Category: Bacterial Growth Media
Preparation of Lambda-agar medium and plates
Lambda-agar is nothing but a lambda broth which is solidified by agar. Agar is a solidifying agent. It melts at 85°C but melton agar stays liquid at a temperature > 40°C (this property is called hysteresis, different temperatures for melting and solidifying). This allows us to add heat-labile medium supplements such as antibiotics and vitamins and prepare solid medium. Lambda-agar solid medium is prepared by dissolving 15 g agar / liter of Lambda broth.
Preparation of SOC (Super Optimal broth with Catabolite repression) Medium
SOC (Super Optimal broth with Catabolite repression) medium is a nutrient-rich microbial growth medium, formulated by Douglas Hanahan in 1983 (Hanahan, 1983). SOC medium is prepared without Mg++ and Glucose by dissolving 20 g bacto-tryptone, 5 g bacto-yeast extract, 2 ml of 5M sodium chloride, and 2.5 ml of 1M KCl in water to a final volume of ≈ 1000 ml (960 ml). Magnesium salts (i.e., MgSO4 and MgCl2, 10 ml each of 1M MgSO4 and 1M MgCl2) and Glucose (10 ml of 1 M Glucose) are added to the medium after autoclaving to prevent any chemical reactions and precipitation of the medium components, and degradation of Glucose.
Preparation of LB Luria Broth
LB is a rich growth medium, commonly used to grow E. coli. LB Luria Broth contains 1% Bacto-tryptone, 0.5% Bacto-yeast extract and 0.05% Sodium chloride. A 1000 ml LB Luria Broth is prepared by dissolving 10 g Bacto-tryptone, 5 g Bacto-yeast extract and 0.5 g sodium chloride in deionized water to a final volume of 1000 ml. After adjusting the pH 7.0 with 5N NaOH medium is autoclaved and stored in a cold room.
Preparation of LB Lennox Broth
LB medium is a rich growth medium, commonly used to grow E. coli. LB, Lennox Broth contains 1% Bacto-tryptone, 0.5% Bacto-yeast extract and 0.5% Sodium chloride. A 1000 ml LB, Lennox Broth is prepared by dissolving 10 g Bacto-tryptone, 5 g Bacto-yeast extract and 5 g sodium chloride in deionized water to a final volume of 1000 ml. After adjusting the pH 7.0 with 5N NaOH medium is autoclaved and stored in a cold room.