Vitaly Kazarin

The diplopod genus Leptoiulus Verhoeff, 1894 is new to the fauna of China, due to the discovery of L. hebeiensis sp. nov. from Hebei Province. A description of the new species is provided. The family Julidae Leach, 1814 is represented in China by 5 genera, all keyed, including Leptoiulus. A basic review of the Julidae occurring in China including Taiwan is presented.

The structure of leaf epidermis in species from three sections (Diplolobus, Gymnolobus, and Siphisia) of the genus Aristolochia has been examined by light and scanning microscopy methods. As the results show, the number of the stomata and the length of stomatal guard cells in plants growing ex situ are not related to habitat conditions but are probably determined genetically. According to the type of leaf epicuticular waxes, the studied taxa can be divided into three groups, of which the Aristolochia-type is the most common. This type is characteristic of all studied species of the section Siphisia. The presence of two types of trichomes in members of this section distinguishes them from the other sections. Representatives of the sections with the Convallaria-type wax lack trichomes. The noted differences allow accurate identification of each of the species in the genus. The features of the epidermis surface, types and arrangement of stomata, and types of trichomes are additional diagnostic characteristics useful for taxonomy.

The cultivation of Panax ginseng C.A. Meyer, a valuable medicinal plant, presents a number of challenges due to its physiology and life cycle. The composition of the soil and the microbiome living in it are important for plant growth and root quality. Modern analytical methods were used to identify differences in the rhizosphere soils of plants in the forest and in the plots. Microbiological and molecular genetic methods were used to isolate and identify bacterial isolates from these soils, allowing for the establishment of a working collection of potentially useful bacterial strains. Increases in soil pH in the plots and changes in the amount of macronutrients partially explained the changes in the activity of the forest and plot isolates and the composition of the cultivated strains. The cultivated strains belonged to the rhizosphere-dominant phyla Pseudomonadota, Bacillota, and Actinomycetota of the main functional groups of soil potassium, phosphorus, and nitrogen transformations. The ratio of bacteria functional groups was comparable in the forest and in the plots. The most common phylum of cultured microorganisms was Bacillota, while the main differences were observed in the functional group of potassium-solubilizing bacteria belonging to the phyla Pseudomonadota.

The genus Skleroprotopus Attems, 1901 is represented in China by five species, all keyed and mapped, including Skleroprotopus securifer Mikhaljova sp. nov. Taxonomic and distributional remarks are provided for all of the species.

Background: Recent interest in plant-derived exosome-like nanoparticles (ENs) has surged due to their therapeutic potential, which includes antioxidant, anti-inflammatory, and anticancer activities. These properties are attributed to their cargo of bioactive metabolites and other endogenous molecules. However, the properties of ENs isolated from plant cell cultures remain less explored. Methods: In this investigation, grape callus-derived ENs (GCENs) were isolated using differential ultracentrifugation techniques. Structural analysis through electron microscopy, nanoparticle tracking analysis, and western blotting confirmed that GCENs qualify as exosome-like nanovesicles. Results: These GCENs contained significant amounts of microRNAs and proteins characteristic of plant-derived ENs, as well as trans-δ-viniferin, a notable stilbenoid known for its health-promoting properties. Functional assays revealed that the GCENs reduced the viability of the triple-negative breast cancer cell line MDA-MB-231 in a dose-dependent manner. Moreover, the GCENs exhibited negligible effects on the viability of normal human embryonic kidney (HEK) 293 cells, indicating selective cytotoxicity. Notably, treatment with these GCENs led to cell cycle arrest in the G1 phase and triggered apoptosis in the MDA-MB-231 cell line. Conclusions: Overall, this study underscores the potential of grape callus-derived nanovectors as natural carriers of stilbenoids and proposes their application as a novel and effective approach in the management of cancer.