I am working on this as my collage major project can any one pleasure help he
Hi Dear Bibek Gupta
I hope files that i attached here, could be helpful for you.
I share with you the approach and values examined related to your question as follows. I hope it be helpful for you.
Four strains of alkaliphilic spore-forming bacteria ca be purchased from DSMZ (German Collection of Microorganisms and Cell Cultures), Braunschweig, Germany: Sporosarcina pasteurii DSM 33; Bacillus cohnii DSM 6307; Bacillus halodurans DSM 497 and Bacillus pseudofirmus DSM 8715 and to be cultivated according to the suppliers recommendations (medium DSMZ-2 for S.pasteurii and DSMZ-31 for the others). Endospore-forming potential is determined in mineral medium. This medium contained per liter of Milli-Q ultra pure water: 0.2g NH4Cl, 0.02g KH2PO4, 0.225g CaCl2, 0.2g KCl, 0.2g MgCl2.6H2O, 1 ml per liter trace elements solution SL12B, 0.1g yeast extract, 6.45g citric acid trisodium salt and 8.4g sodium bicarbonate. The pH of this medium is 9.2. Aerobic batch cultures are incubated in 2-l Erlenmeyer flasks on a shaker table at 150 rpm. Growth is monitored by microscopy and cell numbers and percentage of sporulating cells are quantified by microscopy using a Burger-Turk counting chamber.
To examine the calcite precipitation potential of bacterial concrete follow the following steps and apply similar values of in the conditions of temperature and time duration mentioned bellow: Chips of 10 days cured cement stone samples to be incubated in rich medium (yeastextract and peptone based medium) after pasteurizing for 30 min at 70ºC. Pasteurization of bacterial and control cement stone chips before incubation is to be done to inactivate bacteria that potentially that comes into contact with the cement stone samples during curing period or non-sterile handling of the cement stone samples and chips after curing. As bacterial endospores are not killed by the pasteurization procedure, this treatment ensured that potential differences between control and bacterial concrete samples after incubation are mediated by added bacteria and not by accidentally introduced contaminants. Rich medium contained 5 g peptone, 3 gram yeast extract and 8.4 g sodium bicarbonate and have a pH of 8.6. Individual chips should be incubated aerobically in 100-ml medium aliquots on a shaker table at 100 rpm at 25ºC for 12 days. Chips should be rinsed with tap water after incubated and stored wet in closed plastic vials until ESEM analysis, what is to be done within two days after incubation without any further treatment. Chips should be mounted on a 1-cm2 metal support and to be kept in place with adhesive tape and observed with a Philips XL30 Series Environmental Scanning Electron Microscope.
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