Table 1.
Production of organic acids by Viridibacillus arenosi strain IHB B 7171 during TCP, Al–P and Fe–P solubilization under different stress parameters
| Parameter | Organic acids production (µg/ml) | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| TCP | Al–P | Fe–P | ||||||||
| Final pH | GA | LA | OA | SA | GA | OA | GA | OA | ||
| pH | 5 | 3.9 | 217.8 | 629.3 | 117.8 | 434.3 | 16.2 | 125.3 | 24.8 | 14.8 |
| 6 | 4.1 | 1022.1 | 952.4 | 122.1 | 46.4 | 22.4 | 806.5 | 24.7 | 24.7 | |
| 7 | 3.9 | 1125.2 | 722.1 | 125.2 | 172.1 | 55.7 | 822.1 | 34.4 | 24.2 | |
| PEG 6000 (%) | 10 | 4.2 | 16.2 | 345.3 | 342.4 | ND | 16.8 | 111.3 | ND | ND |
| NaCl (%) | 2.5 | 4.1 | 211.9 | 132.3 | 56.6 | ND | ND | ND | ND | ND |
| CaCl2 (mM) | 2.5 | 4.0 | 121.9 | 154.3 | 111.3 | ND | ND | ND | ND | ND |
| AlCl3 (mM) | 2.5 | 3.8 | 168.8 | 111.7 | 14.9 | ND | ND | ND | ND | ND |
| FeCl3 (mM) | 2.5 | 3.9 | 145.9 | 15.4 | 29.4 | ND | ND | ND | ND | ND |
Values are the mean of three replicates and significantly different from the control at p < 0.05
ND not detected, TCP tricalcium phosphate, Al–P aluminium phosphate, Fe–P iron phosphate. OA oxalic acid, GA gluconic acid, SA succinic acid, LA lactic acid