Rapid Dilute Sulfuric Acid Hydrolysis of Soy Flour to Amino Acids for Microbial Processes and Biorefining
Amino acids have relevance in biorefining as fermentation nutrients but also as valued coproducts obtainable from plant biomass. Soy flour was studied as a representative low-cost protein source requiring hydrolysis to free primary amino acids for utilization. Within the context of biorefining, proc...
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-12-01
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| Series: | Fermentation |
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| Online Access: | https://www.mdpi.com/2311-5637/9/12/1028 |
| _version_ | 1797381140217069568 |
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| author | Patricia J. Slininger Maureen A. Shea-Andersh Bruce S. Dien |
| author_facet | Patricia J. Slininger Maureen A. Shea-Andersh Bruce S. Dien |
| author_sort | Patricia J. Slininger |
| collection | DOAJ |
| description | Amino acids have relevance in biorefining as fermentation nutrients but also as valued coproducts obtainable from plant biomass. Soy flour was studied as a representative low-cost protein source requiring hydrolysis to free primary amino acids for utilization. Within the context of biorefining, process schemes, reactant concentrations, times, and temperatures were varied to explore the efficiency of dilute sulfuric acid hydrolysis of soy flour to release amino acids. Two process strategies were optimized. Either soy flour was co-processed with switchgrass biomass using a dilute-acid pretreatment, or it was hydrolyzed alone with dilute acid. Significant improvement to hydrolysate fermentability was accomplished by adding 2.5–10 g/L soy flour to switchgrass pretreatment with dilute sulfuric acid (0.936% <i>v</i>/<i>v</i>) for 15 min at 160 °C. This practice optimized accumulation of neutral sugars and resulted in a 25% reduction in furfural while boosting xylose 7% and up to doubling primary amino nitrogen (PAN), as compared to no soy flour addition to switchgrass pretreatment. When soy flour was hydrolyzed alone, PAN titers were optimized to 1588 mg N/L (9.9 g amino acids/L) and yield to 0.0529 g PAN/g flour (61% of theoretical) using a 10% (<i>v</i>/<i>v</i>) (1.8 M) sulfuric acid hydrolysis 30 min at 160 °C. |
| first_indexed | 2024-03-08T20:47:05Z |
| format | Article |
| id | doaj.art-b69de832ced649b09106a3b8ff6d72c7 |
| institution | Directory Open Access Journal |
| issn | 2311-5637 |
| language | English |
| last_indexed | 2024-03-08T20:47:05Z |
| publishDate | 2023-12-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Fermentation |
| spelling | doaj.art-b69de832ced649b09106a3b8ff6d72c72023-12-22T14:07:57ZengMDPI AGFermentation2311-56372023-12-01912102810.3390/fermentation9121028Rapid Dilute Sulfuric Acid Hydrolysis of Soy Flour to Amino Acids for Microbial Processes and BiorefiningPatricia J. Slininger0Maureen A. Shea-Andersh1Bruce S. Dien2USDA, Agricultural Research Service, National Center for Agricultural Utilization Research, Bioenergy Research Unit, 1815 N University, Peoria, IL 61604, USAUSDA, Agricultural Research Service, National Center for Agricultural Utilization Research, Bioenergy Research Unit, 1815 N University, Peoria, IL 61604, USAUSDA, Agricultural Research Service, National Center for Agricultural Utilization Research, Bioenergy Research Unit, 1815 N University, Peoria, IL 61604, USAAmino acids have relevance in biorefining as fermentation nutrients but also as valued coproducts obtainable from plant biomass. Soy flour was studied as a representative low-cost protein source requiring hydrolysis to free primary amino acids for utilization. Within the context of biorefining, process schemes, reactant concentrations, times, and temperatures were varied to explore the efficiency of dilute sulfuric acid hydrolysis of soy flour to release amino acids. Two process strategies were optimized. Either soy flour was co-processed with switchgrass biomass using a dilute-acid pretreatment, or it was hydrolyzed alone with dilute acid. Significant improvement to hydrolysate fermentability was accomplished by adding 2.5–10 g/L soy flour to switchgrass pretreatment with dilute sulfuric acid (0.936% <i>v</i>/<i>v</i>) for 15 min at 160 °C. This practice optimized accumulation of neutral sugars and resulted in a 25% reduction in furfural while boosting xylose 7% and up to doubling primary amino nitrogen (PAN), as compared to no soy flour addition to switchgrass pretreatment. When soy flour was hydrolyzed alone, PAN titers were optimized to 1588 mg N/L (9.9 g amino acids/L) and yield to 0.0529 g PAN/g flour (61% of theoretical) using a 10% (<i>v</i>/<i>v</i>) (1.8 M) sulfuric acid hydrolysis 30 min at 160 °C.https://www.mdpi.com/2311-5637/9/12/1028renewablebiofuelslignocelluloseprotein hydrolysisswitchgrassportfolio |
| spellingShingle | Patricia J. Slininger Maureen A. Shea-Andersh Bruce S. Dien Rapid Dilute Sulfuric Acid Hydrolysis of Soy Flour to Amino Acids for Microbial Processes and Biorefining Fermentation renewable biofuels lignocellulose protein hydrolysis switchgrass portfolio |
| title | Rapid Dilute Sulfuric Acid Hydrolysis of Soy Flour to Amino Acids for Microbial Processes and Biorefining |
| title_full | Rapid Dilute Sulfuric Acid Hydrolysis of Soy Flour to Amino Acids for Microbial Processes and Biorefining |
| title_fullStr | Rapid Dilute Sulfuric Acid Hydrolysis of Soy Flour to Amino Acids for Microbial Processes and Biorefining |
| title_full_unstemmed | Rapid Dilute Sulfuric Acid Hydrolysis of Soy Flour to Amino Acids for Microbial Processes and Biorefining |
| title_short | Rapid Dilute Sulfuric Acid Hydrolysis of Soy Flour to Amino Acids for Microbial Processes and Biorefining |
| title_sort | rapid dilute sulfuric acid hydrolysis of soy flour to amino acids for microbial processes and biorefining |
| topic | renewable biofuels lignocellulose protein hydrolysis switchgrass portfolio |
| url | https://www.mdpi.com/2311-5637/9/12/1028 |
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