Modified Baar’s Medium Base (Without Ammonium Ferrous Sulfate)

Modified Baar’s Medium Base (without ammonium ferrous sulfate) is specifically designed for the cultivation of Desulfovibrio and other sulfate-reducing bacteria (SRB). This basal medium provides the essential nutrients for SRB growth, and upon supplementation with 35% sodium lactate solution, it creates an optimal environment for studying microbial sulfate reduction and anaerobic metabolism.

Applications:

• Cultivation of Desulfovibrio species and other sulfate-reducing bacteria

• Microbial sulfate reduction studies

• Environmental and wastewater microbiology research

• Anaerobic microbial physiology and metabolic pathway investigations

Specifications:

• Form: Powder, 250 g/bottle

• Storage: Room temperature

• Shelf Life: 3 years

Formula (per liter):

• Sodium citrate – 5.0 g

• MgSO₄ – 2.0 g

• CaSO₄ – 1.0 g

• NH₄Cl – 1.0 g

• Yeast Extract – 1.0 g

• Final pH: 7.5 (adjust after sterilization, 25℃)

Preparation Instructions:

1. Suspend 10.0 g of the medium in 1 liter of distilled or deionized water.

2. Heat to boiling until completely dissolved.

3. Dispense into suitable containers.

4. Sterilize by autoclaving at 121℃ for 15 minutes.

5. Cool to 55℃.

6. Add 1 ampoule (0.35 g) of 35% sodium lactate solution (with 0.05 g K₂HPO₄) per 100 mL medium.

7. Mix thoroughly under aseptic conditions.

8. Adjust pH to 7.5 (25℃) with sterile sodium carbonate or dilute hydrochloric acid.

9. Use under sterile and anaerobic conditions.