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Background Colorectal cancer is the third most commonly diagnosed cancer. Natural compounds, administered together with conventional chemotherapeutic agent(s) and/or radiotherapy, may be a novel element in the combination therapy of this cancer. Considering the anticancer properties of compounds derived from different tissues of various snail species confirmed earlier, the purpose of the present research was to evaluate the effect of extracts from eggs of Helix aspera maxima and Helix aspersa aspersa snails, and fractions of extracts containing particles of different molecular weights on Caco-2 human epithelial colorectal adenocarcinoma cells. Methods The extracts and fractions were analyzed for antioxidant activity, phenols and total carbohydrates using colorimetric methods. Lipid peroxidation products and glutathione in eggs were also examined using these methods. Crude protein and fat in eggs were determined. Molecular weights of egg proteins and glycoproteins were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Astaxanthin, selected vitamins and amino acids in eggs were measured using liquid chromatography methods, and minerals by emission spectroscopy, mass spectrometry or X-ray fluorescence. The action of extracts on the cell viability was determined by the MTT (methylthiazolyldiphenyl-tetrazolium bromide) test, based on the mitochondrial oxidative activity, after 24 and 72 h of treatment. The influence of fractions on the cell viability was assayed after 24 h. The effect of extracts on the percentage of live and dead cells was evaluated by the trypan blue assay, in which live cells exclude trypan blue, while dead cells take up this dye, after 12, 24, 48 and 72 h of treatment. Their influence on the integrity of cell membranes was determined based on the activity of LDH (lactate dehydrogenase), released from damaged cells, after 24 and 72 h of treatment. Then, the effect of extracts on the content of lipid peroxidation products in cells was examined using colorimetric method, after 24 h of treatment. Their influence on types of cell death was determined by flow cytometry, after this time. Results The extracts and their fractions containing molecules

The aim of this research was to evaluate the effect of Ag nanoparticles (nano-Ag) used in the paint covering feed tables or a multimicrobial preparation applied to feed tables on the microbiological composition of the feed table environment, the growth and mortality of snails, and selected parameters for assessing the quality of carcasses and snail shells. The research was carried out in a farm of Cornu aspersum (Müller) snails. In the control (K) group, paint without nano-Ag was used. In two other groups (N-Ag and N-Ag + effective microorganisms (EM)), the feed tables were covered with the same paint as in the control group but with the addition of 100 mg/L of nano-Ag it (N-Ag group). Additionally, multimicrobial preparation (EM Bokashi®) at a concentration of 10% was spread on the tables in the N-Ag + EM group. In the last group (EM), the feed tables were covered with paint without nano-Ag, and only multimicrobial preparation was applied at a concentration of 10%. During the tests, the body weight of snails was measured three times, and swab samples were taken from the feed tables for the examination of microbiological composition. At the end of the experiment, the snails were killed, and the weight of the carcass and the size of the shell were measured. The content of Ag and the degree of lipid oxidation (thiobarbituric acid reactive substances (TBARS)) in the carcasses were analyzed, and the content of Ca and the crushing strength of the shells were determined. In the N-Ag and N-Ag + EM groups, a significant reduction in the total number of bacteria, fecal streptococci, and Escherichia coli was found, while there was also a reduction in mold and fungi in the N-Ag + EM and EM groups. In the K and EM groups, the mortality of animals was higher than in the nano-Ag groups. In subsequent weight checks, the highest body weight was found in the EM group and the lowest in the N-Ag and N-Ag + EM groups. In addition, the carcass weight and shell size in the N-Ag group was significantly lower compared to the K and EM groups. In the N-Ag and N-Ag + EM groups, a higher Ag content in the carcasses and a greater degree of lipid peroxidation were found. The Ca content of the shells was the highest in the N-Ag group, and the hardness of shells was the highest in the N-Ag and N-Ag + EM groups.