Page 190 - Demo

194 PROCEEDINGS OF INTERNATIONAL SCIENTIFIC CONFERENCE ON APPLIED BIOTECHNOLOGY(Hansen, g/L): glucose 50.0 g/L peptone 10.0 g/L K2HPO4 3.0 g/L MgSO4.7H2O 2.0 g/L distilled water 1000 mL.2.2. Methods Isolation of bacteria from Nai Lagoon sediment samples: Each sediment sample was weighed 10 g and crushed in a porcelain mortar and pestle (sterilized). Then dissolved in 90 mL sterile saline (0.85% NaCl), shaken at 150 rpm for 10 - 20 minutes, left to settle for 15 minutes, and then pipetted 1 mL of the solution into a test tube with 9 mL of new saline. Continue to dilute to 10-4and 10-5. From each dilution concentration, pipetted 1 mL of the culture solution onto a petri dish containing marine and coastal bacteria isolation media (MA, OLIGO, SCA, AIA, KA, MI, Gauze I, Gauze II), incubated at 30 oC, for 1 - 5 days to observe the growth of the colonies, purify and store the strain at -80 oC.Screening for antibacterial, antifungal activity of bacterial isolates: Antibacterial/ antifungal activity was evaluated by the agar well diffusion method, according to the method of Flemer et al. (2012) [8], with modifications suitable to the experience of the researcher performing the experiment and the laboratory conditions. The antibacterial/ antifungal zone was determined according to the formula: Antibacterial/ antifungal inhibition zone = D - d (mm)In which: D: Diameter of antibacterial/ antifungal zoned: Diameter of agar hole.Screening for anticancer activity of bacterial isolates: The previously tested antibacterial bacterial extracts were subjected to 96 healthy plate cytotoxicity screening on MCF-7 breast cancer cells, Hep G2 liver cancer cells, and HEK 293T normal cells by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) method according to Monks et al. (1991) [9]. The cell lines were