Table 1.
Comparison of DPPH radical scavenging activity induced by Paenibacillus species and other chitinolytic and/or proteolytic enzyme–producing bacterial strains.
| No. | Bacterial Strain | DPPH Radical Scavenging Activity | |
|---|---|---|---|
| (%) | IC50 (µg/mL) | ||
| 1 | Paenibacillus sp. TKU042 | 94 | 124 ± 13.9 C |
| 2 | Paenibacillus sp. TKU037 | 93 | 138 ± 16.2 C |
| 3 | Paenibacillus sp. TKU036 (positive strain) | 87 | 143 ± 10.3 C |
| 4 | Paenibacillus mucilaginosus TKU032 | 83 | 169 ± 14.2 C |
| 5 | Paenibacillus macerans TKU029 | 88 | 170 ± 20.3 C |
| 6 | Bacillus sp. TKU004 | 56 | 2600 ± 346 B |
| 7 | Bacillus cereus TKU028 | 45 | 3000 ± 288 AB |
| 8 | Bacillus mycoides TKU038 | 44 | 3000 ± 173 AB |
| 9 | Lactobacillus paracasei subsp paracasei TKU010 | 57 | 2700 ± 115 B |
| Control (medium only) | 40 | 3500 ± 289 A | |
| α-Tocopherol (commercial antioxidant) | 95 | 30 ± 5.8 C | |
The tested bacteria were cultivated in 100 mL medium containing 1% SPP at 30 °C, 150 rpm shaking speed for three days. Bacterial mass and medium residues were removed from culture medium solution by centrifugation at 4000 rpm. The supernatants were dried to powders then used for activity detection. Least significant difference (α = 0.1) = 538.97, coefficient of variation = 16.38701, triplicates for each experiment (n = 3), and means of IC50 values with the same letter are not significantly different in comparison based on t-test ranking.