LB is the most widely applied bacterial medium in molecular biology. It can be used for the cultivation of bacteria including Escherichia coli, Pseudomonas putida, Vibrio parahaemolyticus, and Bacillus spp. It is easy to prepare and nutrient-rich, containing polypeptides, amino acids, water-soluble vitamins and carbohydrates, and is applicable to experiments such as gene cloning, plasmid DNA preparation and recombinant protein production. High-density LB medium is specially developed for Escherichia coli culture using refined tryptone and yeast extract. It contains more abundant nitrogen sources, polypeptides and amino acids than conventional LB medium. When culturing cloning strains such as DH5α, the cell yield and plasmid yield are approximately 50% higher than those of conventional LB; when culturing prokaryotic expression strains such as BL21 (DE3), its cell yield is 20%–50% higher than conventional LB.
Product Components and Formulation：
| Product Components | Formula of High-Density LB Broth (g/L) | Formula of High-Density LB with Agar (g/L) | Concentration | | Tryptone | 10 g | 10 g | 1% | | Yeast Extract | 5 g | 5 g | 0.50% | | NaCl | 10 g | 10 g | 1% | | Agar | — | 15 g | 1.50% |
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Usage Instructions：
High-Density LB Broth Powder Medium: Dissolve one pouch (12.5 g) of LB Broth powder medium in 450 mL double-distilled water, then adjust the volume to 0.5 L. Sterilize by autoclaving at 121°C for 20 min. Use after the temperature drops below 40 °C post sterilization.
Precautions：
1. The pH value of this product is 7.0±0.1 at 25 °C. When mixed with deionized water at pH 7.0, the final pH is close to 7.0, so pH adjustment is not required before use.
2. LB medium must be diluted with water first and autoclaved at 121 °C for 20 min prior to use. Discontinue use if severe moisture absorption is observed.
3. High-Density LB medium supports faster growth of Escherichia coli, with a growth rate approximately 20% higher than standard LB medium.
4. For preparations smaller than 0.5 L, add 2.5 g medium powder per 100 mL water proportionally. Seal leftover powder and store in a dry environment.
5. This product is for research use only. Do not use it for medical diagnosis, clinical treatment, food, cosmetics or other related applications. Do not store in residential areas.
6. Our company shall not be liable for any accidents caused by improper use of this product.
