Repozitoriul Instituțional al Universității de Stat din Moldova (RI USM)

Institutional Repository of Moldova State University (IR MSU)

Repozitoriul Instituțional al Universității de Stat din Moldova reprezintă arhiva digitală cu acces deschis a rezultatelor cercetărilor științifice și științifico-didactice efectuate în cadrul universității. Conținutul arhivei este multidisciplinar și include lucrări din domeniile științelor exacte și socio-umanistice.
The Institutional Repository of the State University of Moldova is an open access digital archive of the results of scientific and scientific-didactic research carried out within the university. The archive's content is multidisciplinary and includes works from the fields of exact sciences, social sciences and humanities.

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Recent Submissions

Employment of in silico in prediction of furan derivatives as efficient corrosion inhibitors for mild steel in acidic media [Articol]
(2025) Qasim, Maimoonah Khalid; Khalil, Rabah Ali
This study highlights the role of computational approaches in advancing the design of corrosion inhibitors by virtually screening novel candidate molecules. In silico treatment based on quantitative structure-activity relationship (QSAR) analysis was performed on already published experimental results of corrosion inhibition efficiency (IE%) of mild steel in acidic media for eighteen furan derivatives. The theoretical treatments are based on density functional theory (DFT) at B3LYP level. It was found that the global minimum of the furan derivatives can be reached at a medium basis set of 6–21G. A sophisticated model consisting of four descriptors excluding the sulphur correction term with physical meaning and good statistical criteria of squared correlation coefficient (r2) and standard error (SE) equal to 0.914 and 5.029, respectively, is presented. The suggested model can be considered as a powerful tool for understanding the role of chemical composition in preventing corrosion which helps researchers in the development process. The in silico treatment was utilized for suggesting twelve furan derivatives with an extremely high IE% which might be used as excellent materials for corrosion inhibition when synthesized and applied experimentally.
Influence of aromatic substituents on the synthesis of schiff bases derived from trans-(R,R)-diaminocyclohexane: a spectrophotometric and dft b3lyp study [Articol]
(2025) Becerra, Lili Dahiana; Coy-Barrera, Carlos; Quiroga, Diego
In this work, the synthesis of Schiff bases derived from trans-(R,R)-diaminocyclohexane by microwave irradiation (MW) is presented. The reaction yields varied between 31% and 69%, being influenced by the electronic nature of the substituents (H, Cl, Br, NO2, MeO, t-BuO, BnO, and 4-(4-Me)PhO) and the reaction temperature. The spectrophotometric properties of the products were investigated by UV-Vis spectrophotometry, revealing bathochromic and hypsochromic effects attributable to the different substituent groups. These effects were interpreted by DFT calculations with the B3LYP functional using the 6–311G(d,p) basis set. The results suggest that the electronic properties of the substituents in the para position have a significant impact on the spectroscopic characteristics of the Schiff bases. The synthesized Schiff bases exhibit great potential for applications in areas such as optical sensors and functional materials, as the substituents can precisely modulate their spectrophotometric properties. This opens up new opportunities for designing compounds with tunable properties for various technological and scientific applications.
Phytochemical analysis and bioactivities of different organs of Bunium ferulaceum Sm [Articol]
(2025) Khaldi, Achraf; Berrezig, Abdelkader Elhadj; Mazeri, Amina; Mehdi, Kheira; Gouabi, Rahima Hadjer
This study provides an integrated chemical and biological evaluation of hydro-methanolic extracts from the leaves, flowering heads, and tubers of Bunium ferulaceum Sm. Phytochemical profiling revealed organ-dependent variations, with leaves rich in phenolics (53.13 mg GAE/g), flavonoids (21.45 mg QE/g), and tannins (10.17 mg TAE/g), while tubers showed the highest triterpene content (8.15 μg UAE/mg). These compositional differences in functional phytochemical classes were statistically correlated with biological responses: triterpenes showed a strong association with anti-inflammatory effects (r= –0.97), while polyphenols, particularly phenolics and flavonoids, were correlated with antibacterial activity (r= –0.91 and –0.90, respectively). The chemical data highlight the coexistence and complementary mechanisms of polyphenols and triterpenoids, supporting a structure-activity relationship that underlies the pharmacological potential of B. ferulaceum. Overall, the study emphasizes the chemical rationale behind its bioactivity, providing a solid basis for future isolation and mechanistic studies.
Spectrochemical characterization of lipid fraction in sunflower pollen [Articol]
(2025) Duca, Maria; Ciocarlan, Alexandru; Mutu, Ana; Clapco, Steliana
Sunflower (Helianthus annuus L.) pollen is a chemically rich but underexplored matrix containing bioactive lipids with nutraceutical and pharmaceutical relevance. Lipid fractions were isolated from hand-collected pollen samples across three distinct agroclimatic zones in Moldova via mini-Soxhlet extraction. Subsequent alkaline saponification and acid methylation enabled GC-MS characterization of fatty acid methyl esters (FAMEs) and unsaponifiable constituents. The mean lipid yield (9.23% w/w) exhibited regional variability, with the highest value in the sample from Visoca (9.90%), likely due to climatic modulation of lipid biosynthesis. Chromatographic profiling resolved >40 constituents, including: Polyunsaturated fatty acid esters (e.g., methyl linolenate, a ω-3 precursor); diterpenoid derivatives (methyl labdatrien-19-oate); oxygenated sterols (lanostan-3-one); lipophilic vitamins (α-tocopherol, retinol derivatives). Chemometric analysis revealed stress-induced shifts in metabolite distribution, with heat/water deficits favouring terpenoid accumulation. The lipidome’s structural diversity-spanning hydrocarbons, esters, and ketones-suggests multifunctional bioactivity (antioxidant, anti-inflammatory). These findings position sunflower pollen as a sustainable source of phytochemical precursors for functional ingredients. Further studies should address structure-activity relationships, stabilization strategies, and green extraction optimization.
Chemical composition and biological evaluation of traditional algerian plants Melissa officinalis L. and Urtica dioica L. [Articol]
(2025) Meridja, Dahia; Belhamel, Kamel; Harrat, Mohamed; Belhamel, Chiraz; Yousfi, Mohamed
Melissa officinalis L. and Urtica dioica L. were investigated for their phytochemical profiles as well as their antioxidant and anti-lithiatic properties. LC-MS/MS analysis revealed that M. officinalis possessed a more complex and diverse composition, particularly rich in flavonoids (myricetin, and quercetin derivatives) and phenolic acids (caffeic, oleanolic, and salicylic), especially in its ethyl acetate fraction, indicating their lipophilic nature. In contrast, U. dioica exhibited a simpler chemical profile, with significant amounts of myricetin, riboflavin, sinapic acid, catechin, and β-carotene in its aqueous fraction. These compositional differences correspond to distinct biological activities. Antioxidant assays (DPPH, ABTS, FRAP) indicated that the ethyl acetate fraction of M. officinalis exhibited the highest radical-scavenging activity. Furthermore, its aqueous extract showed significant anti-lithiatic efficacy, inhibiting calcium oxalate crystal formation by 87.12% at a concentration of 2 mg/mL.