The effect of biologically active compounds in the mucus of slugs Limax maximus and Arion rufus on human skin cells

Molluscs are one of the sources of biologically active substances, which are now intensively studied, especially for their anti-cancer properties. Malignant melanoma originates from melanocytes, develops very quickly and is associated with poor prognosis. Therefore, the aim of the study was to assess the properties of biologically active compounds in sterile mucus isolated from slugs Limax maximus and Arion rufus. Tested mucus were isolated using the new self-developed method which is safe for the environment and the animal donors. The impact of the mucus on human keratinocytes CCD 1106 KERTr and malignant melanoma cells A-375 was examined using MTT assay and SRB assay, which allowed us to determine the cell metabolic activity and cell number after treating them with slug mucus isolated from Limax maximus and Arion rufus decreased human keratinocytes and melanoma cells metabolic activity as well as manifested properties of reducing the number of cells in both tested cell lines, and therefore can be a source of biologically active substances with anticancer potential.

Light-insulating apparatus of the camera-like eye of the terrestrial gastropod mollusk Arion rufus (Heterobranchia, Stylommatophora)

The cellular composition, the morphology of the components, and the screening function and evolutionary changes of the light-insulating apparatus of the camera-like eye of the terrestrial gastropod pulmonate mollusk Arion rufus were studied and evaluated using light and electron microscopy. According to all the considered characteristics, the light-insulating apparatus of A. rufus is typical for terrestrial pulmonate mollusks. Evolutionary transformations of the light-insulating apparatus, caused by the change in the mollusks' environment, are insignificant and affect the cellular composition, the morphology of pigmented cells and the isolation of the light-sensitive parts of photoreceptor cells from each other.

Nematodes associated with terrestrial slugs in the Edmonton region of Alberta, Canada

A survey of nematodes associated with terrestrial slugs was conducted in residential gardens, nurseries, greenhouses and agricultural sites located in and around Edmonton, Alberta, Canada. A total of 2406 slugs were collected from 82 sites. Slugs were decapitated and cadavers were incubated for two weeks, with emerging nematodes removed and processed for identification. Nematodes were identified using molecular sequence data for the 18S ribosomal DNA. Nematodes were recovered from 20 of the 82 sites surveyed, with 24.4% of the slugs infected with nematodes. A total of seven nematodes were identified to species level, including Caenorhabditis elegans, Panagrolaimus papillosus, Pellioditis typica, Pelodera pseudoteres, Rhabditella axei, Rhabditoides inermiformis and Phasmarhabditis californica. An additional four specimens were identified to genus level, including Oscheius sp. (9), Pristionchus sp., Rhabditis sp. and Rhabditophanes sp. (1). The two most common nematode species were C. elegans and P. pseudoteres. The facultative parasite, P. californica, was recovered from a single Arion rufus specimen, collected from a seasonal nursery. To our knowledge, this study represents the first survey of slug-associated nematodes in Canada.

Towards the unravelling of the slug <i>A. ater–A. rufus</i> complex (Gastropoda Arionidae): new genetic approaches

The genus Arion includes several slug species, some of which are considered to be a pest to both cultivated and wild flora. Within this genus, the Arion ater complex comprises two different morphological forms: Arion rufus and A. ater, but there is no consensus about their species status. Their phylogenetic relationships have been recently solved, both of them belonging to different phylogenetic clades, but their species status is still unclear (as different clades are not always different species). For this reason, the aim of this study was to precisely identify these species status by employing the up-to-date multi-rate Poisson tree processes (mPTP) methodology as well as the classic methodology of genetic distances, both of which have three different mitochondrial genes. Results confirmed that both A. ater and A. rufus are independent evolutionary clades, and the high genetic distances between them (K2P distances ranged between 9.1 and 16.4 %, depending on genes) together with mPTP analyses, supported the idea that the clades correspond to different species. Results will be useful for the classification of these specific species as well as for developing proper pest control methodologies and conservation policies in both cultivated and wild plants.