POTATO DEXTROSE BROTH

Technical Data # 39-3607a / 2010.08.30

Potato Dextrose Broth is used for the cultivation of yeast and molds.

 

FORMULA
in grams per litre purified filtered water

Dextrose.......................................20.0 g

Potato infusion from solids............6.5 g

pH 5.6 ± 0.2 at 25°C

This approximate formula may be adjusted and/or enriched to obtain best results.


PRECAUTIONS
This medium is for laboratory use only.


STORAGE
Store prepared media at 2-30° C protected from direct light and dehydrated powder, in a dry place, in tightly-sealed containers at 2-25° C.


SIGN OF DETERIORATION
Media should not be used if the expiry date has passed. Prepared media should not be used if there are signs of contamination or deterioration (shrinking, cracking, evaporation or discoloration). Do not use dehydrated media if it is caked.

DIRECTIONS

Suspend 26.5 grams of the medium in 1000 mL of distilled purified water.  Boil for one minute and sterilize at 118 - 121°C for 15 minutes.

PROCEDURE

Inoculate the medium and incubate at 30 ± 2°C for 48 - 72 hours. Growth is indicated as turbidity.

QUALITY CONTROL 

The  following results were  obtained  in the  performance of the  medium  from  type  cultures after  incubation  at  a temperature of 30 ± 2°C and observed after  3 days.

Microorganisms               ATCC             Growth

Aspergillus  niger            16404               Good

Candida  albicans            10231              Good

Saccharomyces cerevisiae   9763              Good

 

LIMITATIONS OF METHOD
This medium is only a part of the identification. Other tests may be required.


REFERENCES

1 - Association of Official Analytical Chemists.  1995. Bacteriological  analytical manual, 8th ed. AOAC International, Gaithersburg, MD. MacFaddin,  J.F.  1985. Media  for  isolation-cultivation-identification-maintenance  of  medical  bacteria,  vol. 1 Williams  &  Wilkins, Baltimore, MD.

2 - Frank, J.F. G.L. Christen, and L.B. Bullerman (G.H. Richardson, Tech. Comm.) 1993. Tests for groups of microorganisms. P. 271-286. In Marshall, R.T. (ed.). Standard methods for the microbiological examination of dairyproducts, 16thed. American Public Health Association, Washington, D.C.

CATALOGUE NUMBER

Deshydrated medium              500 g                QB-39-3607