Marksa, Mindaugas

Background: Artemisia absinthium (L.) is a perennial, aromatic, shrubby plant. This plant belongs to the Asteraceae family [1]. It is found in all regions of Lithuania, growing in abandoned soil, dry slopes, fallow land, landfills, roadsides [2]. Artemisia absinthium L. has been used as a medicinal plant since ancient times. It is one of the most popular plants, characterized by its antimicrobial, hepatoprotective, anti-inflammatory, and cardiovascular disease-preventing effects [3]. Aim: To perform a qualitative and quantitative analysis of essential oils extracted from plant raw materials of Artemisia absinthium L. growing in different regions of Lithuania. Methods: Artemisia absinthium L. plant material was collected in summer season of 2024 and 2025 (during the flowering period). Essential oils were extracted from the collected plant material using water steam distillation (the temperature - 120°C, the duration – 2 hours). Then the qualitative and quantitative analysis of the obtained essential oils was performed using the gas chromatographymass spectrometry method. The data from the tests were processed using “Microsoft Excel 2024”. Results: Qualitative analysis of Artemisia absinthium L. essential oils revealed that the dominant compounds are neryl acetate, lavandulyl propionate, geranyl pentanoate, (-)-terpinen-4-ol, and geranyl isovalerate. The largest number of different substances was identified in a sample of Artemisia absinthium L. essential oil, the raw material for which was collected in Kaišiadorys. The results of the quantitative analysis of Artemisia absinthium L. essential oils showed that the highest amount of essential oil in terms of total peak area was extracted from plant material collected in Labeikiai, Ukmergė district. The results were statistically significant (p<0,05). Conclusion: The largest number of different substances was detected in Artemisia absinthium L. essential oil, whose raw material was collected in Kaišiadorys. And the highest content of essential oil was found in raw material, which was collected in Labeikiai, Ukmergė district.

Background: Pomegranate (Punica granatum L.) fruits are rich in bioactive compounds, including punicalagins and ellagic acid, which have been reported to exhibit antidiabetic, anticancer, antimicrobial, neuroprotective effects [1-5]. Understanding their distribution in peels, seeds, and juice across cultivars is important for practical applications. Aim(s): This study aimed to qualitatively and quantitatively evaluate punicalagins (α and β) and ellagic acid in peels, seeds, juice of pomegranate fruits available on the Lithuanian market. Methods: Punicalagins and ellagic acid were quantified using high-performance liquid chromatography (HPLC) with UV detection. Compounds were identified by retention time and UV spectrum compared with standards; results expressed as mg/g of dry weight. Results: Punicalagins and ellagic acid contents varied by cultivar and tissue type, with punicalagins being highest in peel, followed by seeds and juice. In seeds, punicalagins ranged 0.25 – 2.17 mg/g (α) and 0.48 – 2.98 mg/g (β); lowest amounts detected were in Emek (Spain) (β=0.48 mg/g) and Acco (Spain) (α=0.25 mg/g), while highest were in Wonderful 1 (France) (α=2.17 mg/g; β=2.98 mg/g). Seed ellagic acid ranged 0.07 (Emek, Spain) – 0.19 mg/g (Red Loose, Peru). In juice, punicalagins were barely detectable, while ellagic acid ranged 0.02 (Valenciana, Spain) – 0.16 mg/g (Emek, Spain). Peels contained the highest phenolic concentrations, with punicalagin α ranging 19.03 – 47.42 mg/g and β ranging 24.67 – 57.44 mg/g; lowest amounts detected were in Wonderful 2 (Spain) (α=19.03 mg/g; β=24.67 mg/g) and highest in Wonderful 1 (France) (α=47.42 mg/g; β=57.44 mg/g). Peel ellagic acid ranged 1.46 (Hicaz, Turkey) – 2.75 mg/g (Emek, Spain). Cultivar differences were most notable in peels, while juice contained the lowest levels. Conclusion: Bioactive compound accumulation varies by cultivar and tissue, with peels showing the highest total punicalagins and ellagic acid. Seeds contained lower amounts, while juice contributed only minor amounts. These differences should be considered when selecting pomegranate as raw material.

Background: Phytochemicals presented in most plants have proven to have notable medicinal properties, including flavones such as luteolin and apigenin. Studies indicate that these phytochemicals have potential neuroprotective and cardioprotective properties [1-2]. In addition, alternative solid pharmaceutical forms like microcapsules and lyophilized powder provide effective drug content entrapment and dissolution performance [3]. Aim: To compare the encapsulation of the flavones apigenin and luteolin in microcapsules and lyophilized powder. Methods: Apigenin and luteolin were obtained from Artemisia annua L. ethanolic extract, prepared with ultrasonication and L-glutathione as the extraction excipient. The plant extract was dealcoholized, combined with maltodextrin (1:1, w/w) and freeze-dried at -80 oC for 3 days. Separately, the double emulsion (W/O/W) containing the same plant extract, cannabis oil and sodium alginate was used to produce microcapsules via coacervation method with calcium chloride as the crosslink solution. Lyophilized powder and the microcapsules were dissolved in a phosphatic buffer (pH 6.8) and the samples were analyzed with High-Performance Liquid Chromatography (HPLC). Results: Apigenin and luteolin were identified by UV detection at 340 nm and 350 nm, respectfully. The lyophilized powder showed the phytochemical content to be 85,0 ± 4,3 % of apigenin and 86,0 ± 4,3 % of luteolin. The microcapsules revealed to have an increased encapsulation efficiency of 88.13 ± 3.13% for apigenin and 88.41 ± 4.17% for luteolin. The minor differences of the drug entrapment efficiency may be attributable to processing factors, including the preparation temperature and the particle size. Conclusion: Microcapsules achieved a slightly higher flavonoid encapsulation efficiency than lyophilized powder under the conditions evaluated. These results provide a basis for further research.

Background: Walnut septa, traditionally discarded as waste in walnut processing because they primarily serve a structural function in the walnut fruit, have recently gained attention for their potential abundance of phenolic compounds, suggesting their overlooked value (1). Aim: This study aimed to investigate the influence of regional variations on the antioxidant activity and phenolic composition of Juglans regia L. septa. Methods: Walnuts (Juglans regia L.) septa were collected from various regions of Lithuania (Šiauliai, Šakiai district, Širvintos, Utena, Marijampolė, Lazdijai, Kaunas, Veliuona, Gargždai, Biržai, Anykščiai district and Alytus), also Armenia and Ukraine. Determination of phenolic compounds was done using Folin-Ciocalteu reagent and spectrophotometry. Antioxidant activity by CUPRAC assay was measured spectrophotometrically, qualitative analytical profile was determined by performing HPLC analysis in combination with mass spectrometry (MS). Results: Samples from 12 different regions in Lithuania, Armenia, and Ukraine were analysed. The total phenolic content ranged from 131.55 to 530.92 mg GAE/g dw. Among all the regions studied, the Šiauliai sample demonstrated the highest concentrations of phenolic compounds (530.92 ± 2.03 mg GAE/g), and antioxidant activity (1503.26 ± 4.61 μmol TE/g dw), with statistically significant differences compared to the other samples (p < 0.05). An LC-MS-PDA analysis of J. regia septa extract samples was performed. Nine phenolic compounds were identified, including ellagic acid, quercitrin, and caffeoyl derivatives, which are widely recognized for their antioxidant and antiinflammatory properties. Conclusion: Geographical origin was found to significantly influence the phytochemical composition and antioxidant capacity of walnut septa. These results indicate a strong relationship between environmental conditions—such as cooler temperatures—and secondary metabolite accumulation. The chemical profiling via LC-MS confirmed the presence of several key phenolics, indicating that walnut septa are a rich and diverse source of bioactive compounds.

Background: For assessing antioxidant activity of hydrophilic and lipophilic compounds, hydrophilic standards (Trolox, ascorbic acid, gallic acid, rutin, etc.) are most commonly used in spectrophotometric studies. However, for lipophilic substances, it is more appropriate to perform the analysis in non-aqueous conditions and compare their activity with a lipophilic standard. α‑Tocopherol serves as such a standard, demonstrating activity comparable to Trolox (1). Therefore, a DPPH-based method in a non-aqueous medium was developed using α‑tocopherol as a standard and applied to chamomile essential oil. Aim(s): To develop and apply a non-aqueous DPPH spectrophotometric method for the assessment of antiradical activity of lipophilic compounds using tocopherol acetate as a lipophilic reference standard, and to express the activity of chamomile essential oil in tocopherol equivalents. Methods: Tocopherol acetate was dissolved in methanol and diluted (1000–62.5 µg/mL). DPPH (0.003 g/100 mL) in acetonitrile was mixed with 50 µL of tocopherol solution in 5.0 mL and incubated 20 min. Absorbance at 517 nm was measured in triplicate; calibration curve: y = 0.0005x + 0.0141 (R² = 0.9994). Chamomile oil (400 µL in 5 mL methanol) was analyzed similarly; absorbance converted to tocopherol equivalents. Results: A linear calibration curve for tocopherol acetate in 62.5–1000 µg/mL was obtained, demonstrating excellent linearity (R² = 0.9994). The antiradical activity of chamomile essential oil under non-aqueous conditions corresponded to 67.8 µg/mL tocopherol acetate, equivalent to ~3.39 µg per reaction mixture (50 µL added). The analyzed oil in the mixture was ~3.70 µL (50 µL of 7.41% v/v solution). Conclusion: A non-aqueous DPPH method suitable for lipophilic compounds was developed using tocopherol acetate. This enables expressing essential oil activity in tocopherol equivalents, more appropriate than hydrophilic standards in non-aqueous systems. Further studies will integrate HPTLC and GC to determine contributions of individual components.

Background: Ruta graveolens L. has a wide range of ethnopharmacological applications that are confirmed and further explored by modern evidence-based research. In the western regions of Ukraine, the plant has traditionally been used as an anti-inflammatory agent, including herbal baths for the treatment of skin diseases in infants [1]. In Lithuanian local medicine, its use has been documented for the treatment of abdominal pain, nervous and cardiovascular disorders, as well as as an abortifacient [2]. Based on these traditional applications, modern studies investigate the anticancer, neuroprotective, and antimicrobial potential of rue. Aim: To evaluate the content of phenolic compounds in rue as one of the key groups of biologically active compounds potentially responsible for the plant’s therapeutic properties. Methods: The aerial parts of Ruta graveolens were collected at the I. Franko Botanical Garden in 2023. The quantitative determination of total phenolic compounds was performed in methanolic extracts using spectrophotometry on a Halo DB-20 UV–Vis spectrophotometer at 760 nm, employing the Folin–Ciocalteu reagent [3]. Results: The content of phenolic compounds showed a clear dependence on the vegetation phase. A moderately high level was observed during mass budding and the beginning of flowering. The maximum accumulation occurred during mass flowering, with levels approximately 1.2 times higher than in the budding phase, indicating intensified biosynthesis during the active reproductive development stage. During mass fruiting, the content decreased by more than twofold, followed by a secondary increase after fruiting to values comparable to the maximum. Conclusions: The results demonstrate a phenological pattern of phenolic compound accumulation in Ruta graveolens. Considering the established role of phenolic compounds in anti-inflammatory and potential antitumor activities, the mass flowering stage is identified as the optimal phase for harvesting plant material rich in biologically active compounds.

Background: The most commonly used raw material of Japanese quince is the fruit, which is characterized by a high content of ascorbic acid, catechin, epicatechin, quercetin, and chlorogenic acid [1]. However, research indicates that the leaves contain diversified phenolics comphounds (33- 36 compounds) among which chlorogenic acid turned out to be the main constituents [2]. Aim: The aim of study was to determine and compare the quantitative variation of chlorogenic acid in the leaves of Chaenomeles japonica during vegetation stages. Methods: The raw material was collected in the Alytus district during the vegetation period from April to October. 1 g of crushed raw material was extracted with 10 mL of 70% methanol. The prepared samples were placed in an ultrasonic bath for 30 minutes and later were centrifuged for 6 minutes at 4700 rpm and filtered through membrane filters. Analysis was performed by high performance liquid chromatography. Results: The highest content of chlorogenic acid (4703.37 µg/g) in the quince leaf samples was found at the end of May. High level was also set at the beginning of June (4475.7 µg/g). A significant decrease was observed during the main flowering period at the end of June (1300.95 µg/g). Meanwhile, the lowest level (740.08 µg/g) was measured in October samples. Conclusion: To get the highest amount of chlorogenic acid it is advisable to collect quince leaves at the beginning of vegetation in May.

Background/Objectives: The development of novel small-molecule kinase inhibitors remains an important strategy in anticancer drug discovery. Receptor tyrosine kinases such as c-MET and HER2 are clinically relevant targets involved in tumor progression and resistance mechanisms. The aim of this study was to design, synthesize, and biologically evaluate a series of 3-[(2,4-difluorophenyl)amino]propanoic acid derivatives as potential antiproliferative agents and to explore their possible interactions with selected kinase targets. Methods: A series of ester, hydrazide, hydrazone, semicarbazide, triazolone, and triazolethione derivatives (2–21) were synthesized and structurally characterized by NMR, IR spectroscopy, and microanalysis. The compounds were evaluated for in vitro anticancer activity against A549 and Caco-2 human cancer cell lines. In addition, molecular docking studies were performed to investigate binding interactions with c-MET and HER2 receptor tyrosine kinases. Cytotoxicity toward non-transformed HEK293 cells was also assessed. Results: The synthesized derivatives demonstrated structure–activity relationships, with compounds 6b, 7f, 7g, and 9 exhibiting the most pronounced antiproliferative effects, reducing cancer cell viability by approximately 50% in both tested cell lines. Molecular docking indicated that compound 9 displayed favorable predicted binding energies toward c-MET and HER2, forming hydrophobic and hydrogen-bond interactions within the active sites and showing overlapping contacts with native ligands and reference inhibitors. Active compounds also demonstrated cytotoxic effects in HEK293 cells comparable to those of doxorubicin and cisplatin. Conclusions: These results identify 3-[(2,4-difluorophenyl)amino]propanoic acid derivatives, particularly compound 9, as promising scaffolds for further structural optimization toward the development of kinase-targeting antiproliferative agents.

Continuing our work in the field of synthesis and research of amino acids, their derivatives, and cyclization products, in this work, we synthesized various 3-(6-bromo-2-oxo-1,3-benzoxazol-3(2H)-yl)propanoic acid derivatives and investigated their antimicrobial activity. A total of eighteen synthesized chemical compounds (No. 1–18), including several structural analogues (e.g., 3a, 3b, 4a–4e, 8a–8m, 9a–9d), were evaluated for their antibacterial properties. The antibacterial activity was assessed using the Kirby–Bauer disk diffusion method, and inhibition zone diameters (mm) were measured against five representative bacterial strains: S. aureus, MRSA, B. subtilis, E. coli, and P. aeruginosa. The minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of the most active synthesized compounds were determined against representative Gram-positive and Gram-negative bacterial strains, including S. aureus, MRSA, B. subtilis, and E. coli. Overall, these results indicate that the tested compounds display selective antibacterial activity, mainly against Gram-positive bacteria, with compound 12 emerging as the most promising derivative in the series. The antibacterial activities of several synthesized compounds were systematically evaluated against S. aureus and MRSA over a 24 h incubation period, with optical density measured at ten time points. Bacterial growth was monitored spectrophotometrically at 600 nm (OD600) at 1, 2, 3, 4, 5, 6, 7, 8, 20, and 24 h, enabling a detailed assessment of growth kinetics and the temporal dynamics of inhibition. The effect of compound 11 on the growth kinetics of S. aureus was evaluated by quantifying viable bacterial counts (log10 CFU/mL) over a 6 h incubation period, and the results are presented in the time–kill curve. Compound 11 was selected for this experiment because it exhibited the most pronounced antibacterial activity against S. aureus in the disk diffusion assay. The cytotoxicity of compounds 9a, 11, 12, and 13 was evaluated at concentrations ranging from 125 to 1.95 µg/mL. The results showed a clear, concentration-dependent decrease in cytotoxicity for all tested compounds. The molecular structure of compound 3a was confirmed by a single-crystal X-ray diffraction.

Įžanga. Augalai yra gausus aminorūgščių šaltinis, o žmogaus organizmas daugiau nei 60% reikalingų baltymų gauna būtent iš augalinių produktų [1]. Nepakeičiamos aminorūgštys nėra sintetinamos žmogaus organizme, todėl jas svarbu gauti su maistu. Aminorūgštys atlieka svarbų vaidmenį žmogaus organizme. Jos dalyvauja daugelyje organizme vykstančių procesų, yra svarbios baltymų, hormonų ir neuromediatorių sintezėje [2]. Taip pat aminorūgštys yra būtinos maistinių medžiagų, tokių kaip angliavandeniai, baltymai, riebalai, vitaminai, mineralai, transportavimui ir saugojimui [1]. Tikslas. Nustatyti ir palyginti nepakeičiamųjų aminorūgščių kiekius rūgtinių (Polygonaceae L.) šeimos augaluose (valgomosios rūgštynės (Rumex acetosa L.), daržoviniai rabarbarai (Rheum rhabarbarum L.)) skirtingu vegetacijos laikotarpiu. Metodai. Aminorūgščių kokybinis ir kiekybinis nustatymas buvo atliktas, naudojant dujų chromatografijos - masių spektrometrijos su junginių derivatizacija metodą. Žaliavų ėminiai buvo rinkti 2025 metais balandžio - rugsėjo mėnesiais, Kėdainių rajone. Tyrimai buvo kartojami tris kartus. Rezultatai. Atlikus kiekybinę analizę džiovintuose valgomųjų rūgštynių (Rumex acetosa L.) lapų, daržovinių rabarbarų (Rheum rhabarbarum L.) stiebų mėginiuose gauti rezultatai rodo, kad statistiškai reikšmingai didesnį kiekį nepakeičiamųjų aminorūgščių kaupia valgomųjų rūgštynių lapai, lyginant su daržovinių rabarbarų stiebais. Didžiausias bendras aminorūgščių kiekis valgomosiose rūgštynėse buvo nustatytas vegetacijos pabaigoje rugsėjo mėnesį (21,34 ± 1,683 µg/g), o mažiausias - intensyvaus augimo metu balandžio (3,00 ± 0,156 µg/g) ir gegužės (1,28 ± 0,116 µg/g) mėnesiais. Daržoviniuose rabarbaruose didžiausias bendras aminorūgščių kiekis buvo nustatytas žydėjimo metu liepos mėnesį (2,36 ± 0,229 µg/g), o mažiausias - intensyvaus augimo metu balandžio (0,04 ± 0,003 µg/g) ir gegužės (0,05 ± 0,004 µg/g) mėnesiais. Išvados. Atlikus nepakeičiamųjų aminorūgščių kokybinį ir kiekybinį nustatymą dujų chromatografijos - masių spektrometrijos su junginių derivatizacija metodu, buvo identifikuotos šios aminorūgštys: L-valinas, L-leucinas, izoleucinas, L-treoninas, L-fenilalaninas. Valgomųjų rūgštynių lapų ėminiai pasižymėjo statistiškai reikšmingai didesniu nepakeičiamųjų aminorūgščių kiekiu lyginant su daržovinių rabarbarų stiebų ėminiais.