Table 3 Effect of pH, heat, and enzyme treatment on the antibacterial activity of crude bacteriocin of Lactobacillus gasseri G2
| Treatment | Residual activity |
| pH | 2 | ++++ |
| 4 | ++++ |
| 6 | ++++ |
| 7 | ++++ |
| 8 | ++++ |
| 9 | ++++ |
| 10 | ++++ |
| 11 | +++ |
| Heat (temperature, °C) | 4 (24 h) | ++++ |
| 25 (24 h) | ++++ |
| 30 (24 h) | ++++ |
| 37 (24 h) | ++++ |
| 50 (24 h) | ++++ |
| 70 (24 h) | ++++ |
| 100 (30 min) | ++++ |
| 121 (15 min) | ++++ |
| Enzymes | α-Amylase | ++++ |
| Lipase | ++++ |
| Lysozyme | ++++ |
| Proteinase K (2 mg/mL) | - |
| Protease (2 mg/mL) | - |
| Trypsin (2 mg/mL) | - |
| Organic solvents | Culture broth | ++++ |
| Acetone | ++++ |
| Methanol | ++++ |
| Ethanol | ++++ |
| Butanol | ++++ |
- : no clear zone; + : ≤ 6 mm; ++: 6.1 mm≤clear zone ≤ 10.1 mm; +++: 10.1 ≤ clear zone ≤ 14.1 mm, ++++ ≥ 14.2 mm