Minerals Modified Glutamate Medium

Originally intended for enumeration of coliforms in water samples, a medium containing glutamic acid was devised by Folpmers and further developed by Gray as a potential replacement for MacConkey Broth.
Later, Gray modified the medium to incorporate a variety of minerals promoting improved lactose fermentation by coliforms and Escherichia coli.
Minerals Modified Glutamate Medium is suitable for the enrichment of low levels of coliforms and recovery of chlorine-damaged bacteria.

Minerals Modified Glutamate Medium is recommended by the Standing Committee of Analysts and International Organization for Standardization.
It is tested in accordance with ISO 11133:2014.

Additional Information

Shelf Life (days)	1095 days
Storage Temp (°C)	10-30°C
Dehydrated Medium Appearance	Fine Powder
Prepared Medium Appearance	Liquid
Dehydrated Medium Colour	Purple
Prepared Medium Colour	Purple
Prepared PH	6.7 ± 0.2
Recommended Incubation	Aerobically at 37 ± 1°C for 24 ± 2 hours. Visual colour checks should be performed at 24 hours.

Product Description

Organisms	Ref. No	Result
Escherichia coli	NCTC 12241	Broth: Growth, yellow with acid and gas production.
Escherichia coli	NCTC 12923	Broth: Growth, yellow with acid and gas production.
Klebsiella aerogenes	NCTC 10006	Broth: Growth, yellow with acid and gas production.
Pseudomonas aeruginosa	NCTC 12903	Broth: Growth, purple with no acid or gas production.
Enterococcus faecalis	NCTC 775	Broth: Inhibited, purple with no acid or gas production.
Enterococcus faecalis	NCTC 12697	Broth: Inhibited, purple with no acid or gas production.

Recommended incubation: Aerobically at 37 ± 1°C for 24 ± 2 hours.
Visual colour checks should be performed at 24 hours.

Formula

Lactose	20
Dipotassium hydrogen phosphate	1.8
Sodium formate	0.5
L-cysteine	0.04
L-aspartic acid	0.048
L-arginine	0.04
Thiamine	0.002
Nicotinic acid	0.002
Pantothenic acid	0.02
Magnesium sulphate	0.02
Ferric ammonium citrate	0.02
Calcium chloride	0.02
Bromocresol purple	0.02
Total	22.69

Preparation

For the preparation of double strength* medium:

Suspend 22.69g of dehydrated culture medium (KM0213) in 1 litre deionised/purified water.

Add 5g of ammonium chloride and 12.7g of L-glutamic acid sodium salt.

Heat with frequent agitation and boil for one minute to completely dissolve the powder.

Dispense specified volume into appropriate containers; an inverted Durham tube may be added to visualise gas production.

Autoclave to sterilise at 115°C for 10 minutes before cooling in a water bath.

*For single strength medium, use half of the above stated amounts in 1 litre of deionised/purified water.

Minerals Modified Glutamate Medium