Appendix 12 Bactopeptone test 

(from Bourne, Hodgson and Whyte, 1989)

Materials:
– Bactopeptone.
– Filtered seawater.
– 10 ml tubes with cap.
Procedure:
1. Dissolve 10 g bactopeptone in 1 l filtered seawater.
2. Fill test tubes with 10 ml of media and cap.
3. Autoclave tubes.
4. Inoculate tube containing bactopeptone media with 3–4 drops of algal culture. 5. Store in the dark for up to two weeks..
Assessement:
1. Some faster growing bacteria will become evident within 2–4 days.
2. If bacteria are present, contents of the tube will appear cloudy.
3. Degree of cloudiness reflects degree of bacterial contamination. The cloudier a tube the more contaminated.
4. Discard cultures with heavy bacterial contamination.