Table 1 Summary of PBD for AuNPs biosynthesis, using Bacillus subtilis NRC1 extracellular filtrate.
Independent Factor | Symbol | Units | Levels | ||
|---|---|---|---|---|---|
−1 | 0 | 1 | |||
Casein hydrolysate | A | % | 0.16 | 0.44 | 0.72 |
Dextrin | B | % | 1 | 2.5 | 4 |
Initial pH | C | _ | 6 | 7 | 8 |
Incubation period | D | days | 1 | 3 | 5 |
Inoculum size | E | CFU × 106/ml | 56 | 168 | 280 |
Temperature | F | \(^\circ\)C | 20 | 30 | 40 |
