Description
General description
Malt extract agar is recommended for the detection, isolation, and enumeration of yeasts and molds. The acidic pH of the medium supports the growth of Yeasts and Molds while it suppresses the growth of bacterial flora. The addition of certain indicator dyes to the medium allows differentiation of yeast and bacterial colonies. Furthermore, a modified malt extract agar is recommended for the selective cultivation of Aspergillus flavus.
Application
Malt extract agar is used for the detection, isolation, and enumeration of fungi, particularly yeasts and molds, in various materials and for the cultivation of test strains for the microbiological vitamin assays.
Analysis Note
Appearance (clearness): clear to slightly opalescent
Appearance (color): brown
pH-value (25 °C): 5.4 - 5.8
Growth promotion test in accordance with the current version of DIN EN ISO 11133.
Inoculum on reference medium (Candida albicans ATCC 10231 (WDCM 00054)):
Inoculum on reference medium (Saccharomyces cerevisiae ATCC 9763 (WDCM 00058)):
Inoculum on reference medium (Saccharomyces cerevisiae ATCC 9080):
Inoculum on reference medium (Rhodotorula mucilaginosa DSM 70403):
Colony count (Candida albicans ATCC 10231 (WDCM 00054)):
Colony count (Saccharomyces cerevisiae ATCC 9763 (WDCM 00058)):
Colony count (Saccharomyces cerevisiae ATCC 9080):
Colony count (Rhodotorula mucilaginosa DSM 70403):
Recovery on test medium (Candida albicans ATCC 10231 (WDCM 00054)): ≥ 70 %
Recovery on test medium (Saccharomyces cerevisiae ATCC 9763 (WDCM 00058)): ≥ 70 %
Recovery on test medium (Saccharomyces cerevisiae ATCC 9080): ≥ 70 %
Recovery on test medium (Rhodotorula mucilaginosa DSM 70403): ≥ 70 %
Growth (Geotrichum candidum DSM 1240): good to very good
Growth (Penicillium commune ATCC 10428): good to very good
Growth (Aspergillus brasiliensis (formerly A. niger) ATCC 16404 (WDCM 00053)): good to very good
Growth (Trichophyton ajelloi ATCC 28454): moderate to good
Incubation: Molds 7 days at 26 ± 2 °C, Yeasts 3 days, aerobic
A recovery rate of 70 % is equivalent to a productivity value of 0.7.
The indicated colony counts result from the sum of a triple determination.
Reference media: SABOURAUD Agar
Legal Information
GRANUCULT is a registered trademark of Merck KGaA, Darmstadt, Germany
NutriSelect is a registered trademark of Merck KGaA, Darmstadt, Germany
Disclaimer
We offer two media types: the superior granulated GranuCult® and the cost-efficient powdered NutriSelect® culture media, depending on your needs. The designations basic, plus, or prime are added to indicate the quality control level, from basic quality control to standard QC plus to prime for full regulatory compliance.
