TABLE 2.
Enumeration of SRB in a sediment slurry from Kysing Fjord by using different enumeration media and different scoring methods
| Medium | Detection method | MPN · ml−1 on:
|
||
|---|---|---|---|---|
| Day 7 | Day 14 | Day 28 | ||
| Sediment medium | Tracera | 4.2 × 105 (a)c | 4.2 × 106 (a) | 1.5 × 107 (a) |
| Postgate’s B medium | Blackeningb | 2 (b) | 2 (b) | 2.3 × 103 (b) |
| Tracer | 2 (x) | 7 (x) | 2.8 × 102 (x) | |
| Baar’s medium | Blackening | 9.2 × 103 (a) | 9.2 × 103 (c) | 9.2 × 103 (b) |
| Tracer | 7 (x) | 4.0 × 101 (x) | 3.5 × 102 (x) | |
| API-RST medium | Blackening | 9.2 × 103 (a) | 9.2 × 103 (c) | 9.2 × 103 (b) |
| Tracer | 4.2 × 102 (y) | 4.2 × 102 (y) | 3.5 × 103 (x) | |
a
Positive tubes were detected by the 35SO42− T-MPN method, and the detection limit was 0.1% TRIS.
b
Positive tubes were visually detected by the N-MPN method, i.e., by detection of a black precipitate (FeS).
c
MPN values in the same column followed by the same letter are not significantly different as determined by the Student t test (P > 0.05). For comparisons of the T-MPN method with sediment medium and the N-MPN method with synthetic media the letters a, b, and c are used. For comparisons of the T-MPN method with sediment medium and the T-MPN method with synthetic media the letters x and y are used.