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Bécsy-Jakab VE, Savoy A, Saulnier BK, Singh SK, Hodge DB. Extraction, recovery, and characterization of lignin from industrial corn stover lignin cake. Bioresour Technol 2024; 399:130610. [PMID: 38508284 DOI: 10.1016/j.biortech.2024.130610] [Citation(s) in RCA: 0] [Impact Index Per Article: 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: 01/23/2024] [Revised: 03/08/2024] [Accepted: 03/17/2024] [Indexed: 03/22/2024]
Abstract
Lignin utilization in value-added co-products is an important component of enabling cellulosic biorefinery economics. However, aqueous dilute acid pretreatments yield lignins with limited applications due to significant modification during pretreatment, low solubility in many solvents, and high content of impurities (ash, insoluble polysaccharides). This work addresses these challenges and investigates the extraction and recovery of lignins from lignin-rich insoluble residue following dilute acid pretreatment and enzymatic hydrolysis of corn stover using three extraction approaches: ethanol organosolv, NaOH, and an ionic liquid. The recovered lignins exhibited recovery yields ranging from 30% for the ionic liquid, 44% for the most severe acid ethanol organosolv condition tested, and up to 86% for the most severe NaOH extraction condition. Finally, the fractional solubilities of different recovered lignins were assessed in a range of solvents and these solubilities were used to estimate distributions of Hildebrand and Hansen solubility parameters using a novel approach.
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Affiliation(s)
- Villő Enikő Bécsy-Jakab
- Department of Chemical & Biological Engineering, Montana State University, Bozeman, Montana 59717, USA
| | - Anthony Savoy
- Department of Chemical & Biological Engineering, Montana State University, Bozeman, Montana 59717, USA
| | - Brian K Saulnier
- Department of Chemical & Biological Engineering, Montana State University, Bozeman, Montana 59717, USA
| | - Sandip K Singh
- Department of Chemical & Biological Engineering, Montana State University, Bozeman, Montana 59717, USA
| | - David B Hodge
- Department of Chemical & Biological Engineering, Montana State University, Bozeman, Montana 59717, USA; Division of Sustainable Process Engineering, Luleå University of Technology, Luleå, Sweden.
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2
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Zhang L, Shao G, Jin Y, Yang N, Xu X. Efficient hemicellulose removal from lignocellulose by induced electric field-aided dilute acid pretreatment. Int J Biol Macromol 2024; 261:129839. [PMID: 38309397 DOI: 10.1016/j.ijbiomac.2024.129839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 12/14/2023] [Revised: 01/19/2024] [Accepted: 01/27/2024] [Indexed: 02/05/2024]
Abstract
This study evaluated the effectiveness of induced electric field (IEF) as a novel electrotechnology to assist dilute acid pretreatment of wheat straw (WS) at atmospheric pressure and low temperature (90 °C). The effects of acid concentration and duration on cellulose recovery, hemicellulose and lignin removal were investigated. Meanwhile, the differences between IEF pretreatment and hydrothermal pretreatment were compared by quantitative and qualitative analysis. The optimal pretreatment condition was acid concentration 1 % with the period of 5 h. Under the parameters, the hemicellulose removal of WS after IEF pretreatment was up to 73.6 %, and the enzymatic efficiency was 55.8 %. In addition, the irregular surface morphology, diminished functional groups associated with hemicellulose, increased specific surface area and pore volume, as well as improved thermal stability of the residual WS support the remarkable effect of IEF pretreatment. The feasibility of IEF pretreatment is might be due to the fact that the magneto-induced electric field promotes ionization of H+ and formation of hydrated hydrogen ions, increasing the acidity of the medium. Secondly, electroporation disrupts the anti-degradation structure of WS and increases the accessibility of cellulose to cellulases. It indicated that IEF is a green and efficient strategy for assisting the separation of hemicellulose from lignocellulose.
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Affiliation(s)
- Lingtao Zhang
- School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Guoqiang Shao
- School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Yamei Jin
- School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Na Yang
- School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China.
| | - Xueming Xu
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China.
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3
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Xu C, Wang Y, Zhang C, Liu J, Fu H, Zhou W, Gong Z. Highly-efficient lipid production from hydrolysate of Radix paeoniae alba residue by oleaginous yeast Cutaneotrichosporon oleaginosum. Bioresour Technol 2024; 391:129990. [PMID: 37931762 DOI: 10.1016/j.biortech.2023.129990] [Citation(s) in RCA: 0] [Impact Index Per Article: 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: 08/15/2023] [Revised: 10/24/2023] [Accepted: 11/03/2023] [Indexed: 11/08/2023]
Abstract
Valorization of herbal extraction residues (HERs) into value-added products is pivotal for the sustainability of Chinese medicine industry. Here, seven different enzymatic hydrolysates of dilute acid pretreated HERs were evaluated for lipid production by Cutaneotrichosporon oleaginosum. Among them, the highest sugar yield via hydrolysis and the maximum lipid production were obtained from Radix paeoniae alba residue (RPAR). More interestingly, high proportion of sugar polymers was disintegrated into fermentable sugars during the pretreatment step, allowing a cheap non-enzymatic route for producing sugars from RPAR. A repeated dilute acid pretreatment gained a high sugar concentration of 241.6 g/L through reusing the pretreatment liquor (PL) for four times. Biomass, lipid concentration, and lipid content achieved 49.5 g/L, 35.7 g/L and 72.2 %, respectively, using fed-batch culture of PL. The biodiesel parameters indicated lipids produced from HERs were suitable for biodiesel production. This study offers a cost-effective way to upgrade the HERs waste into micro-biodiesel.
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Affiliation(s)
- Chen Xu
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Heping Road, Wuhan 430081, People's Republic of China
| | - Yanan Wang
- National Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs, National Resource Center for Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing 100700, People's Republic of China
| | - Chuying Zhang
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Heping Road, Wuhan 430081, People's Republic of China
| | - Junheng Liu
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Heping Road, Wuhan 430081, People's Republic of China
| | - Hanqi Fu
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Heping Road, Wuhan 430081, People's Republic of China
| | - Wenting Zhou
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Heping Road, Wuhan 430081, People's Republic of China
| | - Zhiwei Gong
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, 947 Heping Road, Wuhan 430081, People's Republic of China.
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4
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Xiao MZ, Hong S, Shen X, Du ZY, Yuan TQ. In vivo cadmium-assisted dilute acid pretreatment of the phytoremediation sweet sorghum for enzymatic hydrolysis and cadmium enrichment. Environ Pollut 2023; 324:121372. [PMID: 36858104 DOI: 10.1016/j.envpol.2023.121372] [Citation(s) in RCA: 1] [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: 10/06/2022] [Revised: 01/28/2023] [Accepted: 02/26/2023] [Indexed: 06/18/2023]
Abstract
Phytoremediation with energy crops is considered an integrated technology that provides both environment and energy benefits. Herein, the sweet sorghum cultivated on Cd-contaminated farmland (1.21 mg/kg of Cd in the soil) showed promising phytoremediation potential, and the approach for utilizing sorghum stalks was explored. Sweet sorghum bagasse with Cd contamination was pretreated with dilute acid in order to improve enzymatic saccharification and achieve Cd recovery, resulting in harmless and value-added utilization. After pretreatment, hemicelluloses were dramatically degraded, and the lignocellulosic structures were partially deconstructed with xylan removal up to 98.1%. Under the optimal condition (0.75% H2SO4), the highest total sugar yield was 0.48 g/g of raw bagasse; and nearly 98% of Cd was enriched in the liquid phase. Compared with normal biomass, Cd reduced the biomass recalcitrance and further facilitated the deconstruction of biomass under super dilute acid conditions. This work provided an example for the subsequent valorization of Cd-containing biomass and Cd recovery, which will greatly facilitate the development of phytoremediation of heavy metal contaminated soil.
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Affiliation(s)
- Ming-Zhao Xiao
- Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing, 100083, China
| | - Si Hong
- Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing, 100083, China
| | - Xiaojun Shen
- Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing, 100083, China
| | - Zhi-Yan Du
- Yuan Longping High-tech Agriculture Co., Ltd, Changsha, 410000, China
| | - Tong-Qi Yuan
- Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing, 100083, China.
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5
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Zhao X, Lin W, Zheng Y, Lai C, Yong Q, Huang C. Elucidating the inhibiting mechanism of pseudo-lignin on the enzymatic digestibility of cellulose by surface plasmon resonance. Bioresour Technol 2023; 370:128510. [PMID: 36538959 DOI: 10.1016/j.biortech.2022.128510] [Citation(s) in RCA: 0] [Impact Index Per Article: 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: 11/11/2022] [Revised: 12/15/2022] [Accepted: 12/16/2022] [Indexed: 06/17/2023]
Abstract
To explore the interaction mechanism of pseudo-lignin (PL) with cellulase and its influence on cellulose hydrolysis, different PLs were extracted from pretreated bamboo holocellulose (HC) using different organic solvents. Meanwhile, the real-time interaction of PL and cellulase was analyzed using surface plasmon resonance (SPR). The results showed that the extraction effect of the tetrahydrofuran and 1, 4-dioxane/water solution on PL was more effective than the ethanol/water solution. The inhibition of PL fraction obtained from HC by acid pretreatment with higher temperature showed less effect on Avicel's enzymatic hydrolysis. SPR analysis revealed that PL formed at higher pretreatment temperature had a lower dissociation rate after adsorption with cellulase. Besides, the binding affinity of PL (160 °C) to cellulase was much greater than that of PL obtained from 180 °C, indicating PL extracted at higher temperature treated biomass is more easily dissociated from cellulase after binding.
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Affiliation(s)
- Xiaoxue Zhao
- Co-Innovation Center for Efficient Processing and Utilization of Forest Products, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China
| | - Wenqian Lin
- Co-Innovation Center for Efficient Processing and Utilization of Forest Products, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China
| | - Yayue Zheng
- Co-Innovation Center for Efficient Processing and Utilization of Forest Products, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China
| | - Chenhuan Lai
- Co-Innovation Center for Efficient Processing and Utilization of Forest Products, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China
| | - Qiang Yong
- Co-Innovation Center for Efficient Processing and Utilization of Forest Products, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China
| | - Caoxing Huang
- Co-Innovation Center for Efficient Processing and Utilization of Forest Products, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China.
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6
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Chen SJ, Chen X, Zhu MJ. Xylose recovery and bioethanol production from sugarcane bagasse pretreated by mild two-stage ultrasonic assisted dilute acid. Bioresour Technol 2022; 345:126463. [PMID: 34896260 DOI: 10.1016/j.biortech.2021.126463] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [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: 09/07/2021] [Revised: 11/13/2021] [Accepted: 11/27/2021] [Indexed: 06/14/2023]
Abstract
Pretreatment can improve biomass biodegradability. Here, a novel sugarcane bagasse (SCB) pretreatment process based on two-stage ultrasonic assisted dilute H2SO4 (TUDA) under mild conditions was reported. After optimization, the pretreatment was shown to significantly degrade hemicellulose (92.40%) and remove lignin (57.41%) of SCB, leading to reduction of inhibitors and an ethanol fermentation efficiency of 93.37% by SSCF under cellulase 10 FPU/g SCB and 30% pretreated SCB loading. Physical characterization revealed that two-stage ultrasonic could better disrupt SCB than traditional ultrasonic by amplifying the collapse effect and synergistically promoting lignin removal through dilute H2SO4. Furthermore, xylose was also effectively recovered from pretreatment supernatant by biochar derived from bagasse. This study established a simple and efficient pretreatment process for high value-added recycling of SCB from solid residue to pretreatment liquid.
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Affiliation(s)
- Sheng-Jie Chen
- School of Biology and Biological Engineering, Guangdong Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou Higher Education Mega Center, Panyu, Guangzhou 510006, People's Republic of China
| | - Xiong Chen
- Key Laboratory of Fermentation Engineering (Ministry of Education), Hubei University of Technology, Wuhan 430068, Hubei, People's Republic of China
| | - Ming-Jun Zhu
- School of Biology and Biological Engineering, Guangdong Key Laboratory of Fermentation and Enzyme Engineering, South China University of Technology, Guangzhou Higher Education Mega Center, Panyu, Guangzhou 510006, People's Republic of China; Key Laboratory of Fermentation Engineering (Ministry of Education), Hubei University of Technology, Wuhan 430068, Hubei, People's Republic of China; The Key Laboratory of Biological Resources and Ecology of Pamirs Plateau in Xinjiang Uygur Autonomous Region, The Key Laboratory of Ecology and Biological Resources in Yark and Oasis at Colleges & Universities under the Department of Education of Xinjiang Uygur Autonomous Region, College of Life and Geographic Sciences, Kashi University, Kashi 844006, People's Republic of China.
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7
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Luo H, Gao L, Liu Z, Shi Y, Xie F, Bilal M, Yang R, Taherzadeh MJ. Prediction of phenolic compounds and glucose content from dilute inorganic acid pretreatment of lignocellulosic biomass using artificial neural network modeling. BIORESOUR BIOPROCESS 2021; 8:134. [PMID: 38650283 PMCID: PMC10992208 DOI: 10.1186/s40643-021-00488-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 12/12/2021] [Indexed: 11/10/2022] Open
Abstract
Dilute inorganic acids hydrolysis is one of the most promising pretreatment strategies with high recovery of fermentable sugars and low cost for sustainable production of biofuels and chemicals from lignocellulosic biomass. The diverse phenolics derived from lignin degradation during pretreatment are the main inhibitors for enzymatic hydrolysis and fermentation. However, the content features of derived phenolics and produced glucose under different conditions are still unclear due to the highly non-linear characteristic of biomass pretreatment. Here, an artificial neural network (ANN) model was developed for simultaneous prediction of the derived phenolic contents (CPhe) and glucose yield (CGlc) in corn stover hydrolysate before microbial fermentation by integrating dilute acid pretreatment and enzymatic hydrolysis. Six processing parameters including inorganic acid concentration (CIA), pretreatment temperature (T), residence time (t), solid-to-liquid ratio (RSL), kinds of inorganic acids (kIA), and enzyme loading dosage (E) were used as input variables. The CPhe and CGlc were set as the two output variables. An optimized topology structure of 6-12-2 in the ANN model was determined by comparing root means square errors, which has a better prediction efficiency for CPhe (R2 = 0.904) and CGlc (R2 = 0.906). Additionally, the relative importance of six input variables on CPhe and CGlc was firstly calculated by the Garson equation with net weight matrixes. The results indicated that CIA had strong effects (22%-23%) on CPhe or CGlc, then followed by E and T. In conclusion, the findings provide new insights into the sustainable development and inverse optimization of biorefinery process from ANN modeling perspectives.
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Affiliation(s)
- Hongzhen Luo
- School of Life Science and Food Engineering, Huaiyin Institute of Technology, 1 Meicheng East Road, Huaian, 223003, China.
- Jiangsu Provincial Engineering Laboratory for Biomass Conversion and Process Integration, Huaiyin Institute of Technology, Huaian, 223003, China.
| | - Lei Gao
- School of Life Science and Food Engineering, Huaiyin Institute of Technology, 1 Meicheng East Road, Huaian, 223003, China
| | - Zheng Liu
- School of Life Science and Food Engineering, Huaiyin Institute of Technology, 1 Meicheng East Road, Huaian, 223003, China
| | - Yongjiang Shi
- School of Life Science and Food Engineering, Huaiyin Institute of Technology, 1 Meicheng East Road, Huaian, 223003, China
| | - Fang Xie
- School of Life Science and Food Engineering, Huaiyin Institute of Technology, 1 Meicheng East Road, Huaian, 223003, China
| | - Muhammad Bilal
- School of Life Science and Food Engineering, Huaiyin Institute of Technology, 1 Meicheng East Road, Huaian, 223003, China
| | - Rongling Yang
- School of Life Science and Food Engineering, Huaiyin Institute of Technology, 1 Meicheng East Road, Huaian, 223003, China
- Faculty of Applied Technology, Huaiyin Institute of Technology, Huaian, 223003, China
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8
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Lin W, Yang J, Zheng Y, Huang C, Yong Q. Understanding the effects of different residual lignin fractions in acid-pretreated bamboo residues on its enzymatic digestibility. Biotechnol Biofuels 2021; 14:143. [PMID: 34162425 PMCID: PMC8220694 DOI: 10.1186/s13068-021-01994-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Accepted: 06/12/2021] [Indexed: 05/09/2023]
Abstract
BACKGROUND During the dilute acid pretreatment process, the resulting pseudo-lignin and lignin droplets deposited on the surface of lignocellulose and inhibit the enzymatic digestibility of cellulose in lignocellulose. However, how these lignins interact with cellulase enzymes and then affect enzymatic hydrolysis is still unknown. In this work, different fractions of surface lignin (SL) obtained from dilute acid-pretreated bamboo residues (DAP-BR) were extracted by various organic reagents and the residual lignin in extracted DAP-BR was obtained by the milled wood lignin (MWL) method. All of the lignin fractions obtained from DAP-BR were used to investigate the mechanism for interaction between lignin and cellulase using surface plasmon resonance (SPR) technology to understand how they affect enzymatic hydrolysis RESULTS: The results showed that removing surface lignin significantly decreased the yield for enzymatic hydrolysis DAP-BR from 36.5% to 18.6%. The addition of MWL samples to Avicel inhibited its enzymatic hydrolysis, while different SL samples showed slight increases in enzymatic digestibility. Due to the higher molecular weight and hydrophobicity of MWL samples versus SL samples, a stronger affinity for MWL (KD = 6.8-24.7 nM) was found versus that of SL (KD = 39.4-52.6 nM) by SPR analysis. The affinity constants of all tested lignins exhibited good correlations (r > 0.6) with the effects on enzymatic digestibility of extracted DAP-BR and Avicel. CONCLUSIONS This work revealed that the surface lignin on DAP-BR is necessary for maintaining enzyme digestibility levels, and its removal has a negative impact on substrate digestibility.
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Affiliation(s)
- Wenqian Lin
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China
| | - Jinlai Yang
- China National Bamboo Research Center and Key Laboratory of High Efficient Processing of Bamboo of Zhejiang Province, Hangzhou, 310012, Zhejiang, China
| | - Yayue Zheng
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China
| | - Caoxing Huang
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China.
| | - Qiang Yong
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China
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9
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Camargo Guarnizo AF, Woiciechowski AL, Noseda MD, Zevallos Torres LA, Zandona Filho A, Pereira Ramos L, Letti LAJ, Soccol CR. Pentose-rich hydrolysate from oil palm empty fruit bunches for β-glucan production using Pichia jadinii and Cyberlindnera jadinii. Bioresour Technol 2021; 320:124212. [PMID: 33157450 DOI: 10.1016/j.biortech.2020.124212] [Citation(s) in RCA: 0] [Impact Index Per Article: 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: 06/29/2020] [Revised: 09/28/2020] [Accepted: 09/29/2020] [Indexed: 06/11/2023]
Abstract
Pentose-rich hydrolysate obtained from dilute acid pretreatment of oil palm empty fruit bunches was successfully consumed by pentose-consuming yeasts: Cyberlindnera jadinii (Cj) and Pichia jadinii (Pj). Nitrogen supplementation and no additional detoxification step were required. Pj produced 5.87 g/L of biomass using a C/N ratio of 14 after 120 h of fermentation, with xylose consumption of 71%. Cj produced 10.50 g/L of biomass after 96 h of fermentation with C/N ratio of 11.5, with maximum xylose consumption of 85%. β-glucans, high value-added macromolecules, were further extracted from the yeast biomass, achieving yields of 3.1 and 3.0% from Pj and Cj, respectively. The isolated polysaccharides showed a chemical structure of β-(1,3)-glucan with residues of other molecules. Additionally, β-(1,6) branches seems to have been broken during isolation process. Further studies assessing β-glucans production at industrial scale should be carried out looking for nitrogen sources and optimizing the β-glucan isolation method.
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Affiliation(s)
- Andrés Felipe Camargo Guarnizo
- Bioprocess Engineering and Biotechnology Department, Federal University of Paraná, Brazil, Centro Politécnico, CP 19011, Curitiba, PR 81531-908, Brazil
| | - Adenise Lorenci Woiciechowski
- Bioprocess Engineering and Biotechnology Department, Federal University of Paraná, Brazil, Centro Politécnico, CP 19011, Curitiba, PR 81531-908, Brazil
| | - Miguel Daniel Noseda
- Biochemistry and Molecular Biology Department, Federal University of Paraná, Brazil, Centro Politécnico, CP 19046, Curitiba, PR 81531-980, Brazil
| | - Luis Alberto Zevallos Torres
- Bioprocess Engineering and Biotechnology Department, Federal University of Paraná, Brazil, Centro Politécnico, CP 19011, Curitiba, PR 81531-908, Brazil
| | - Arion Zandona Filho
- Chemistry Department, Federal University of Paraná, Brazil, Centro Politécnico, CP 19011, Curitiba, PR 81531-908, Brazil
| | - Luiz Pereira Ramos
- Chemistry Department, Federal University of Paraná, Brazil, Centro Politécnico, CP 19011, Curitiba, PR 81531-908, Brazil
| | - Luiz Alberto Júnior Letti
- Bioprocess Engineering and Biotechnology Department, Federal University of Paraná, Brazil, Centro Politécnico, CP 19011, Curitiba, PR 81531-908, Brazil
| | - Carlos Ricardo Soccol
- Bioprocess Engineering and Biotechnology Department, Federal University of Paraná, Brazil, Centro Politécnico, CP 19011, Curitiba, PR 81531-908, Brazil.
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10
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Saulnier BK, Phongpreecha T, Singh SK, Hodge DB. Impact of dilute acid pretreatment conditions on p-coumarate removal in diverse maize lines. Bioresour Technol 2020; 314:123750. [PMID: 32622284 DOI: 10.1016/j.biortech.2020.123750] [Citation(s) in RCA: 2] [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: 05/25/2020] [Revised: 06/23/2020] [Accepted: 06/24/2020] [Indexed: 06/11/2023]
Abstract
Prior work has identified that lignins recovered from dilute acid-pretreated corn stover exhibit superior performance in phenol-formaldehyde resins used in wood adhesive applications when compared to diverse process-modified lignins derived from other sources. This improved performance is hypothesized to be due to the higher content of unsubstituted phenolic groups specifically p-coumarate lignin esters. In this work, a diverse set of corn stover samples are employed that exhibit diversity in p-coumarate content and total lignin content to explore the relationship between dilute acid pretreatment conditions, p-coumarate ester hydrolysis, xylan solubilization, and the resulting glucose enzymatic hydrolysis yields. The goal of this study is to identify pretreatment conditions that preserve a significant fraction of the p-coumarate esters while simultaneously achieving high enzymatic hydrolysis yields. Kinetic parameters for p-coumarate ester hydrolysis were quantified and pretreatment-biomass combinations were identified that result in glucose hydrolysis yields of more than 90% while retaining nearly 50 mg p-coumarate/g lignin.
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Affiliation(s)
- Brian K Saulnier
- Department of Chemical & Biological Engineering, Montana State University, Bozeman, MT 59717, United States
| | | | - Sandip K Singh
- Department of Chemical & Biological Engineering, Montana State University, Bozeman, MT 59717, United States
| | - David B Hodge
- Department of Chemical & Biological Engineering, Montana State University, Bozeman, MT 59717, United States; Division of Sustainable Process Engineering, Luleå University of Technology, Luleå 97187, Sweden.
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11
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Tan L, Zhong J, Jin YL, Sun ZY, Tang YQ, Kida K. Production of bioethanol from unwashed-pretreated rapeseed straw at high solid loading. Bioresour Technol 2020; 303:122949. [PMID: 32058907 DOI: 10.1016/j.biortech.2020.122949] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [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: 12/11/2019] [Revised: 01/29/2020] [Accepted: 01/31/2020] [Indexed: 06/10/2023]
Abstract
Reduction in water consumption and increase in ethanol concentration are two main challenges for bioethanol production from lignocellulosic materials. To address the two challenges, the aim of this work was to study the production of bioethanol from unwashed-pretreated rapeseed straw (RS) at high solid loading. RS pretreated with 1% (w w-1) H2SO4 at 160 °C for 10 min resulted in excellent digestibility and fermentability of pretreated RS. The unwashed-pretreated RS was subjected to presaccharification and fed-batch simultaneous saccharification and fermentation (P-FB-SSF) at a final solid loading of 22% (w w-1). Ethanol concentration and ethanol yield of 53.1 g L-1 (equivalent to 4.1% (w w-1) based on fermentation slurry) and 72.4% were obtained, respectively. In total, 92.1 g water g-1 ethanol was consumed, a much smaller amount than that observed with washing after pretreatment or fermentation performed at lower solid loading.
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Affiliation(s)
- Li Tan
- College of Architecture and Environment, Sichuan University, Chengdu 610065, China; CAS Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
| | - Jia Zhong
- College of Architecture and Environment, Sichuan University, Chengdu 610065, China
| | - Yan-Ling Jin
- CAS Key Laboratory of Environmental and Applied Microbiology, Environmental Microbiology Key Laboratory of Sichuan Province, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
| | - Zhao-Yong Sun
- College of Architecture and Environment, Sichuan University, Chengdu 610065, China.
| | - Yue-Qing Tang
- College of Architecture and Environment, Sichuan University, Chengdu 610065, China
| | - Kenji Kida
- College of Architecture and Environment, Sichuan University, Chengdu 610065, China
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Iram A, Cekmecelioglu D, Demirci A. Optimization of dilute sulfuric acid, aqueous ammonia, and steam explosion as the pretreatments steps for distillers' dried grains with solubles as a potential fermentation feedstock. Bioresour Technol 2019; 282:475-481. [PMID: 30897485 DOI: 10.1016/j.biortech.2019.03.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2019] [Revised: 03/03/2019] [Accepted: 03/04/2019] [Indexed: 05/14/2023]
Abstract
Distillers' dried grains with solubles (DDGS) is the by-product of bioethanol production from starch-rich grains through dry-mill fermentation. In this study, dilute sulfuric acid hydrolysis, aqueous ammonia, and steam explosion as the pre-treatment methods were optimized. The central composite response surface methodology (RSM) design was used for optimization of dilute acid pretreatment, aqueous ammonia pretreatment. The steam explosion trials were evaluated. The results show that the dilute acid pretreatment at 121 °C is the most effective way of obtaining simple fermentable sugars (0.382 g/g DDGS). The levels of furfural and HMF was also 5.2 mg/g DDGS) and 1.6 mg/g DDGS, respectively, in the dilute sulfuric acid pretreated DDGS. On the other hand, maximum sugar yield for ammonia pretreatment was 0.129 g/g DDGS and 0.055 g/g DDGS for the steam pretreatment, while no significant amounts of furfural and HMF were observed for these two pretreatment methods.
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Affiliation(s)
- Attia Iram
- Department of Agricultural and Biological Engineering, Pennsylvania State University, University Park, PA 16802, USA
| | - Deniz Cekmecelioglu
- Department of Food Engineering, Middle East Technical University, 06800 Ankara, Turkey
| | - Ali Demirci
- Department of Agricultural and Biological Engineering, Pennsylvania State University, University Park, PA 16802, USA.
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13
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Lai C, Yang B, He J, Huang C, Li X, Song X, Yong Q. Enhanced enzymatic digestibility of mixed wood sawdust by lignin modification with naphthol derivatives during dilute acid pretreatment. Bioresour Technol 2018; 269:18-24. [PMID: 30145521 DOI: 10.1016/j.biortech.2018.08.086] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [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: 06/30/2018] [Revised: 08/19/2018] [Accepted: 08/20/2018] [Indexed: 05/20/2023]
Abstract
Effects of the addition of 2-naphthol and 2-naphthol-7-sulfonate on the dilute acid pretreatment of mixed wood sawdust were investigated, respectively. Compared to 2-naphthol, 2-naphtnol-7-sulfonate was more effective to enhance delignification and facilitate the enzymatic hydrolysis. The 72 h hydrolysis yield was improved by 47.8% for 2-naphthol-7-sulfone, while only 9.1% was observed for 2-naphthol. The surface charges, enzyme adsorption, and cellulose accessibility of dilute acid pretreated substrates with or without naphthol derivatives were examined. The improved enzymatic hydrolysis by adding 2-naphthol-7-sulfonate was ascribed to the higher negative surface charges, the lower enzyme non-productive binding, and the higher cellulose accessibility of pretreated substrates. Additionally, the HSQC NMR and 31P NMR analysis were carried out on both decomposed lignins and residual bulk lignins. It indicated that the addition of the naphthol derivatives during pretreatment could suppress the lignin repolymerization, which further mitigated the inhibition of residual lignins on enzymatic hydrolysis.
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Affiliation(s)
- Chenhuan Lai
- Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing 210037, China; College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China
| | - Bo Yang
- College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China
| | - Juan He
- College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China
| | - Caoxing Huang
- College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China
| | - Xin Li
- College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China
| | - Xiangyang Song
- College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China
| | - Qiang Yong
- Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing 210037, China; College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China.
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14
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Yao L, Yoo CG, Meng X, Li M, Pu Y, Ragauskas AJ, Yang H. A structured understanding of cellobiohydrolase I binding to poplar lignin fractions after dilute acid pretreatment. Biotechnol Biofuels 2018; 11:96. [PMID: 29632555 PMCID: PMC5883885 DOI: 10.1186/s13068-018-1087-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2017] [Accepted: 01/11/2018] [Indexed: 05/24/2023]
Abstract
BACKGROUND Cellulase adsorption to lignin is considered a cost barrier for bioethanol production; however, its detailed association mechanism is still not fully understood. In this study, two natural poplar variants with high and low sugar release performance were selected as the low and high recalcitrant raw materials (named L and H, respectively). Three different lignin fractions were extracted using ethanol, followed by p-dioxane and then cellulase treatment from the dilute acid pretreated poplar solids (fraction 1, 2, and 3, respectively). RESULTS Each lignin fraction had different physicochemical properties. Ethanol-extracted lignin had the lowest weight average molecular weight, while the molecular weights for the other two lignin fractions were similar. 31P NMR analysis revealed that lignin fraction with higher molecular weight contained more aliphatic hydroxyl groups and less phenolic hydroxyl groups. Semi-quantitative analysis by 2D HSQC NMR indicated that the lignin fractions isolated from the natural variants had different contents of syringyl (S), guaiacyl (G) and interunit linkages. Lignin extracted by ethanol contained the largest amount of S units, the smallest amounts of G and p-hydroxybenzoate (PB) subunits, while the contents of these lignin subunits in the other two lignin fractions were similar. The lignin fraction obtained after cellulase treatment was primarily comprised of β-O-4 linkages with small amounts of β-5 and β-β linkages. The binding strength of these three lignin fractions obtained by Langmuir equations were in the order of L1 > L3 > L2 for the low recalcitrance poplar and H1 > H2 > H3 for the high recalcitrance poplar. CONCLUSIONS Overall, adsorption ability of lignin was correlated with the sugar release of poplar. Structural features of lignin were associated with its binding to CBH. For natural poplar variants, lignin fractions with lower molecular weight and polydispersity index (PDI) exhibited more CBH adsorption ability. Lignins with more phenolic hydroxyl groups had higher CBH binding strength. It was also found that lignin fractions with more condensed aromatics adsorbed more CBH likely attributed to stronger hydrophobic interactions.
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Affiliation(s)
- Lan Yao
- School of Pulp & Paper Engineering, Hubei University of Technology, Wuhan, 430068 China
- Hubei Provincial Key Laboratory of Green Materials for Light Industry, Hubei University of Technology, Wuhan, 430068 China
- Department of Chemical and Biomolecular Engineering, The University of Tennessee, Knoxville, TN 37996-2200 USA
| | - Chang Geun Yoo
- Joint Institute for Biological Sciences, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 USA
| | - Xianzhi Meng
- Department of Chemical and Biomolecular Engineering, The University of Tennessee, Knoxville, TN 37996-2200 USA
| | - Mi Li
- Joint Institute for Biological Sciences, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 USA
| | - Yunqiao Pu
- Joint Institute for Biological Sciences, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 USA
| | - Arthur J. Ragauskas
- Joint Institute for Biological Sciences, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 USA
- Department of Chemical and Biomolecular Engineering, The University of Tennessee, Knoxville, TN 37996-2200 USA
- Department of Forestry, Wildlife and Fisheries, Center for Renewable Carbon, Institute of Agriculture, The University of Tennessee, Knoxville, TN 37996-2200 USA
| | - Haitao Yang
- School of Pulp & Paper Engineering, Hubei University of Technology, Wuhan, 430068 China
- Hubei Provincial Key Laboratory of Green Materials for Light Industry, Hubei University of Technology, Wuhan, 430068 China
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15
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Nair RB, Kabir MM, Lennartsson PR, Taherzadeh MJ, Horváth IS. Integrated Process for Ethanol, Biogas, and Edible Filamentous Fungi-Based Animal Feed Production from Dilute Phosphoric Acid-Pretreated Wheat Straw. Appl Biochem Biotechnol 2018; 184:48-62. [PMID: 28597311 PMCID: PMC5756571 DOI: 10.1007/s12010-017-2525-1] [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] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Accepted: 05/25/2017] [Indexed: 12/23/2022]
Abstract
Integration of wheat straw for a biorefinery-based energy generation process by producing ethanol and biogas together with the production of high-protein fungal biomass (suitable for feed application) was the main focus of the present study. An edible ascomycete fungal strain Neurospora intermedia was used for the ethanol fermentation and subsequent biomass production from dilute phosphoric acid (0.7 to 1.2% w/v) pretreated wheat straw. At optimum pretreatment conditions, an ethanol yield of 84 to 90% of the theoretical maximum, based on glucan content of substrate straw, was observed from fungal fermentation post the enzymatic hydrolysis process. The biogas production from the pretreated straw slurry showed an improved methane yield potential up to 162% increase, as compared to that of the untreated straw. Additional biogas production, using the syrup, a waste stream obtained post the ethanol fermentation, resulted in a combined total energy output of 15.8 MJ/kg wheat straw. Moreover, using thin stillage (a waste stream from the first-generation wheat-based ethanol process) as a co-substrate to the biogas process resulted in an additional increase by about 14 to 27% in the total energy output as compared to using only wheat straw-based substrates. ᅟ.
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Affiliation(s)
- Ramkumar B Nair
- Swedish Centre for Resource Recovery, University of Borås, 50190, Borås, SE, Sweden.
| | - Maryam M Kabir
- Swedish Centre for Resource Recovery, University of Borås, 50190, Borås, SE, Sweden
| | - Patrik R Lennartsson
- Swedish Centre for Resource Recovery, University of Borås, 50190, Borås, SE, Sweden
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Plaza PE, Gallego-Morales LJ, Peñuela-Vásquez M, Lucas S, García-Cubero MT, Coca M. Biobutanol production from brewer's spent grain hydrolysates by Clostridium beijerinckii. Bioresour Technol 2017; 244:166-174. [PMID: 28779668 DOI: 10.1016/j.biortech.2017.07.139] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [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: 06/05/2017] [Revised: 07/21/2017] [Accepted: 07/22/2017] [Indexed: 05/27/2023]
Abstract
Brewer's spent grain (BSG) is a promising feedstock for ABE fermentation. Sulfuric acid pretreatment of BSG at pH 1, 121°C and different solid loadings (5-15% w/w) was investigated. Enzymatic hydrolysis and ABE fermentation by Clostridium beijerinckii DSM 6422 of non-washed and washed pretreated BSG were performed to compare monosaccharide release and butanol production. Pretreatment at 15% w/w BSG resulted in higher availability of sugars in both the enzymatic hydrolysates and pretreatment liquid, and overall yields of 75gbutanol/kg BSG and 95gABE/kg BSG were obtained. When the enzymatic hydrolysate from the washed pretreated BSG was fermented, butanol (6.0±0.5g/L) and ABE (7.4±1.0g/L) concentrations were lower compared with 7.5±0.6g/L butanol and 10.0±0.8g/L ABE from a control. The fermentation of the liquid released in the pretreatment at 15% w/w resulted in a butanol production of 6.6±0.8g/L with a total ABE of 8.6±1.3g/L after overliming.
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Affiliation(s)
- Pedro E Plaza
- Departamento de Ingeniería Química y Tecnología del Medio Ambiente, Universidad de Valladolid, c/Dr. Mergelina s/n, 47011 Valladolid, Spain
| | - Luis Javier Gallego-Morales
- Grupo Procesos Químicos Industriales, Facultad de Ingeniería, Universidad de Antioquia U de A, C/ 70 # 52-21, Medellín, Colombia
| | - Mariana Peñuela-Vásquez
- Grupo Bioprocesos, Facultad de Ingeniería, Universidad de Antioquia U de A, C/ 70 # 52-21, Medellín, Colombia
| | - Susana Lucas
- Departamento de Ingeniería Química y Tecnología del Medio Ambiente, Universidad de Valladolid, c/Dr. Mergelina s/n, 47011 Valladolid, Spain
| | - M Teresa García-Cubero
- Departamento de Ingeniería Química y Tecnología del Medio Ambiente, Universidad de Valladolid, c/Dr. Mergelina s/n, 47011 Valladolid, Spain
| | - Mónica Coca
- Departamento de Ingeniería Química y Tecnología del Medio Ambiente, Universidad de Valladolid, c/Dr. Mergelina s/n, 47011 Valladolid, Spain.
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Yao L, Yang H, Yoo CG, Meng X, Li M, Pu Y, Ragauskas AJ, Sykes RW. Adsorption of cellobiohydrolases I onto lignin fractions from dilute acid pretreated Broussonetia papyrifera. Bioresour Technol 2017; 244:957-962. [PMID: 28847086 DOI: 10.1016/j.biortech.2017.08.024] [Citation(s) in RCA: 10] [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] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Revised: 08/04/2017] [Accepted: 08/05/2017] [Indexed: 06/07/2023]
Abstract
Broussonetia papyrifera, known as paper mulberry, is a potential feed stock for bioethanol production because of its cellulose-rich composition. Lignin in dilute acid pretreated Broussonetia papyrifera was fractionated to three different fractions, and their physiochemical properties were determined by FT-IR, GPC and NMR analyses. Different structural characteristics were observed from each lignin fraction. Cellobiohydrolases I (CBH) adsorption to each lignin was understood by the lignin properties. The results showed that aliphatic hydroxyl groups in lignin showed positive correlations with the maximum binding ability of CBH onto lignin samples. Also, the contents of phenolic compounds such as p-hydroxyphenyl benzoate (PB), syringyl (S) and guaiacyl (G) units in the lignin influenced their CBH binding.
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Affiliation(s)
- Lan Yao
- School of Pulp & Paper Engineering, Hubei University of Technology, Wuhan 430068, China; State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China; Department of Chemical and Biomolecular Engineering, The University of Tennessee, Knoxville, TN 37996-2200, USA
| | - Haitao Yang
- School of Pulp & Paper Engineering, Hubei University of Technology, Wuhan 430068, China
| | - Chang Geun Yoo
- Joint Institute for Biological Sciences, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Xianzhi Meng
- Department of Chemical and Biomolecular Engineering, The University of Tennessee, Knoxville, TN 37996-2200, USA
| | - Mi Li
- Joint Institute for Biological Sciences, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Yunqiao Pu
- Joint Institute for Biological Sciences, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Arthur J Ragauskas
- Joint Institute for Biological Sciences, Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA; Department of Chemical and Biomolecular Engineering, The University of Tennessee, Knoxville, TN 37996-2200, USA; Department of Forestry, Wildlife and Fisheries, Center of Renewable Carbon, The University of Tennessee, Institute of Agriculture, Knoxville, TN 37996-2200, USA.
| | - Robert W Sykes
- National Bioenergy Center, National Renewable Energy Laboratory, Golden, CO 80401, USA
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Singh N, Mathur AS, Tuli DK, Gupta RP, Barrow CJ, Puri M. Cellulosic ethanol production via consolidated bioprocessing by a novel thermophilic anaerobic bacterium isolated from a Himalayan hot spring. Biotechnol Biofuels 2017; 10:73. [PMID: 28344648 PMCID: PMC5361838 DOI: 10.1186/s13068-017-0756-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2016] [Accepted: 03/10/2017] [Indexed: 05/07/2023]
Abstract
BACKGROUND Cellulose-degrading thermophilic anaerobic bacterium as a suitable host for consolidated bioprocessing (CBP) has been proposed as an economically suited platform for the production of second-generation biofuels. To recognize the overall objective of CBP, fermentation using co-culture of different cellulolytic and sugar-fermenting thermophilic anaerobic bacteria has been widely studied as an approach to achieving improved ethanol production. We assessed monoculture and co-culture fermentation of novel thermophilic anaerobic bacterium for ethanol production from real substrates under controlled conditions. RESULTS In this study, Clostridium sp. DBT-IOC-C19, a cellulose-degrading thermophilic anaerobic bacterium, was isolated from the cellulolytic enrichment cultures obtained from a Himalayan hot spring. Strain DBT-IOC-C19 exhibited a broad substrate spectrum and presented single-step conversion of various cellulosic and hemicellulosic substrates to ethanol, acetate, and lactate with ethanol being the major fermentation product. Additionally, the effect of varying cellulose concentrations on the fermentation performance of the strain was studied, indicating a maximum cellulose utilization ability of 10 g L-1 cellulose. Avicel degradation kinetics of the strain DBT-IOC-C19 displayed 94.6% degradation at 5 g L-1 and 82.74% degradation at 10 g L-1 avicel concentration within 96 h of fermentation. In a comparative study with Clostridium thermocellum DSM 1313, the ethanol and total product concentrations were higher by the newly isolated strain on pretreated rice straw at an equivalent substrate loading. Three different co-culture combinations were used on various substrates that presented two-fold yield improvement than the monoculture during batch fermentation. CONCLUSIONS This study demonstrated the direct fermentation ability of the novel thermophilic anaerobic bacteria on various cellulosic and hemicellulosic substrates into ethanol without the aid of any exogenous enzymes, representing CBP-based fermentation approach. Here, the broad substrate utilization spectrum of isolated cellulolytic thermophilic anaerobic bacterium was shown to be of potential utility. We demonstrated that the co-culture strategy involving novel strains is efficient in improving ethanol production from real substrate.
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Affiliation(s)
- Nisha Singh
- Bioprocessing Laboratory, Centre for Chemistry and Biotechnology, Deakin University, Waurn Ponds, VIC 3217 Australia
- DBT-IOC Centre for Advance Bioenergy Research, Research & Development Centre, Indian Oil Corporation Limited, Sector-13, Faridabad, 121007 India
| | - Anshu S. Mathur
- DBT-IOC Centre for Advance Bioenergy Research, Research & Development Centre, Indian Oil Corporation Limited, Sector-13, Faridabad, 121007 India
| | - Deepak K. Tuli
- DBT-IOC Centre for Advance Bioenergy Research, Research & Development Centre, Indian Oil Corporation Limited, Sector-13, Faridabad, 121007 India
| | - Ravi. P. Gupta
- DBT-IOC Centre for Advance Bioenergy Research, Research & Development Centre, Indian Oil Corporation Limited, Sector-13, Faridabad, 121007 India
| | - Colin J. Barrow
- Bioprocessing Laboratory, Centre for Chemistry and Biotechnology, Deakin University, Waurn Ponds, VIC 3217 Australia
| | - Munish Puri
- Bioprocessing Laboratory, Centre for Chemistry and Biotechnology, Deakin University, Waurn Ponds, VIC 3217 Australia
- Centre for Marine Bioproducts Development, Medical Biotechnology, Flinders University, Adelaide, Australia
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19
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Sun S, Chen W, Tang J, Wang B, Cao X, Sun S, Sun RC. Synergetic effect of dilute acid and alkali treatments on fractional application of rice straw. Biotechnol Biofuels 2016; 9:217. [PMID: 27777619 PMCID: PMC5069894 DOI: 10.1186/s13068-016-0632-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Accepted: 10/04/2016] [Indexed: 05/24/2023]
Abstract
BACKGROUND The biorefinery based on an effective and economical process is to fractionate the three primary constituents (cellulose, hemicelluloses, and lignin) from lignocellulosic biomass, in which the constituents can be respectively converted into high-value-added products. In this study, a successive treatment with dilute acid (0.25-1.0 % aqueous H2SO4, 100-150 °C, 0.5-3.0 h) and alkali (1.5 % aqueous NaOH, 80 °C, 3 h) was performed to produce xylooligosaccharides (XOS), high-purity lignin, and cellulose-rich substrates to produce glucose for ethanol production from rice straw (RS). RESULTS During the dilute acid pretreatment, the maximum production of XOS (12.8 g XOS/100 g RS) with a relatively low level of byproducts was achieved at a relatively low temperature (130 °C) and a low H2SO4 concentration (0.5 %) for a reaction time of 2.0 h. During the alkali post-treatment, 14.2 g lignin with a higher purity of 99.2 % and 30.3 g glucose with a higher conversion rate by enzymatic hydrolysis were obtained from the successively treated substrates with 100 g RS as starting material. As the pretreatment temperature, H2SO4 concentration, or time increased, more β-O-4 linkages in lignins were cleaved, which resulted in an increase of phenolic OH groups in lignin macromolecules. The signal intensities of G2 and G6 in HSQC spectra gradually reduced and vanished, indicating that a condensation reaction probably occurred at C-2 and C-6 of guaiacyl with the side chains of other lignin. CONCLUSIONS The present study demonstrated that the successive treatments with dilute acid and alkali had a synergetic effect on the fractionation of the three main constituents in RS. It is believed that the results obtained will enhance the availability of the combined techniques in the lignocellulosic biorefinery for the application of the main components, cellulose, hemicelluloses, and lignin as biochemical and biofuels.
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Affiliation(s)
- Shaolong Sun
- Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing, 100083 China
| | - Weijing Chen
- Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing, 100083 China
| | - Jianing Tang
- Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing, 100083 China
| | - Bing Wang
- Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing, 100083 China
| | - Xuefei Cao
- Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing, 100083 China
| | - Shaoni Sun
- Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing, 100083 China
| | - Run-Cang Sun
- Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing, 100083 China
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20
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Kim SM, Dien BS, Tumbleson ME, Rausch KD, Singh V. Improvement of sugar yields from corn stover using sequential hot water pretreatment and disk milling. Bioresour Technol 2016; 216:706-713. [PMID: 27289063 DOI: 10.1016/j.biortech.2016.06.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [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: 03/31/2016] [Revised: 05/31/2016] [Accepted: 06/01/2016] [Indexed: 06/06/2023]
Abstract
Efficient pretreatment is essential for economic conversion of lignocellulosic feedstocks into monosaccharides for biofuel production. To realize high sugar yields with low inhibitor concentrations, hot water or dilute acid pretreatment followed by disk milling is proposed. Corn stover at 20% solids was pretreated with hot water at 160-200°C for 4-8min with and without subsequent milling. Hot water pretreatment and disk milling acted synergistically to improve glucose and xylose yields by 89% and 134%, respectively, compared to hot water pretreatment alone. Hot water pretreated (180°C for 4min) and milled samples had the highest glucose and xylose yields among all hot water pretreated and milled samples, which were comparable to samples pretreated with 0.55% dilute acid at 160°C for 4min. However, samples pretreated with 1% dilute acid at 150°C for 4min and disk milled had the highest observed glucose (87.3%) and xylose yields (83.4%).
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Affiliation(s)
- Sun Min Kim
- Department of Agricultural and Biological Engineering, University of Illinois at Urbana-Champaign, 1304 West Pennsylvania Avenue, Urbana, IL 61801, United States
| | - Bruce S Dien
- Bioenergy Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, USDA, Peoria, IL 61604, United States(1)
| | - M E Tumbleson
- Department of Agricultural and Biological Engineering, University of Illinois at Urbana-Champaign, 1304 West Pennsylvania Avenue, Urbana, IL 61801, United States
| | - Kent D Rausch
- Department of Agricultural and Biological Engineering, University of Illinois at Urbana-Champaign, 1304 West Pennsylvania Avenue, Urbana, IL 61801, United States
| | - Vijay Singh
- Department of Agricultural and Biological Engineering, University of Illinois at Urbana-Champaign, 1304 West Pennsylvania Avenue, Urbana, IL 61801, United States.
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21
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Ji Z, Zhang X, Ling Z, Sun RC, Xu F. Tissue specific response of Miscanthus×giganteus to dilute acid pretreatment for enhancing cellulose digestibility. Carbohydr Polym 2016; 154:247-56. [PMID: 27577916 DOI: 10.1016/j.carbpol.2016.06.086] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [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: 02/28/2016] [Revised: 06/20/2016] [Accepted: 06/20/2016] [Indexed: 10/21/2022]
Abstract
The recalcitrance in grasses varies according to cell type and tissue. In this study, dilute acid pretreatment was performed on Miscanthus×giganteus internodes that include rind and pith regions which showing heterogeneous structural and chemical changes. Pretreatment on pith effectively hydrolyzed 73.33% hemicelluloses and separated cohesive cell walls from the compound middle lamella due to lignin migration. Lignin droplets with an average diameter of 49.5±29.3nm were concurrently coalesced on wall surface, that in turn exposed more microfibrils deep in walls to be enzymatically hydrolyzed reaching 82.55%. By contrast, the rind with a relatively intergrated cell structure was covered by larger lignin droplets (101.2±44.1nm) and filled with inaccessible microfibrils limiting enzymatic sacchrification (31.50%). Taken together, the cellulose digestibility of biomass was not majorly influenced by cellulose crystallinity, while it was strongly correlated with the positive effects of hemicelluloses degradation, lignin redistribution, cellulose exposure and loosening cell wall structure.
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Affiliation(s)
- Zhe Ji
- Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing 100083, China; College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, China
| | - Xun Zhang
- Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing 100083, China
| | - Zhe Ling
- Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing 100083, China
| | - Run-Cang Sun
- Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing 100083, China
| | - Feng Xu
- Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing 100083, China; Shandong Key Laboratory of Pulping and Papermaking Engineering, Qilu University of Technology, Jinan 250353, China.
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Kim SM, Guo J, Kwak S, Jin YS, Lee DK, Singh V. Effects of genetic variation and growing condition of prairie cordgrass on feedstock composition and ethanol yield. Bioresour Technol 2015; 183:70-77. [PMID: 25723129 DOI: 10.1016/j.biortech.2015.02.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [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: 11/13/2014] [Revised: 02/06/2015] [Accepted: 02/07/2015] [Indexed: 06/04/2023]
Abstract
Prairie cordgrass (Spartina pectinata L.) has the potential to be a feedstock for bioethanol. It is native to North America, and has extensive genetic diversity. Eleven natural populations of prairie cordgrass harvested in 2011 and 2012 were studied. Compositions of the samples showed significant differences within the same year, and between the two years. Two highest, one medium and two lowest glucan concentration samples from each year were selected to evaluate ethanol yield after dilute acid pretreatment and simultaneous saccharification and co-fermentation using Saccharomycescerevisiae SR8 that can ferment both glucose and xylose. Up to 88% of theoretical ethanol yields were achieved. Our research demonstrates the potential of prairie cordgrass as a dedicated energy crop with ethanol yields of 205.0-275.6 g/kg biomass and 1748-4368 L/ha, depending on feedstock composition and biomass yield. These ethanol yields are comparable with those of switchgrass, corn stover and bagasse.
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Affiliation(s)
- Sun Min Kim
- Department of Agricultural and Biological Engineering, University of Illinois at Urbana-Champaign, 1304 West Pennsylvania Avenue, Urbana, IL 61801, United States
| | - Jia Guo
- Department of Crop Sciences, University of Illinois at Urbana-Champaign, 1102 South Goodwin Avenue, Urbana, IL 61801, United States
| | - Suryang Kwak
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, 905 South Goodwin Avenue, Urbana, IL 61801, United States
| | - Yong-Su Jin
- Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, 905 South Goodwin Avenue, Urbana, IL 61801, United States; Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 1206 West Gregory Drive, Urbana, IL 61801, United States
| | - D K Lee
- Department of Crop Sciences, University of Illinois at Urbana-Champaign, 1102 South Goodwin Avenue, Urbana, IL 61801, United States
| | - Vijay Singh
- Department of Agricultural and Biological Engineering, University of Illinois at Urbana-Champaign, 1304 West Pennsylvania Avenue, Urbana, IL 61801, United States.
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Xin D, Yang Z, Liu F, Xu X, Zhang J. Comparison of aqueous ammonia and dilute acid pretreatment of bamboo fractions: Structure properties and enzymatic hydrolysis. Bioresour Technol 2015; 175:529-36. [PMID: 25459864 DOI: 10.1016/j.biortech.2014.10.160] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2014] [Revised: 10/29/2014] [Accepted: 10/30/2014] [Indexed: 05/21/2023]
Abstract
The effect of two pretreatments methods, aqueous ammonia (SAA) and dilute acid (DA), on the chemical compositions, cellulose crystallinity, morphologic change, and enzymatic hydrolysis of bamboo fractions (bamboo yellow, timber, green, and knot) was compared. Bamboo fractions with SAA pretreatment had better hydrolysability than those with DA pretreatment. High crystallinity index resulted in low hydrolysis yield in the conversion of SAA pretreated bamboo fractions, not DA pretreated fractions. The increase of cellulase loading had modestly positive effect in the hydrolysis of both SAA and DA pretreated bamboo fractions, while supplement of xylanase significantly increased the hydrolysis of the pretreated bamboo fractions, especially after SAA pretreatment. The results indicated that SAA pretreatment was more effective than DA pretreatment in conversion of bamboo fractions, and supplementation of xylanase was necessary in effective conversion of the SAA pretreated fractions into fermentable sugars.
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Affiliation(s)
- Donglin Xin
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China
| | - Zhong Yang
- Research Institute of Wood Industry, Chinese Academy of Forestry, Beijing 100091, China
| | - Feng Liu
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China
| | - Xueru Xu
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China
| | - Junhua Zhang
- College of Forestry, Northwest A&F University, 3 Taicheng Road, Yangling 712100, China.
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Ji Z, Zhang X, Ling Z, Zhou X, Ramaswamy S, Xu F. Visualization of Miscanthus × giganteus cell wall deconstruction subjected to dilute acid pretreatment for enhanced enzymatic digestibility. Biotechnol Biofuels 2015; 8:103. [PMID: 26213569 PMCID: PMC4513789 DOI: 10.1186/s13068-015-0282-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Accepted: 07/01/2015] [Indexed: 05/19/2023]
Abstract
BACKGROUND The natural recalcitrance of lignocellulosic plant cell walls resulting from complex arrangement and distribution of heterogeneous components impedes deconstruction of such cell walls. Dilute acid pretreatment (DAP) is an attractive method to overcome the recalcitrant barriers for rendering enzymatic conversion of polysaccharides. In this study, the internodes of Miscanthus × giganteus, a model bioenergy crop, were subjected to DAP to yield a range of samples with altered cell wall structure and chemistry. The consequent morphological and compositional changes and their possible impact on saccharification efficiency were comprehensively investigated. The use of a series of microscopic and microspectroscopic techniques including fluorescence microscopy (FM), transmission electron microscopy (TEM) and confocal Raman microscopy (CRM)) enabled correlative cell wall structural and chemical information to be obtained. RESULTS DAP of M. × giganteus resulted in solubilization of arabinoxylan and cross-linking hydroxycinnamic acids in a temperature-dependent manner. The optimized pretreatment (1% H2SO4, 170°C for 30 min) resulted in significant enhancement in the saccharification efficiency (51.20%) of treated samples in 72 h, which amounted to 4.4-fold increase in sugar yield over untreated samples (11.80%). The remarkable improvement could be correlated to a sequence of changes occurring in plant cell walls due to their pretreatment-induced deconstruction, namely, loss in the matrix between neighboring cell walls, selective removal of hemicelluloses, redistribution of phenolic polymers and increased exposure of cellulose. The consequently occurred changes in inner cell wall structure including damaging, increase of porosity and loss of mechanical resistance were also found to enhance enzyme access to cellulose and further sugar yield. CONCLUSIONS DAP is a highly effective process for improving bioconversion of cellulose to glucose by breaking down the rigidity and resistance of cell walls. The combination of the most relevant microscopic and microanalytical techniques employed in this work provided information crucial for evaluating the influence of anatomical and compositional changes on enhanced enzymatic digestibility.
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Affiliation(s)
- Zhe Ji
- />Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing, 100083 China
- />Ministry of Education Key Laboratory of Wooden Material Science and Application, Beijing Forestry University, Tsinghua East Road, Beijing, 100083 China
| | - Xun Zhang
- />Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing, 100083 China
- />Ministry of Education Key Laboratory of Wooden Material Science and Application, Beijing Forestry University, Tsinghua East Road, Beijing, 100083 China
| | - Zhe Ling
- />Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing, 100083 China
- />Ministry of Education Key Laboratory of Wooden Material Science and Application, Beijing Forestry University, Tsinghua East Road, Beijing, 100083 China
| | - Xia Zhou
- />Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing, 100083 China
- />Ministry of Education Key Laboratory of Wooden Material Science and Application, Beijing Forestry University, Tsinghua East Road, Beijing, 100083 China
| | - Shri Ramaswamy
- />Department of Bioproducts and Biosystems Engineering, Kaufert Laboratory, University of Minnesota, Saint Paul, MN 55108 USA
| | - Feng Xu
- />Beijing Key Laboratory of Lignocellulosic Chemistry, Beijing Forestry University, Beijing, 100083 China
- />Ministry of Education Key Laboratory of Wooden Material Science and Application, Beijing Forestry University, Tsinghua East Road, Beijing, 100083 China
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25
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Mafe OA, Davies SM, Hancock J, Du C. Development of an estimation model for the evaluation of the energy requirement of dilute acid pretreatments of biomass. Biomass Bioenergy 2015; 72:28-38. [PMID: 26109752 PMCID: PMC4461158 DOI: 10.1016/j.biombioe.2014.11.024] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Revised: 11/25/2014] [Accepted: 11/29/2014] [Indexed: 05/30/2023]
Abstract
This study aims to develop a mathematical model to evaluate the energy required by pretreatment processes used in the production of second generation ethanol. A dilute acid pretreatment process reported by National Renewable Energy Laboratory (NREL) was selected as an example for the model's development. The energy demand of the pretreatment process was evaluated by considering the change of internal energy of the substances, the reaction energy, the heat lost and the work done to/by the system based on a number of simplifying assumptions. Sensitivity analyses were performed on the solid loading rate, temperature, acid concentration and water evaporation rate. The results from the sensitivity analyses established that the solids loading rate had the most significant impact on the energy demand. The model was then verified with data from the NREL benchmark process. Application of this model on other dilute acid pretreatment processes reported in the literature illustrated that although similar sugar yields were reported by several studies, the energy required by the different pretreatments varied significantly.
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Affiliation(s)
- Oluwakemi A.T. Mafe
- School of Biosciences, Sutton Bonington Campus, University of Nottingham, Loughborough LE12 5RD, United Kingdom
| | - Scott M. Davies
- Briggs of Burton, Briggs House, Derby Street, Burton on Trent, Staffordshire DE14 2LH, United Kingdom
| | - John Hancock
- Briggs of Burton, Briggs House, Derby Street, Burton on Trent, Staffordshire DE14 2LH, United Kingdom
| | - Chenyu Du
- School of Biosciences, Sutton Bonington Campus, University of Nottingham, Loughborough LE12 5RD, United Kingdom
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Raman JK, Gnansounou E. Ethanol and lignin production from Brazilian empty fruit bunch biomass. Bioresour Technol 2014; 172:241-248. [PMID: 25265328 DOI: 10.1016/j.biortech.2014.09.043] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [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: 08/06/2014] [Revised: 09/02/2014] [Accepted: 09/06/2014] [Indexed: 06/03/2023]
Abstract
Brazil Government is promoting palm plantations to use degraded land for biofuels. Palm production is expected to increase 35 per cent in future and there would be profuse biomass available that needs to be handled efficiently. Therefore, in this study the potential of EFB from Brazil as raw material for biorefinery was explored by compositional analysis and pretreatment conditions optimization to produce ethanol and co-products. EFB from Brazil contains significant cellulose, hemicellulose, lignin and low ash content. The optimized dilute sulfuric acid pretreatment conditions for efficient cellulose and hemicellulose separation were 160°C temperature, 1.025% v/v acid concentration, 10.5min and 20% solid loading. Under optimum pretreatment process conditions, low enzyme loading (10FPU, 20IU cellulase and glucosidase enzyme/g glucan) and 15% solid loading, 51.1g ethanol, 344.1g solid residue (65% lignin and 24.87MJ/kg LHV) and 3.7l xylose rich liquid could be produced per kg dry EFB.
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Affiliation(s)
- Jegannathan Kenthorai Raman
- Bioenergy and Energy Planning Research Group (BPE), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
| | - Edgard Gnansounou
- Bioenergy and Energy Planning Research Group (BPE), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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Sun Q, Foston M, Meng X, Sawada D, Pingali SV, O’Neill HM, Li H, Wyman CE, Langan P, Ragauskas AJ, Kumar R. Effect of lignin content on changes occurring in poplar cellulose ultrastructure during dilute acid pretreatment. Biotechnol Biofuels 2014; 7:150. [PMID: 25342973 PMCID: PMC4205766 DOI: 10.1186/s13068-014-0150-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2014] [Accepted: 09/25/2014] [Indexed: 05/02/2023]
Abstract
BACKGROUND Obtaining a better understanding of the complex mechanisms occurring during lignocellulosic deconstruction is critical to the continued growth of renewable biofuel production. A key step in bioethanol production is thermochemical pretreatment to reduce plant cell wall recalcitrance for downstream processes. Previous studies of dilute acid pretreatment (DAP) have shown significant changes in cellulose ultrastructure that occur during pretreatment, but there is still a substantial knowledge gap with respect to the influence of lignin on these cellulose ultrastructural changes. This study was designed to assess how the presence of lignin influences DAP-induced changes in cellulose ultrastructure, which might ultimately have large implications with respect to enzymatic deconstruction efforts. RESULTS Native, untreated hybrid poplar (Populus trichocarpa x Populus deltoids) samples and a partially delignified poplar sample (facilitated by acidic sodium chlorite pulping) were separately pretreated with dilute sulfuric acid (0.10 M) at 160°C for 15 minutes and 35 minutes, respectively . Following extensive characterization, the partially delignified biomass displayed more significant changes in cellulose ultrastructure following DAP than the native untreated biomass. With respect to the native untreated poplar, delignified poplar after DAP (in which approximately 40% lignin removal occurred) experienced: increased cellulose accessibility indicated by increased Simons' stain (orange dye) adsorption from 21.8 to 72.5 mg/g, decreased cellulose weight-average degree of polymerization (DPw) from 3087 to 294 units, and increased cellulose crystallite size from 2.9 to 4.2 nm. These changes following DAP ultimately increased enzymatic sugar yield from 10 to 80%. CONCLUSIONS Overall, the results indicate a strong influence of lignin content on cellulose ultrastructural changes occurring during DAP. With the reduction of lignin content during DAP, the enlargement of cellulose microfibril dimensions and crystallite size becomes more apparent. Further, this enlargement of cellulose microfibril dimensions is attributed to specific processes, including the co-crystallization of crystalline cellulose driven by irreversible inter-chain hydrogen bonding (similar to hornification) and/or cellulose annealing that converts amorphous cellulose to paracrystalline and crystalline cellulose. Essentially, lignin acts as a barrier to prevent cellulose crystallinity increase and cellulose fibril coalescence during DAP.
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Affiliation(s)
- Qining Sun
- />School of Chemistry and Biochemistry, Renewable Bioproducts Institute,
Georgia Institute of Technology, 500 10th Street, N.W. Atlanta, GA 30332-0620 USA
| | - Marcus Foston
- />Department of Energy, Environmental and Chemical
Engineering, Washington University, 1 Brookings Drive, Saint Louis, MO 63130 USA
| | - Xianzhi Meng
- />School of Chemistry and Biochemistry, Renewable Bioproducts Institute,
Georgia Institute of Technology, 500 10th Street, N.W. Atlanta, GA 30332-0620 USA
| | - Daisuke Sawada
- />Center for Structural Molecular Biology and the Biology and Soft Matter
Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 USA
| | - Sai Venkatesh Pingali
- />Center for Structural Molecular Biology and the Biology and Soft Matter
Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 USA
| | - Hugh M O’Neill
- />Center for Structural Molecular Biology and the Biology and Soft Matter
Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 USA
| | - Hongjia Li
- />Center for Environmental Research and Technology
(CE-CERT), Bourns College of Engineering, University of California, 1084 Columbia Avenue, Riverside, CA 92507 USA
| | - Charles E Wyman
- />Center for Environmental Research and Technology
(CE-CERT), Bourns College of Engineering, University of California, 1084 Columbia Avenue, Riverside, CA 92507 USA
- />Department of Chemical and Environmental Engineering, Bourns College of Engineering, University of California, 900 University Avenue, Riverside, CA 92521 USA
- />BioEnergy Science Center (BESC), Oak Ridge National Laboratory (ORNL), Oak Ridge, TN 37831 USA
| | - Paul Langan
- />Center for Structural Molecular Biology and the Biology and Soft Matter
Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 USA
| | - Art J Ragauskas
- />School of Chemistry and Biochemistry, Renewable Bioproducts Institute,
Georgia Institute of Technology, 500 10th Street, N.W. Atlanta, GA 30332-0620 USA
- />BioEnergy Science Center (BESC), Oak Ridge National Laboratory (ORNL), Oak Ridge, TN 37831 USA
- />Department of Chemical and Biomolecular Engineering, Department of
Forestry, Wildlife, and Fisheries, Center for Renewable Carbon, University of Tennessee, Knoxville, TN 37996-2200 USA
| | - Rajeev Kumar
- />Center for Environmental Research and Technology
(CE-CERT), Bourns College of Engineering, University of California, 1084 Columbia Avenue, Riverside, CA 92507 USA
- />BioEnergy Science Center (BESC), Oak Ridge National Laboratory (ORNL), Oak Ridge, TN 37831 USA
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28
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Ibáñez AB, Bauer S. Analytical method for the determination of organic acids in dilute acid pretreated biomass hydrolysate by liquid chromatography-time-of-flight mass spectrometry. Biotechnol Biofuels 2014; 7:145. [PMID: 25320638 PMCID: PMC4197226 DOI: 10.1186/s13068-014-0145-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Accepted: 09/22/2014] [Indexed: 06/04/2023]
Abstract
BACKGROUND For the development of lignocellulosic biofuels a common strategy to release hemicellulosic sugars and enhance the enzymatic digestibility of cellulose is the heat pretreatment of biomass with dilute acid. During this process, fermentation inhibitors such as 5-hydroxymethylfurfural, furfural, phenolics, and organic acids are formed and released into the so-called hydrolysate. The phenolic inhibitors have been studied fairly extensively, but fewer studies have focused on the analysis of the organic acids profile. For this purpose, a simple and fast liquid chromatography/mass spectrometry (LC/MS) method for the analysis of organic acids in the hydrolysate has been developed using an ion exchange column based on a polystyrene-divinylbenzene polymer frequently used in biofuel research. The application of the LC/MS method to a hydrolysate from Miscanthus has been evaluated. RESULTS The presented LC/MS method involving only simple sample preparation (filtration and dilution) and external calibration for the analysis of 24 organic acids present in dilute acid pretreated biomass hydrolysate is fast (12 min) and reasonably sensitive despite the small injection volume of 2 μL used. The lower limit of quantification ranged from 0.2 μg/mL to 2.9 μg/mL and the limit of detection from 0.03 μg/mL to 0.7 μg/mL. Analyte recoveries obtained from a spiked hydrolysate were in the range of 70 to 130% of the theoretical yield, except for glyoxylic acid, malic acid, and malonic acid, which showed a higher response due to signal enhancement. Relative standard deviations for the organic acids ranged from 0.4 to 9.2% (average 3.6%) for the intra-day experiment and from 2.1 to 22.8% (average 8.9%) for the inter-day (three-day) experiment. CONCLUSION We have shown that the analysis of the profile of 24 organic acids present in biomass hydrolysate can be achieved by a simple LC/MS method applying external calibration and minimal sample preparation. The organic acids eluted within only 12 min by isocratic elution, enabling high sample throughput. Repeatability (precision and accuracy) and recovery were sufficiently accurate for most of the organic acids tested, making the method suitable for their fast determination in hydrolysate. We envision that this method can be further expanded to a larger number of organic acids, including phenolic acids such as p-coumaric acid and ferulic acid and other molecules depending on the researchers' needs.
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Affiliation(s)
- Ana B Ibáñez
- Energy Biosciences Institute, University of California, Berkeley, CA 94720 USA
| | - Stefan Bauer
- Energy Biosciences Institute, University of California, Berkeley, CA 94720 USA
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Brethauer S, Studer MH, Wyman CE. Application of a slurry feeder to 1 and 3 stage continuous simultaneous saccharification and fermentation of dilute acid pretreated corn stover. Bioresour Technol 2014; 170:470-476. [PMID: 25164339 DOI: 10.1016/j.biortech.2014.07.049] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [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: 05/05/2014] [Revised: 07/11/2014] [Accepted: 07/12/2014] [Indexed: 06/03/2023]
Abstract
Continuous operation is often chosen for conceptual designs of biological processing of cellulosic biomass to ethanol to achieve higher volumetric productivities. Furthermore, continuous stirred tank reactors (CSTR) can handle higher solids concentrations than possible in batch mode due to broth thinning at partial conversion in a continuous fermentor. However, experience and literature data are very limited for continuous simultaneous saccharification and fermentation (cSSF) processes. In this work, a slurry feed system was developed and applied to a 3-stage bench-scale cSSF train to convert pretreated corn stover to ethanol and determine the effects of dilution rate and number of fermentation vessels on overall volumetric productivity. The highest productivity of 0.4gL(-1)h(-1) was achieved in a single cSSF vessel with an 8h residence time. Furthermore, productivity at identical total residence times was 12% higher for operation with 3 cSSF stages than for a single CSTR stage for pretreated corn stover.
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Affiliation(s)
- Simone Brethauer
- University of California Riverside, Bourns College of Engineering, CE-CERT, Columbia Avenue, Riverside, CA 92507, United States
| | - Michael H Studer
- University of California Riverside, Bourns College of Engineering, CE-CERT, Columbia Avenue, Riverside, CA 92507, United States
| | - Charles E Wyman
- University of California Riverside, Bourns College of Engineering, CE-CERT, Columbia Avenue, Riverside, CA 92507, United States.
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30
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Ciesielski PN, Wang W, Chen X, Vinzant TB, Tucker MP, Decker SR, Himmel ME, Johnson DK, Donohoe BS. Effect of mechanical disruption on the effectiveness of three reactors used for dilute acid pretreatment of corn stover Part 2: morphological and structural substrate analysis. Biotechnol Biofuels 2014; 7:47. [PMID: 24690534 PMCID: PMC4022059 DOI: 10.1186/1754-6834-7-47] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Accepted: 03/17/2014] [Indexed: 05/18/2023]
Abstract
BACKGROUND Lignocellulosic biomass is a renewable, naturally mass-produced form of stored solar energy. Thermochemical pretreatment processes have been developed to address the challenge of biomass recalcitrance, however the optimization, cost reduction, and scalability of these processes remain as obstacles to the adoption of biofuel production processes at the industrial scale. In this study, we demonstrate that the type of reactor in which pretreatment is carried out can profoundly alter the micro- and nanostructure of the pretreated materials and dramatically affect the subsequent efficiency, and thus cost, of enzymatic conversion of cellulose. RESULTS Multi-scale microscopy and quantitative image analysis was used to investigate the impact of different biomass pretreatment reactor configurations on plant cell wall structure. We identify correlations between enzymatic digestibility and geometric descriptors derived from the image data. Corn stover feedstock was pretreated under the same nominal conditions for dilute acid pretreatment (2.0 wt% H2SO4, 160°C, 5 min) using three representative types of reactors: ZipperClave® (ZC), steam gun (SG), and horizontal screw (HS) reactors. After 96 h of enzymatic digestion, biomass treated in the SG and HS reactors achieved much higher cellulose conversions, 88% and 95%, respectively, compared to the conversion obtained using the ZC reactor (68%). Imaging at the micro- and nanoscales revealed that the superior performance of the SG and HS reactors could be explained by reduced particle size, cellular dislocation, increased surface roughness, delamination, and nanofibrillation generated within the biomass particles during pretreatment. CONCLUSIONS Increased cellular dislocation, surface roughness, delamination, and nanofibrillation revealed by direct observation of the micro- and nanoscale change in accessibility explains the superior performance of reactors that augment pretreatment with physical energy.
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Affiliation(s)
- Peter N Ciesielski
- Biosciences Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO, 80401, USA
| | - Wei Wang
- Biosciences Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO, 80401, USA
| | - Xiaowen Chen
- National Bioenergy Center, National Renewable Energy Laboratory, Golden, CO, USA
| | - Todd B Vinzant
- Biosciences Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO, 80401, USA
| | - Melvin P Tucker
- National Bioenergy Center, National Renewable Energy Laboratory, Golden, CO, USA
| | - Stephen R Decker
- Biosciences Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO, 80401, USA
| | - Michael E Himmel
- Biosciences Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO, 80401, USA
| | - David K Johnson
- Biosciences Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO, 80401, USA
| | - Bryon S Donohoe
- Biosciences Center, National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, CO, 80401, USA
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Li Z, Jiang Z, Fei B, Cai Z, Pan X. Comparison of bamboo green, timber and yellow in sulfite, sulfuric acid and sodium hydroxide pretreatments for enzymatic saccharification. Bioresour Technol 2014; 151:91-9. [PMID: 24212128 DOI: 10.1016/j.biortech.2013.10.060] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [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: 08/04/2013] [Revised: 10/15/2013] [Accepted: 10/17/2013] [Indexed: 05/27/2023]
Abstract
The response and behavior of bamboo green, timber, and yellow of moso bamboo (Phyllostachys heterocycla) to three pretreatments, sulfite (SPORL), dilute acid (DA), and alkali (NaOH), were investigated and compared with varied chemical loadings at 180°C for 30 min with a 6.25:1 (v/w) liquor-to-bamboo ratio. All the pretreatments improved the enzymatic digestibility of bamboo substrates. Under the investigated conditions, the DA pretreatment achieved better enzymatic digestibility, but had lower sugar recovery yield, and formed more fermentation inhibitors. The results suggested that the SPORL pretreatment be able to generate more readily digestible bamboo substrate with higher sugar yield and fewer fermentation inhibitors than the corresponding DA pretreatment if hemicelluloses are sufficiently removed by adding more acid to bring down the pretreatment pH. Bamboo timber had higher sugar content and better enzymatic digestibility and therefore was a better feedstock for bioconversion than bamboo green and yellow.
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Affiliation(s)
- Zhiqiang Li
- International Centre for Bamboo and Rattan, Beijing 100102, China
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32
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Teramura H, Oshima T, Matsuda F, Sasaki K, Ogino C, Yamasaki M, Kondo A. Glucose content in the liquid hydrolysate after dilute acid pretreatment is affected by the starch content in rice straw. Bioresour Technol 2013; 149:520-524. [PMID: 24140898 DOI: 10.1016/j.biortech.2013.09.109] [Citation(s) in RCA: 6] [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: 07/23/2013] [Revised: 09/20/2013] [Accepted: 09/24/2013] [Indexed: 06/02/2023]
Abstract
Lignocellulosic biomass, such as rice straw, is often utilized as a bioresource after being hydrolyzed using dilute acid and separated into liquid hydrolysate and acid-insoluble residue. However, the biomass component that determines the distribution between liquid hydrolysate and acid-insoluble residue has not yet been clarified. In this study, the glucose content in the liquid hydrolysate and weight of acid-insoluble residue of 13 rice cultivars were analyzed. Starch content was positively correlated with glucose content in the liquid hydrolysate, and negatively correlated with acid-insoluble residue weight. These results indicate that the glucose in the liquid hydrolysate is mainly liberated from starch rather than cellulose in the rice straw. These observations suggest that starch content is a good indicator of the glucose distribution between the liquid hydrolysate and insoluble residue.
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Affiliation(s)
- Hiroshi Teramura
- Department of Chemical Science and Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodaicho, Nada-ku, Kobe, Hyogo 657-8501, Japan
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Kim SB, Cui C, Lee JH, Lee SJ, Ahn DJ, Park C, Kim JS, Kim SW. Rapid analysis of barley straw before and after dilute sulfuric acid pretreatment by photoluminescence. Bioresour Technol 2013; 146:789-793. [PMID: 23972397 DOI: 10.1016/j.biortech.2013.07.150] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2013] [Revised: 07/29/2013] [Accepted: 07/31/2013] [Indexed: 06/02/2023]
Abstract
The fluorescence intensities (FIs) of raw and pretreated barley straws were measured by fluorescence microscopy, and the difference in the fluorescence intensity of barley straw before and after dilute acid pretreatment was analyzed by investigation of the major compounds of barley straw. The difference in fluorescence intensity was due to the difference in xylan content. Barley straw was pretreated using dilute sulfuric acid at various conditions and the correlation between the fluorescence intensity and glucose yield of barley straw was investigated. The coefficient of determination (R(2)) of the correlation was found to be 72.28%. Also the calibration of fluorescence intensity with the xylan content was performed. In addition, the absorption and emission spectra of the raw and the pretreated barley straw were examined to verify the proposed method. The absorption and emission wave lengths were 550 nm and 665 nm, respectively.
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Affiliation(s)
- Sung Bong Kim
- Department of Chemical and Biological Engineering, Korea University, Anam-Dong, Sungbuk-Gu, Seoul, Republic of Korea.
| | - Chunzhi Cui
- Department of Chemical and Biological Engineering, Korea University, Anam-Dong, Sungbuk-Gu, Seoul, Republic of Korea.
| | - Ja Hyun Lee
- Department of Chemical and Biological Engineering, Korea University, Anam-Dong, Sungbuk-Gu, Seoul, Republic of Korea.
| | - Sang Jun Lee
- Department of Chemical and Biological Engineering, Korea University, Anam-Dong, Sungbuk-Gu, Seoul, Republic of Korea.
| | - Dong June Ahn
- Department of Chemical and Biological Engineering, Korea University, Anam-Dong, Sungbuk-Gu, Seoul, Republic of Korea.
| | - Chulhwan Park
- Department of Chemical Engineering, Kwangwoon University, Wolgye-Dong, Nowon-Gu, Seoul, Republic of Korea.
| | - Jun Seok Kim
- Department of Chemical Engineering, Kyonggi University, Iui-Dong, Yeongtong-Gu, Suwon, Republic of Korea.
| | - Seung Wook Kim
- Department of Chemical and Biological Engineering, Korea University, Anam-Dong, Sungbuk-Gu, Seoul, Republic of Korea.
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Kim SB, Lee SJ, Lee JH, Jung YR, Thapa LP, Kim JS, Um Y, Park C, Kim SW. Pretreatment of rice straw with combined process using dilute sulfuric acid and aqueous ammonia. Biotechnol Biofuels 2013; 6:109. [PMID: 23898802 PMCID: PMC3734028 DOI: 10.1186/1754-6834-6-109] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2013] [Accepted: 07/26/2013] [Indexed: 05/06/2023]
Abstract
BACKGROUND Use of lignocellulosic biomass has received attention lately because it can be converted into various versatile chemical compounds by biological processes. In this study, a two-step pretreatment with dilute sulfuric acid and aqueous ammonia was performed efficiently on rice straw to obtain fermentable sugar. The soaking in aqueous ammonia process was also optimized by a statistical method. RESULTS Response surface methodology was employed. The determination coefficient (R(2)) value was found to be 0.9607 and the coefficient of variance was 6.77. The optimal pretreatment conditions were a temperature of 42.75°C, an aqueous ammonia concentration of 20.93%, and a reaction time of 48 h. The optimal enzyme concentration for saccharification was 30 filter paper units. The crystallinity index was approximately 60.23% and the Fourier transform infrared results showed the distinct peaks of glucan. Ethanol production using Saccharomyces cerevisiae K35 was performed to verify whether the glucose saccharified from rice straw was fermentable. CONCLUSIONS The combined pretreatment using dilute sulfuric acid and aqueous ammonia on rice straw efficiently yielded fermentable sugar and achieved almost the same crystallinity index as that of α-cellulose.
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Affiliation(s)
- Sung Bong Kim
- Department of Chemical and Biological Engineering, Korea University, Seoul, 136-701, South Korea
| | - Sang Jun Lee
- Department of Chemical and Biological Engineering, Korea University, Seoul, 136-701, South Korea
| | - Ju Hun Lee
- Department of Chemical and Biological Engineering, Korea University, Seoul, 136-701, South Korea
| | - You Ree Jung
- Department of Chemical and Biological Engineering, Korea University, Seoul, 136-701, South Korea
| | - Laxmi Prasad Thapa
- Department of Chemical and Biological Engineering, Korea University, Seoul, 136-701, South Korea
| | - Jun Seok Kim
- Department of Chemical Engineering, Kyonggi University, Suwon 443-760, South Korea
| | - Youngsoon Um
- Clean Energy Research Center, Korea Institute of Science and Technology, Seoul 136-791, South Korea
| | - Chulhwan Park
- Department of Chemical Engineering, Kwangwoon University, Seoul 139-701, South Korea
| | - Seung Wook Kim
- Department of Chemical and Biological Engineering, Korea University, Seoul, 136-701, South Korea
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