TPY BROTH
CAT Nº: 1591
Selective medium for the isolation of Bifidobacterium
FORMULA IN g/l
Dextrose
15.00
L-Cysteine
0.50
Tryptone
10.00
Magnesium Chloride
0.50
Papainic Digest of Soya
5.00
Zinc Sulfate
0.25
Yeast Extract
2.50
Calcium Chloride
0.15
Dipotassium Phosphate
2.00
Ferric Chloride
0.01
Final pH 6.5 ± 0.2 at 25ºC
PREPARATION
Suspend 36 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. Dispense into appropriate containers and sterilize in autoclave at 121°C
for 15 minutes. The medium can be more selective by adding 3.0 grams of Lithium Chloride, 0.1 grams of Neomycin
Sulfate and 0.015 grams of Nalidixic Acid per liter of medium. The prepared medium should be stored at 2-8°C. The
color of the prepared medium is amber.
The dehydrated medium should be homogeneous, free-flowing and beige in color. If there are any physical changes,
discard the medium.
USES
TPY BROTH is a medium recommended for Bifidobacterium.
The genus Bifidobacterium is the third most numerous bacterial population in the human intestine after the genera
Bacteroides and Eubacterium. It is also the predominant population during childhood. Several Bifidobacterium
species have been incorporated in yogurts, as they are considered to have health-promoting properties (9). The
availability of easy and inexpensive methods for detection, identification, and enumeration of Bifidobacterium is
consequently important in environmental and food microbiology.
Tryptone and Papainic Digest of Soy provide nitrogen, vitamins, minerals and amino acids essential for growth. Yeast
extract is source of vitamins, particularly the B-group. Magnesium chloride, Zinc sulfate, Calcium Chloride and Ferric
Chloride allows the detection of small numbers or injured Bifidobacteria and improves its growth. Potassium phosphates
act as a buffer system. L-Cysteine hydrochloride is the reducing agent.
Inoculate and incubate anaerobically at 35± 2°C during 24 hours.
MICROBIOLOGICAL TEST
The following results were obtained in the performance of the medium, with the additves added, from type cultures after
incubation at a temperature of 35 ± 2ºC and observed after 3 -4 days.
Microorganisms
Bifidobacterium breve ATCC 15700
Growth
Good (the medium is opaque)
Escherichia coli ATCC 25922
Inhibited
Bacillus subtilis ATCC 6633
Inhibited
1
LABORATORIOS CONDA, S.A.
www.condalab.com
BIBLIOGRAPHY
Scardovi V. (1981): The Genus Bifidobacterium. In: The Prokaryotes Vol. 2 eds
A New Selective Medium for Bifidobacterium spp. Y. Nebra* And A. R. Blanch Applied And Environmental Microbiology, Nov. 1999, p.
5173–5176
STORAGE
25ºC
Once opened keep powdered medium closed to avoid hydration.
2ºC
2
LABORATORIOS CONDA, S.A.
www.condalab.com