formazans and Hemolysis

Fifty-four strains of lactic acid bacteria obtained from fermented dairy milks were investigated for possible use as probiotics and for colon cancer biological products. Five of these strains inhibited growth of eight food-borne pathogens including Helicobacter pylori, Escherichia coli, and Salmonella typhimurium. Three of these strains survived at pH 2.5 and in 0.3% bile salts. Additionally they produced no haemolysis, were resistant to kanamycin and adhered to Caco-2 cells. 16S rRNA gene sequences of probiotic strains indicated that RM11 and RM28 were Enterococcus faecium and Lactobacillus fermentum, respectively. Both the cultured medium and live whole cells from probiotic strains were tested for antiproliferation of colon cancer cells through MTT and Trypan Blue exclusion assays. The probiotic strains of E. faecium RM11 and L. fermentum RM28 also triggered antiproliferation of colon cancer cells at the rates of 21-29%, and 22-29%, respectively. This suggested that both strains could be used as potential probiotics in functional food or for colon cancer biological products.

Topics: Animals; Bile Acids and Salts; Caco-2 Cells; Cell Survival; Colonic Neoplasms; DNA, Bacterial; DNA, Ribosomal; Enterococcus faecium; Escherichia coli; Formazans; Growth Inhibitors; Helicobacter pylori; Hemolysis; Humans; Hydrogen-Ion Concentration; Limosilactobacillus fermentum; Milk; Probiotics; RNA, Ribosomal, 16S; Salmonella typhimurium; Tetrazolium Salts; Trypan Blue

Marine sponges belonging to the order Haplosclerida are one of the more prolific sources of new natural products possessing various biological activities. The present study examined the cytotoxic and genotoxic potential of ingenamine G, an alkaloid isolated from the Brazilian marine sponge Pachychalina alcaloidifera. Ingenamine G displayed a moderate cytotoxic activity against human proliferating lymphocytes evaluated by the MTT assay (IC(50) 15 microg/mL). The hemolytic assay showed that ingenamine G cytotoxic activity was not related to membrane disruption. The comet assay and chromosome aberration analysis were applied to determine the genotoxic and clastogenic potential of ingenamine G, respectively. Cultured human lymphocytes were treated with 5, 10, 15 and 20 microg/mL of ingenamine G during the G(1), G(1)/S, S (pulses of 1 and 6 h), and G(2) phases of the cell cycle. All tested concentrations were cytotoxic, reduced significantly the mitotic index, and were clastogenic in all phases of the cell cycle, especially in S phase. While an increase in DNA-strand breaks was observed starting with the concentration corresponding to the IC(50). The presence of genotoxicity and polyploidy during interphase and mitosis, respectively, suggests that ingenamine G at high concentrations is clastogenic and indirectly affects the construction of mitotic fuse.

Topics: Adolescent; Adult; Alkaloids; Animals; Apoptosis; Cell Cycle; Cell Proliferation; Cell Survival; Chromosome Aberrations; Comet Assay; DNA Damage; Dose-Response Relationship, Drug; Erythrocytes; Female; Formazans; Hemolysis; Heterocyclic Compounds, 4 or More Rings; Humans; Lymphocytes; Male; Mice; Mutagens; Necrosis; Porifera; Tetrazolium Salts