Application Note – Microbiology N.1 – ANAEROBE MICROBIOLOGY USEFUL INFO
Question 1
How is important the use of specialized anaerobic media?
Answer:
1. Media like Columbia Tryptic Soy, Wilkins Chalgren and Schaedler are unsuitable.
2. Two media are better that one because many anaerobic infections contain more than one type of anaerobe.
3. Incubation should be for a minimum of 48 hours and continue until at least 5 days.
4. The common selective media:
| Genus/Group | Media for use | Concentrations |
| Anaerobic cocci | Nalidixic acid Tween 80 |
10mg/L 0,1% |
| Anaerobic GNRs | Nalidixic acid Vancomycin |
10mg/L 2,5mg/L |
| Clostridia | Neomycin | 100mg/L |
| Actinomyces | Nalidixic acid metronidazole |
30mg/L 10mg/L |
Question 2
Which are the common reasons for the failure of anaerobiosis?
Answer:
- Anaerobe jar leakage
- Poor catalyst activity
- Failure to use biological and chemical indicators
- Wrong biological indicator
- Failure to include CO2 in the anaerobic atmosphere
- The so-called “five o’clock build up”: waiting until the end of the day before incubating anaerobic plates.
Question 3
Which are the common reasons for the failure of anaerobiosis?
Answer:
- Anaerobe jar leakage
- Poor catalyst activity
- Failure to use biological and chemical indicators
- Wrong biological indicator
- Failure to include CO2 in the anaerobic atmosphere
- The so-called “five o’clock build up”: waiting until the end of the day before incubating anaerobic plates.
