Use of dry yeast cells as a cheap nitrogen source for lactic acid production by thermophilic Bacillus coagulans WCP10-4
Kim Yng Ooi , Jin Chuan Wu
Front. Chem. Sci. Eng. ›› 2015, Vol. 9 ›› Issue (3) : 381 -385.
Use of dry yeast cells as a cheap nitrogen source for lactic acid production by thermophilic Bacillus coagulans WCP10-4
Dry yeast cells (DYC) were used as a cheap nitrogen source to replace expensive yeast extract (YE) for L-lactic acid production by thermophilic Bacillus coagulans. Cassava starch (200 g·L−1) was converted to L-lactic acid by simultaneous saccharification and fermentation using Bacillus coagulans WCP10-4 at 50 °C in the presence of 20 g·L−1 of DYC, giving 148.1 g·L−1 of L-lactic acid at 27 h with a productivity of 5.5 g·L−1·h−1 and a yield of 92%. In contrast, 154.4 g·L−1 of lactic acid was produced at 24 h with a productivity of 6.4 g·L−1·h−1 and a yield of 96% when equal amount of YE was used under the same conditions. Use of pre-autolyzed DYC at 50 °C for overnight slightly improved the lactic acid titer (154.5 g·L−1) and productivity (7.7 g·L−1·h−1) but gave the same yield (96%).
L-lactic acid / thermophilic strain / Bacillus coagulans / dry yeast cells / autolysis / fermentation
| [1] |
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| [2] |
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| [3] |
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| [4] |
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| [5] |
|
| [6] |
|
| [7] |
|
| [8] |
|
| [9] |
|
| [10] |
|
| [11] |
|
| [12] |
|
| [13] |
|
| [14] |
|
| [15] |
|
| [16] |
|
| [17] |
|
| [18] |
|
| [19] |
|
| [20] |
|
| [21] |
Robbins, |
| [22] |
|
| [23] |
|
| [24] |
|
| [25] |
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Higher Education Press and Springer-Verlag Berlin Heidelberg
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