Stefan Petrović

Lemon balm (Melissa officinalis L.) is a well-established medicinal plant prized for its rich content of bioactive compounds. This study explored how artificial cadmium (Cd) contamination of soil affects the accumulation of heavy metal(oid)s, antioxidant activity, and the concentration of rosmarinic acid in lemon balm. At a soil Cd level of 20 mg/kg, plant growth was reduced, while the concentrations of most other elements, antioxidant activity, total phenolics, and flavonoids decreased, and the rosmarinic acid content increased slightly. In contrast, lower Cd levels (5 and 10 mg/kg) led to a modest increase in antioxidant activity and phenolic content. Cadmium accumulation in the aerial parts exceeded the WHO limit for medicinal plants. Although minor improvements in antioxidant properties were observed at lower Cd levels, and rosmarinic acid increased at 20 mg/kg, the health risks associated with Cd accumulation remain a concern. Therefore, monitoring Cd content in lemon balm grown on contaminated soils is essential to ensure its safe medicinal use.

The growing demand for agricultural products has led to the misuse of pesticides, resulting in the use of higher concentrations of these substances. This has led to an increase in toxicity imposed on other beneficial organisms and to the bioaccumulation of toxic pesticide concentrations in the bodies of both pests and non-target organisms, as well as in their end users, including humans. In this study, the neurotoxic potential of the commonly used pesticides abamectin (an insecticide) and boscalid (a fungicide) was evaluated. Both in vitro and in silico studies showed that human butyrylcholinesterase is not a target for abamectins B1A and B1B. Boscalid showed a modest Glide score (−28.8 kJ/mol) and a considerably higher IC₅₀ (308.8 µM) against human butyrylcholinesterase than the approved inhibitor (2-((1-(benzenesulfonyl)-1H-indol-4-yl)oxy)ethyl)(benzyl)amine (IC₅₀ = 0.473 µM). However, due to its non-mutagenicity and low toxicity, structural analogues of boscalid might be considered as candidates for the symptomatic treatment of Alzheimer’s disease. Molecular dynamics simulations over 100 ns confirmed the stability of boscalid within the active site of butyrylcholinesterase, where it maintained key interactions with catalytic residues such as Trp82 and His438. These findings highlight its potential as a starting point for structure-based drug design strategies aimed at optimizing cholinesterase inhibitors with improved pharmacokinetic properties. According to absorption, distribution, metabolism, elimination, and toxicity studies, boscalid is orally active, which cannot be attributed to abamectins B1A and B1B.

The optimized electrochemical method, cyclic voltammetry, was applied to investigate the antioxidant capacity of water extracts of Rosa canina L. fruits. Scan speeds (25, 50, and 75 mV/s) and pH (2, 4.5, and 7) were varied and optimal conditions were found at 75 mV/s and pH 4.5. Cyclic voltammograms, recorded from 0 to 1200 mV, showed anodic peaks for catechin-type flavonoids and quercetin. Spectrophotometric tests (FRAP, CUPRAC, DPPH, ABTS) and determination of total polyphenols content (TPC), total flavonoids content (TFC), and vitamin C content were also conducted. FRAP and CUPRAC values ranged from 0.534 to 0.710 mmol Fe/g dw and from 103 to 174 mg TE/g dw, respectively. ABTS values were in the interval from 566 to 623 mg TE/g dw, while DPPH values ranged from 113 to 188 mg TE/g dw. Total polyphenols content and total flavonoids content ranged from 24.0 to 38.9 mg GAE/g dw, and from 12.7 to 21.5 mg CE/g dw, respectively. The concentrations of vitamin C were in the interval from 2.78 to 3.67 mg/g dw. Pearson’s analysis showed good correlations between ABTS and DPPH (R² = 0.87), FRAP and DPPH (R² = 0.85), FRAP and ABTS (R² = 0.86), TPC and in vitro tests (0.5 < R² < 0.77), and TFC and in vitro tests (0.47 < R² < 1). For the purpose of classifying spectrophotometric tests for determining antioxidant activity, hierarchical cluster analysis was performed.

This study aimed to determine element profile of the rose species originating from Serbia. With respect to that, 52 fruit samples of six wild Rosa L. species (R. agrestis Savi, R. canina L., R. corymbifera Borkh., R. dumalis Bechst, R. myriacantha DC., and R. spinosissima L.) were assayed for element contents, after the optimization and validation of the inductively coupled plasma atomic emission spectrometric (ICP AES) method. The analytical performance of axial and radial views was evaluated using the Mg(II)/Mg(I) line ratio. Robust plasma conditions were achieved at the radio frequency (RF) power of 1150 W and nebulization gas flow (NBF) rate of 0.5 L min-1. The matrix effect was below 13% and the recovery, using certified reference material (LGC7162 strawberry leaves), was between 85.7% and 109% with the exception of Fe (76.4%). Rosa fruits were found to be richer in minerals such as K (4710-9850 mg kg-1), Ca (2650-5140 mg kg-1), P (532-1610 mg kg-1), Mg (402-1000 mg kg-1), Na (11.2-39.1 mg kg-1), Mn (6.8-64 mg kg-1), Fe (9.9-30 mg kg-1), and Zn (6.03-17.5 mg kg-1). Also, the fruits were found to have a higher content of Si (15.2-51.6 mg kg-1). Regarding toxic elements, the obtained results for Pb (0.035-0.0121 mg kg-1) and Cd (0.0027-0.0492 mg kg-1) are in accordance with the maximum levels in fruits established set by the Commission Regulation. The results of the present study indicate that the investigated Rosa species contain various minerals and could contribute to the daily dietary requirements for K, Ca, Mg, P, Na, Mn, Cu, Zn, and Fe, as well as be used in food and the food additive industry.

This study examines the concentration of essential minerals and toxic heavy metals in acacia honey samples collected in Serbia, highlighting their health implications and environmental influences. Among the 23 elements analyzed, calcium levels ranged from 38.35 to 1148.5 mg/kg, averaging 411.5 mg/kg, higher than previous findings for acacia honey, underscoring its nutritional value. Potassium averaged 208 mg/kg, consistent with the literature, whereas Na content was notably higher than the values reported in the literature. Zinc levels were higher than typical (average 11.57 mg/kg), likely due to pollution of acacia plant. Lead was the only detected toxic metal, with concentrations below the European safety threshold of 1 mg/kg. The findings highlight honey’s nutritional benefits and emphasize the need for monitoring environmental contaminants to ensure honey’s safety and quality.

Lemon balm is a plant widely used across various industries worldwide, and it contains a significant number of phenolic compounds that can positively affect human health. Given its extensive use today, this study determined the total polyphenols and flavonoid contents, antioxidant activities, rosmarinic acid content, and heavy metal(oid)s levels in the leaves of the pot-grown lemon balm. The heavy metal(oid)s content was compared with the maximum permissible concentrations for medicinal plants, as the World Health Organization (WHO) recommended. The results showed that all analyzed elements (As, Cd, Co, Cu, Zn, Mn, Ni and Pb) concentrations were within the recommended limits. The phenolic compound content of lemon balm was compared with literature data for wild-grown lemon balm samples.

In this paper, the influence of elevated concentrations of some metal(oid)s (As, Cd, Co, Cr, Cu, Mn, Ni, Pb, and Zn) in the soil on the content of chlorophyll a, chlorophyll b, and carotenoids in leaves of national hybrids of pepper (Bela Duga) and maize (ZP606) was investigated. The results show the most pronounced negative effect of Mn and Pb on pepper, and Mn and Ni in the case of maize. The obtained results can serve in the discussion and better understanding of the potential of pepper and maize to deal with elevated concentrations of these metal(oid)s in the soil and their negative effects on plant growth and development.

Pesticides commonly used in the Republic of Serbia (tebuconazole, pendimethalin, pyraclostrobin, propiconazole and famoxadone) have high stability, so their potential toxicity to humans needs to be investigated. These pesticides are in use in the Republic of Serbia in various formulations. Their toxicity and interactions with acetylcholinesterase were thoroughly investigated in this study using computational tools. The ADMET (adsorption, distribution, metabolism, excretion, toxicity) study showed that all of them are efficient oral compounds, and that pendimethalin was a mutagenic compound. Glide scores ranged from ?18.41 (pendimethalin) to ?27.61 kJ mol-1 (famoxadone) in Mus musculus, and from ?19.58 (pendimethalin) to ?24.31 kJ mol-1 (propiconazole) in Homo sapiens. In addition, the experimental stability of the pesticides solutions in methanol was studied using the fast gas chromatography?mass spectrometry (GC?MS, retention times of the studied pesticides ranged from 14.47 (pendimethalin) to 22 min (famoxadone)). They showed good stability over time, apart from pyraclostrobin which decomposed mainly into its desmethoxy derivative after 20 months. Based on the promising modelling results, pyraclostrobin and famoxadone emerge as potential candidates for further investigation in the treatment of Alzheimer?s disease, taking care to increase their stability.