Potato Dextrose Broth


Cat. No. 1.00510.0500
 (500 g)


Medium for the cultivation of yeast and molds.


Mode of Action Quality Control
Typical Composition (g/liter) Preparation
Literature Experimental Procedure and Evaluation


Mode of Action
 Potato Dextrose Broth is a general medium for yeasts and molds. Bacterial growth is inhibited by the low pH. The formulation is identical to Potato Dextrose Agar with no agar included.

Typical Composition (g/liter)
 Potato infusion (infusion from 200g potatoes) 4.0; Dextrose 20.0.

Preparation
 Suspend 24.0 g in 1 liter of purified water. Heat to boiling with frequent agitation to dissolve completely. Autoclave for 15 min. at 121°C. Fill into test tubes as necessary.

pH: 5.1 ± 0.2 at 25°C

The broth is clear to slightly opalescent and yellowish in color.


Experimental Procedure and Evaluation
 Inoculate the broth according to the apropriate method concerning processing and inoculation. Incubate for 44 ± 4 hours at 25 ± 2°C. Check cultures for growth indicated by turbidity. Incubation may be continued for a period of up to 7 days because of slow growers (e.g., T.mentagrophytes).


Quality control

Test strains
 Inoculum (cfu/10 ml)
 		Growth after 48 hours
Candida albicans ATCC 10231
 		102-103
 		+
Saccharomyces cerevisiae ATCC 9763
 		102-103
 		+
Aspergillus niger ATCC 16404
 		102-103
 		+




Literature
Atlas, R.M.: Handbook of Microbiological Media, second edition. Lawrence C. Parks (1997)
MacFaddin, J. F.: Media for isolation-cultivation-maintenance of medical bacteria, vol 1. Williams & Wilkins, Baltimore/MD. (1985).


© 2002 Merck KGaA, Darmstadt, Germany