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Element profile and health risk assessment of wild Cornelian cherry (Cornus mas L.) collected in Bosnia and Herzegovina
No full textThe elemental composition of different parts of the Cornelian cherry (fruit flesh, pit, leaf, and bark) was analyzed using the ICP-OES method. Macroelements (Ca, K, Mg, Na, P, S), microelements (B, Co, Cu, Cr, Fe, Li, Mn, Ni, Se, Si, Sr, Zn), and toxic elements (Al, As, Ba, Cd, Pb) were analyzed. The highest concentrations of Ca (10,818.04–24,901.29 mg/kg), Mg (1903.77–3558.87 mg/kg), S (2193.67–3284.59 mg/kg), and P (3655.34–5959.26 mg/kg) were determined in the leaves. S was also present in significant concentrations, and K was highest in the fruit flesh (6598.00–8967.40 mg/kg). Higher concentrations of Fe, Mn, and Zn were determined in the leaves and bark, while the fruit flesh had lower concentrations of these elements (Fe: 7.17–337.05 mg/kg; Mn: 0.66–1.19 mg/kg; Zn: 2.70–3.83 mg/kg). B (to 24.09 mg/kg), Si (to 468.99 mg/kg), Li (to 1.44 mg/kg), and Sr (to 76.00 mg/kg) were most abundant in leaves and bark. The highest concentration of the toxic metal Al was detected in the leaf sample from Mostar (373.49 mg/kg). Cd and Pb revealed the lowest concentrations, below the detection limit (< 0.01 mg/kg), in several pit and flesh samples collected from Tuzla, Bijeljina, and Mostar. As levels were below 0.01 mg/kg in all analyzed samples. The differences in element concentrations may be related to different geochemical and ecological conditions characteristic of the collection areas, indicating a complex environmental influence on the bioaccumulation of elements in Cornelian cherry. In this study, an assessment of the potential health risks associated with the presence of heavy metals was conducted. The obtained Target Hazard Quotient (THQ) results for As, Cd, Pb, Cu, Zn, Ni, and Cr were lower than the safe limit, while Carcinogenic Risk Index (CRI) analysis indicated that Cd and Ni were the most important pollutants in the analyzed samples
Monoselective Alkylation of Primary Amines Under Simple Conditions: Only Amine and Alkyl Bromide in the Reaction Vial
No full textSelective alkylation of primary amines is an important chemical transformation because amines are constituents of natural products, pharmaceuticals, agrochemicals, and are important synthetic intermediates. We have shown that selective monoalkylation can be achieved using simple equipment and reaction conditions: amine and alkyl bromide in a 3:1 molar ratio in a reaction vial, heated in a laboratory oven if necessary. The scope of the reaction was investigated using various primary, secondary, and tertiary bromides and amines having nitrogen attached to primary, secondary, and tertiary carbon atoms. In the case of the aromatic amine, the reaction was carried out on silica gel in the solid state. Monoselectivity ranges from 53/47 to 100/0 and yield of secondary amines from 24%–87%
Effect of distillation method on the antimicrobial potential and composition of Roman Chamomile (Chamaemelum nobile (L.) All.) essential oil and hydrolate
No full textRoman chamomile is a perennial herbaceous plant that has been widely cultivated for its medicinal and ornamental properties. This study investigated the chemical composition, sensory properties, and antimicrobial potential of essential oils (EOs) and hydrolates (HYs) extracted through steam distillation (SD) and hydro-distillation (HD) from Roman chamomile grown in Serbia. GC-MS analysis showed that EOs were rich in esters such as isoamyl tiglate (21.1-32.5%) and isobutyl angelate (28.5-35.7%), while HYs contained trans-pinocarveol (20.9-22.7%) and pinocarvone (14.8-19.5%) as dominant compounds, with concentrations varying depending on the extraction method. These differences influenced sensory properties and were clearly distinguished in a PCA biplot. In general, the EOs exhibited a strong herbal and spicy aroma with floral, fruity, and minty undertones, while the HYs displayed a herbal scent with minty, ethereal, and green notes. Additionally, the antimicrobial, antibiofilm, and antiadhesion activities of the samples were evaluated against pathogens, including Salmonella enterica serovar Typhimurium, Escherichia coli, Pseudomonas aeruginosa, Enterococcus faecalis, E. hirae, Staphylococcus aureus, and S. epidermidis. Results showed that EOs exhibited strong antimicrobial activity, with inhibition zones up to 40 mm and MIC values using diluted EOs, while HYs had no significant effects. Multivariate and in silico analyses indicated that the antimicrobial activity of EOs is likely due to the synergistic effects of fatty acid esters, which also contribute to their pleasant aroma and potential for cosmetic use. In contrast, the aroma compounds in HYs were not associated with antimicrobial properties. Since HYs are largely by-products of EO extraction, further research is needed to explore their biological activities and potential applications
Impact of project-based teaching of natural sciences on key 21st century skills that contribute to students’ scientific literacy: A meta-analysis study
No full textPISA testing results indicate that Serbian students have an unsatisfactory level of scientific literacy which is essential for successful adaptation to life changes caused by fast scientific growth in the 21st century. As creativity, critical thinking, and science process skills represent key 21st century skills that contribute to students’ scientific literacy, the present study aimed to determine whether project-based teaching of natural sciences could be used for their enhancement. The three research hypotheses stating that the project-based approach is more effective than the traditional approach to teaching of natural sciences in promoting students’ creativity (H1), critical thinking (H2), and science process skills (H3) were evaluated through meta-analysis. The meta-analysis encompassed 32 studies published between 2004 and 2024, whose results enabled the calculation of 35 Hedge’s g values. Following the application of the random effects model, the weighted mean Hedge’s g value higher than +1.000, which indicates a strong positive effect of the project-based approach, was obtained for each hypothesis. Consequently, it was concluded that all hypotheses posed in this study are correct, which confirms the high effectiveness of the project-based teaching of natural sciences in terms of the promotion of the key 21st century skills that contribute to students’ scientific literacy
Bacillus velezensis: a natural shield against black rot disease on Serbian autochthonous cabbage cv. Futoški
No full textSerbian autochthonous cabbage cv. Futoški is highly susceptible to the plant pathogenic bacterium Xanthomonas campestris pv. campestris, the causal agent of black rot, leading to significant economic losses. This study aimed to isolate indigenous Bacillus spp. and Pseudomonas spp. strains with beneficial traits for biocontrol of black rot. From a total of 115 potential antagonistic strains, four (coded as P-FC 55, RD-FC 88, R-FC 102, And R-FC 114) identified as species Bacillus velezensis were selected as candidates based on strong in vitro antagonistic activity, both as whole cultures and cell-free supernatants, against the most virulent X. campestris pv. campestris strain (XcFC 231) identified in this study. No statistically significant differences were observed between the efficacy of whole cultures and supernatants of biocontrol candidates. Preventive inoculation approaches (seed and foliar) of biocontrol candidates consistently outperformed curative treatments across all strains, highlighting their potential as preferred application strategies. The most effective B. velezensis strain was RD-FC 88, applied in the form of a whole culture during preventive foliar application, achieving 93.86% disease suppression, surpassing copper oxychloride (89.26%) under the same conditions. Chemical profiling (GC/MS and UHPLC–QToF MS) of ethyl acetate extracts revealed the presence of a wide range of antimicrobial organic compounds (e.g., 2,3-butanediol, urea, succinic acid, thymine, phenylalanine, 9H-purin-6-ol) and lipopeptides (surfactins C12–C17), which may be contributing factors to the biocontrol activity of the strains. Next to the surfactins, molecular screening for the presence of genes encoding the production of lipopeptides with antimicrobial activity indicated the potential of strains to produce bacillomycin D and iturins (except R-FC 114) under certain growing conditions. Preventive application (seed and foliar) of biocontrol candidate strains led to an increase in epidermal flavonoid and chlorophyll content, while the opposite trend was observed in curative treatments. The results of this study highlight the strong potential of the B. velezensis strains P-FC 55, RD-FC 88, R-FC 102, And R-FC 114 for controlling black rot disease on the cabbage cv. Futoški, with possible broader applicability to other cabbage cultivars and Brassicaceae crops
Zn(II) and Cd(II) Complexes with a Thiazolyl-Hydrazone Ligand: Structural and Biological Insights
No full textSince the discovery of cisplatin, metal-based complexes have garnered considerable attention within the scientific community due to their promising therapeutic potential and broad spectrum of biological activities.[1] In this study, four Zn(II) and Cd(II) complexes with a pyridine-based thiazolyl-hydrazone ligand (HL) were synthesized and characterized both in the solid state and in solution. The obtained complexes include two cationic species, [Zn(HL)2](NO3)2·MeOH·H2O (Zn–1) and [Cd(HL)2](NO3)2·H2O (Cd–1), and two neutral complexes [ZnL2] (Zn–2) and [CdL2] (Cd–2) (Figure 1), all of which were isolated as single crystals. The investigation focuses on the influence of the central d¹⁰ metal ion [Zn(II) vs. Cd(II)] and the role of counterions from the starting metal salts (nitrate vs. acetate) on the structural features of the resulting complexes. Additionally, the study evaluates the impact of metal coordination on the antiproliferative and antimicrobial properties of the compounds. The deliberate selection of Zn and Cd metals with markedly opposing toxicity profiles enables a comparative evaluation of how the intrinsic nature of the metal center and its coordination environment influence structure-activity relationships. While Zn(II) is generally regarded as biocompatible and essential for numerous physiological processes, Cd(II) is well-known for its high toxicity. This contrast provides a valuable framework for understanding the role of metal identity in modulating the biological behavior of coordination compounds. These findings contribute to a deeper insight into the design principles of metal-based therapeutics, particularly in balancing efficacy and safety
Exploring the Sustainable Cosmetic Potential of Illyrian Iris Rhizome
No full textObjective This study aimed to provide the first comprehensive chemical and bioactivity profile of the eastern Adriatic endemic Illyrian iris (Iris pallida subsp. illyrica (Tomm. ex Vis.) K.Richt) rhizome, stored for 12 months post-harvest, using both conventional and greener extraction methods. The chemical composition of the essential oil was determined by gas chromatography-mass spectrometry (GC/MS), while ultra-high-performance liquid chromatography-diode array detector-tandem mass spectrometry (UHPLC-DAD-MS/MS) and high-performance thin-layer chromatography (HPTLC) were employed for metabolic fingerprinting of the extracts obtained. Additional HPTLC bioautography assays (HPTLC-DPPH/HPTLC-Tyrosinase) were conducted to explore their antioxidant and enzyme-inhibitory activities. The overarching goal was to assess the potential of this underexplored subspecies for sustainable cosmetic applications.
Methods HPTLC was performed in normal-phase mode using a mobile phase of ethyl acetate: toluene: formic acid: water (16:4:3:2, v/v/v/v) for optimal separation of compound classes. Post-chromatographic derivatization was performed using 0.5% NP and 5% PEG (w/v) and AlCl₃ for phenolic profiling, panisaldehyde for terpenoids, 0.1% methanolic DPPH for antioxidant screening, and L-DOPA/tyrosinase for bioautographic assays. Chromatographic separation of the extracts was carried out using UHPLCDAD- MS/MS for metabolic fingerprinting, while GC/MS and GC/FID were employed for the analysis of essential oils from Illyrian iris rhizome. Cell viability of HaCaT keratinocytes was assessed using the MTT assay after treatment with rhizome extracts.
Results GC/MS analyses of Illyrian iris rhizome essential oil, known as iris butter, identified myristic acid (75.8%), α-irone (9.2%), and silphiperfol-5-en-3-one B (2.2%) as major constituents. UHPLC-DADMS/ MS profiling revealed diverse phenolics, xanthones, and benzophenone derivatives. Acetone (AC) and ethanol (ET) extracts shared similar chemical and HPTLC profiles, marked by iriflophenone hexoside, mangiferin, and irigenin isomer. The highest radical scavenging potential was observed in AC and ET extracts. AC and ET extracts showed the most potent tyrosinase inhibition potential. MTT assays on HaCaT cells showed that the glycerol extract exhibited high biocompatibility, while the water extract induced marked cytotoxicity.
Conclusion Illyrian iris rhizome exhibits a rich and diverse phytochemical profile, with notable antioxidant and tyrosinase-inhibitory activities that support its potential for cosmetic applications. The study highlights the impact of extraction and storage on the chemical composition and reports, for the first time, the presence of a silphiperfol-type sesquiterpenoid in this endemic, underscoring its bioactive potential and the need for sustainable cultivation and further research
High-performance thin-layer chromatography–chemometric approach for the forensic discrimination of ballpoint pen ink samples collected in Serbia
No full textWith the aim of developing a model suitable for forensic ink analysis and establishing a comprehensive basic library of ink profiles available on the local market, a robust methodology involving high-performance thin-layer chromatography (HPTLC), image processing and chemometrics was developed, marking the first systematic investigation of blue ballpoint pen inks in Serbia for forensic purposes. In total, 18 blue ink samples were analysed under optimised extraction and chromatographic conditions, generating unique chromatographic profiles that revealed compositional differences. HPTLC profile plots, showing the dependence of colour intensity as a function of distance, form the basic ink library of reference samples against which the profiles of disputed samples could be compared. Principal component analysis classified inks into single-pigment and complex-pigment formulations. Key components differentiating inks were identified through loadings plots. The proposed protocol was additionally verified on a dispute document. This study establishes the basic and foundational library and reproducible HPTLC-based methodology, advancing forensic ink analysis in Serbia
Zeleni ekstrakti ljuske luka kao funkcionalna komponenta alginatnih biofilmova za očuvanje svežine voća
No full textCilj ovog rada bio je da se izvrši ekstrakcija biološki aktivnih jedinjenja iz ljuske crnog, belog i crvenog luka korišćenjem ekološki prihvatljivih („zelenih“) rastvarača, kao i da se dobijeni ekstrakti inkorporiraju u alginatne biofilmove namenjene produženju svežine i zaštiti voća. Kao zeleni rastvarači korišćene su prirodne eutektičke smeše (Natural Deep Eutectic Solvents, NADES), formirane kombinacijom L-prolina i polihidroksilnih alkohola. Ljuske luka odabrane su kao sirovina zbog visokog sadržaja biološki aktivnih jedinjenja i potencijala za njihovo ponovno korišćenje. Antioksidativna aktivnost dobijenih eutektičkih ekstrakata određena je primenom DPPH· i fosfomolibdenskog eseja, dok je antimikrobna aktivnost ispitana disk–difuzionim testom u agaru. Najaktivniji ekstrakti inkorporirani su u rastvor alginata radi formiranja biofilmova na bazi NADES-a, koji su dalje korišćeni kao premazi za voće (grožđe i breskvu), s ciljem procene efikasnosti u produženju roka trajanja. Rezultati su pokazali da biofilmovi sa dodatkom ekstrakta crvenog luka najefikasnije doprinose očuvanju kvaliteta grožđa, dok se kod breskve takav efekat nije uočio. Ovakav pristup predstavlja značajan korak ka razvoju održivih i ekološki prihvatljivih ambalažnih materijala, koji bi mogli zameniti sintetičke dodatke u prehrambenoj industriji
Regulation of immune cell metabolism by therapeutic normal IgG intravenous immunoglobulin
No full textImmune cell metabolism and metabolic end products influence the nature and magnitude of immune responses. Various autoimmune and inflammatory diseases are associated with dysregulated cellular metabolism. Intravenous immunoglobulin (IVIG), a therapeutic pooled normal IgG, is extensively used for the immunotherapy of a wide range of autoimmune and inflammatory diseases. Although several cellular and molecular mechanisms of action of IVIG have been reported, the role of IVIG in modulating the immune cell metabolism remains unknown. Objective: We sought to investigate the influence of IVIG on the metabolic events of human immune cells. Methods: We performed metabolic flux analyses on inflammatory mediators–stimulated human PBMCs. Furthermore, intracellular metabolites were extracted from activated PBMCs and subjected to liquid chromatography coupled to high-resolution mass spectrometry. Untargeted global metabolic profiling of PBMCs was performed to determine the metabolic landscape of immune cells and metabolic reprogramming by IVIG. Untargeted lipidomics was used for the mechanistic studies on IVIG-induced lipogenesis