Vegetable LB Broth (Lennox)

These strains are generally derived from E. coli K12, which are unable to produce vitamin B, so this medium is formulated to enhance the growth of nutritionally demanding microorganisms. This strain of E. coli has been further modified through specific mutation to create an auxotrophic strain that is not capable of growth on nutritionally deficient media.

In this case, the ingredients are animal-free in order to minimize the risk of bovine spongiform encephalopathy in culture media containing bovine materials. Vegetable origin peptone provides nitrogen, vitamins, minerals and amino acids essential for growth. Yeast extract is a source of vitamins, particularly the B-group, essential for bacterial growth. Sodium chloride supplies essential electrolytes for transport and osmotic balance.

Vegetable LB Broth (Lennox) has a different sodium chloride level than other media such as Luria Broth (Miller LB Broth) (LC-1551) or Luria Broth (Miller’s Modification) (LC-1266). This allows selecting the optimum salt concentration of the medium for a specific strain.

Preparation

Suspend 20 grams of the medium in one liter of distilled water. Mix well and dissolve by heating with frequent agitation. Boil for one minute until complete dissolution and dispense into tubes. Sterilize in autoclave at 121 °C for 15 minutes.

Instructions for use

1. Carry out the experimental procedure according to appropriate use or purpose.
2. Inoculate and incubate at a temperature of 35 ± 2 °C for 18-24 hours.

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