Table 5 Residual emulsification activity (REA%) under different thermal treatments after an incubation period of up to 30 months
Isolate/surfactant | Time (months) | 4 °C | 55 °C | Autoclave treatment | |||||
|---|---|---|---|---|---|---|---|---|---|
Toluene | Hexane | Toluene | Hexane | Hexadecane | Toluene | Hexane | Hexadecane | ||
Tween 80 | 29 | 91.27 ± 0.28 | 93.50 ± 1.33 | 0.00 ± 0.00 | 0.00 ± 0.00 | 0.00 ± 0.00 | 90.38 ± 1.29 | 77.78 ± 0.00 | 0.00 ± 0.00 |
Bacillus sp. L45 | 30 | 95.03 ± 5.14 | 100.00 ± 0.00 | 72.08 ± 0.92 | 56.41 ± 6.81 | 51.49 ± 8.00 | 66.79 ± 6.57 | 86.15 ± 8.70 | 0.00 ± 0.00 |
Paenibacillus tarimensis L88 | 30 | 62.50 ± 8.84 | 0.00 ± 0.00 | 0.00 ± 0.00 | na | na | na | na | na |
Bacillus sp. L97b | 29 | 92.26 ± 1.52 | 92.72 ± 5.42 | 75.00 ± 3.75 | 90.42 ± 0.00 | 0.00 ± 0.00 | 28.57 ± 0.00 | 81.25 ± 4.06 | 0.00 ± 0.00 |
Bacillus sp. L98 | 29 | 79.41 ± 8.32 | 83.29 ± 4.13 | 0.00 ± 0.00 | 0.00 ± 0.00 | nt | 0.00 ± 0.00 | 79.48 ± 6.33 | nt |
Bacillus sp. R4p | 29 | 92.08 ± 2.37 | 77.05 ± 2.90 | 0.00 ± 0.00 | 0.00 ± 0.00 | na | 0.00 ± 0.00 | 0.00 ± 0.00 | na |
Bacillus sp. R55 | 29 | 83.95 ± 8.72 | 68.40 ± 8.86 | 79.40 ± 8.94 | 77.59 ± 3.88 | 88.67 ± 4.43 | 97.94 ± 1.97 | 100.00 ± 0.00 | 0.00 ± 0.00 |