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1.
ChemSusChem ; 17(8): e202301161, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38123529

RESUMO

Current DES pretreatment is often performed under relatively severe conditions with high temperature, long time, and high DES usage. This work studied a short-time diol DES (deep eutectic solvent) pretreatment under mild conditions to fractionate the bamboo, facilitate enzymatic hydrolysis, and obtain high-quality lignin. At an optimized condition of 130 °C for only 10 min, lignin and xylan removal reached 61.34 % and 84.15 %, with residual glucan showing a ~90 % enzymatic hydrolysis yield. Equally important, the dissolved lignin could be readily recovered with 97.51 % yield, exhibiting 96.65 % ß-O-4 preservation. The fractionation and lignin protection mechanisms were unveiled by XRD, FTIR, cellulose-DP, 2D HSQC NMR, 31P NMR and GPC analysis. This study highlighted that short-time fractionation of bamboo can be achieved by a diol-based DES which is an ideal strategy to upgrade the lignocellulose biomass for high enzymatic hydrolysis yields and high-quality lignin stream.


Assuntos
Biomassa , Fracionamento Químico , Lignina , Lignina/química , Hidrólise , Fracionamento Químico/métodos , Solventes Eutéticos Profundos/química , Celulase/química , Solventes/química
2.
Bioresour Technol ; 387: 129653, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37573979

RESUMO

The failure of hemicellulose valorization in a deep eutectic solvent (DES) pretreatment has become a bottleneck that challenges its further development. To address this issue, this study developed a DES/GVL (γ-valerolactone) biphasic system for effective hemicellulose-furfural conversion, enhanced cellulose saccharification and lignin isolation. The results indicated that the biphasic system could significantly improve the lignin removal (as high as 89.1%), 86.0% higher than the monophasic DES, accompanied by âˆ¼100% hemicellulose degradation. Notably, the GVL in the biphasic solvent restricted the condensation of hemicellulose degradation products, which as a result generated large amount of furfural in the pretreatment liquid with a yield of 68.6%. With the removal of hemicellulose and lignin, cellulose enzymatic hydrolysis yield was boosted and reached near 100%. This study highlighted that the novel DES/GVL is capable of fractionating the biomass and benefiting their individual utilization, which could provide a new biorefinery configuration for a DES pretreatment.


Assuntos
Furaldeído , Lignina , Lignina/metabolismo , Solventes Eutéticos Profundos , Biomassa , Hidrólise , Solventes , Celulose , Minerais
3.
Sci Rep ; 13(1): 3999, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36899028

RESUMO

In this paper, we take the four-way shuttle system as the research object and establish the mathematical model of scheduling optimization based on the minimum time for the in/out operation optimization and path optimization scheduling problems of the four-way shuttle system. An improved genetic algorithm is used to solve the task planning, and an improved A* algorithm is used to solve the path optimization within the shelf level. The conflicts generated by the parallel operation of the four-way shuttle system are classified, and the improved A* algorithm based on the time window method is constructed for path optimization through the dynamic graph theory method to seek safe conflict-free paths. Through simulation example analysis, it is verified that the improved A* algorithm proposed in this paper has obvious optimization effect on the model of this paper.

4.
Bioresour Technol ; 367: 128297, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36370941

RESUMO

Herein, a Na2S promoted deep eutectic solvent (DES) was established to reduce the natural recalcitrance of moso bamboo (MB) and improve the subsequent enzymatic saccharification. It was found that the addition of Na2S (Choline chloride/Ethylene glycol/Na2S) dramatically promoted the deconstructions of lignin with highest removal of 74.67 %, but at the same time preserved glucan and hemicellulose to the maximum extent. With the fractionation, the enzymatic saccharification yield of pretreated MB can reach 100 % under the pretreatment condition of 140 °C, and lignin could be readily recovered with a high yield of 81.47 %. The proposed DES is superior to normal alkaline DES in terms of the higher lignin removal and recovery yield, carbohydrate preservation and enzymatic digestibility, which indicated Na2S as a novel and powerful reinforcer enhancing the DES fractionation efficiency.


Assuntos
Solventes Eutéticos Profundos , Lignina , Biomassa , Álcalis , Solventes , Poaceae , Hidrólise
5.
Bioresour Technol ; 362: 127771, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35964916

RESUMO

This study proposed a renewable deep eutectic solvent (DES) pretreatment using lignin-derived guaiacol as the hydrogen bond donor. The DES showed excellent biomass fractionation efficiency after the incorporation of trace AlCl3 as the reinforcer, which removed 79.1 % lignin while preserving more than 90 % glucan. The pretreated bamboo exhibited 96.2 % glucan enzymatic hydrolysis yield at only 110 °C. The physicochemical properties of the pretreated solids were comprehensively investigated to explain how the DES fractionation overcame the biomass recalcitrance. The regenerated lignin from the DES pretreatment was also analyzed, which revealed that lignin ß-O-4 bond was significantly cleaved. This guaiacol-based DES could greatly contribute to establish a closed-loop biorefinery sequence with high lignin fractionation efficiency and great solvent recyclability.


Assuntos
Solventes Eutéticos Profundos , Lignina , Biomassa , Guaiacol , Hidrólise , Lignina/química , Solventes/química
6.
Bioresour Technol ; 359: 127462, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35700894

RESUMO

A delignification saturation point (DSP) was observed for bamboo alkaline hydrogen peroxide pretreatment (AHP). Lignin removal was increased from 52.23% to ∼70% when increasing H2O2 dosage from 0% to 2% at the optimum pH, but it cannot be further reinforced as increasing the H2O2. With partial lignin preserved, the glucan hydrolysis yield was found to have a ceiling of ∼80%. This study indicated a strong association between enzymatic digestibility and lignin removal. Anatomical analysis by fluorescence microscope and confocal Raman microscope revealed that the undegradable lignin was mainly existing in the cell corner of sclerenchyma fibers, causing the DSP in the bamboo AHP. Finally, the residual lignin in pretreated bamboo was characterized with GPC, HSQC NMR, and 31P NMR, which revealed the nature of DSP. This study could help to understand the lignin modification during the AHP and further contribute to the establishment of a chemical-saving biorefinery.


Assuntos
Peróxido de Hidrogênio , Lignina , Glucanos , Hidrólise , Lignina/química
7.
Bioresour Technol ; 349: 126854, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35176465

RESUMO

This study comprehensively investigated two bamboo species (i.e. Neosinocalamus affinis and Phyllostachys edulis) in terms of their cell wall ultrastructure, chemical compositions, enzymatic saccharification, and lignin structure before and after alkaline hydrogen peroxide pretreatment (AHP). During AHP, Neosinocalamus affinis (NAB) had higher delignification than Phyllostachys edulis (PEB), and thus showed better enzymatic digestibility (93.05% vs 53.57% for glucan). The fundamental chemical behavior of the bamboo lignins was analyzed by fluorescence microscope (FM), confocal Raman microscope (CRM), molecular weight analysis, and 2D HSQC-NMR. Results indicated that the PEB has thicker cell wall and more concentrated lignin in its compound middle lamella and cell corner middle lamella than NAB. Moreover, PEB lignin contains more G units (S/G of 0.95), in evident contrast to that of NAB lignin (S/G of 1.30), which favor the formation of C-C linkages, thus impeding its degradation during the AHP.


Assuntos
Bambusa , Peróxido de Hidrogênio , Bambusa/química , Hidrólise , Lignina/química , Açúcares
8.
Bioresour Technol ; 326: 124696, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33508646

RESUMO

Herein, we established a novel deep eutectic solvent (DES) using lignin-derived guaiacol as hydrogen bond donor (HBD). The sole ChCl/guaiacol system was found to be inefficient for the fractionation of wheat straw (WS), while the incorporation of trace AlCl3 significantly facilitated the degradation of hemicellulose and lignin, resulting in a complete enzymatic digestibility of the pretreated WS. Further, this study revealed that the DES-degraded lignin was readily precipitated during the washing process, and thus hindered the enzymatic hydrolysis of poplar and bamboo (with hydrolysis yield of 42.03% and 71.67%, respectively). Alkali washing offers a possible approach to remove the precipitated lignin, after which a near 100% hydrolysis yield was also obtained for poplar and bamboo.


Assuntos
Guaiacol , Lignina , Biomassa , Hidrólise , Solventes
9.
Shock ; 55(1): 90-99, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-32433207

RESUMO

INTRODUCTION: Sepsis is a kind of maladjustment response to bacterial infection and activation of coagulation, which can induce neuromuscular dysfunction. However, there is scarce of experimental evidence about the relationship between Schwann cells (SCs) and sepsis in neuromuscular dysfunction. We therefore set out to identify the potential role of SCs in sepsis-induced neuromuscular dysfunction and to explore the underlying molecular mechanism. METHODS: Primary SCs were isolated from the left hind limb sciatic nerve of sepsis mice, which was constructed by cecal ligation and puncture. Then, the SCs were infected with adenovirus encoding toll-like receptor 4 (TLR4), MyD88, or IL-1R (with lipopolysaccharide stimulation), and the Raw 264.7 macrophages were injected with adenovirus with CCR2 silencing (with mMCP-1 stimulation). Further investigation of the interleukin 1 beta (IL-1ß) and macrophage cationic peptide 1 (MCP-1) expressions, we followed reverse transcription-quantitative polymerase chain reaction and enzyme-linked immunosorbent assay techniques, the F4/80 and Ki67 expressions was observed by immunofluorescence staining, while the expressions of CCR2, FAK/p-FAK, nuclear factor-κB (NFκB)/p-NFκB, and ERK1/2/p-ERK1/2 were determined by Western blot analysis. Last, but not the least, the cell migration ability and cell proliferation ability were detected by Transwell assay and Flow cytometry respectively. RESULTS: Our results showed that in sepsis mice, the TLR4/MyD88/ERK pathway was activated in SCs, which triggered the cells to secrete IL-1ß and MCP-1. The secreted IL-1ß bound with IL-1ß receptor on the surface of SCs, thereby activating the IL-1ß/IL-1R/MyD88/ERK pathway and further promoting the secretion of MCP-1 by SCs. MCP-1 was found to bind to CCR2 on the surface of Raw264.7 macrophages to activate the TLR4/MyD88/ERK pathway which caused the inhibition of neuromuscular function. CONCLUSION: Sepsis significantly promotes the infiltration of macrophages by activating the TLR4/MyD88 pathway in SCs, thereby impeding neuromuscular function. Consistently, our study provides a novel concept in the area of neuromuscular dysfunction therapeutics following sepsis.


Assuntos
Fator 88 de Diferenciação Mieloide/metabolismo , Células de Schwann/patologia , Sepse/metabolismo , Sepse/patologia , Receptor 4 Toll-Like/metabolismo , Animais , Proliferação de Células , Quimiocina CCL2/metabolismo , Modelos Animais de Doenças , Interleucina-1beta/metabolismo , Macrófagos , Camundongos , Camundongos Endogâmicos C57BL , Atividade Motora/fisiologia , Células de Schwann/metabolismo , Sepse/complicações
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