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Shakeel U, Zhang Y, Topakas E, Wang W, Liang C, Qi W. Unraveling interplay between lignocellulosic structures caused by chemical pretreatments in enhancing enzymatic hydrolysis. Carbohydr Polym 2024; 334:122037. [PMID: 38553235 DOI: 10.1016/j.carbpol.2024.122037] [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: 09/13/2023] [Revised: 03/01/2024] [Accepted: 03/07/2024] [Indexed: 04/02/2024]
Abstract
To investigate the interplay between substrate structure and enzymatic hydrolysis (EH) efficiency, poplar was pretreated with acidic sodium-chlorite (ASC), 3 % sodium-hydroxide (3-SH), and 3 % sulfuric acid (3-SA), resulting in different glucose yields of 94.10 %, 74.35 %, and 24.51 %, respectively, of pretreated residues. Residues were fractionated into cellulose, lignin and unhydrolyzed residue after EH (for lignin-carbohydrate complex (LCC) analysis) and analyzed using HPLC, FTIR, XPS, CP MAS 13C NMR and 2D-NMR (Lignin and LCC analysis). After delignification, holocellulose exhibited a dramatic increase in glucose yield (74.35 % to 90.82 % for 3-SH and 24.51 % to 80.0 % for 3-SA). Structural analysis of holocellulose suggested the synergistic interplay among cellulose allomorphs to limit glucose yield. Residual lignin analysis from un/pretreated residues indicated that higher β-β' contents and S/G ratios were favorable to the inhibitory effect but unfavourable to the holocellulose digestibility and followed the trend in the following order: 3-SA (L3) > 3-SH (L2) > native-lignin (L1). Analysis of enzymatically unhydrolyzed pretreated residues revealed the presence of benzyl ether (BE1,2) LCC and phenyl glycoside (PG) bond linking to xylose (X) and mannose (M), which yielded a xylan-lignin-glucomannan network. The stability, steric hindrance and hydrophobicity of this network may play a central role in defining poplar recalcitrance.
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Affiliation(s)
- Usama Shakeel
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, CAS Key Laboratory of Renewable Energy, Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China
| | - Yu Zhang
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, CAS Key Laboratory of Renewable Energy, Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China.
| | - Evangelos Topakas
- InduBioCat Group, Biotechnology Laboratory, School of Chemical Engineering, National Technical University of Athens, Athens 15780, Greece
| | - Wen Wang
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, CAS Key Laboratory of Renewable Energy, Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China
| | - Cuiyi Liang
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, CAS Key Laboratory of Renewable Energy, Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China
| | - Wei Qi
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, CAS Key Laboratory of Renewable Energy, Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China.
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Shakeel U, Zhang Y, Liang C, Wang W, Qi W. Unrevealing the influence of reagent properties on disruption and digestibility of lignocellulosic biomass during alkaline pretreatment. Int J Biol Macromol 2024; 266:131193. [PMID: 38552703 DOI: 10.1016/j.ijbiomac.2024.131193] [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: 10/26/2023] [Revised: 03/21/2024] [Accepted: 03/26/2024] [Indexed: 04/01/2024]
Abstract
Beyond the conventional consideration of pretreatment severity (PS) responsible for biomass disruption, the influence of reagent properties on biomass (LCB) disruption is often overlooked. To investigate the LCB disruption as a function of reagent properties, reagents with distinct cations (NaOH and KOH) and significantly higher delignification potential were chosen. NaOH solution (3 % w/v) with a measured pH of 13.05 ± 0.01 is considered the reference, against which a KOH solution (pH = 13.05 ± 0.01) was prepared for LCB pretreatment under the same PS. Despite comparable lignin content, varying glucose yield of NaOH (68.76 %) and KOH (46.88 %) pretreated residues indicated the presence of heterogeneously disrupted substrate. Holocellulose extracted from raw poplar (ASC, control) and alkaline pretreated residues (C-NaOH and C-KOH) were analyzed using HPLC, XRD, SEM, TGA/DTG, XPS, and 13CP MAS NMR to investigate the pretreatment-induced structural modification. Results revealed that, despite the same pretreatment severity, better disruption in C-NaOH (higher accessible fibril surface and less-ordered region) leading to higher digestibility than C-KOH, likely due to the smaller ionic radius of Na+, facilitates better penetration into dense LCB matrix. This study elucidates the importance of considering the reagent properties during LCB pretreatment, eventually enhancing consciousness while selecting reagents for efficient LCB utilization.
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Affiliation(s)
- Usama Shakeel
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China; CAS Key Laboratory of Renewable Energy, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China
| | - Yu Zhang
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China; CAS Key Laboratory of Renewable Energy, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China.
| | - Cuiyi Liang
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China; CAS Key Laboratory of Renewable Energy, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China
| | - Wen Wang
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China; CAS Key Laboratory of Renewable Energy, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China
| | - Wei Qi
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China; CAS Key Laboratory of Renewable Energy, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China.
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Qi W, Feng Q, Wang W, Zhang Y, Hu Y, Shakeel U, Xiao L, Wang L, Chen H, Liang C. Combination of surfactants and enzyme cocktails for enhancing woody biomass saccharification and bioethanol production from lab-scale to pilot-scale. Bioresour Technol 2023:129343. [PMID: 37348567 DOI: 10.1016/j.biortech.2023.129343] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 06/14/2023] [Accepted: 06/15/2023] [Indexed: 06/24/2023]
Abstract
Converting woody biomass to bioethanol might be more affordable, environmentally friendly, and efficient for making biofuel commercially feasible, but it would still need a significant optimization process and expand pilot-scale research. A combination of commercial low enzymes loading at 10 FPU/g glucan and compound additives utilizing Tween 80, PEG8000 and sophorolipid applied from lab-scale to pilot-scale have been studied in this work at economically viable dosages for enhancing bioethanol production. In lab-scale saccharification and fermentation, pretreated poplar at a high solid loading of 20% yielded the highest ethanol titers of 30.96 g/L and theoretical ethanol yield of 92.79%. Additionally, pilot-scale operation was used to investigate the bioethanol amplification, a final volume of 33 m3 which yielded the greatest ethanol amount of 599.6 kg from poplar wood while gaining on-site value-added production of hemicellulosic and cellobiose liquor 1122 kg and lignin residues 2292 kg.
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Affiliation(s)
- Wei Qi
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qifa Feng
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wen Wang
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yu Zhang
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yunzi Hu
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China
| | - Usama Shakeel
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China
| | - Lin Xiao
- Longlive Bio-technology Co., Ltd., Yucheng City, Shandong Province 251200, China
| | - Lan Wang
- State Key Laboratory of Biochemical Engineering, Beijing Key Laboratory of Biomass Refining Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Hongzhang Chen
- State Key Laboratory of Biochemical Engineering, Beijing Key Laboratory of Biomass Refining Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
| | - Cuiyi Liang
- Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China.
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Singh J, Shakeel U, Ompong D, Ram KS. Intersystem and Reverse-Intersystem Crossings in Organic Light-Emitting Diodes. J Phys Chem Lett 2022; 13:6177-6180. [PMID: 35767001 DOI: 10.1021/acs.jpclett.2c01194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Using the first-order perturbation theory and exciton-spin-orbit-photon-molecular-vibration-interaction (ESOPMVI) operator, the rates of reverse intersystem crossing (RISC) and thermally activated delayed fluorescence (TADF) are derived. It is shown that the pre-exponential factor of the rate of TADF is not an absolute constant as is commonly assumed. Instead, it depends on the square of the atomic number and the exchange energy, but it also depends on the triplet excitonic Bohr radius as at-6, which enhances the rate of RISC by 4-6 orders of magnitude higher than the rate of the intersystem crossing, which undermines the dependence of the rate on the atomic number, and hence TADF can occur efficiently in metal-free organic solids. This provides a clearer understanding of the mechanism of TADF in metal-free organic light-emitting diodes as has been found recently experimentally.
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Affiliation(s)
- Jai Singh
- College of Engineering, IT and Environment and Energy Resources Institute, Charles Darwin University, Darwin 0909, Northern Territory, Australia
| | - U Shakeel
- College of Engineering, IT and Environment and Energy Resources Institute, Charles Darwin University, Darwin 0909, Northern Territory, Australia
| | - David Ompong
- College of Engineering, IT and Environment and Energy Resources Institute, Charles Darwin University, Darwin 0909, Northern Territory, Australia
| | - Kiran Sreedhar Ram
- College of Engineering, IT and Environment and Energy Resources Institute, Charles Darwin University, Darwin 0909, Northern Territory, Australia
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Shakeel U, Hussain M, Sheikh R, Ahmed A, Nazir MS, Yang W, Shezad N, Akhter P, Park YK. Development of highly efficient solid acid catalysts supported on mesoporous KIT-6 for esterification of oleic acid. KOREAN J CHEM ENG 2021. [DOI: 10.1007/s11814-021-0754-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Siddiqui Z, Shakeel U, Siddiqui S. Biocontrol of wilt disease complex of pigeonpea by fluorescent pseudomonads andBacillusspp. under pot and field conditions. ACTA ACUST UNITED AC 2008. [DOI: 10.1556/aphyt.43.2008.1.10] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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