Table 5 Effect of yeast extract, metal ions and physical factors on protease (Uml-1) production (A) and bacterial growth (B) at pH 9.0, 25°C and 150 rpm during 96 h incubation
Yeast extract and metal ions (%, w/v) | Incubation Time (h) | ||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Yeast extract | 12 | 24 | 36 | 48 | 60 | 72 | 84 | 96 | |||||||||
A | B | A | B | A | B | A | B | A | B | A | B | A | B | A | B | ||
Yeast extract | (0.0) | 9 | 0.96 | 17 | 2.41 | 28 | 3.21 | 41 | 3.52 | 66 | 3.74 | 89 | 3.66 | 84 | 3.60 | 81 | 3.51 |
Yeast extract | (0.1) | 14 | 1.08 | 31 | 2.40 | 52 | 3.40 | 76 | 3.75 | 93 | 3.84 | 110 | 3.72 | 108 | 3.65 | 105 | 3.61 |
Yeast extract | (0.2) | 17 | 1.16 | 54 | 2.47 | 67 | 3.46 | 103 | 3.82 | 154 | 3.95 | 178 | 3.81 | 170 | 3.74 | 159 | 3.69 |
Yeast extract | (0.3) | 20 | 1.18 | 65 | 2.49 | 92 | 3.67 | 152 | 4.21 | 203 | 4.38 | 219 | 4.20 | 213 | 4.14 | 208 | 4.07 |
Yeast extract | (0.4) | 28 | 1.21 | 79 | 2.53 | 109 | 3.79 | 167 | 4.63 | 227 | 4.77 | 255 | 4.64 | 246 | 4.58 | 239 | 4.50 |
Yeast extract | (0.5) | 29 | 1.23 | 84 | 2.62 | 115 | 3.84 | 182 | 4.71 | 239 | 4.96 | 278 | 4.87 | 269 | 4.80 | 251 | 4.71 |
Yeast extract | (0.6) | 26 | 1.30 | 67 | 2.97 | 105 | 4.11 | 178 | 4.91 | 231 | 5.17 | 269 | 5.04 | 257 | 4.97 | 248 | 4.91 |
Yeast extract | (0.7) | 21 | 1.39 | 48 | 3.16 | 92 | 4.50 | 163 | 5.20 | 227 | 5.35 | 246 | 5.26 | 241 | 5.18 | 237 | 5.03 |
Metal ions | |||||||||||||||||
No metal | 29 | 1.23 | 84 | 2.62 | 115 | 3.84 | 182 | 4.71 | 239 | 4.96 | 278 | 4.87 | 269 | 4.80 | 251 | 4.71 | |
ZnSO4 | (0.01) | 6 | 1.34 | 17 | 3.62 | 36 | 4.93 | 67 | 5.82 | 92 | 6.05 | 103 | 5.87 | 100 | 5.54 | 94 | 5.17 |
CuSO4 | (0.01) | 5 | 0.51 | 12 | 1.32 | 41 | 2.15 | 98 | 2.62 | 159 | 2.94 | 186 | 2.77 | 182 | 2.61 | 174 | 2.54 |
FeCl2 | (0.01) | 8 | 0.62 | 31 | 1.40 | 74 | 1.95 | 154 | 2.17 | 186 | 2.31 | 210 | 2.27 | 207 | 2.08 | 201 | 1.83 |
MnSO4 | (0.01) | 4 | 0.82 | 15 | 1.43 | 34 | 3.05 | 78 | 3.67 | 133 | 4.15 | 147 | 3.94 | 145 | 3.80 | 141 | 3.64 |
CaCl2 | (0.01) | 33 | 1.16 | 86 | 3.08 | 143 | 4.60 | 196 | 5.23 | 289 | 5.82 | 342 | 5.53 | 336 | 5.38 | 327 | 4.94 |
MgSO4 + CaCl2 | (0.005 + 0.005) | 36 | 1.19 | 92 | 2.97 | 158 | 4.82 | 209 | 5.34 | 318 | 5.95 | 377 | 5.76 | 372 | 5.60 | 364 | 5.23 |
MgSO4 | (0.005) | 36 | 1.23 | 77 | 2.86 | 159 | 3.90 | 216 | 5.69 | 297 | 5.91 | 354 | 5.57 | 349 | 5.21 | 342 | 5.19 |
MgSO4 | (0.01) | 41 | 1.20 | 106 | 3.10 | 197 | 4.73 | 304 | 6.07 | 386 | 6.18 | 431 | 6.10 | 428 | 5.83 | 417 | 5.26 |
MgSO4 | (0.02) | 38 | 1.80 | 81 | 4.13 | 175 | 5.20 | 286 | 6.22 | 364 | 6.38 | 378 | 6.15 | 376 | 6.03 | 371 | 5.86 |
MgSO4 | (0.03) | 35 | 1.62 | 62 | 3.57 | 139 | 5.14 | 246 | 6.11 | 327 | 6.15 | 356 | 5.96 | 352 | 5.81 | 346 | 5.66 |
MgSO4 | (0.04) | 34 | 1.45 | 66 | 3.40 | 122 | 4.93 | 212 | 5.88 | 305 | 5.07 | 321 | 5.82 | 314 | 5.73 | 306 | 5.43 |
MgSO4 | (0.05) | 27 | 1.40 | 59 | 2.89 | 108 | 4.76 | 176 | 5.32 | 264 | 5.73 | 309 | 5.24 | 301 | 5.10 | 296 | 5.08 |
Effect of physical parameters on bacterial growth and protease production in optimized medium containing (gl -1 distilled water): glucose, 10.0; gelatin, 20.0; yeast extract, 5.0 and MgSO 4 .7H 2 O, 0.1 | |||||||||||||||||
Incubation Time (h) | |||||||||||||||||
pH | 12 | 24 | 36 | 48 | 60 | 72 | 84 | 96 | |||||||||
A | B | A | B | A | B | A | B | A | B | A | B | A | B | A | B | ||
7.0 | 00 | 0.63 | 00 | 1.73 | 00 | 2.95 | 00 | 4.38 | 00 | 4.92 | 00 | 4.78 | 00 | 4.64 | 00 | 4.51 | |
7.5 | 00 | 0.69 | 00 | 1.83 | 7 | 3.06 | 19 | 4.57 | 32 | 5.10 | 38 | 4.85 | 35 | 4.69 | 31 | 4.32 | |
8.0 | 12 | 0.93 | 21 | 2.40 | 34 | 3.32 | 48 | 4.87 | 64 | 5.30 | 87 | 5.14 | 81 | 5.02 | 78 | 4.85 | |
8.5 | 30 | 1.18 | 76 | 3.04 | 165 | 4.52 | 213 | 5.77 | 294 | 6.08 | 311 | 5.84 | 308 | 5.61 | 304 | 5.22 | |
9.0 | 41 | 1.20 | 106 | 3.10 | 197 | 4.73 | 304 | 6.07 | 386 | 6.18 | 431 | 6.10 | 428 | 5.83 | 417 | 5.26 | |
9.5 | 5 | 1.08 | 17 | 3.06 | 48 | 4.26 | 92 | 5.17 | 135 | 5.50 | 146 | 5.34 | 143 | 5.21 | 138 | 5.02 | |
10.0 | 00 | 0.25 | 00 | 0.34 | 00 | 0.21 | 00 | 0.19 | 00 | 0.16 | 00 | 0.13 | 00 | 0.12 | 00 | 0.09 | |
Agitation speed (rpm) | |||||||||||||||||
50 | 14 | 0.62 | 26 | 1.44 | 41 | 2.58 | 58 | 3.06 | 81 | 3.30 | 97 | 3.16 | 95 | 3.08 | 93 | 3.01 | |
100 | 27 | 0.93 | 93 | 2.17 | 139 | 3.86 | 187 | 4.23 | 249 | 4.95 | 283 | 4.70 | 279 | 4.40 | 273 | 4.19 | |
150 | 41 | 1.20 | 106 | 3.10 | 197 | 4.73 | 304 | 6.07 | 386 | 6.18 | 431 | 6.10 | 428 | 5.83 | 417 | 5.26 | |
200 | 53 | 1.46 | 127 | 3.81 | 261 | 5.48 | 375 | 6.32 | 514 | 6.21 | 509 | 6.03 | 501 | 5.64 | 492 | 5.17 | |
250 | 46 | 1.30 | 113 | 4.05 | 254 | 5.72 | 368 | 6.29 | 491 | 6.14 | 483 | 5.80 | 476 | 5.64 | 468 | 5.37 | |
Temperature (°C) | |||||||||||||||||
10 | 4 | 0.42 | 10 | 0.79 | 18 | 1.13 | 27 | 1.84 | 32 | 2.26 | 46 | 2.81 | 53 | 2.51 | 51 | 2.42 | |
15 | 13 | 0.61 | 32 | 1.06 | 59 | 1.92 | 104 | 2.68 | 167 | 3.96 | 219 | 3.74 | 217 | 3.58 | 216 | 3.42 | |
20 | 24 | 0.92 | 45 | 1.75 | 112 | 3.87 | 287 | 5.11 | 423 | 4.83 | 421 | 4.70 | 418 | 4.47 | 413 | 4.26 | |
25 | 53 | 1.46 | 127 | 3.81 | 261 | 5.48 | 375 | 6.32 | 514 | 6.21 | 509 | 6.03 | 501 | 5.64 | 492 | 5.17 | |
30 | 31 | 1.14 | 84 | 2.59 | 196 | 4.05 | 308 | 5.40 | 435 | 5.27 | 431 | 5.13 | 427 | 4.86 | 421 | 4.33 | |
35 | 18 | 0.85 | 31 | 1.92 | 58 | 2.73 | 87 | 3.42 | 132 | 3.25 | 132 | 3.14 | 129 | 3.01 | 126 | 2.90 | |
40 | 2 | 0.80 | 3 | 1.43 | 7 | 1.84 | 10 | 2.17 | 12 | 1.94 | 11 | 1.72 | 8 | 1.54 | 6 | 1.24 | |