Pretreatment of sweet sorghum straw and its enzymatic digestion: insight into the structural changes and visualization of hydrolysis process
Abstract Background The efficient utilization of lignocellulosic biomass for biofuel production has received increasing attention. Previous studies have investigated the pretreatment process of biomass, but the detailed enzymatic hydrolysis process of pretreated biomass remains largely unclear. Thus...
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| Format: | Article |
| Language: | English |
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BMC
2019-11-01
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| Series: | Biotechnology for Biofuels |
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| Online Access: | http://link.springer.com/article/10.1186/s13068-019-1613-6 |
| _version_ | 1828340683779342336 |
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| author | Miaoyin Dong Shuyang Wang Fuqiang Xu Junkai Wang Ning Yang Qiaoqiao Li Jihong Chen Wenjian Li |
| author_facet | Miaoyin Dong Shuyang Wang Fuqiang Xu Junkai Wang Ning Yang Qiaoqiao Li Jihong Chen Wenjian Li |
| author_sort | Miaoyin Dong |
| collection | DOAJ |
| description | Abstract Background The efficient utilization of lignocellulosic biomass for biofuel production has received increasing attention. Previous studies have investigated the pretreatment process of biomass, but the detailed enzymatic hydrolysis process of pretreated biomass remains largely unclear. Thus, this study investigated the pretreatment efficiency of dilute alkali, acid, hydrogen peroxide and its ultimate effects on enzymatic hydrolysis. Furthermore, to better understand the enzymatic digestion process of alkali-pretreated sweet sorghum straw (SSS), multimodal microscopy techniques were used to visualize the enzymatic hydrolysis process. Result After pretreatment with alkali, an enzymatic hydrolysis efficiency of 86.44% was obtained, which increased by 99.54% compared to the untreated straw (43.23%). The FTIR, XRD and SEM characterization revealed a sequence of microstructural changes occurring in plant cell walls after pretreatment, including the destruction of lignin–polysaccharide interactions, the increase of porosity and crystallinity, and reduction of recalcitrance. During the course of hydrolysis, the cellulase dissolved the cell walls in the same manner and the digestion firstly occurred from the middle of cell walls and then toward the cell wall corners. The CLSM coupled with fluorescent labeling demonstrated that the sclerenchyma cells and vascular bundles in natural SSS were highly lignified, which caused the nonproductive bindings of cellulase on lignin. However, the efficient delignification significantly increased the accessibility and digestibility of cellulase to biomass, thereby improving the saccharification efficiency. Conclusion This work will be helpful in investigating the biomass pretreatment and its structural characterization. In addition, the visualization results of the enzymatic hydrolysis process of pretreated lignocellulose could be used for guidance to explore the lignocellulosic biomass processing and large-scale biofuel production. |
| first_indexed | 2024-04-13T22:59:43Z |
| format | Article |
| id | doaj.art-9a1d7e7c3c994a95bf6b9df88cab5ea5 |
| institution | Directory Open Access Journal |
| issn | 1754-6834 |
| language | English |
| last_indexed | 2024-04-13T22:59:43Z |
| publishDate | 2019-11-01 |
| publisher | BMC |
| record_format | Article |
| series | Biotechnology for Biofuels |
| spelling | doaj.art-9a1d7e7c3c994a95bf6b9df88cab5ea52022-12-22T02:25:53ZengBMCBiotechnology for Biofuels1754-68342019-11-0112111110.1186/s13068-019-1613-6Pretreatment of sweet sorghum straw and its enzymatic digestion: insight into the structural changes and visualization of hydrolysis processMiaoyin Dong0Shuyang Wang1Fuqiang Xu2Junkai Wang3Ning Yang4Qiaoqiao Li5Jihong Chen6Wenjian Li7Institute of Modern Physics, Chinese Academy of SciencesInstitute of Modern Physics, Chinese Academy of SciencesInstitute of Modern Physics, Chinese Academy of SciencesCollege of Physics and Electronic Engineering, Northwest Normal UniversityCollege of Life Sciences, Northwest Normal UniversityInstitute of Modern Physics, Chinese Academy of SciencesInstitute of Modern Physics, Chinese Academy of SciencesInstitute of Modern Physics, Chinese Academy of SciencesAbstract Background The efficient utilization of lignocellulosic biomass for biofuel production has received increasing attention. Previous studies have investigated the pretreatment process of biomass, but the detailed enzymatic hydrolysis process of pretreated biomass remains largely unclear. Thus, this study investigated the pretreatment efficiency of dilute alkali, acid, hydrogen peroxide and its ultimate effects on enzymatic hydrolysis. Furthermore, to better understand the enzymatic digestion process of alkali-pretreated sweet sorghum straw (SSS), multimodal microscopy techniques were used to visualize the enzymatic hydrolysis process. Result After pretreatment with alkali, an enzymatic hydrolysis efficiency of 86.44% was obtained, which increased by 99.54% compared to the untreated straw (43.23%). The FTIR, XRD and SEM characterization revealed a sequence of microstructural changes occurring in plant cell walls after pretreatment, including the destruction of lignin–polysaccharide interactions, the increase of porosity and crystallinity, and reduction of recalcitrance. During the course of hydrolysis, the cellulase dissolved the cell walls in the same manner and the digestion firstly occurred from the middle of cell walls and then toward the cell wall corners. The CLSM coupled with fluorescent labeling demonstrated that the sclerenchyma cells and vascular bundles in natural SSS were highly lignified, which caused the nonproductive bindings of cellulase on lignin. However, the efficient delignification significantly increased the accessibility and digestibility of cellulase to biomass, thereby improving the saccharification efficiency. Conclusion This work will be helpful in investigating the biomass pretreatment and its structural characterization. In addition, the visualization results of the enzymatic hydrolysis process of pretreated lignocellulose could be used for guidance to explore the lignocellulosic biomass processing and large-scale biofuel production.http://link.springer.com/article/10.1186/s13068-019-1613-6Sweet sorghum strawPretreatmentStructural characterizationEnzymatic hydrolysis processVisualization |
| spellingShingle | Miaoyin Dong Shuyang Wang Fuqiang Xu Junkai Wang Ning Yang Qiaoqiao Li Jihong Chen Wenjian Li Pretreatment of sweet sorghum straw and its enzymatic digestion: insight into the structural changes and visualization of hydrolysis process Biotechnology for Biofuels Sweet sorghum straw Pretreatment Structural characterization Enzymatic hydrolysis process Visualization |
| title | Pretreatment of sweet sorghum straw and its enzymatic digestion: insight into the structural changes and visualization of hydrolysis process |
| title_full | Pretreatment of sweet sorghum straw and its enzymatic digestion: insight into the structural changes and visualization of hydrolysis process |
| title_fullStr | Pretreatment of sweet sorghum straw and its enzymatic digestion: insight into the structural changes and visualization of hydrolysis process |
| title_full_unstemmed | Pretreatment of sweet sorghum straw and its enzymatic digestion: insight into the structural changes and visualization of hydrolysis process |
| title_short | Pretreatment of sweet sorghum straw and its enzymatic digestion: insight into the structural changes and visualization of hydrolysis process |
| title_sort | pretreatment of sweet sorghum straw and its enzymatic digestion insight into the structural changes and visualization of hydrolysis process |
| topic | Sweet sorghum straw Pretreatment Structural characterization Enzymatic hydrolysis process Visualization |
| url | http://link.springer.com/article/10.1186/s13068-019-1613-6 |
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