Contact TVC

(Total Viable Counts) Envirocheck^™

Envirocheck contact total viable count, a semi-quantitative detection of microorganisms on surfaces and in liquids, are flexible paddles that are coated with Nutrient Agar to determine the total viable count of bacteria in sample. Slide A is Coated with Nutrient Agar containing 0.05% Triphenyl Tetrazolium Chloride (TTC) and Slide B Coated with Nutrient Agar. The growth of bacteria on slide A is indicated by red colonies due to the formation of red formazan dye when TTC is reduced.

Envirocheck contact slides can be used for both surface and liquid testing in industrial and environmental monitoring.

Count the number of colonies on both sides of the paddle- results should not differ by a factor greater than 2, where the colonies on side A will appear mainly in red. In the presence of TTC a few microorganisms may grow less profusely. Always go with the higher counts in case they are not identical on both sides. This represents the microbial load for the test.

Sterility: passes test
pH-value/side one (25 °C): 6.7 - 7.3
pH-value/side two (25 °C): 6.7 - 7.3
Growth/side one
- Escherichia coli ATCC 8739 (WDCM 00012):
good
- Staphylococcus aureus ATCC 6538 (WDCM 00032): fair/good
- Candida albicans ATCC 10231 (WDCM 00054): none/poor
- Bacillus subtilis ATCC 6633 (WDCM 00003): good
- Pseudomonas aeruginosa ATCC 9027 (WDCM 00026): good
- Aspergillus brasiliensis (formerly A. niger) ATCC 16404 (WDCM 00053): good
Growth/side two
- Escherichia coli ATCC 8739 (WDCM 00012):
good
- Staphylococcus aureus ATCC 6538 (WDCM 00032): good
- Candida albicans ATCC 10231 (WDCM 00054): good
- Bacillus subtilis ATCC 6633 (WDCM 00003): good
- Pseudomonas aeruginosa ATCC 9027 (WDCM 00026): good
- Aspergillus brasiliensis (formerly A. niger) ATCC 16404 (WDCM 00053): good
Incubation: 48 hrs.; 35 °C; aerobic; Aspergillus up to 72 hrs.

ENVIROCHECK is a trademark of Merck KGaA, Darmstadt, Germany