Journal of the Serbian Chemical Society

Biochanin A formulation with electrospun poly(vinylpyrrolidone) fibers and possible applications

2025-12-16T10:58:29+01:00

The aim of this paper is to examine the possibility of using electrospun poly(vinylpyrrolidone) (PVP) fibers as a carrier of the phytoestrogen biochanin A (BCA). PVP fibers were prepared with different BCA content by using electrospinning method at specific process parameters. Produced electrospun PVP–BCA fibers were characterized by chemical, physical-mechanical and biological methods. SEM, DSC and FTIR analyzes showed that there are no strong interactions between PVP and BCA molecules, neither thermal changes in tested temperature range (50–250 °C) and that equal distribution of BCA in the PVP electrospun fibers was achieved. Physico-mechanical tests showed that the physical properties and wetting angle of PVP change in the presence of BCA. Testing of electrospun PVP fibres with and without BCA on L929 fibroblasts in direct contact assay in vitro revealed a significant effect on proliferation and migration of fibroblasts. Biological tests confirmed that the system of electrospun PVP–BCA fibers can become suitable for the treatment of complicated wounds, where in the first stage of treatment the damaged tissue should be removed by the activity of electrospun PVP–BCA fibers. Another possibility of using electrospun PVP–BCA fibers is for the treatment of facial skin for the exfoliation intent.

Application of Floquet theory and improvement of electron current flow control in a 1D Fe–Cu molecular chain

2026-03-17T12:16:56+01:00

In this study is investigated the application of Floquet theory to a one-dimensional (1D) Fe–Cu molecular chain under periodic driving. It was demonstrated that orbital hybridization induces resonant behavior in the low-frequency regime, highlighting the potential of this system for energy-efficient and robust device applications. For the first time, a Floquet electronic friction framework – incorporating the influence of periodic driving on electron transfer – is applied to a 1D Fe–Cu molecular chain in the presence of strong light–matter interaction (LMI). Electron transport properties are analyzed, revealing the existence of an optimal driving frequency that maximizes the electric current. Two mechanisms for enhancing charge transport in the strong LMI regime are identified: a) hybridization-induced resonances and b) photon-assisted transport processes. In this work is combined Floquet band structure analysis with open-system transport modeling in a 1D Fe–Cu motif, revealing the impact of hybridization and periodic driving, on the enhancement of electron transport via photon-assisted resonances – an approach that bridges quasi-energy spectra and dissipative transport in a single theoretical framework. These findings provide new insights into driven low-dimensional transition-metal systems and may support the development of Fe–Cu-based materials for electrochemical applications.

In silico evaluation of phycobilins as multi-target anti-tubercular scaffolds: Molecular docking, dynamic stability, ADMET and mycobacterial sensitivity analysis

2026-01-30T10:22:14+01:00

Tuberculosis remains a major global health burden, highlighting the urgent need for novel therapeutic scaffolds with imbproved efficacy and multi-target activity. In this study, an integrated in silico strategy was used to investigate the anti-tubercular potential of four naturally occurring phycobilins – phycocyanobilin, phycoerythrobilin, phycourobilin and phycoviolobilin – against a panel of essential Mycobacterium tuberculosis protein targets involved in cell wall biosynthesis, nucleic acid metabolism, energy production and ribosomal function. Molecular docking analyses revealed consistently strong binding affinities of phycobilins toward multiple targets, often exceeding those of isoniazid and approaching the binding performance of rifampicin, indicating pronounced multi-target interaction capability. Noncovalent interaction analysis showed stable and diverse interaction networks dominated by hydrogen bonding and hydrophobic contacts. Normal mode analysis confirmed that phycobilin binding preserves intrinsic protein dynamics while inducing ligand-mediated stabilization of the protein–ligand complexes, particularly for the phycoviolobilin–InhA system. Pharmacokinetic and toxicity predictions suggested moderate distribution properties and generally favorable safety profiles, although potential mutagenicity and skin sensitization signals were identified. Additionally, mycoCSM-based predictions indicated micromolar-range anti-mycobacterial activity with limited penetration into caseous lesions. Collectively, these results support phycobilins as promising natural scaffolds for anti-tubercular drug discovery, warranting further optimization and experimental validation.

Modelling and optimisation of the activated sludge process using artificial neural networks and genetic algorithms

2026-02-09T15:21:41+01:00

Mathematical modelling of the activated sludge process (ASP) was performed using multi-layer perceptron neural networks (MLP-ANN) to predict effluent water quality parameters and multi-objective genetic algorithm (MOGA) was employed to optimise influent water quality parameters so that the concentration of contaminants in the effluent stream is minimised. The study area selected was located in a central district of a southern state of India. The effluent parameters to be investigated and optimised are pH, suspended solids (SS) and biochemical oxygen demand (BOD) and oil and grease (O&G). The model was evaluated based on the statistical parameters of the correlation coefficient R and the mean square error (MSE). MATLAB R2019a was used for the modelling and optimisation study. It has been found that effluent pH, SS and BOD were predicted with an overall R of 0.9207 and an MSE of 0.0091. During optimisation of influent parameters, it was found that optimum values of the decision variables pH_Inf lie between 6–8, optimum values of SS_Inf lie between 68–380 mg L^-1, optimum values of BODInf lie between 155–692 mg L^-1 and optimum values of O&GInf lie between 8–45 mg L^-1 when the objective functions were minimised simultaneously.

DFT-guided prediction of singlet fission chromophores for high-eﬃciency organic solar cells

2026-01-22T13:48:55+01:00

Theoretical design and DFT calculations were performed to find new SF chromophores to be used in high efficiency organic solar cells. These included 6 new compounds containing boron, nitrogen, selenium, TIPS and phenyl groups. All of these molecules demonstrated near-planar geometries with extended π-conjugation and had HOMO–LUMO gaps between 3.04 and 3.32 eV. The excitation energies for the singlet and triplet states were in the ranges of 2.11–2.25 eV and 1.00–1.10 eV, leading to singlet–triplet energy gaps ranging from 1.11–1.16 eV. All compounds met the critical energetic requirement for efficient singlet fission whereby E_S1 > 2E_T1 for all chromophores. Some selected derivatives, such as N1 and N4 were found to have ΔE_ST values of 1.15 and 1.14 eV, respectively, which are equal to or greater than the benchmark value of pentacene which is 1.02 eV and diketopyrrolopyrrole which is 1.18 eV. Moreover, the new chromophores are expected to have greater absorption and thermal stability spectrum making them better suited for next-generation organic solar cells. This study highlights the promise of rational heteroatom and functional group design for SF-active materials with advanced optoelectronic and device-engineering properties.

Seasonal influence on suitability of masquerade tree as a bioindicator of vehicular pollution along University of Ilorin Road, Nigeria

2025-10-02T11:36:00+02:00

This study focused on the seasonal impacts on the suitability of masquerade (Polyalthia longifolia) as a bioindicator of vehicular pollutants. Some leaves of the tree were plucked along the roadside and from a control site with no vehicular emissions. Biochemical parameters, including pH, ascorbic acid content, relative water content, total chlorophyll and air pollution tolerance index (APTI), were determined in both dry and wet seasons using standard methods. Potentially toxic elements (PTEs) commonly associated with automobile pollutants (Pb, Zn, Cr, Mn, Fe and Cu) were analyzed using atomic absorption spectroscopy, after acid digestion. The concentrations of PTEs were slightly higher in leaves from roadside masquerade tree than in those from the control site, except for Cr and Cu at some sampling points during the wet season. The biochemical properties in the roadside samples indicated the presence of pollutants compared to the control site in both seasons. APTI of the roadside samples showed higher sensitivity (mean value = 10.30) in the dry season, indicating a gradual loss in tolerance to pollution; however, a slight increase (mean value = 11.23) in tolerance was observed in the wet season. The masquerade tree demonstrated its sensitivity to vehicular pollution in both seasons. It is more sensitive in the dry season but tends to tolerate pollutants in the wet season by increasing APTI through improved defense mechanisms.

Comparative assessment of adsorbents performances of plant biomasses grown on different sites: Case study of invasive Acer negundo L.

2025-07-15T18:31:18+02:00

With the increasing global spread of invasive species, collecting their biomass could be a promising source for adsorbent development and water remediation. Therefore, the ability of adsorbent based on biomass of invasive plant Acer negundo L. originating from different habitat types was investigated for the lead removal from aqueous solution, in order to observe if different growing sites have effect on adsorbent performances. Three sites were selected for sampling: forest edges on Mt. Avala, riparian forests at Great War Island and banks of coal separation pond in Piskanja, Serbia. Characterisation was performed via pHpzc, zeta potential, cation exchange capacity, SEM-EDS and FTIR analysis. Optimization of sorption parameters was done and the best performance was at pH 5.0, adsorbent dosage 2.0 g/dm³ at 298 K for 60 min. Fitting of isothermal experiment data showed best correlation with Sips model (q_max is 94.92–131.52 mg/g, according to growing site). Among three reaction kinetic models, pseudo-second-order kinetics model showed best results. Since sample taken from the most anthropogenic influenced area have almost 30 % lower adsorption capacity than others, it can be concluded that growing site characteristics reflect on biomass performances, which is important factor for any further biomass usage.