Overview:
Brucella Broth is the international reference liquid medium for the cultivation, enrichment, and maintenance of all Brucella species (B. melitensis, B. abortus, B. suis, B. canis, B. ovis, B. neotomae, B. microti, etc.). It is also widely used for Francisella tularensis, Haemophilus spp., and other fastidious pathogens. It is the base for selective Brucella enrichment broths (e.g., with antibiotics or serum).
Applications:
Blood culture enrichment for Brucella (especially in automated systems)
Subculture and maintenance of Brucella isolates
Growth for antigen, DNA, and biochemical testing
Base for selective liquid media (Farrell�s broth, Casta�eda bottles)
Official reference in OIE, CLSI M45, and WHO guidelines
Key Features:
Extremely rich formulation ? supports growth from very low inocula
Clear broth ? easy detection of light turbidity
Stable for long incubation periods (up to 6 weeks)
Composition (per liter � standard formulation):
Tryptose/Trypticase Peptone 10.0 g
Peptone 10.0 g
Yeast Extract 2.0 g
Glucose 1.0 g
NaCl 5.0 g
Sodium Bisulfite 0.1 g
Final pH: 7.0 � 0.2 at 25�C
Optional enrichment (commonly added):
5�10 % sterile horse/sheep serum (increases recovery)
1�2 % sodium citrate (for Casta�eda biphasic system)
Preparation:
Dissolve 28.1 g dehydrated base in 1 L purified water.
Mix thoroughly.
Dispense into tubes or bottles (5�50 mL).
Autoclave at 121�C for 15 minutes.
(Optional) Add sterile serum aseptically after cooling.
Incubation:
35�37�C, 5�10 % CO?, up to 6 weeks (check weekly).
Positive: light to moderate turbidity, sometimes with granular sediment.
Storage:
Dehydrated base: cool, dry place below 30�C
Prepared broth: 2�8�C, use within 6 months
Biosafety: Brucella is Risk Group 3 � handle under BSL-3 conditions.
Reference: OIE Terrestrial Manual (2022), CLSI M45-A3, Alton et al. (1988).