Frankincense resin (Boswellia serrata), native to arid regions of India, the Middle East, and parts of Africa, has been highly valued for its medicinal properties. This study evaluated the antimicrobial potential of methanolic extracts of Boswellia serrata resin against Staphylococcus aureus, Pseudomonas aeruginosa, and Listeria monocytogenes. High-performance thin-layer chromatography (HPTLC) coupled with bioautography identified bioactive zones, while Liquid Chromatography–Mass Spectrometry (LC-MS) quantified the phenolic and terpenoid compounds. The cytotoxicity was assessed on HaCaT human keratinocyte cells to evaluate the safety for dermatological applications. The results demonstrated significant antibacterial activity, particularly against S. aureus and L. monocytogenes. The bioautograms revealed that samples from central and southern Serbia showed the highest antimicrobial effect against the tested bacterial strains. The active compounds included 11-keto-β-boswellic acid (up to 3733.96 μg/g), gallic acid (110.93 μg/g), and naringenin (53.13 μg/g). Cytotoxicity assays confirmed non-toxic effects at 10 µg/mL, with sample 6 enhancing the keratinocyte viability by 137%, while higher concentrations (50 µg/mL) showed variable cytotoxicity. These findings highlight the potential of B. serrata resin as a natural antimicrobial agent, particularly against antibiotic-resistant pathogens. Its therapeutic applicability in pharmaceutical and cosmetic formulations is promising provided that dosing ensures a balance between efficacy and safety.

Barbiturate derivatives were evaluated for their parameters of biological activity by applying linear regression and two multivariate methods (Cluster analysis and Principal component analysis). The lipophilicity of the studied barbiturates was determined on the modified carriers C18 in mixtures of water and four organic modifiers separately (methanol, n-propanol, acetone and tetrahydrofuran) by performing reversed phase thin layer chromatography and by applying relevant software packages. Chromatographic and computational lipophilicity of the examined barbiturates was correlated with the selected pharmacokinetic and toxicological predictors and good relationships were obtained. More concrete results were obtained by multivariate methods which showed that the polarity of the substituent has the greatest influence, and its electronic effects to a lesser extent on the tested parameters of the barbiturate derivatives. Results obtained by multivariate methods also suggest that the chromatographic retention constant, R_M⁰, shows a greater resemblance to the parameters of lipophilicity. The chromatographic parameter m, exhibits better agreement with the toxicity parameters.

The substituent and solvent effects on solvatochromism in 3-[(4-substituted) phenylamino]isobenzofuran-1(3H)-ones were studied using experimental and theoretical methodologies. The effect of specific and non-specific solvent?solute interactions on the shifts of UV?Vis absorption maxima were evaluated using the Kamlet?Taft and Catal?n solvent parameter sets. The experimental results were studied by density functional theory (DT) and time-dependent density functional theory (TD-DFT). The HOMO/LUMO energies (EHOMO/ELUMO) and energy gap (Egap) values, as well as the mechanism of electronic excitations and the changes in the electron density distribution in both ground and excited states of the investigated molecules were studied by calculation in the gas phase. The electronic excitations were calculated by the TD-DFT method in the solvent methanol. It was found that both substituents and solvents influence the degree of ?-electron conjugation of the synthesized molecules and affect the intramolecular charge transfer character.

The optimized methods for N-alkyl and N,N-dialkyl substituted thioureas synthesis starting from ammonium thiocyanates, waste water constituent from the production of tetramethylthiuram monosulfide (TMTS), and alkyl amine, are presented in this work. Therefore, thioureas synthesis was developed in two ways: Method I - reaction of the thiocyanate and alkylamine in the presence of hydrochloric acid; Method II - reaction of the thiocyanate with benzoyl chloride following by amine addition in the first step, and base hydrolysis in the second step. The structure of the synthesized compounds was confirmed by IR, 1H and 13C NMR and MS instrumental methods, and purity was determined by high-performance liquid chromatography method. It is shown that the proposed methods offer a high degree of conversion and purity of product, absence of by-products and technological applicability at industrial scale. Considering importance of the tetramethylthiuram disulfide (TMTD) and TMTS as vulcanization accelerators as well as thiourea as the pharmacologically active compounds, it can be said that application of the optimized methods of thiourea synthesis will provide significant improvement in sustainable development and implementation of eco-friendly production technology. The described, environmentally benign process of thioureas synthesis, represent a suitable option to existing methods.

Among numerous global problems, one of the most significant is air pollution. In this paper, unwashed (U) and water-washed (W) needles of two conifers—European larch and Douglas fir—were used to assess their capacity for the retention and accumulation of heavy metals. The needle samples were used to represent the atmospheric deposition of heavy metals located on the surface of the needles. The sampled European larch and Douglas fir plantations were situated at three locations in Serbia: a least polluted (Kučevo), a moderately polluted (Avala), and a very polluted (Lazarevac) site. The content of five heavy metals (Ni, Cu, Co, Cd, Pb) was investigated in the study. The concentration of cadmium (Cd) was higher in the European larch needles compared to Douglas fir, while the differences in the content of the other heavy metals between the species studied were insignificant. For both species, the following trend applied with respect to the heavy metal content in their needles: Ni ˃ Cu ˃ Co ˃ Pb ˃ Cd. Based on the results obtained, we deduced that the concentrations of all investigated heavy metals at all three locations for both species were within the allowed limits, except for nickel (Ni) content, which was over the predicted limit values for both species in the highly polluted area (Lazarevac). A PCA (principal component analysis) undertaken suggests that European larch has a greater ability to accumulate Co than Douglas fir on sites contaminated with heavy metals. The predictive foliar metal accumulation index (MAI) value was slightly higher in Douglas fir (4.14) than in European larch (3.76); therefore, the results suggest that this species would be a good planting choice, particularly in urban and industrial environments.