Birgitte Ahring

Biographical Information

Prof. Ahring works with biomass conversion to biofuels and high-value bioproducts. Her expertise is broad and expands from full biorefinery set-ups for biomass conversion involving pretreatment, biological production and molecular tailoring of new biocatalysts to separation and catalysis of platform molecules into fuels and chemicals. Currently she is involved in production of jet fuels using a new bio-based concept and her research group works all the way from proofs of concept activities in the laboratory to pilot scale testing of new concepts. Her overall philosophy is to make full use of any raw material. Even though agricultural and forestry residues are waste from other primary production schemes, they need to be fully exploited in the biorefinery: Don’t waste waste! Full use of the raw material will further lower the cost of the bio-products produced and make biorefineries economically viable.

Biomass conversion often starts with pretreatment. Together with her partners Prof. Ahring has worked extensively with the wet explosion pretreatment, an efficient thermo-chemicals process, which in contrast to other technologies uses no chemicals from the conversion process. During the last 5 years Prof. Ahring’s team has demonstrated that this technology is superior not only for agricultural residues such as straw, husk, bagasse and empty fruit bunches, but also for pre-treating woody residues (both hard- and softwood). The process has recently been shown to be superior for treatment of forest slash—so-called hog fuel—which until now has no other uses than simple combustion in hog fuel burners. Another recent discovery is the wet explosion process introducing changes to the lignin fraction making of manure fibers allowing for far higher methane yield during anaerobic digestion.

Areas of Expertise

• Biotechnology for tailoring of biocatalyst (microbes) for production of biofuels and bio-products
• Pretreatment of biomass for production of sugars, resins, carbon fibers, food and feed, etc.
• Separation and upgrading into biofuels and biochemicals
• Water reuse and anaerobic digestion of waste and wastewaters

2014/15 Publications (out of 322 with review)

1. V. Rana, A. D. Eckard, B.K. Ahring 2014. “Comparison of SHF and SSF of wet exploded corn stover and loblolly pine using in-house enzymes produced from T. reesei RUT C30 and A. saccharolyticus.” Springerplus. Vol. 3, p 516–522.
2. V. Rana, A. Eckard, P. Teller, and B.K. Ahring 2014. “On-site enzymes produced from Trichoderma reesei RUT C30 and Aspergillus saccharolyticus for hydrolysis of wet exploded corn stover and loblolly pine.” Bioresource Technology. Vol. 154, p 282–289.
3. R. Biswas, H. Uellendahl, and B. K Ahring 2014. “Wet explosion pretreatment of sugarcane bagasse for enhanced enzymatic hydrolysis.” Biomass Bioenergy. Vol. 61, p 104–113.
4. B. G. Garrett, K. Srinivas, and B. K. Ahring 2014. “Design and Optimization of a Semi-Continuous High Pressure Carbon Dioxide Extraction System for Acetic Acid.” J. Supercrit. Fluids. Vol. 95, p 243–251.
5. J.A. Iversen and B.K. Ahring 2014. “Monitoring Lignocellulosic Bioethanol Production Processes using Raman Spectroscopy.” Bioresour. Technol. Vol. 172, p 112–120.
6. J.A. Iversen, R.W. Berg, and B.K. Ahring 2014. “Quantitative Monitoring of Yeast Fermentation using Raman Spectroscopy.” Anal. Bioanal. Chem. Vol. 406 (20), p 4911–4919.
7. A. Boaro, K. Young-Mo, A. E. Konopka, S. J. Callister, B. K. Ahring 2014. “Integrated ‘omics analysis for studying the microbial community response to a pH perturbation of a cellulose-degrading bioreactor culture.” FEMS Microbiol. Ecol. Vol. 90, p 802–815.
8. A. Sørensen, J. J. Andersen, B. K. Ahring, P. J. Teller, M. Lübeck 2014. “Screening of carbon sources for beta-glucosidase production by Aspergillus saccharolyticus.” International Biodeterioration & Biodegradation. Vol. 93, p 78–83.
9. I. Weyda, M. Lübeck, B. K. Ahring, Peter S. Lübeck 2014. “Point mutation of the xylose reductase (XR) gene reduces xylitol accumulation and increases citric acid production in Aspergillus carbonarius.” J. Ind. Microbiol. Biotechnol. Vol. 41 (4), p 733–739.
10. Y. Wei, H. Lei, L. Wang, L. Zhu, X. Zhang, Y. Liu, S. Chen, B. Ahring 2014. “Liquid–Liquid Extraction of Biomass Pyrolysis Bio-oil.” Energy Fuels. Vol. 28 (2), p 1207–1212.
11. J. Xue, N. G Isern, R. J. Ewing, A. V Liyu, J. A Sears, H. Knapp, J. Iversen, D. R. Sisk, B. K. Ahring, P. D. Majors 2014. “New generation NMR bioreactor coupled with high-resolution NMR spectroscopy leads to novel discoveries in Moorella thermoacetica metabolic profiles.” Appl. Microbiol. Biotechnol. Vol. 98 (19), p 8367–8375.
12. M. Kolasa, B. K. Ahring, P. S. Lübeck, M. Lübeck 2014. “Co-cultivation of Trichoderma reesei RutC30 with three black Aspergillus strains facilitates efficient hydrolysis of pretreated wheat straw and shows promises for on-site enzyme production.” Bioresour. Technol. Vol. 169, p 143–148.
13. V. Rana, D. Rana, B. K Ahring 2014. “Process Modeling of Enzymatic Hydrolysis of Wet-Exploded Corn Stover.” Bioenerg. Res. Vol. 7 (1), p 450–459.
14. B. K. Ahring, R. Biswas, A. Ahamed, P. J. Teller, H. Uellendahl 2015. “Making lignin accessible for anaerobic digestion by wet-explosion pretreatment.” Bioresour. Technol. Vol. 175, p 182–188.
15. B. G. Garrett, K. Srinivas, and B. K. Ahring 2015. “Performance and Stability of Amberlite™ IRA-67 Ion Exchange Resin for Product Extraction and pH Control during Homolactic Fermentation of Corn Stover Sugars.” Biochem. Eng. J. Vol 95, p 1–8.
16. M. Sinha, A. Sørensen, A. Ahamed, and B. K. Ahring 2015. “Production of Hydrocarbons by Aspergillus carbonarius ITEM 5010.” Fungal Biol. (Accepted).
17. R. Biswas, H. Uellendahl, and B. K. Ahring 2015. “Wet explosion: A feedstock agnostic pretreatment process for lignocellulosic biorefineries.” Bioenerg. Res. (Accepted).