We investigated the haemolytic capacity of the crude venom extracted from isolated nematocysts of Pelagia noctiluca (Cnidaria: Scyphozoa), and evidenced the proteic fractions responsible for this activity. The nematocyst venom was used at various concentrations to evaluate the haemolytic activity and the lysosomal membrane stability of red blood cells of two teleostean species treated with the extract. The nematocyst extract was assayed against erythrocytes of the two teleostean species living in different environments, Carassius auratus as a common freshwater species, and Liza aurata as a representative of seawater species. Experiments on the haemolytic activity of P. noctiluca in the presence of lipid components of erythrocyte membranes showed that sphyngomyelin strongly inhibited this activity. The crude venom was analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis SDS-PAGE and high performance liquid chromatography (HPLC) to detect the proteic composition, and it was found that the active haemolytic components of this venom are distributed in at least four protein fractions. The results of our experiments indicated that Pelagia noctiluca venom induces haemolysis and lysosomal membrane destabilisation in both species and that Carassius auratus was more susceptible to jellyfish venom than was Liza aurata. No significant differences in glutathione (GSH) levels were observed between control and treatments; consequently the toxins do not cause the oxidative stress but likely recognize specific targets (i.e. sphyngomyelin) in the plasmatic membrane of red blood cells.

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Abstracts:Aquatic animals are continuously exposed to chemical pollutants but the effects evoked in mucins and the carbohydrate nature of the glycoproteins in the unicellular glands in fish epidermis skin surfaces, which receive the most direct contact with them, has not been fully studied and characterized. Moreover, microorganisms use lectins to recognize and bind to host terminal carbohydrates to facilitate the infection whilst host lectins bind to pathogen carbohydrates to exert protective effector functions, such as agglutination, immobilization, and complement-mediated opsonization and killing of potential pathogens. Thus, terminal carbohydrate composition and the presence of a fucose binding lectin (FBL) were determined by lectin ELISA and western blot, respectively, in skin mucus of gilthead seabream (Sparus aurata L.) specimens exposed to waterborne sublethal dosages of heavy metals [arsenic (As2O3), cadmium (CdCl2) and mercury (CH3HgCl) at 5, 5 and 0.04 μM, respectively] after 2, 10 and 30 days. Results showed little effects of heavy metals in the presence of several terminal carbohydrates with few increments or decrements depending on the sugars, exposure time and heavy metal studied. Moreover, the FBL was undetected in any of the control fish skin mucus but was evident in all the heavy metal exposed fish. Further studies are needed to understand the relation of terminal carbohydrates and lectins in skin mucus fish defense and the implications during contamination exposure.Acknowledgements.

In recent decades research in the conservation and restoration field has provided sustainable alternatives to traditional procedures for cleaning or controlling the microbial colonization of works of art. In the present study, for the first time novel bioactive molecules extracted from marine invertebrate organisms (Anthozoa) were tested instead of chemical compounds for removing protein layers or as a biocide for controlling fungal or bacterial colonization. In particular, Bioactive Molecules with Protease activity (BMP), acting in a temperature range of 4-30°C, were tested for the hydrolysis of protein layers on laboratory specimens. The cleaning protocol provides a selective procedure to avoid damage to the original materials constituting the heritage object. Concurrently, enzymatic cleaning was also performed using commercial Protease from Aspergillus sojae (Type XIX), in order to compare their hydrolytic activities. Bioactive Molecules with Antimicrobial activity (BMA 1 , BMA 2 ) were tested to control bacterial (Bacillus, Micrococcus) or fungal (Aspergillus, Penicillium) growth, previously isolated from colonized canvas samples and characterized by an integrated approach based on in vitro culture, microscopy and molecular investigations. These molecules were tested to define the Minimal Inhibitory Concentration (MIC) and Minimal Bactericidal/ Fungicidal Concentration (MBC/MFC). Specifically, BMAs were used to control fungal growth during the relining of the painting (laboratory specimens), carried out using a canvas support, and glue paste as binder. In our hypothesis, these molecules provide an important contribution to the development of innovative protocols for biocleaning or microbial growth control, based on fast and easy application, operator friendly and environmentally sustainable molecules.

Giarratana F., Muscolino D., Beninati Ch., Ziino G., Giuffrida A., Trapani M., Panebianco A . (2014): Gymnorhynchus gigas in Lepidopus caudatus (Actinopterygii: Perciformes: Trichiuridae): prevalence and related effects on fish quality. Czech J. Food Sci., 32: 320-325.We evaluated the effects of Gymnorhynchus gigas on the freshness and hygienic quality of Lepidopus caudatus. Total Volatile Basic Nitrogen (TVB-N), Trimethylamine Nitrogen (TMA-N), as well as Specific Spoilage Organisms (SSOs) are the most important freshness indicators in fish. Our study was carried-out on 65 specimens of L. caudatus kept in ice and stored at 2°C for different period of time. The microbiological charge of SSOs recovered on a portion of parasitised muscles (MP) was compared with those recovered on portions of parasite-free muscles (M). The contents of TVB-N and TMA-N on MP, M, and G. gigas larva/ae were measured using the Conway microdiffusion method. High prevalence (72.31%) of G. gigas in the specimens of L. caudatus from the Mediterranean sea was observed. No statistically significant differences (p < 0.05) between M and MP were found during storage. However, massive infestation of G. gigas on the muscle of the silver scabbardfish could negatively influence TVB-N values, without compromising the sensorial characteristic of fish.

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