Among the plants that exhibit significant or established pharmacological activity, the genus Artemisia L. deserves special attention. This genus comprises over 500 species belonging to the largest Asteraceae family. Our study aimed at providing a comprehensive evaluation of the phytochemical composition of the ethanol extracts of five different Artemisia L. species (collected from the southwest of the Russian Federation) and their antimicrobial and nematocide activity as follows: A. annua cv. Novichok., A. dracunculus cv. Smaragd, A. santonica cv. Citral, A. abrotanum cv. Euxin, and A. scoparia cv. Tavrida. The study of the ethanol extracts of the five different Artemisia L. species using the methods of gas chromatography–mass spectrometry (GC–MS) and high-performance liquid chromatography–quadrupole time-of-flight mass spectrometry (HPLC–MS/MS) allowed establishing their phytochemical profile. The obtained data on the of five different Artemisia L. species ethanol extracts’ phytochemical composition were used to predict the antibacterial and antifungal activity against phytopathogenic microorganisms and nematocidal activity against the free-living soil nematode Caenorhabditis elegans. The major compounds found in the composition of the Artemisia L. ethanol extracts were monoterpenes, sesquiterpenes, flavonoids, flavonoid glycosides, coumarins, and phenolic acids. The antibacterial and antifungal activity of the extracts began to manifest at a concentration of 150 µg/mL. The A. dracunculus cv. Smaragd extract had a selective effect against Gram-positive R. iranicus and B. subtilis bacteria, whereas the A. scoparia cv. Tavrida extract had a selective effect against Gram-negative A. tumefaciens and X. arboricola bacteria and A. solani, R. solani and F. graminearum fungi. The A. annua cv. Novichok, A. dracunculus cv. Smaragd, and A. santonica cv. Citral extracts in the concentration range of 31.3–1000 µg/mL caused the death of nematodes. It was established that A. annua cv. Novichok affects the UNC-63 protein, the molecular target of which is the nicotine receptor of the N-subtype.

Researchers are looking for the most effective ways to extract the bioactive substances of Juniperus communis L. berries, which are capable of displaying the greatest range of biological activity, namely antimicrobial potential “against phytopathogens”, antioxidant activity and nematocidal activity. This study provides detailed information on the chemical activity, group composition and biological activity of the extracts of juniper berries of 1- and 2-year maturity (JB1 and JB2), which were obtained by using different solvents (pentane, chloroform, acetone, methanol and 70% ethanol) under various extraction conditions (maceration and ultrasound-assisted maceration (US)). Seventy percent ethanol and acetone extracts of juniper berries were analyzed via gas chromatography–mass spectrometry, and they contained monoterpenes, sesquiterpenes, polysaccharides, steroids, fatty acid esters and bicyclic monoterpenes. The antimicrobial activity was higher in the berries of 1-year maturity, while the acetone extract obtained via ultrasound-assisted maceration was the most bioactive in relation to the phytopathogens. Depending on the extraction method and the choice of solvent, the antioxidant activity with the use of US decreased by 1.5–1.9 times compared to the extracts obtained via maceration. An analysis of the nematocidal activity showed that the sensitivity to the action of extracts in Caenorhabditis elegans was significantly higher than in Caenorhabditis briggsae, particularly for the acetone extract obtained from the juniper berries of 1-year maturity.

Phytopathogenic nematodes have a negative impact on crop productivity. Currently, the main method of controlling these pests is the use of synthetic nematocides. Despite their high efficacy and ease of use, synthetic nematocides can pose a risk to both agricultural producers and consumers of crop products. An alternative to the use of chemical plant protection products can be the use of substances of natural origin, such as plant extracts. When using plant extracts to control agricultural pests, it should be borne in mind that the biological activity of extracts depends not only on the plant species, but also on the method of obtaining the extract. This work presents data on the physicochemical properties and biological activity of the extracts of Tagetes patula Lemon Drop variety obtained using four extractants of different polarity: ethanol, chloroform, n-hexane and methyl tert-butyl ether. The pH, total carotenoids, phenols, flavonoids and thiophenes content were determined for each extract. The biological activity of the extracts was studied in experiments with the free-living soil nematode Caenorhabditis elegans. All extracts had dose-dependent toxic effects on C. elegans organisms. The toxicity of the extracts depending on the solvent decreased in the series: chloroform > ethanol > n-hexane > methyl tert-butyl ether. The revealed differences in nematocidal activity of the extracts correlated with the content of phenols and carotenoids in them.

Проведено изучение возможной роли рецепторов дофамина DOP-1, DOP-2 и DOP-3 в модуляции чувствительности почвенной нематоды Caenorhabditis elegans к токсическому действию нитрата свинца. Эксперименты проводили с нематодами четырех линий: линия дикого типа N2 и мутантные линии LX636 (dop-1(vs101)X), LX702 (dop-2(vs105)V), LX703 (dop-3(vs106)X) с нуль-мутациями одного из генов рецепторов дофамина (dop-1, dop-2 и dop-3 соответственно). Нуль-мутации генов рецепторов дофамина DOP-2 и DOP-3 не вызывали достоверных изменений устойчивости поведения C. elegans к действию Pb(NO₃)₂ в концентрации 0.25–1.0 мМ. Нуль-мутация гена рецептора DOP-1 повышала чувствительность поведения C. elegans к ионам Pb²⁺ в течение 30–120-минутной экспозиции к токсиканту. Введение в среду инкубации дофамина в концентрации 8 мМ не оказывало существенного влияния на поведение C. elegans, но снижало чувствительность нематод линий с мутациями генов dop-1 и dop-3 к Pb(NO₃)₂. Дофамин в концентрации 4 мМ не оказывал достоверного влияния на локомоцию C. elegans всех четырех линий как сам по себе, так и при добавлении в среду с нитратом свинца. Нарушения моторной программы плавания у dop-1 мутантов могут быть следствием пониженного содержания эндогенного ацетилхолина в моторных нейронах в результате недостаточной DOP-1 дофаминергической трансмиссии. Снижение чувствительности dop-1 и dop-3 мутантов к Pb(NO₃)₂ при введении в среду инкубации 8мМ дофамина свидетельствует о том, что у C. elegans этих линий чувствительность к дофамину сохраняется. Список литературы

A series of hexadecylpiperidinium surfactants containing alkyl (PMe-16, PEt-16, PBu-16), benzyl (Benz-16, 1-Benz-3-HP-16, 1-Benz-4-HP-16), and hydroxyl (3-HPMe-16, 4-HPMe-16) substituents in the ring were tested with the nematode Caenorhabditis elegans to investigate the relationship between nematocidal activity and the structural features of surfactants. It was found that increasing the hydrophobicity of the substituent in the surfactant head group reduced the nematocidal activity in the order PMe-16 > PEt-16 > PBu-16 > Benz-16. The lead compound, PMe-16, showed significantly higher activity than the commercial insecticide carbofuran, and was able to induce nearly complete nematode mortality within 24 h at a concentration of 50 μg·mL⁻¹, as well as suppress culture development at concentrations of 25–100 μg·mL⁻¹. All tested piperidinium surfactants inhibited nematode population development at 100 μg·mL⁻¹, while PMe-16 remained effective at concentrations as low as 25 μg·mL⁻¹. The membranotropic properties of the surfactants were evaluated using a turbidimetric method with dipalmitoylphosphatidylcholine (DPPC)-based liposomes as a model of biomembranes. Dynamic light scattering measurements were performed in parallel to assess changes in liposome size and zeta potential as a function of surfactant content, as well as to determine the critical concentration required to induce lipid bilayer destabilization. These results provide indirect evidence of surfactant–membrane interactions. The combinations of piperidinium surfactants and carbofuran showed pronounced synergistic effects, reducing the insecticide dose while maintaining efficacy. Synergy was evaluated using the Bliss independence model and the Highest Single Agent model. The addition of the most active surfactants (PMe-16 and 4-HPMe-16) at 6.25 μg·mL⁻¹ enabled an approximately twofold reduction in the carbofuran dose while maintaining full nematocidal activity.

Подход «Единое здоровье» как эффективный способ управления экологическими рисками (на примере цианотоксинов)