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2.3.1.1: Making Media (LB Broth and Agar)

  • Page ID
    114842
    • Nathan Reyna, Ruth Plymale, & Kristen Johnson
    • Ouachita Babtist University & University of New Hampshire

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    LB Agar:

    Making 1 L of LB Agar:

    • 5 g Yeast extract
    • 10 g Peptone
    • 10 g NaCl
    • 12 g Agar
    1. Mix this with 1 L of Distilled H2O
    2. Autoclave at 121 °C for 30 minutes (If there is a setting, set it to slow/liquid)
    3. Let cool before pouring into plates (approximately 25 mL of agar in each plate)

    This recipe makes about 40 plates and can be adjusted as needed!

    LB Broth:

    Making 1 L of LB Broth:

    • 25 g pre-mixed broth powder

    *This powder contains 10 g tryptone, 5 g yeast extract and 10 g NaCl*

    1. Mix this with 1 L of Distilled H2O
    2. Autoclave at 121 °C for 30 minutes (If there is a setting, set it to slow/liquid)
    3. Let cool before pouring into STERILE test tubes with lids (approximately 5 mL of broth per test tube)

    This recipe makes about 200 tubes of broth and can be adjusted as needed!


    This page titled 2.3.1.1: Making Media (LB Broth and Agar) is shared under a not declared license and was authored, remixed, and/or curated by Nathan Reyna, Ruth Plymale, & Kristen Johnson.