upon optimizations of deposition potential and time, was also explored. The LOQ obtained for Co2+ (3.61×10−11 M) is almost two orders of magnitude lower than LOQ of the method for simultaneous determination of both cations and, its LOD and LOQ are among few lowest obtained by AdSV methods for Co2+ determination. The developed method for Ni2+ and Co2+ determination from the same solution in two successive runs has significantly better analytical performances than the starting method for their simultaneous determination in one run.

Project "Boosting Institute of Chemistry, Technology and Metallurgy in Water Biomonitoring" (BIOLAWEB) aims to strengthen the research and innovation capacity of the Institute of Chemistry, Technology and Metallurgy, National Institute of the Republic of Serbia, University of Belgrade (UB-ICTM) in biodiversity assessment and biomonitoring. UB-ICTM researchers made a noticeable contribution to the study of biodiversity, community ecology, and conservation of water bodies in South-Eastern Europe. However, a knowledge on index development and intercalibration following the EU standards for lakes and watercourse monitoring is still lacking in this geographic region. Similarly, there is a knowledge gap in DNA-based ecological status assessment in SEE.

Napredak u molekularnoj biologiji doveo je do snažnog razvoja molekularnih metoda u biomonitoringu. Metabarkoding je porcedura zasnovana na upotrebi DNK molekula koja može da dopuni ili čak potpuno zameni klasičan biomonitoring u skorijoj budućnosti. Sproveli smo istraživanje fitoplanktonske zajednice, važnog biološkog parametra kvaliteta, u Markovačkom jezeru sa ciljem da uporedimo tradicionalni i molekularni pristup u biomonitoringu. Ukupno smo pronašli 105 sekvenci algi i cijanobakterija, ali usled nepotpunosti baze, lista taksona dobijena metabarkodingom je nepotpuna. Iako se rezultati metabarkodinga trenutno ne mogu koristiti za procenu ekološkog statusa u Republici Srbiji, primena molekularnog pristupa u biomonitoringu je obećavajuća., The advancement in molecular biology resultet in development of molecular methods in biomonitoring. Metabarcoding is a DNA based procedure that can supplement or even replace classical biomonitoring in the near future. We conducted a study of phytoplankton, an importtant biological quality element, in Markovačko lake aiming to compare morphological and metabacoding approach in biomonitoring. In total, 105 sequences were obtained, but due to the incompletness of the reference library the metabarcoding taxonomic list was not comprehensive. Although, the metabarcoding results can not be currently used for ecological status assessment in the Republic of Serbia, its application in biomonitoring is promissing.