Nisin Z Production by Wild Strains of Lactococcus lactis Isolated from Brazilian (Italian Type) Fermented Sausage
Table 1
Effect of nitrogen source, initial pH, temperature, and aerobic and anaerobic conditions on the production of nisin Z by Lactococcus lactis strains ID1.5, ID3.1, ID8.5, PR3.1, and PD4.7 strains.
Conditions tested
Antimicrobial activity (AU·mL−1)
ID1.5
ID3.1
ID8.5
PR3.1
PD4.7
Tryptone
125000
114000
91000
74000
57000
Animal peptone
57000
62000
51000
49000
40000
Soy peptone
23000
34000
14000
30000
34000
Casein peptone
91000
137000
57000
125000
114000
Meat extract
8600
9200
4300
5700
4300
Yeast extract
12800
12800
9300
11000
4300
Initial pH
4.5
6400
12800
10000
12000
4200
5.0
31000
26000
20000
23000
13000
5.5
34000
32000
46000
40000
52000
6.0
80000
114000
114000
137000
137000
6.5
91000
91000
114000
114000
80000
7.0
13000
20000
23000
16000
17000
Temperature (°C)
20
7000
6000
5000
7000
4000
25
14000
17000
17000
13000
10000
30
14000
17000
19000
14000
10000
35
6400
10000
7000
9000
3000
40
400
300
300
400
300
Aerobiose
46000
31000
51000
46000
40000
Anaerobiose
31000
17000
14000
13000
11000
All experiments were performed in triplicate, and the averages of two independent tests were calculated.