Papers by Keyword: Colony Formation

Abstract: Phlogacanthus pulcherrimus T. Anderson (PPT) is an edible plant found in the northern and northeastern regions of Thailand. There is limited information about the anti-breast cancer activity of the ethanolic leaf extract of PPT. This study aimed to evaluate the effects of an ethanolic leaf extract of PPT on MCF-7 breast cancer cell lines. The biological effects, including cytotoxicity, cell apoptosis, colony formation, reactive oxygen species (ROS) formation and cell migration, were determined by a means of sulforhodamine B (SRB), acridine orange/ethidium bromide (AO/EB) staining, a clonogenic assay, flow cytometry and a scratch wound healing assay, respectively. The results demonstrated that the PPT extract showed cytotoxic on MCF-7 cells in a dose-dependent manner with 50% inhibitory concentration (IC₅₀) values of 119.9 ± 12.1 and 51.3 ± 4.7 μg/mL at 24 h and 48 h incubation, respectively. In addition, the extract exhibited cell apoptosis in a dose-dependent manner when used at a concentration of 50–100 μg/mL and inhibited colony formation with an IC₅₀ value of 26.0 ± 2.0 μg/mL when compared with the control group. The extract induced ROS formation in a dose-dependent manner when used at a concentration of 50–100 μg/mL. The extract suppressed MCF-7 cell migration, with significant effect at 25 μg/mL. These results indicate that PPT ethanolic leaf extract has an anticancer activity against MCF-7 breast cancer cells and may be useful for prevention and treatment of breast cancer.

Abstract: The effects of low and high turbulence on the polysaccharides content and colony formation of Microcystis under different nutrition conditions were studied through a laboratory experiment. The rotation speed of 60rpm and 200rpm was provided to represent the turbulence induced by the wind with a speed of 4.0m/s and 6.5m/s in a shallow lake. Transitory and intermittent high turbulence could stimulate the growth of Microcystis and increase of pH value, but the increase of the pH value was not along with the increase of IC. Under eutrophication, N-limited and P-limited conditions, the salvation ratio increased noticeably (increased from 30% to 60%) because of the increase in rotation speed. High turbulence also makes the colony size be smaller than that with low turbulence. Our results suggested that high turbulence could stimulate the salvation of bound extracellular polysaccharides (bEPS) which was adverse to colony formation of Microcystis.

Abstract: The effect of bacterium N1 on the colony formation of the bloom-forming cyanobacterium Microcystis aeruginosa was investigated. The results showed that N1 could induce colony formation in M. aeruginosa in concentration-dependant way. Colony formation can efficiently decrease the damage caused by bacteria through polysaccharides synthesis to maintain the function of photosynthesis apertures.