1
|
Ribeiro GO, Gruninger RJ, Jones DR, Beauchemin KA, Yang WZ, Wang Y, Abbott DW, Tsang A, McAllister TA. Effect of ammonia fiber expansion-treated wheat straw and a recombinant fibrolytic enzyme on rumen microbiota and fermentation parameters, total tract digestibility, and performance of lambs. J Anim Sci 2020; 98:skaa116. [PMID: 32369600 PMCID: PMC7199887 DOI: 10.1093/jas/skaa116] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 04/28/2020] [Indexed: 12/30/2022] Open
Abstract
The objective of this study was to evaluate the effect of ammonia fiber expansion (AFEX)-treated wheat straw pellets and a recombinant fibrolytic enzyme on the rumen microbiome, rumen fermentation parameters, total tract diet digestibility, and performance of lambs. Eight rumen cannulated wethers and 60 lambs (n = 15 per diet, 8 rams and 7 ewes) were used in a replicated 4 × 4 Latin square design digestibility study and a complete randomized growth performance study, respectively. Four treatment diets were arranged in a 2 × 2 factorial structure with AFEX wheat straw (0% or 30% AFEX straw pellets on a dietary DM basis replacing alfalfa hay pellets) and fibrolytic enzyme (with or without XYL10C, a β-1,4-xylanase, from Aspergillus niger) as main factors. Enzyme was applied at 100 mg/kg of diet DM, 22 h before feeding. Rumen bacteria diversity Pielou evenness decreased (P = 0.05) with AFEX compared with the control diet and increased (P < 0.01) with enzyme. Enzyme increased (P ≤ 0.02) the relative abundancies of Prevotellaceae UCG-004, Christensenellaceae R-7 group, Saccharofermentans, and uncultured Kiritimatiellaeota. Total protozoa counts were greater (P ≤ 0.04) in the rumen of lambs fed AFEX compared with control, with enzyme reducing (P ≤ 0.05) protozoa counts for both diets. Digestibility of DM did not differ (P > 0.10) among diets, but digestibility of CP was reduced (P = 0.001), and digestibility of NDF and ADF increased (P < 0.05) as AFEX replaced alfalfa. Compared with control, AFEX promoted greater DMI (P = 0.003) and improved ADG up to 42 d on feed (P = 0.03), but not (P = 0.51) over the full ~94-d experiment. Consequently, overall G:F was reduced (P = 0.04) for AFEX when compared with control (0.188 vs. 0.199), but days on feed were lower (P = 0.04) for AFEX (97 vs. 91 d). Enzyme improved DMI of AFEX up to day 70 (P = 0.01), but did not affect DMI of the control diet. Enzyme addition improved ADG of lambs fed both diets in the first 28 d (P = 0.02), but not over the entire feeding period (P ≥ 10). As a result, G:F was improved with enzyme for the first 28 d (P = 0.04), but not overall (P = 0.45). This study shows that AFEX-treated wheat straw can replace alfalfa hay with no loss in lamb growth performance. Additionally, the enzyme XYL10C altered the rumen microbiome and improved G:F in the first month of the feeding.
Collapse
Affiliation(s)
- Gabriel O Ribeiro
- Department of Animal and Poultry Science, University of Saskatchewan College of Agriculture Bioresources, University of Saskatchewan, Saskatoon, Canada
| | - Robert J Gruninger
- Lethbridge Research and Development Centre, Agriculture and Agri-Food Canada, Lethbridge, Canada
| | - Darryl R Jones
- Lethbridge Research and Development Centre, Agriculture and Agri-Food Canada, Lethbridge, Canada
| | - Karen A Beauchemin
- Lethbridge Research and Development Centre, Agriculture and Agri-Food Canada, Lethbridge, Canada
| | - Wen Zhu Yang
- Lethbridge Research and Development Centre, Agriculture and Agri-Food Canada, Lethbridge, Canada
| | - Yuxi Wang
- Lethbridge Research and Development Centre, Agriculture and Agri-Food Canada, Lethbridge, Canada
| | - D Wade Abbott
- Lethbridge Research and Development Centre, Agriculture and Agri-Food Canada, Lethbridge, Canada
| | - Adrian Tsang
- Centre for Structural and Functional Genomics, Concordia University, Montreal, Canada
| | - Tim A McAllister
- Lethbridge Research and Development Centre, Agriculture and Agri-Food Canada, Lethbridge, Canada
| |
Collapse
|
2
|
Campbell T, Bals B, Teymouri F, Glassbrook J, Nielson C, Videto J, Rinard A, Moore J, Julian A, Bringi V. Scale-up and operation of a pilot-scale ammonia fiber expansion reactor. Biotechnol Bioeng 2019; 117:1241-1246. [PMID: 31840804 DOI: 10.1002/bit.27251] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 12/12/2019] [Accepted: 12/13/2019] [Indexed: 11/10/2022]
Abstract
Pretreatment and densification of agricultural residues at regional depots can simplify feedstock supply logistics for the production of biofuels in commercial biorefineries. We have previously reported the performance of a laboratory-scale (5 L) packed-bed ammonia fiber expansion (AFEX) reactor system, which showed significant promise for biomass pretreatment at distributed depots. In this paper, we describe the performance of a 90-fold larger pilot-scale packed-bed AFEX-reactor system, used to produce over 1,500 batches (~36 tons) of pretreated crop residues over a 5-year period. Virtually all unreacted ammonia was successfully removed from the biomass, and 76% of the ammonia was recycled and reused. Pretreatment performance at pilot scale was comparable to laboratory-scale, averaging 74% glucose and 75% xylose yield in a standard test compared with 71% and 73%, respectively. Other operating and maintenance aspects are also discussed.
Collapse
Affiliation(s)
- Tim Campbell
- Michigan Biotechnology Institute, Lansing, Michigan
| | - Bryan Bals
- Michigan Biotechnology Institute, Lansing, Michigan
| | | | | | | | - Josh Videto
- Michigan Biotechnology Institute, Lansing, Michigan
| | | | | | - Allen Julian
- Michigan Biotechnology Institute, Lansing, Michigan
| | - Venkataraman Bringi
- Department of Chemical Engineering and Material Science, Michigan State University, East Lansing, Michigan
| |
Collapse
|
3
|
Bals B, Teymouri F, Haddad D, Julian WA, Vismeh R, Jones AD, Mor P, Van Soest B, Tyagi A, VandeHaar M, Bringi V. Presence of Acetamide in Milk and Beef from Cattle Consuming AFEX-Treated Crop Residues. J Agric Food Chem 2019; 67:10756-10763. [PMID: 31483626 PMCID: PMC6764021 DOI: 10.1021/acs.jafc.9b04030] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
AFEX treatment of crop residues can greatly increase their nutrient availability for ruminants. This study investigated the concentration of acetamide, an ammoniation byproduct, in AFEX-treated crop residues and in milk and meat from ruminants fed these residues. Acetamide concentrations in four AFEX-treated cereal crop residues were comparable and reproducible (4-7 mg/g dry matter). A transient acetamide peak in milk was detected following introduction of AFEX-treated residues to the diet, but an alternative regimen showed the peak can be effectively mitigated. Milk acetamide concentration following this transition was 6 and 10 ppm for cattle and buffalo, respectively, but also decreased over time for cattle while tending to decrease (p = 0.08) for buffalo. There was no difference in acetamide concentration in the meat of cattle consuming AFEX-treated residues for 160 days compared to controls. Further investigation is necessary to determine the metabolism of acetamide in ruminants and a maximum acceptable daily intake for humans.
Collapse
Affiliation(s)
- Bryan Bals
- Michigan
Biotechnology Institute, Lansing Michigan 48910, United States
- E-mail:
| | - Farzaneh Teymouri
- Michigan
Biotechnology Institute, Lansing Michigan 48910, United States
| | - Diane Haddad
- Michigan
Biotechnology Institute, Lansing Michigan 48910, United States
| | - W. Allen Julian
- Michigan
Biotechnology Institute, Lansing Michigan 48910, United States
| | - Ramin Vismeh
- Michigan
Biotechnology Institute, Lansing Michigan 48910, United States
| | - A. Daniel Jones
- Department of Biochemistry
and Molecular Biology, Deptartment of Animal Science, and Department of
Chemical Engineering and Material Science, Michigan State University, East Lansing Michigan 48823, United States
| | - Preeti Mor
- Dairy
Cattle Nutrition Division, National Dairy
Research Institute, Karnal, Haryana 132001, India
| | - Brandon Van Soest
- Department of Biochemistry
and Molecular Biology, Deptartment of Animal Science, and Department of
Chemical Engineering and Material Science, Michigan State University, East Lansing Michigan 48823, United States
| | - Amrish Tyagi
- Dairy
Cattle Nutrition Division, National Dairy
Research Institute, Karnal, Haryana 132001, India
| | - Michael VandeHaar
- Department of Biochemistry
and Molecular Biology, Deptartment of Animal Science, and Department of
Chemical Engineering and Material Science, Michigan State University, East Lansing Michigan 48823, United States
| | - Venkataraman Bringi
- Department of Biochemistry
and Molecular Biology, Deptartment of Animal Science, and Department of
Chemical Engineering and Material Science, Michigan State University, East Lansing Michigan 48823, United States
| |
Collapse
|
4
|
Saleem AM, Ribeiro GO, Sanderson H, Alipour D, Brand T, Hünerberg M, Yang WZ, Santos LV, McAllister TA. Effect of exogenous fibrolytic enzymes and ammonia fiber expansion on the fermentation of wheat straw in an artificial rumen system (RUSITEC)1. J Anim Sci 2019; 97:3535-3549. [PMID: 31260526 PMCID: PMC6667240 DOI: 10.1093/jas/skz224] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2019] [Accepted: 06/28/2019] [Indexed: 11/14/2022] Open
Abstract
This study investigated the effect of treatment of wheat straw using ammonia fiber expansion (AFEX) and exogenous fibrolytic enzymes (Viscozyme) on fiber digestibility, rumen fermentation, microbial protein synthesis, and microbial populations in an artificial rumen system [Rumen Simulation Technique (RUSITEC)]. Four treatments were assigned to 16 vessels (4 per treatment) in 2 RUSITEC apparatuses in a randomized block design. Treatments were arranged as a 2 × 2 factorial using untreated or AFEX-treated wheat straw with or without exogenous fibrolytic enzymes [0 or 500 μg of protein/g straw dry matter (DM)]. Fibrolytic enzymes were applied to straw, prior to sealing in nylon bags. The concentrate mixture was provided in a separate bag within each fermentation vessel. The RUSITECs were adapted for 8 d and disappearance of DM, neutral detergent fiber (NDF), acid detergent fiber (ADF), and crude protein (CP) was measured after 48 h of incubation. Ammonia fiber expansion increased (P < 0.01) the disappearance of wheat straw DM (69.6 vs. 38.3%), NDF (65.6 vs. 36.8%), ADF (61.4 vs. 36.0%), and CP (68.3 vs. 24.0%). Total dietary DM, organic matter (OM), and NDF disappearance was also increased (P ≤ 0.05) by enzymes. Total microbial protein production was greater (P < 0.01) for AFEX-treated (72.9 mg/d) than untreated straw (63.1 mg/d). Total gas and methane (CH4) production (P < 0.01) were also greater for AFEX-treated wheat straw than untreated straw, with a tendency for total gas to increase (P = 0.06) with enzymes. Ammonia fiber expansion increased (P < 0.01) total volatile fatty acid (VFA) production and the molar proportion of propionate, while it decreased (P < 0.01) acetate and the acetate-to-propionate ratio. The AFEX-treated straw had lower relative quantities of fungi, methanogens, and Fibrobacter succinogenes (P < 0.01) and fewer protozoa (P < 0.01) compared to untreated straw. The pH of fermenters fed AFEX-treated straw was lower (P < 0.01) than those fed untreated straw. Both AFEX (P < 0.01) and enzymes (P = 0.02) decreased xylanase activity. There was an enzyme × straw interaction (P = 0.02) for endoglucanase activity. Enzymes increased endoglucanase activity of AFEX-treated wheat straw, but had no effect on untreated straw. The addition of enzymes lowered the relative abundance of Ruminococcus flavefaciens, but increased F. succinogenes. These results indicate that AFEX increased the ruminal disappearance of wheat straw and improved fermentation and microbial protein synthesis in the RUSITEC.
Collapse
Affiliation(s)
- Atef M Saleem
- Animal and Poultry Production Department, Faculty of Agriculture, South Valley University, Qena, Egypt
- Agriculture and Agri-Food Canada, Lethbridge Research and Development Centre, Lethbridge, AB, Canada
| | - Gabriel O Ribeiro
- Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Haley Sanderson
- Agriculture and Agri-Food Canada, Lethbridge Research and Development Centre, Lethbridge, AB, Canada
| | - Daryoush Alipour
- Department of Animal Science, Faculty of Agriculture, Bu-AliSina University, Hamedan, Iran
| | - Tassilo Brand
- Agriculture and Agri-Food Canada, Lethbridge Research and Development Centre, Lethbridge, AB, Canada
- Department of Animal Sciences, Ruminant Nutrition, University of Göttingen, Göttingen, Germany
| | - Martin Hünerberg
- Department of Animal Sciences, Ruminant Nutrition, University of Göttingen, Göttingen, Germany
| | - Wenzhu Z Yang
- Agriculture and Agri-Food Canada, Lethbridge Research and Development Centre, Lethbridge, AB, Canada
| | - Laize V Santos
- Agriculture and Agri-Food Canada, Lethbridge Research and Development Centre, Lethbridge, AB, Canada
- Department of Agricultural Science, State University of Southwestern of Bahia, Bahia, Brazil
| | - Tim A McAllister
- Agriculture and Agri-Food Canada, Lethbridge Research and Development Centre, Lethbridge, AB, Canada
| |
Collapse
|
5
|
Mokomele T, da Costa Sousa L, Balan V, van Rensburg E, Dale BE, Görgens JF. Incorporating anaerobic co-digestion of steam exploded or ammonia fiber expansion pretreated sugarcane residues with manure into a sugarcane-based bioenergy-livestock nexus. Bioresour Technol 2019; 272:326-336. [PMID: 30384207 DOI: 10.1016/j.biortech.2018.10.049] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 10/19/2018] [Accepted: 10/20/2018] [Indexed: 06/08/2023]
Abstract
The co-digestion of pretreated sugarcane lignocelluloses with dairy cow manure (DCM) as a bioenergy production and waste management strategy, for intensive livestock farms located in sugarcane regions, was investigated. Ammonia fiber expansion (AFEX) increased the nitrogen content and accelerated the biodegradability of sugarcane bagasse (SCB) and cane leaf matter (CLM) through the cleavage of lignin carbohydrate crosslinks, resulting in the highest specific methane yields (292-299 L CH4/kg VSadded), biogas methane content (57-59% v/v) and biodegradation rates, with or without co-digestion with DCM. To obtain comparable methane yields, untreated and steam exploded (StEx) SCB and CLM had to be co-digested with DCM, at mass ratios providing initial C/N ratios in the range of 18 to 35. Co-digestion with DCM improved the nutrient content of the solid digestates, providing digestates that could be used as biofertilizer to replace CLM that is removed from sugarcane fields during green harvesting.
Collapse
Affiliation(s)
- Thapelo Mokomele
- Department of Process Engineering, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa; Biomass Conversion Research Laboratory, Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI, USA.
| | - Leonardo da Costa Sousa
- Biomass Conversion Research Laboratory, Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI, USA; Great Lakes Bioenergy Research Center (GLBRC), Michigan State University, East Lansing, MI, USA.
| | - Venkatesh Balan
- Biomass Conversion Research Laboratory, Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI, USA; Department of Engineering Technology, Biotechnology Division, School of Technology, University of Houston, Houston, TX 77204, USA.
| | - Eugéne van Rensburg
- Department of Process Engineering, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa.
| | - Bruce E Dale
- Biomass Conversion Research Laboratory, Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI, USA; Great Lakes Bioenergy Research Center (GLBRC), Michigan State University, East Lansing, MI, USA.
| | - Johann F Görgens
- Department of Process Engineering, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa.
| |
Collapse
|
6
|
Flores-Gómez CA, Escamilla Silva EM, Zhong C, Dale BE, da Costa Sousa L, Balan V. Conversion of lignocellulosic agave residues into liquid biofuels using an AFEX™-based biorefinery. Biotechnol Biofuels 2018; 11:7. [PMID: 29371883 PMCID: PMC5769373 DOI: 10.1186/s13068-017-0995-6] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 12/08/2017] [Indexed: 05/22/2023]
Abstract
BACKGROUND Agave-based alcoholic beverage companies generate thousands of tons of solid residues per year in Mexico. These agave residues might be used for biofuel production due to their abundance and favorable sustainability characteristics. In this work, agave leaf and bagasse residues from species Agave tequilana and Agave salmiana were subjected to pretreatment using the ammonia fiber expansion (AFEX) process. The pretreatment conditions were optimized using a response surface design methodology. We also identified commercial enzyme mixtures that maximize sugar yields for AFEX-pretreated agave bagasse and leaf matter, at ~ 6% glucan (w/w) loading enzymatic hydrolysis. Finally, the pretreated agave hydrolysates (at a total solids loading of ~ 20%) were used for ethanol fermentation using the glucose- and xylose-consuming strain Saccharomyces cerevisiae 424A (LNH-ST), to determine ethanol yields at industrially relevant conditions. RESULTS Low-severity AFEX pretreatment conditions are required (100-120 °C) to enable efficient enzymatic deconstruction of the agave cell wall. These studies showed that AFEX-pretreated A. tequilana bagasse, A. tequilana leaf fiber, and A. salmiana bagasse gave ~ 85% sugar conversion during enzyme hydrolysis and over 90% metabolic yields of ethanol during fermentation without any washing step or nutrient supplementation. On the other hand, although lignocellulosic A. salmiana leaf gave high sugar conversions, the hydrolysate could not be fermented at high solids loadings, apparently due to the presence of natural inhibitory compounds. CONCLUSIONS These results show that AFEX-pretreated agave residues can be effectively hydrolyzed at high solids loading using an optimized commercial enzyme cocktail (at 25 mg protein/g glucan) producing > 85% sugar conversions and over 40 g/L bioethanol titers. These results show that AFEX technology has considerable potential to convert lignocellulosic agave residues to bio-based fuels and chemicals in a biorefinery.
Collapse
Affiliation(s)
- Carlos A. Flores-Gómez
- Departament of Chemical Engineering, Tecnológico Nacional de México, I. T. Celaya, Av. Tecnológico S/N, 38010 Celaya, Guanajuato Mexico
- Department of Engineering, Tecnológico Nacional de México, I. T. Roque, Km 8 Carretera Celaya-J. Rosas, 38110 Celaya, Guanajuato Mexico
| | - Eleazar M. Escamilla Silva
- Departament of Chemical Engineering, Tecnológico Nacional de México, I. T. Celaya, Av. Tecnológico S/N, 38010 Celaya, Guanajuato Mexico
| | - Cheng Zhong
- Key Lab of Industrial Fermentation Microbiology of Ministry of Education, School of Biotechnology, Tianjin University of Science & Technology, Tianjin, People’s Republic of China
| | - Bruce E. Dale
- Department of Chemical Engineering and Materials Science, Michigan State University, 3815 Technology Boulevard, Lansing, MI 48910 USA
- DOE Great Lakes Bioenergy Center, Michigan State University, East Lansing, MI 48823 USA
| | - Leonardo da Costa Sousa
- Department of Chemical Engineering and Materials Science, Michigan State University, 3815 Technology Boulevard, Lansing, MI 48910 USA
- DOE Great Lakes Bioenergy Center, Michigan State University, East Lansing, MI 48823 USA
| | - Venkatesh Balan
- Department of Chemical Engineering and Materials Science, Michigan State University, 3815 Technology Boulevard, Lansing, MI 48910 USA
- DOE Great Lakes Bioenergy Center, Michigan State University, East Lansing, MI 48823 USA
- Biotechnology Division, Department of Engineering Technology, School of Technology, University of Houston, Houston, TX 77004 USA
| |
Collapse
|
7
|
Jin M, Sarks C, Bals BD, Posawatz N, Gunawan C, Dale BE, Balan V. Toward high solids loading process for lignocellulosic biofuel production at a low cost. Biotechnol Bioeng 2017; 114:980-989. [PMID: 27888662 DOI: 10.1002/bit.26229] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 10/23/2016] [Accepted: 11/20/2016] [Indexed: 11/09/2022]
Abstract
High solids loadings (>18 wt%) in enzymatic hydrolysis and fermentation are desired for lignocellulosic biofuel production at a high titer and low cost. However, sugar conversion and ethanol yield decrease with increasing solids loading. The factor(s) limiting sugar conversion at high solids loading is not clearly understood. In the present study, we investigated the effect of solids loading on simultaneous saccharification and co-fermentation (SSCF) of AFEX™ (ammonia fiber expansion) pretreated corn stover for ethanol production using a xylose fermenting strain Saccharomyces cerevisiae 424A(LNH-ST). Decreased sugar conversion and ethanol yield with increasing solids loading were also observed. End-product (ethanol) was proven to be the major cause of this issue and increased degradation products with increasing solids loading was also a cause. For the first time, we show that with in situ removal of end-product by performing SSCF aerobically, sugar conversion stopped decreasing with increasing solids loading and monomeric sugar conversion reached as high as 93% at a high solids loading of 24.9 wt%. Techno-economic analysis was employed to explore the economic possibilities of cellulosic ethanol production at high solids loadings. The results suggest that low-cost in situ removal of ethanol during SSCF would significantly improve the economics of high solids loading processes. Biotechnol. Bioeng. 2017;114: 980-989. © 2016 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Mingjie Jin
- School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China.,Biomass Conversion Research Laboratory (BCRL), Department of Chemical Engineering and Materials Science, DOE Great Lakes Bioenergy Research Center, Michigan State University, Lansing, Michigan
| | - Cory Sarks
- Biomass Conversion Research Laboratory (BCRL), Department of Chemical Engineering and Materials Science, DOE Great Lakes Bioenergy Research Center, Michigan State University, Lansing, Michigan
| | - Bryan D Bals
- Biomass Conversion Research Laboratory (BCRL), Department of Chemical Engineering and Materials Science, DOE Great Lakes Bioenergy Research Center, Michigan State University, Lansing, Michigan
| | - Nick Posawatz
- Biomass Conversion Research Laboratory (BCRL), Department of Chemical Engineering and Materials Science, DOE Great Lakes Bioenergy Research Center, Michigan State University, Lansing, Michigan
| | - Christa Gunawan
- Biomass Conversion Research Laboratory (BCRL), Department of Chemical Engineering and Materials Science, DOE Great Lakes Bioenergy Research Center, Michigan State University, Lansing, Michigan
| | - Bruce E Dale
- Biomass Conversion Research Laboratory (BCRL), Department of Chemical Engineering and Materials Science, DOE Great Lakes Bioenergy Research Center, Michigan State University, Lansing, Michigan
| | - Venkatesh Balan
- Biomass Conversion Research Laboratory (BCRL), Department of Chemical Engineering and Materials Science, DOE Great Lakes Bioenergy Research Center, Michigan State University, Lansing, Michigan
| |
Collapse
|
8
|
Sarks C, Jin M, Balan V, Dale BE. Fed-batch hydrolysate addition and cell separation by settling in high cell density lignocellulosic ethanol fermentations on AFEX™ corn stover in the Rapid Bioconversion with Integrated recycling Technology process. J Ind Microbiol Biotechnol 2017; 44:1261-1272. [PMID: 28536841 DOI: 10.1007/s10295-017-1949-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2016] [Accepted: 05/04/2017] [Indexed: 11/30/2022]
Abstract
The Rapid Bioconversion with Integrated recycling Technology (RaBIT) process uses enzyme and yeast recycling to improve cellulosic ethanol production economics. The previous versions of the RaBIT process exhibited decreased xylose consumption using cell recycle for a variety of different micro-organisms. Process changes were tested in an attempt to eliminate the xylose consumption decrease. Three different RaBIT process changes were evaluated in this work including (1) shortening the fermentation time, (2) fed-batch hydrolysate addition, and (3) selective cell recycling using a settling method. Shorting the RaBIT fermentation process to 11 h and introducing fed-batch hydrolysate addition eliminated any xylose consumption decrease over ten fermentation cycles; otherwise, decreased xylose consumption was apparent by the third cell recycle event. However, partial removal of yeast cells during recycle was not economical when compared to recycling all yeast cells.
Collapse
Affiliation(s)
- Cory Sarks
- Biomass Conversion Research Laboratory (BCRL), Department of Chemical Engineering and Materials Science, Michigan State University, 3815 Technology Boulevard, Lansing, MI, 48910, USA. .,DOE Great Lakes Bioenergy Research Center (GLBRC), Michigan State University, East Lansing, MI, 48824, USA.
| | - Mingjie Jin
- Biomass Conversion Research Laboratory (BCRL), Department of Chemical Engineering and Materials Science, Michigan State University, 3815 Technology Boulevard, Lansing, MI, 48910, USA. .,DOE Great Lakes Bioenergy Research Center (GLBRC), Michigan State University, East Lansing, MI, 48824, USA.
| | - Venkatesh Balan
- Biomass Conversion Research Laboratory (BCRL), Department of Chemical Engineering and Materials Science, Michigan State University, 3815 Technology Boulevard, Lansing, MI, 48910, USA.,DOE Great Lakes Bioenergy Research Center (GLBRC), Michigan State University, East Lansing, MI, 48824, USA
| | - Bruce E Dale
- Biomass Conversion Research Laboratory (BCRL), Department of Chemical Engineering and Materials Science, Michigan State University, 3815 Technology Boulevard, Lansing, MI, 48910, USA.,DOE Great Lakes Bioenergy Research Center (GLBRC), Michigan State University, East Lansing, MI, 48824, USA
| |
Collapse
|
9
|
Stoklosa RJ, Del Pilar Orjuela A, da Costa Sousa L, Uppugundla N, Williams DL, Dale BE, Hodge DB, Balan V. Techno-economic comparison of centralized versus decentralized biorefineries for two alkaline pretreatment processes. Bioresour Technol 2017; 226:9-17. [PMID: 27951509 DOI: 10.1016/j.biortech.2016.11.092] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Revised: 11/21/2016] [Accepted: 11/22/2016] [Indexed: 06/06/2023]
Abstract
In this work, corn stover subjected to ammonia fiber expansion (AFEX™)1 pretreatment or alkaline pre-extraction followed by hydrogen peroxide post-treatment (AHP pretreatment) were compared for their enzymatic hydrolysis yields over a range of solids loadings, enzymes loadings, and enzyme combinations. Process techno-economic models were compared for cellulosic ethanol production for a biorefinery that handles 2000tons per day of corn stover employing a centralized biorefinery approach with AHP or a de-centralized AFEX pretreatment followed by biomass densification feeding a centralized biorefinery. A techno-economic analysis (TEA) of these scenarios shows that the AFEX process resulted in the highest capital investment but also has the lowest minimum ethanol selling price (MESP) at $2.09/gal, primarily due to good energy integration and an efficient ammonia recovery system. The economics of AHP could be made more competitive if oxidant loadings were reduced and the alkali and sugar losses were also decreased.
Collapse
Affiliation(s)
- Ryan J Stoklosa
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824, USA; Great Lakes Bioenergy Research Center, Michigan State University, USA
| | - Andrea Del Pilar Orjuela
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824, USA
| | - Leonardo da Costa Sousa
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824, USA; Great Lakes Bioenergy Research Center, Michigan State University, USA
| | - Nirmal Uppugundla
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824, USA; Great Lakes Bioenergy Research Center, Michigan State University, USA
| | - Daniel L Williams
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824, USA; Great Lakes Bioenergy Research Center, Michigan State University, USA
| | - Bruce E Dale
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824, USA; Great Lakes Bioenergy Research Center, Michigan State University, USA
| | - David B Hodge
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824, USA; Great Lakes Bioenergy Research Center, Michigan State University, USA; Department of Biosystems and Agricultural Engineering, Michigan State University, East Lansing, MI 48824, USA; Division of Sustainable Process Engineering, Luleå University of Technology, Luleå, Sweden.
| | - Venkatesh Balan
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824, USA; Great Lakes Bioenergy Research Center, Michigan State University, USA
| |
Collapse
|
10
|
Perez-Pimienta JA, Flores-Gómez CA, Ruiz HA, Sathitsuksanoh N, Balan V, da Costa Sousa L, Dale BE, Singh S, Simmons BA. Evaluation of agave bagasse recalcitrance using AFEX™, autohydrolysis, and ionic liquid pretreatments. Bioresour Technol 2016; 211:216-23. [PMID: 27017132 DOI: 10.1016/j.biortech.2016.03.103] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 03/17/2016] [Accepted: 03/19/2016] [Indexed: 05/15/2023]
Abstract
A comparative analysis of the response of agave bagasse (AGB) to pretreatment by ammonia fiber expansion (AFEX™), autohydrolysis (AH) and ionic liquid (IL) was performed using 2D nuclear magnetic resonance (NMR) spectroscopy, wet chemistry, enzymatic saccharification and mass balances. It has been found that AFEX pretreatment preserved all carbohydrates in the biomass, whereas AH removed 62.4% of xylan and IL extracted 25% of lignin into wash streams. Syringyl and guaiacyl lignin ratio of untreated AGB was 4.3, whereas for the pretreated biomass the ratios were 4.2, 5.0 and 4.7 for AFEX, AH and IL, respectively. Using NMR spectra, the intensity of β-aryl ether units in aliphatic, anomeric, and aromatic regions decreased in all three pretreated samples when compared to untreated biomass. Yields of glucose plus xylose in the major hydrolysate stream were 42.5, 39.7 and 26.9kg per 100kg of untreated AGB for AFEX, IL and AH, respectively.
Collapse
Affiliation(s)
| | - Carlos A Flores-Gómez
- Department of Chemical Engineering and Materials Science, DOE Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI, United States
| | - Héctor A Ruiz
- Biorefinery Group, Food Research Department, School of Chemistry, Autonomous University of Coahuila, Saltillo, Coahuila, Mexico
| | - Noppadon Sathitsuksanoh
- Department of Chemical Engineering and Conn Center for Renewable Energy Research, University of Louisville, Louisville, KY, United States; Joint BioEnergy Institute, Physical Biosciences Division, Lawrence Berkeley National Laboratory, Emeryville, CA, United States
| | - Venkatesh Balan
- Department of Chemical Engineering and Materials Science, DOE Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI, United States
| | - Leonardo da Costa Sousa
- Department of Chemical Engineering and Materials Science, DOE Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI, United States
| | - Bruce E Dale
- Department of Chemical Engineering and Materials Science, DOE Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI, United States
| | - Seema Singh
- Joint BioEnergy Institute, Physical Biosciences Division, Lawrence Berkeley National Laboratory, Emeryville, CA, United States; Sandia National Laboratories, Biological and Engineering Sciences Center, Livermore, CA, United States
| | - Blake A Simmons
- Joint BioEnergy Institute, Physical Biosciences Division, Lawrence Berkeley National Laboratory, Emeryville, CA, United States; Sandia National Laboratories, Biological and Engineering Sciences Center, Livermore, CA, United States
| |
Collapse
|
11
|
Pattathil S, Hahn MG, Dale BE, Chundawat SPS. Insights into plant cell wall structure, architecture, and integrity using glycome profiling of native and AFEXTM-pre-treated biomass. J Exp Bot 2015; 66:4279-94. [PMID: 25911738 PMCID: PMC4493783 DOI: 10.1093/jxb/erv107] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Cell walls, which constitute the bulk of plant biomass, vary considerably in their structure, composition, and architecture. Studies on plant cell walls can be conducted on both native and pre-treated plant biomass samples, allowing an enhanced understanding of these structural and compositional variations. Here glycome profiling was employed to determine the relative abundance of matrix polysaccharides in several phylogenetically distinct native and pre-treated plant biomasses. Eight distinct biomass types belonging to four different subgroups (i.e. monocot grasses, woody dicots, herbaceous dicots, and softwoods) were subjected to various regimes of AFEX™ (ammonia fiber expansion) pre-treatment [AFEX is a trademark of MBI, Lansing (http://www.mbi.org]. This approach allowed detailed analysis of close to 200 cell wall glycan epitopes and their relative extractability using a high-throughput platform. In general, irrespective of the phylogenetic origin, AFEX™ pre-treatment appeared to cause loosening and improved accessibility of various xylan epitope subclasses in most plant biomass materials studied. For most biomass types analysed, such loosening was also evident for other major non-cellulosic components including subclasses of pectin and xyloglucan epitopes. The studies also demonstrate that AFEX™ pre-treatment significantly reduced cell wall recalcitrance among diverse phylogenies (except softwoods) by inducing structural modifications to polysaccharides that were not detectable by conventional gross composition analyses. It was found that monitoring changes in cell wall glycan compositions and their relative extractability for untreated and pre-treated plant biomass can provide an improved understanding of variations in structure and composition of plant cell walls and delineate the role(s) of matrix polysaccharides in cell wall recalcitrance.
Collapse
Affiliation(s)
- Sivakumar Pattathil
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Michael G Hahn
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA BioEnergy Science Center, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Bruce E Dale
- DOE Great Lakes Bioenergy Research Center, Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824, USA
| | - Shishir P S Chundawat
- DOE Great Lakes Bioenergy Research Center, Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI 48824, USA Present address: Department of Chemical and Biochemical Engineering, C-150A Engineering Building, Rutgers The State University of New Jersey, Piscataway, NJ 08854, USA
| |
Collapse
|
12
|
Tang X, da Costa Sousa L, Jin M, Chundawat SPS, Chambliss CK, Lau MW, Xiao Z, Dale BE, Balan V. Designer synthetic media for studying microbial-catalyzed biofuel production. Biotechnol Biofuels 2015; 8:1. [PMID: 26339291 PMCID: PMC4311453 DOI: 10.1186/s13068-014-0179-6] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Accepted: 12/04/2014] [Indexed: 05/03/2023]
Abstract
BACKGROUND The fermentation inhibition of yeast or bacteria by lignocellulose-derived degradation products, during hexose/pentose co-fermentation, is a major bottleneck for cost-effective lignocellulosic biorefineries. To engineer microbial strains for improved performance, it is critical to understand the mechanisms of inhibition that affect fermentative organisms in the presence of major components of a lignocellulosic hydrolysate. The development of a synthetic lignocellulosic hydrolysate (SH) media with a composition similar to the actual biomass hydrolysate will be an important advancement to facilitate these studies. In this work, we characterized the nutrients and plant-derived decomposition products present in AFEX™ pretreated corn stover hydrolysate (ACH). The SH was formulated based on the ACH composition and was further used to evaluate the inhibitory effects of various families of decomposition products during Saccharomyces cerevisiae 424A (LNH-ST) fermentation. RESULTS The ACH contained high levels of nitrogenous compounds, notably amides, pyrazines, and imidazoles. In contrast, a relatively low content of furans and aromatic and aliphatic acids were found in the ACH. Though most of the families of decomposition products were inhibitory to xylose fermentation, due to their abundance, the nitrogenous compounds showed the most inhibition. From these compounds, amides (products of the ammonolysis reaction) contributed the most to the reduction of the fermentation performance. However, this result is associated to a concentration effect, as the corresponding carboxylic acids (products of hydrolysis) promoted greater inhibition when present at the same molar concentration as the amides. Due to its complexity, the formulated SH did not perfectly match the fermentation profile of the actual hydrolysate, especially the growth curve. However, the SH formulation was effective for studying the inhibitory effect of various compounds on yeast fermentation. CONCLUSIONS The formulation of SHs is an important advancement for future multi-omics studies and for better understanding the mechanisms of fermentation inhibition in lignocellulosic hydrolysates. The SH formulated in this work was instrumental for defining the most important inhibitors in the ACH. Major AFEX decomposition products are less inhibitory to yeast fermentation than the products of dilute acid or steam explosion pretreatments; thus, ACH is readily fermentable by yeast without any detoxification.
Collapse
Affiliation(s)
- Xiaoyu Tang
- />Biogas Institute of Ministry of Agriculture, Section 4-13 Remin South Road, Chengdu, 610041 P. R. China
| | - Leonardo da Costa Sousa
- />DOE Great Lakes Bioenergy Research Center, Biomass Conversion Research Lab (BCRL), Chemical Engineering and Materials Science, Michigan State University, 3815 Technology Boulevard, Suite 1045, Lansing, 48910 USA
| | - Mingjie Jin
- />DOE Great Lakes Bioenergy Research Center, Biomass Conversion Research Lab (BCRL), Chemical Engineering and Materials Science, Michigan State University, 3815 Technology Boulevard, Suite 1045, Lansing, 48910 USA
| | - Shishir PS Chundawat
- />DOE Great Lakes Bioenergy Research Center, Biomass Conversion Research Lab (BCRL), Chemical Engineering and Materials Science, Michigan State University, 3815 Technology Boulevard, Suite 1045, Lansing, 48910 USA
- />Department of Chemical & Biochemical Engineering, Rutgers, The State University of New Jersey, 98 Brett Road, Room C-150A, Piscataway, NJ 08854 USA
| | | | - Ming W Lau
- />DOE Great Lakes Bioenergy Research Center, Biomass Conversion Research Lab (BCRL), Chemical Engineering and Materials Science, Michigan State University, 3815 Technology Boulevard, Suite 1045, Lansing, 48910 USA
| | - Zeyi Xiao
- />School of Chemical Engineering, Sichuan University, No. 24 South Section 1, Yihuan Road, Chengdu, 610065 P. R. China
| | - Bruce E Dale
- />DOE Great Lakes Bioenergy Research Center, Biomass Conversion Research Lab (BCRL), Chemical Engineering and Materials Science, Michigan State University, 3815 Technology Boulevard, Suite 1045, Lansing, 48910 USA
| | - Venkatesh Balan
- />DOE Great Lakes Bioenergy Research Center, Biomass Conversion Research Lab (BCRL), Chemical Engineering and Materials Science, Michigan State University, 3815 Technology Boulevard, Suite 1045, Lansing, 48910 USA
| |
Collapse
|
13
|
Gupta A, Das SP, Ghosh A, Choudhary R, Das D, Goyal A. Bioethanol production from hemicellulose rich Populus nigra involving recombinant hemicellulases from Clostridium thermocellum. Bioresour Technol 2014; 165:205-13. [PMID: 24767793 DOI: 10.1016/j.biortech.2014.03.132] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Revised: 03/22/2014] [Accepted: 03/24/2014] [Indexed: 05/11/2023]
Abstract
Bioethanol was produced from poplar leafy biomass rich in hemicelluloses content involving recombinant Clostridium thermocellum hemicellulases and pentose sugar utilizing Candida shehatae. FT-IR analysis revealed effective AFEX pretreatment of poplar leaves. Repetitive batch strategy yielded ∼1.5-fold rise in cell biomass and specific activity of both, acetylxylanesterase (Axe) and GH43 hemicellulase. TLC and HPAEC exhibited xylose and arabinose release from hydrolyzed biomass. SSF trial with 1% (wv(-1)) pretreated poplar and mixed enzymes showed ∼1.5-fold higher ethanol titre as compared with SHF. The shake flask SSF with 5% (wv(-1)) pretreated poplar furnished 4.56 and 5.43gL(-1) ethanol with Axe and mixed enzymes, respectively. Whereas, bioreactor scale-up exhibited ∼1.25-fold increase in ethanol titres (5.68, 6.75gL(-1)) as compared with shake flask with an yield of 0.295 (gg(-1)) and 0.351 (gg(-1)), respectively with Axe and mixed enzymes.
Collapse
Affiliation(s)
- Ashutosh Gupta
- Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Saprativ P Das
- Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Arabinda Ghosh
- Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Rajan Choudhary
- Department of Biotechnology, National Institute of Technology Durgapur, Durgapur 713209, West Bengal, India
| | - Debasish Das
- Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Arun Goyal
- Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India.
| |
Collapse
|
14
|
Uppugundla N, da Costa Sousa L, Chundawat SPS, Yu X, Simmons B, Singh S, Gao X, Kumar R, Wyman CE, Dale BE, Balan V. A comparative study of ethanol production using dilute acid, ionic liquid and AFEX™ pretreated corn stover. Biotechnol Biofuels 2014; 7:72. [PMID: 24917886 PMCID: PMC4050221 DOI: 10.1186/1754-6834-7-72] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Accepted: 02/19/2014] [Indexed: 05/18/2023]
Abstract
BACKGROUND In a biorefinery producing cellulosic biofuels, biomass pretreatment will significantly influence the efficacy of enzymatic hydrolysis and microbial fermentation. Comparison of different biomass pretreatment techniques by studying the impact of pretreatment on downstream operations at industrially relevant conditions and performing comprehensive mass balances will help focus attention on necessary process improvements, and thereby help reduce the cost of biofuel production. RESULTS An on-going collaboration between the three US Department of Energy (DOE) funded bioenergy research centers (Great Lakes Bioenergy Research Center (GLBRC), Joint BioEnergy Institute (JBEI) and BioEnergy Science Center (BESC)) has given us a unique opportunity to compare the performance of three pretreatment processes, notably dilute acid (DA), ionic liquid (IL) and ammonia fiber expansion (AFEX(TM)), using the same source of corn stover. Separate hydrolysis and fermentation (SHF) was carried out using various combinations of commercially available enzymes and engineered yeast (Saccharomyces cerevisiae 424A) strain. The optimal commercial enzyme combination (Ctec2: Htec2: Multifect Pectinase, percentage total protein loading basis) was evaluated for each pretreatment with a microplate-based assay using milled pretreated solids at 0.2% glucan loading and 15 mg total protein loading/g of glucan. The best enzyme combinations were 67:33:0 for DA, 39:33:28 for IL and 67:17:17 for AFEX. The amounts of sugar (kg) (glucose: xylose: total gluco- and xylo-oligomers) per 100 kg of untreated corn stover produced after 72 hours of 6% glucan loading enzymatic hydrolysis were: DA (25:2:2), IL (31:15:2) and AFEX (26:13:7). Additionally, the amounts of ethanol (kg) produced per 100 kg of untreated corn stover and the respective ethanol metabolic yield (%) achieved with exogenous nutrient supplemented fermentations were: DA (14.0, 92.0%), IL (21.2, 93.0%) and AFEX (20.5, 95.0%), respectively. The reason for lower ethanol yield for DA is because most of the xylose produced during the pretreatment was removed and not converted to ethanol during fermentation. CONCLUSIONS Compositional analysis of the pretreated biomass solids showed no significant change in composition for AFEX treated corn stover, while about 85% of hemicellulose was solubilized after DA pretreatment, and about 90% of lignin was removed after IL pretreatment. As expected, the optimal commercial enzyme combination was different for the solids prepared by different pretreatment technologies. Due to loss of nutrients during the pretreatment and washing steps, DA and IL pretreated hydrolysates required exogenous nutrient supplementation to ferment glucose and xylose efficiently, while AFEX pretreated hydrolysate did not require nutrient supplementation.
Collapse
Affiliation(s)
- Nirmal Uppugundla
- Department of Chemical Engineering and Materials Science, Department of Energy (DOE) Great Lakes Bioenergy Research Center (GLBRC), Michigan State University, East Lansing, MI 48824, USA
| | - Leonardo da Costa Sousa
- Department of Chemical Engineering and Materials Science, Department of Energy (DOE) Great Lakes Bioenergy Research Center (GLBRC), Michigan State University, East Lansing, MI 48824, USA
| | - Shishir PS Chundawat
- Department of Chemical Engineering and Materials Science, Department of Energy (DOE) Great Lakes Bioenergy Research Center (GLBRC), Michigan State University, East Lansing, MI 48824, USA
- Department of Biochemistry, Department of Energy (DOE) Great Lakes Bioenergy Research Center (GLBRC), University of Wisconsin, Madison, WI 53706, USA
| | - Xiurong Yu
- Jilin TuoPai Agriculture Products Development Ltd, Jilin, China
| | - Blake Simmons
- Deconstruction Division, Joint BioEnergy Institute (JBEI), Emeryville, CA 94608, USA
- Biological and Material Science Center, Sandia National Laboratories, Livermore, CA 94550, USA
| | - Seema Singh
- Deconstruction Division, Joint BioEnergy Institute (JBEI), Emeryville, CA 94608, USA
- Biological and Material Science Center, Sandia National Laboratories, Livermore, CA 94550, USA
| | - Xiadi Gao
- BioEnergy Science Center (BESC), Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
- Department of Chemical and Environmental Engineering, Bourns College of Engineering, University of California Riverside, Riverside, CA 92507, USA
- Center for Environmental Research and Technology (CE-CERT), Bourns College of Engineering, University of California Riverside, 1084 Columbia Avenue, Riverside, CA 92507, USA
| | - Rajeev Kumar
- BioEnergy Science Center (BESC), Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
- Center for Environmental Research and Technology (CE-CERT), Bourns College of Engineering, University of California Riverside, 1084 Columbia Avenue, Riverside, CA 92507, USA
| | - Charles E Wyman
- BioEnergy Science Center (BESC), Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
- Department of Chemical and Environmental Engineering, Bourns College of Engineering, University of California Riverside, Riverside, CA 92507, USA
- Center for Environmental Research and Technology (CE-CERT), Bourns College of Engineering, University of California Riverside, 1084 Columbia Avenue, Riverside, CA 92507, USA
| | - Bruce E Dale
- Department of Chemical Engineering and Materials Science, Department of Energy (DOE) Great Lakes Bioenergy Research Center (GLBRC), Michigan State University, East Lansing, MI 48824, USA
| | - Venkatesh Balan
- Department of Chemical Engineering and Materials Science, Department of Energy (DOE) Great Lakes Bioenergy Research Center (GLBRC), Michigan State University, East Lansing, MI 48824, USA
| |
Collapse
|
15
|
Sarks C, Jin M, Sato TK, Balan V, Dale BE. Studying the rapid bioconversion of lignocellulosic sugars into ethanol using high cell density fermentations with cell recycle. Biotechnol Biofuels 2014; 7:73. [PMID: 24847379 PMCID: PMC4026590 DOI: 10.1186/1754-6834-7-73] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2014] [Accepted: 04/29/2014] [Indexed: 05/18/2023]
Abstract
BACKGROUND The Rapid Bioconversion with Integrated recycle Technology (RaBIT) process reduces capital costs, processing times, and biocatalyst cost for biochemical conversion of cellulosic biomass to biofuels by reducing total bioprocessing time (enzymatic hydrolysis plus fermentation) to 48 h, increasing biofuel productivity (g/L/h) twofold, and recycling biocatalysts (enzymes and microbes) to the next cycle. To achieve these results, RaBIT utilizes 24-h high cell density fermentations along with cell recycling to solve the slow/incomplete xylose fermentation issue, which is critical for lignocellulosic biofuel fermentations. Previous studies utilizing similar fermentation conditions showed a decrease in xylose consumption when recycling cells into the next fermentation cycle. Eliminating this decrease is critical for RaBIT process effectiveness for high cycle counts. RESULTS Nine different engineered microbial strains (including Saccharomyces cerevisiae strains, Scheffersomyces (Pichia) stipitis strains, Zymomonas mobilis 8b, and Escherichia coli KO11) were tested under RaBIT platform fermentations to determine their suitability for this platform. Fermentation conditions were then optimized for S. cerevisiae GLBRCY128. Three different nutrient sources (corn steep liquor, yeast extract, and wheat germ) were evaluated to improve xylose consumption by recycled cells. Capacitance readings were used to accurately measure viable cell mass profiles over five cycles. CONCLUSION The results showed that not all strains are capable of effectively performing the RaBIT process. Acceptable performance is largely correlated to the specific xylose consumption rate. Corn steep liquor was found to reduce the deleterious impacts of cell recycle and improve specific xylose consumption rates. The viable cell mass profiles indicated that reduction in specific xylose consumption rate, not a drop in viable cell mass, was the main cause for decreasing xylose consumption.
Collapse
Affiliation(s)
- Cory Sarks
- Biomass Conversion Research Laboratory (BCRL), Department of Chemical Engineering and Materials Science, Michigan State University, 3815 Technology Boulevard, Lansing, MI 48910, USA
- DOE Great Lakes Bioenergy Research Center (GLBRC), Michigan State University, East Lansing, MI 48824, USA
| | - Mingjie Jin
- Biomass Conversion Research Laboratory (BCRL), Department of Chemical Engineering and Materials Science, Michigan State University, 3815 Technology Boulevard, Lansing, MI 48910, USA
- DOE Great Lakes Bioenergy Research Center (GLBRC), Michigan State University, East Lansing, MI 48824, USA
| | - Trey K Sato
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, 1552 University Avenue, Madison, WI 53726, USA
| | - Venkatesh Balan
- Biomass Conversion Research Laboratory (BCRL), Department of Chemical Engineering and Materials Science, Michigan State University, 3815 Technology Boulevard, Lansing, MI 48910, USA
- DOE Great Lakes Bioenergy Research Center (GLBRC), Michigan State University, East Lansing, MI 48824, USA
| | - Bruce E Dale
- Biomass Conversion Research Laboratory (BCRL), Department of Chemical Engineering and Materials Science, Michigan State University, 3815 Technology Boulevard, Lansing, MI 48910, USA
- DOE Great Lakes Bioenergy Research Center (GLBRC), Michigan State University, East Lansing, MI 48824, USA
| |
Collapse
|
16
|
Humpula JF, Uppugundla N, Vismeh R, Sousa L, Chundawat SPS, Jones AD, Balan V, Dale BE, Cheh AM. Probing the nature of AFEX-pretreated corn stover derived decomposition products that inhibit cellulase activity. Bioresour Technol 2014; 152:38-45. [PMID: 24275024 DOI: 10.1016/j.biortech.2013.10.082] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 10/22/2013] [Accepted: 10/25/2013] [Indexed: 05/18/2023]
Abstract
Sequential fractionation of AFEX-pretreated corn stover extracts was carried out using ultra-centrifugation, ultra-filtration, and solid phase extraction to isolate various classes of pretreatment products to evaluate their inhibitory effect on cellulases. Ultra-centrifugation removed dark brown precipitates that caused no appreciable enzyme inhibition. Ultra-filtration of ultra-centrifuged AFEX-pretreated corn stover extractives using a 10 kDa molecular weight cutoff (MWCO) membrane removed additional high molecular weight components that accounted for 24-28% of the total observed enzyme inhibition while a 3 kDa MWCO membrane removed 60-65%, suggesting significant inhibition is caused by oligomeric materials. Solid phase extraction (SPE) of AFEX-pretreated corn stover extractives after ultra-centrifugation removed 34-43% of the inhibition; ultra-filtration with a 5 kDa membrane removed 44-56% of the inhibition and when this ultra-filtrate was subjected to SPE a total of 69-70% of the inhibition were removed. Mass spectrometry found several phenolic compounds among the hydrophobic inhibition removed by SPE adsorption.
Collapse
Affiliation(s)
- James F Humpula
- Biomass Conversion Research Laboratory, Chemical Engineering and Materials Science, Michigan State University, Lansing, MI 48824, USA; DOE-Great Lakes Bioenergy Research Center (GLBRC), Michigan State University, East Lansing, MI 48824, USA
| | - Nirmal Uppugundla
- Biomass Conversion Research Laboratory, Chemical Engineering and Materials Science, Michigan State University, Lansing, MI 48824, USA; DOE-Great Lakes Bioenergy Research Center (GLBRC), Michigan State University, East Lansing, MI 48824, USA
| | - Ramin Vismeh
- DOE-Great Lakes Bioenergy Research Center (GLBRC), Michigan State University, East Lansing, MI 48824, USA; Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA; Department of Chemistry, Michigan State University, East Lansing, MI 48824, USA
| | - Leonardo Sousa
- Biomass Conversion Research Laboratory, Chemical Engineering and Materials Science, Michigan State University, Lansing, MI 48824, USA; DOE-Great Lakes Bioenergy Research Center (GLBRC), Michigan State University, East Lansing, MI 48824, USA
| | - Shishir P S Chundawat
- Biomass Conversion Research Laboratory, Chemical Engineering and Materials Science, Michigan State University, Lansing, MI 48824, USA; DOE-Great Lakes Bioenergy Research Center (GLBRC), Michigan State University, East Lansing, MI 48824, USA; Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - A Daniel Jones
- DOE-Great Lakes Bioenergy Research Center (GLBRC), Michigan State University, East Lansing, MI 48824, USA; Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA; Department of Chemistry, Michigan State University, East Lansing, MI 48824, USA
| | - Venkatesh Balan
- Biomass Conversion Research Laboratory, Chemical Engineering and Materials Science, Michigan State University, Lansing, MI 48824, USA; DOE-Great Lakes Bioenergy Research Center (GLBRC), Michigan State University, East Lansing, MI 48824, USA
| | - Bruce E Dale
- Biomass Conversion Research Laboratory, Chemical Engineering and Materials Science, Michigan State University, Lansing, MI 48824, USA; DOE-Great Lakes Bioenergy Research Center (GLBRC), Michigan State University, East Lansing, MI 48824, USA
| | - Albert M Cheh
- Department of Environmental Science, American University, Washington, DC 20016, USA.
| |
Collapse
|
17
|
Jin M, Bothfeld W, Austin S, Sato TK, La Reau A, Li H, Foston M, Gunawan C, LeDuc RD, Quensen JF, Mcgee M, Uppugundla N, Higbee A, Ranatunga R, Donald CW, Bone G, Ragauskas AJ, Tiedje JM, Noguera DR, Dale BE, Zhang Y, Balan V. Effect of storage conditions on the stability and fermentability of enzymatic lignocellulosic hydrolysate. Bioresour Technol 2013; 147:212-220. [PMID: 23999256 DOI: 10.1016/j.biortech.2013.08.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2013] [Revised: 08/01/2013] [Accepted: 08/03/2013] [Indexed: 05/21/2023]
Abstract
To minimize the change of lignocellulosic hydrolysate composition during storage, the effects of storage conditions (temperature, pH and time) on the composition and fermentability of hydrolysate prepared from AFEX™ (Ammonia Fiber Expansion - a trademark of MBI, Lansing, MI) pretreated corn stover were investigated. Precipitates formed during hydrolysate storage increased with increasing storage pH and time. The precipitate amount was the least when hydrolysate was stored at 4 °C and pH 4.8, accounting for only 0.02% of the total hydrolysate weight after 3-month storage. No significant changes of NMR (Nuclear Magnetic Resonance) spectra and concentrations of sugars, minerals and heavy metals were observed after storage under this condition. When pH was adjusted higher before fermentation, precipitates also formed, consisting of mostly struvite (MgNH4PO4·6H2O) and brushite (CaHPO4·2H2O). Escherichia coli and Saccharomyces cerevisiae fermentation studies and yeast cell growth assays showed no significant difference in fermentability between fresh hydrolysate and stored hydrolysate.
Collapse
Affiliation(s)
- Mingjie Jin
- Biomass Conversion Research Laboratory (BCRL), Department of Chemical Engineering and Materials Science, Michigan State University, 3900 Collins Road, Lansing, MI 48910, United States; DOE Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824, United States.
| | - William Bothfeld
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, 1552 University Ave., Madison, WI 53706, United States
| | - Samantha Austin
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, 1552 University Ave., Madison, WI 53706, United States; Department of Civil and Environmental Engineering, University of Wisconsin-Madison, Madison, WI 53706, United States
| | - Trey K Sato
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, 1552 University Ave., Madison, WI 53706, United States
| | - Alex La Reau
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, 1552 University Ave., Madison, WI 53706, United States
| | - Haibo Li
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, 1552 University Ave., Madison, WI 53706, United States
| | - Marcus Foston
- DOE BioEnergy Science Center, Washington University in St. Louis, 1 Brookings Drive, St. Louis, MO 63130, United States
| | - Christa Gunawan
- Biomass Conversion Research Laboratory (BCRL), Department of Chemical Engineering and Materials Science, Michigan State University, 3900 Collins Road, Lansing, MI 48910, United States; DOE Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824, United States
| | - Richard D LeDuc
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, 1552 University Ave., Madison, WI 53706, United States
| | - John F Quensen
- Center for Microbial Ecology, Michigan State University, 540 Plant and Soil Science Bldg, East Lansing, MI 48824, United States
| | - Mick Mcgee
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, 1552 University Ave., Madison, WI 53706, United States
| | - Nirmal Uppugundla
- Biomass Conversion Research Laboratory (BCRL), Department of Chemical Engineering and Materials Science, Michigan State University, 3900 Collins Road, Lansing, MI 48910, United States; DOE Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824, United States
| | - Alan Higbee
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, 1552 University Ave., Madison, WI 53706, United States
| | - Ruwan Ranatunga
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, 1552 University Ave., Madison, WI 53706, United States
| | - Charles W Donald
- Biomass Conversion Research Laboratory (BCRL), Department of Chemical Engineering and Materials Science, Michigan State University, 3900 Collins Road, Lansing, MI 48910, United States; DOE Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824, United States
| | - Gwen Bone
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, 1552 University Ave., Madison, WI 53706, United States
| | - Arthur J Ragauskas
- DOE BioEnergy Science Center, Georgia Institute of Technology, 500 10th Street, Atlanta, GA 30332, United States
| | - James M Tiedje
- Center for Microbial Ecology, Michigan State University, 540 Plant and Soil Science Bldg, East Lansing, MI 48824, United States
| | - Daniel R Noguera
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, 1552 University Ave., Madison, WI 53706, United States; Department of Civil and Environmental Engineering, University of Wisconsin-Madison, Madison, WI 53706, United States
| | - Bruce E Dale
- Biomass Conversion Research Laboratory (BCRL), Department of Chemical Engineering and Materials Science, Michigan State University, 3900 Collins Road, Lansing, MI 48910, United States; DOE Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824, United States
| | - Yaoping Zhang
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, 1552 University Ave., Madison, WI 53706, United States.
| | - Venkatesh Balan
- Biomass Conversion Research Laboratory (BCRL), Department of Chemical Engineering and Materials Science, Michigan State University, 3900 Collins Road, Lansing, MI 48910, United States; DOE Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824, United States.
| |
Collapse
|
18
|
Shao Q, Cheng C, Ong RG, Zhu L, Zhao C. Hydrogen peroxide presoaking of bamboo prior to AFEX pretreatment and impact on enzymatic conversion to fermentable sugars. Bioresour Technol 2013; 142:26-31. [PMID: 23732919 DOI: 10.1016/j.biortech.2013.05.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Revised: 05/01/2013] [Accepted: 05/04/2013] [Indexed: 06/02/2023]
Abstract
Bamboo is a fast growing plant found worldwide that has high potential as an energy crop. This project evaluated the effectiveness of AFEX pretreatment for converting moso bamboo (Phyllostachys heterocycla var. pubescens) to fermentable sugars, both with and without pre-soaking in hydrogen peroxide. Pretreatment conditions including temperature, water loading, residence time, ammonia loading, and hydrogen peroxide loadings were varied to maximize hydrolysis yields. The optimal conditions for AFEX were 150°C, 0.8 or 2.0 (w/w) water loading, 10-30 min residence time, and 2.0-5.0 (w/w) ammonia loading. The optimal conditions for H-AFEX were same AFEX conditions with 0.7-1.9 (w/w) 30% (wt) hydrogen peroxide solutions loading. Using 15 FPU/g glucan cellulase and under optimal conditions, AFEX pretreatment achieved a theoretical sugars yield of 64.8-72.7% and addition of hydrogen peroxide presoaking increased the yield to 83.4-92.1%. It is about 5-fold and 7-fold increase in sugars yield for AFEX-treated and H-AFEX-treated bamboo respectively.
Collapse
Affiliation(s)
- Qianjun Shao
- School of Engineering, Zhejiang A&F University, Linan, Zhejiang 311300, China.
| | | | | | | | | |
Collapse
|
19
|
Jin M, Sarks C, Gunawan C, Bice BD, Simonett SP, Avanasi Narasimhan R, Willis LB, Dale BE, Balan V, Sato TK. Phenotypic selection of a wild Saccharomyces cerevisiae strain for simultaneous saccharification and co-fermentation of AFEX™ pretreated corn stover. Biotechnol Biofuels 2013; 6:108. [PMID: 23890073 PMCID: PMC3729497 DOI: 10.1186/1754-6834-6-108] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Accepted: 07/25/2013] [Indexed: 05/09/2023]
Abstract
BACKGROUND Simultaneous saccharification and co-fermentation (SSCF) process involves enzymatic hydrolysis of pretreated lignocellulosic biomass and fermentation of glucose and xylose in one bioreactor. The optimal temperatures for enzymatic hydrolysis are higher than the standard fermentation temperature of ethanologenic Saccharomyces cerevisiae. Moreover, degradation products resulting from biomass pretreatment impair fermentation of sugars, especially xylose, and can synergize with high temperature stress. One approach to resolve both concerns is to utilize a strain background with innate tolerance to both elevated temperatures and degradation products. RESULTS In this study, we screened a panel of 108 wild and domesticated Saccharomyces cerevisiae strains isolated from a wide range of environmental niches. One wild strain was selected based on its growth tolerance to simultaneous elevated temperature and AFEX™ (Ammonia Fiber Expansion) degradation products. After engineering the strain with two copies of the Scheffersomyces stipitis xylose reductase, xylitol dehydrogenase and xylulokinase genes, we compared the ability of this engineered strain to the benchmark 424A(LNH-ST) strain in ethanol production and xylose fermentation in standard lab medium and AFEX pretreated corn stover (ACS) hydrolysates, as well as in SSCF of ACS at different temperatures. In SSCF of 9% (w/w) glucan loading ACS at 35°C, the engineered strain showed higher cell viabilities and produced a similar amount of ethanol (51.3 g/L) compared to the benchmark 424A(LNH-ST) strain. CONCLUSION These results validate our approach in the selection of wild Saccharomyces cerevisiae strains with thermo-tolerance and degradation products tolerance properties for lignocellulosic biofuel production. The wild and domesticated yeast strains phenotyped in this work are publically available for others to use as genetic backgrounds for fermentation of their pretreated biomass at elevated temperatures.
Collapse
Affiliation(s)
- Mingjie Jin
- Biomass Conversion Research Laboratory (BCRL), Department of Chemical Engineering and Materials Science, Michigan State University, 3900 Collins Road, Lansing, MI 48910, USA
- DOE Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824, USA
| | - Cory Sarks
- Biomass Conversion Research Laboratory (BCRL), Department of Chemical Engineering and Materials Science, Michigan State University, 3900 Collins Road, Lansing, MI 48910, USA
- DOE Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824, USA
| | - Christa Gunawan
- Biomass Conversion Research Laboratory (BCRL), Department of Chemical Engineering and Materials Science, Michigan State University, 3900 Collins Road, Lansing, MI 48910, USA
- DOE Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824, USA
| | - Benjamin D Bice
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, 1552 University Ave, Madison, WI 53726, USA
| | - Shane P Simonett
- Department of Bacteriology, University of Wisconsin-Madison, 1550 Linden Dr, Madison, WI 53706, USA
| | - Ragothaman Avanasi Narasimhan
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, 1552 University Ave, Madison, WI 53726, USA
| | - Laura B Willis
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, 1552 University Ave, Madison, WI 53726, USA
- Department of Bacteriology, University of Wisconsin-Madison, 1550 Linden Dr, Madison, WI 53706, USA
- U.S. Department of Agriculture, Forest Products Laboratory, 1 Gifford Pinchot Dr, Madison, WI 53726, USA
| | - Bruce E Dale
- Biomass Conversion Research Laboratory (BCRL), Department of Chemical Engineering and Materials Science, Michigan State University, 3900 Collins Road, Lansing, MI 48910, USA
- DOE Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824, USA
| | - Venkatesh Balan
- Biomass Conversion Research Laboratory (BCRL), Department of Chemical Engineering and Materials Science, Michigan State University, 3900 Collins Road, Lansing, MI 48910, USA
- DOE Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824, USA
| | - Trey K Sato
- DOE Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, 1552 University Ave, Madison, WI 53726, USA
| |
Collapse
|