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Nitrogen source and mineral optimization enhance d-xylose conversion to ethanol by the yeast Pichia stipitis NRRL Y-7124
| Content Provider | Semantic Scholar |
|---|---|
| Author | Slininger, Patricia J. Dien, Bruce S. Gorsich, Steven W. Liu, Z. Lewis |
| Copyright Year | 2006 |
| Abstract | Nutrition-based strategies to optimize xylose to ethanol conversion by Pichia stipitis were identified in growing and stationary-phase cultures provided with a defined medium varied in nitrogen, vitamin, purine/pyrimidine, and mineral content via full or partial factorial designs. It is surprising to note that stationary-phase cultures were unable to ferment xylose (or glucose) to ethanol without the addition of a nitrogen source, such as amino acids. Ethanol accumulation increased with arginine, alanine, aspartic acid, glutamic acid, glycine, histidine, leucine, and tyrosine, but declined with isoleucine. Ethanol production from 150 g/l xylose was maximized (61±9 g/l) by providing C:N in the vicinity of ∼57–126:1 and optimizing the combination of urea and amino acids to supply 40–80 % nitrogen from urea and 60–20 % from amino acids (casamino acids supplemented with tryptophan and cysteine). When either urea or amino acids were used as sole nitrogen source, ethanol accumulation dropped to 11 or 24 g/l, respectively, from the maximum of 46 g/l for the optimal nitrogen combination. The interaction of minerals with amino acids and/or urea was key to optimizing ethanol production by cells in both growing and stationary-phase cultures. In nongrowing cultures supplied with nitrogen as amino acids, ethanol concentration increased from 24 to 54 g/l with the addition of an optimized mineral supplement of Fe, Mn, Mg, Ca, Zn, and others. |
| Starting Page | 1285 |
| Ending Page | 1296 |
| Page Count | 12 |
| File Format | PDF HTM / HTML |
| DOI | 10.1007/s00253-006-0435-1 |
| PubMed reference number | 16676180 |
| Journal | Medline |
| Volume Number | 72 |
| Alternate Webpage(s) | https://naldc.nal.usda.gov/naldc/download.xhtml?content=PDF&id=579 |
| Alternate Webpage(s) | https://doi.org/10.1007/s00253-006-0435-1 |
| Journal | Applied Microbiology and Biotechnology |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
