LB Broth & LB Agar
LB Broth is a common bacterial growth media, or "food". It contains NaCl, water, yeast, tryptone, and bactopeptone. It can also contain agar, allowing it to be used to pour agar plates for bacterial growth and experimentation. The procedure we used to prepare our agar plates is below.
Preparation of LB Agar
1) Fill 2 Erlenmeyer flasks (to account for water
loss during boiling) with approximately 500mL of distilled water.
2) Heat until boiling
3) Add BIO-RAD LB Agar Powder (500mL packet, Control 117298, Catalog 166-0600)
in small amounts, swirl to dissolve. If powder does not completely
dissolve, heat the solution.
4) The end product should appear a deep, translucent yellow in color, similar to
the color of beer.
5) After cooling, LB agar was poured into Petri dishes to make agar plates.
6) If there will be additives (i.e., arabinose and ampicillin) to any of the
plates, add before they have completely formed into an agar gel.