LB broth and plate

LB Broth Media Recipe

Standard Recipe for 500mL of LB:



(Sambrook and Russell, 2001 Gerhardt, et al. 1994).

• In a 1L flask, add

H2O 400 mL

Tryptone 5 g


Yeast Extract 2.5 g


NaCl 5 g 



• Adjust pH with NaOH to 7.5

• Top up solution to 500 mL

• Pour into 1L bottle, autoclave using liquid cycle

For LB agar* add agar to a final concentration of 1.5%. (500mL~7.5g 100mL~1.5g)

• Autoclave (Liquid cycle)

• Wait till the bottle is comfort to touch (~40 c), adds the 1000x Amp, mix.

• Pour the plates

• Surround the plates under the ethanol burner, leave lids slightly open.

• Wait will the agar is set, label “Amp+, date”, wrap with parafilm, store in the fridge lids down.

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