ANAEROBE BASAL BROTH

Code: CM0957

A nutrient broth for the growth of anaerobic micro-organisms, particularly Bacteroides spp. and other fastidious anaerobes.

Typical Formula*	gm/litre
Peptone	16.0
Yeast extract	7.0
Sodium chloride	5.0
Starch	1.0
Dextrose	1.0
Sodium pyruvate	1.0
Arginine	1.0
Sodium succinate	0.5
L-cysteine HCl	0.5
Sodium bicarbonate	0.4
Ferric pyrophosphate	0.5
Haemin	0.005
Vitamin K	0.0005
Sodium thioglycollate	0.5
Dithiothreitol	1.0
pH 6.8 ± 0.2 @ 25°C

* Adjusted as required to meet performance standards 

Directions
Suspend 35.4g of Anaerobe Basal Broth in 1 litre of distilled water. Bring to the boil to dissolve. Distribute into final containers. Sterilise by autoclaving at 121°C for 15 minutes.

Description
Oxoid Anaerobe Basal Broth is formulated from a range of nutrients which have been selected to optimise the recovery and growth of the majority of anaerobic organisms of clinical importance.

The formulation includes yeast extract as a source of vitamins and starch is included to absorb toxic products¹. Sufficient arginine is added to ensure growth of Eubacterium lentum ², whilst haemin and vitamin K are present as they are essential for the growth of Bacteroides spp.³. Pyruvate is present as an energy source for asaccharolytic cocci such as Veillonella spp. It also eliminates traces of hydrogen peroxide which may be produced by the action of molecular oxygen on medium constituents⁴. Sodium succinate improves the growth of Prevotella melaninogenica and Bacteroides spp⁵. It is included together with the reducing agent L-cysteine hydrochloride, which has been shown to stimulate directly the growth of some anaerobes⁶.

Technique
It is preferable to use freshly reconstituted and sterile medium which is inoculated as soon as it has cooled to room temperature. Tubes which are not used on the day of preparation should be placed in a boiling water bath or steamer for approximately 15 minutes to remove dissolved oxygen. They should be allowed to cool without agitation and then inoculated. Incubate broths in an appropriate atmosphere.

Storage conditions and Shelf life
Anaerobe Basal Broth should be stored tightly capped in the original container at 10-30°C. When stored as directed, the medium will remain stable until the expiry date printed on the label.

Appearance
Dehydrated medium: Straw coloured, free-flowing powder
Prepared medium: Straw/green coloured solution

Quality control

Positive controls:	Expected results
Peptostreptococcus anaerobius ATCC® 27337*	Turbid growth
Prevotella loescheii ATCC 15930	Turbid growth
Negative control:
Uninoculated medium	No change