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Simultaneous Saccharification and Fermentation of Empty Fruit Bunches of Palm for Bioethanol Production Using a Microbial Consortium of S. cerevisiae and T. harzianum. FERMENTATION-BASEL 2022. [DOI: 10.3390/fermentation8070295] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A simultaneous saccharification and fermentation (SSF) optimization process was carried out on pretreated empty fruit bunches (EFBs) by employing the Response Surface Methodology (RSM). EFBs were treated using sequential acid-alkali pretreatment and analyzed physically by a scanning electron microscope (SEM). The findings revealed that the pretreatment had changed the morphology and the EFBs’ structure. Then, the optimum combination of enzymes and microbes for bioethanol production was screened. Results showed that the combination of S. cerevisiae and T. harzianum and enzymes (cellulase and β-glucosidase) produced the highest bioethanol concentration with 11.76 g/L and a bioethanol yield of 0.29 g/g EFB using 4% (w/v) treated EFBs at 30 °C for 72 h. Next, the central composite design (CCD) of RSM was employed to optimize the SSF parameters of fermentation time, temperature, pH, and inoculum concentration for higher yield. The analysis of optimization by CCD predicted that 9.72 g/L of bioethanol (0.46 g/g ethanol yield, 90.63% conversion efficiency) could be obtained at 72 h, 30 °C, pH 4.8, and 6.79% (v/v) of inoculum concentration using 2% (w/v) treated EFBs. Results showed that the fermentation process conducted using the optimized conditions produced 9.65 g/L of bioethanol, 0.46 g/g ethanol yield, and 89.56% conversion efficiency, which was in close proximity to the predicted CCD model.
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2
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Banu Jamaldheen S, Kurade MB, Basak B, Yoo CG, Oh KK, Jeon BH, Kim TH. A review on physico-chemical delignification as a pretreatment of lignocellulosic biomass for enhanced bioconversion. BIORESOURCE TECHNOLOGY 2022; 346:126591. [PMID: 34929325 DOI: 10.1016/j.biortech.2021.126591] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2021] [Revised: 12/14/2021] [Accepted: 12/16/2021] [Indexed: 06/14/2023]
Abstract
Effective pretreatment of lignocellulosic biomass (LCB) is one of the most important steps in biorefinery, ensuring the quality and commercial viability of the overall bioprocess. Lignin recalcitrance in LCB is a major bottleneck in biological conversion as the polymerization of lignin with hemicellulose hinders enzyme accessibility and further bioconversion to fuels and chemicals. Therefore, there is a need to delignify LCB to ease further bioprocessing. The efficiency of delignification, quality and quantity of the desired products, and generation of inhibitors depend upon the type of pretreatment employed. This review summarizes different single and integrated physicochemical pretreatments for delignification. Additionally, conditions required for effective delignification and the advantages and drawbacks of each method were evaluated. Advances in overcoming the recalcitrance of residual lignin to saccharification and the methods to recover lignin after delignification are also discussed. Efficient lignin recovery and valorization strategies provide an avenue for the sustainable lignocellulose biorefinery.
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Affiliation(s)
- Sumitha Banu Jamaldheen
- Department of Materials Science and Chemical Engineering, Hanyang University, Ansan, Gyeonggi-do 15588, Republic of Korea
| | - Mayur B Kurade
- Department of Earth Resources and Environmental Engineering, Hanyang University, 222-Wangsimni-ro, Seongdong-gu, Seoul 04763, Republic of Korea
| | - Bikram Basak
- Department of Earth Resources and Environmental Engineering, Hanyang University, 222-Wangsimni-ro, Seongdong-gu, Seoul 04763, Republic of Korea
| | - Chang Geun Yoo
- Department of Chemical Engineering, State University of New York, College of Environmental Science and Forestry, Syracuse, NY 13210, USA
| | - Kyeong Keun Oh
- Department of Chemical Engineering, Dankook University, Youngin 16890, Gyeonggi-do, Republic of Korea
| | - Byong-Hun Jeon
- Department of Earth Resources and Environmental Engineering, Hanyang University, 222-Wangsimni-ro, Seongdong-gu, Seoul 04763, Republic of Korea
| | - Tae Hyun Kim
- Department of Materials Science and Chemical Engineering, Hanyang University, Ansan, Gyeonggi-do 15588, Republic of Korea.
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Production of Bio-Based Chemicals, Acetic Acid and Furfural, through Low-Acid Hydrothermal Fractionation of Pine Wood (Pinus densiflora) and Combustion Characteristics of the Residual Solid Fuel. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11167435] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Low-acid hydrothermal (LAH) fractionation conditions were optimized for the effective degradation of hemicellulose from pine wood (Pinus densiflora). The hemicellulosic sugar yield was maximized at 82.5% when the pine wood was fractionated at 190 °C, with 0.5 wt.% of sulfuric acid, and for 10 min. Consecutively, acidified heat treatment with zinc chloride and solvent extraction with ethyl acetate were carried out for the recovery of bio-based platform chemicals, such as furfural and acetic acid, from liquid hydrolysate through liquid–liquid extraction (LLE). Overall, 61.5% of xylose was decomposed into furfural, and the yield of acetic acid was 62.3% and furfural 66.1%. After LAH fractionation, 64.8% of the solid remained and was pelletized. The pellets showed excellent fuel characteristics, i.e., significant ash rejection (74.5%) and high calorific values (4770 kcal/kg), and the precursors of NOx and SOx also decreased by up to 60.0% and 71.4%, respectively.
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Effects of Organic Solvents on the Organosolv Pretreatment of Degraded Empty Fruit Bunch for Fractionation and Lignin Removal. SUSTAINABILITY 2021. [DOI: 10.3390/su13126757] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Empty fruit bunch (EFB), which is one of the primary agricultural wastes generated from the palm oil plantation, is generally discharged into the open environment or ends up in landfills. The utilization of this EFB waste for other value-added applications such as activated carbon and biofuels remain low, despite extensive research efforts. One of the reasons is that the EFB is highly vulnerable to microbial and fungi degradation under natural environment owning to its inherent characteristic of high organic matter and moisture content. This can rapidly deteriorate its quality and results in poor performance when processed into other products. However, the lignocellulosic components in degraded EFB (DEFB) still largely remain intact. Consequently, it could become a promising feedstock for production of bio-products after suitable pretreatment with organic solvents. In this study, DEFB was subjected to five different types of organic solvents for the pretreatment, including ethanol, ethylene glycol, 2-propanol, acetic acid and acetone. The effects of temperature and residence time were also investigated during the pretreatment. Organosolv pretreatment in ethylene glycol (50 v/v%) with the addition of NaOH (3 v/v%) as an alkaline catalyst successfully detached 81.5 wt.% hemicellulose and 75.1 wt.% lignin. As high as 90.4 wt.% cellulose was also successfully retrieved at mild temperature (80 °C) and short duration (45 min), while the purity of cellulose in treated DEFB was recorded at 84.3%. High-purity lignin was successfully recovered from the pretreatment liquor by using sulfuric acid for precipitation. The amount of recovered lignin from alkaline ethylene glycol liquor was 74.6% at pH 2.0. The high recovery of cellulose and lignin in DEFB by using organosolv pretreatment rendered it as one of the suitable feedstocks to be applied in downstream biorefinery processes. This can be further investigated in more detailed studies in the future.
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Shen X, Sun R. Recent advances in lignocellulose prior-fractionation for biomaterials, biochemicals, and bioenergy. Carbohydr Polym 2021; 261:117884. [PMID: 33766371 DOI: 10.1016/j.carbpol.2021.117884] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Revised: 01/25/2021] [Accepted: 02/26/2021] [Indexed: 12/20/2022]
Abstract
Due to over-consumption of fossil resources and environmental problems, lignocellulosic biomass as the most abundant and renewable materials is considered as the best candidate to produce biomaterials, biochemicals, and bioenergy, which is of strategic significance and meets the theme of Green Chemistry. Highly efficient and green fractionation of lignocellulose components significantly boosts the high-value utilization of lignocellulose and the biorefinery development. However, heterogeneity of lignocellulosic structure severely limited the lignocellulose fractionation. This paper offers the summary and perspective of the extensive investigation that aims to give insight into the lignocellulose prior-fractionation. Based on the role and structure of lignocellulose component in the plant cell wall, lignocellulose prior-fractionation can be divided into cellulose-first strategy, hemicelluloses-first strategy, and lignin-first strategy, which realizes the selective dissociation and transformation of a component in lignocellulose. Ultimately, the challenges and opportunities of lignocellulose prior-fractionation are proposed on account of the existing problems in the biorefining valorization.
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Affiliation(s)
- Xiaojun Shen
- Liaoning Key Laboratory of Lignocellulose Chemistry and BioMaterials, Dalian Polytechnic University, Dalian, 116034, China; State Key Laboratory of Catalysis (SKLC), Dalian National Laboratory for Clean Energy (DNL), Dalian, China
| | - Runcang Sun
- Liaoning Key Laboratory of Lignocellulose Chemistry and BioMaterials, Dalian Polytechnic University, Dalian, 116034, China.
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Alkaline Fractionation and Subsequent Production of Nano-Structured Silica and Cellulose Nano-Fibrils for the Comprehensive Utilization of Rice Husk. SUSTAINABILITY 2021. [DOI: 10.3390/su13041951] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The parameters of the alkaline fractionation process were investigated and optimized using a statistical analysis method to simultaneously remove hemicellulose and ash from rice husk (RH) concomitantly. After the alkaline fractionation process, the residual solid contained high cellulose, and the recovery yield of hemicellulose was enhanced in the fractionated liquid hydrolyzate. The hemicellulosic sugar recovery yield (71.6%), de-ashing yield (>99%), and lignin removal (>80%) were obtained at the reaction conditions of 150 °C of temperature, 40 min of reaction time, and 6% (w/v) of NaOH concentration. Subsequently, nano-structured silica was synthesized using black liquor obtained as a by-product of this fractionation process. For the production of nano-structured silica, it was observed that the pH of a black liquor and the heat treatment temperature significantly influenced the textural properties of silica product. In addition, the two-stage bleaching of solid residue followed by colloid milling for the production of high value-added CNF with was attempted. As a result, in addition to 119 g of fermentable sugar, 143 g of high-purity (>98%) silica with a surface area of 328 m2g−1 and 273.1 g of high-functional CNF with cellulose content of 80.1% were simultaneously obtained from 1000 g of RH.
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Recovery of High Purity Lignin and Digestible Cellulose from Oil Palm Empty Fruit Bunch Using Low Acid-Catalyzed Organosolv Pretreatment. AGRONOMY-BASEL 2020. [DOI: 10.3390/agronomy10050674] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The lignocellulosic residue from the palm oil industry, oil palm empty fruit bunch (OPEFB), represents a challenge to both producing industries and environment due to its disposal difficulties. Alternatively, OPEFB can be used for the production of valuable products if pretreatment methods, which overcome OPEFB recalcitrance and allow tailored valorization of all its carbohydrates and lignin, are developed. Specifically, high-value applications for lignin, to increase its contribution to the feasibility of lignocellulosic biorefineries, demand high-purity fractions. In this study, acid-catalyzed organosolv using ethanol as a solvent was used for the recovery of high-purity lignin and digestible cellulose. Factors including catalyst type and its concentration, temperature, retention time, and solid-to-liquid (S/L) ratio were found to influence lignin purity and recovery. At the best conditions (0.07% H2SO4, 210 °C, 90 min, and S/L ratio of 1:10), a lignin purity and recovery of 70.6 ± 4.9% and 64.94 ± 1.09%, respectively, were obtained in addition to the glucan-rich fraction. The glucan-rich fraction showed 94.06 ± 4.71% digestibility within 18 h at an enzyme loading of 30 filter paper units (FPU) /g glucan. Therefore, ethanol organosolv can be used for fractionating OPEFB into three high-quality fractions (glucan, lignin, and hemicellulosic compounds) for further tailored biorefining using low acid concentrations. Especially, the use of ethanol opens the possibility for integration of 1st and 2nd generation ethanol benefiting from the separation of high-purity lignin.
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Xiao M, Wang L, Wu Y, Cheng C, Chen L, Chen H, Xue C. Hybrid dilute sulfuric acid and aqueous ammonia pretreatment for improving butanol production from corn stover with reduced wastewater generation. BIORESOURCE TECHNOLOGY 2019; 278:460-463. [PMID: 30704901 DOI: 10.1016/j.biortech.2019.01.079] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 01/16/2019] [Accepted: 01/19/2019] [Indexed: 06/09/2023]
Abstract
An efficient hybrid pretreatment method was developed for butanol production from corn stover using dilute sulfuric acid (DA) and aqueous ammonia (AA). With the optimized AA concentration, treatment temperature and time of 10% AA, 80 °C and 24 h, the hybrid pretreatment could effectively dissolve hemicellulose and lignin with solid recovery rate of 37.45% and lignin reduction rate of 86.77% compared to those of 57.75% and 45.84% from single DA pretreatment. By washing 1 time after each step treatment, sugar yield and butanol production were increased to 401.76 mg/g-CS and 10.89 g/L from 346.04 mg/g-CS and 9.33 g/L obtained without washing. Compared with conventional single DA and AA pretreatment methods, wastewater generation was reduced to 0.83 L/g-butanol from 2.11 and 3.46 L/g-butanol, indicating this hybrid pretreatment could be an effective approach for improving butanol production from lignocellulosic feedstocks.
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Affiliation(s)
- Min Xiao
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024, China.
| | - Lan Wang
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 10090, China.
| | - Youduo Wu
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024, China.
| | - Chi Cheng
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024, China.
| | - Lijie Chen
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024, China.
| | - Hongzhang Chen
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 10090, China.
| | - Chuang Xue
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024, China.
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Ahmad FB, Zhang Z, Doherty WO, O’Hara IM. The prospect of microbial oil production and applications from oil palm biomass. Biochem Eng J 2019. [DOI: 10.1016/j.bej.2018.12.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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10
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An S, Li W, Liu Q, Xia Y, Zhang T, Huang F, Lin Q, Chen L. Combined dilute hydrochloric acid and alkaline wet oxidation pretreatment to improve sugar recovery of corn stover. BIORESOURCE TECHNOLOGY 2019; 271:283-288. [PMID: 30286394 DOI: 10.1016/j.biortech.2018.09.126] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Revised: 09/22/2018] [Accepted: 09/25/2018] [Indexed: 06/08/2023]
Abstract
Two-stage dilute hydrochloric acid (DA)/aqueous ammonia wet oxidation (AWO) pretreatment was used to recover the sugars of corn stover. The morphology characterizations of samples were detected by SEM, BET and SXT. The results showed that DA-AWO process demonstrated a positive effect on sugar recovery compared to AWO-DA. 82.8% of xylan was recovered in the first stage of DA-AWO process at 120 °C for 40 min with 1 wt% HCl. The second stage was performed under relative mild reaction conditions (130 °C, 12.6 wt% ammonium hydroxide, 3.0 MPa O2, 40 min), and 86.1% lignin could be removed. 71.5% of glucan was achieved with a low enzyme dosage (3 FPU·g-1) in the following enzymatic hydrolysis. DA-AWO pretreatment was effective due to its sufficient hydrolysis of hemicellulose in the first stage and remarkably removal of the lignin in the second stage, resulting in high sugar recovery with a low enzyme dosage.
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Affiliation(s)
- Shengxin An
- Laboratory of Basic Research in Biomass Conversion and Utilization, University of Science and Technology of China, Hefei 230026, PR China; Institute of Chemical Engineering, Anhui University of Science and Technology, Huainan 232001, PR China
| | - Wenzhi Li
- Laboratory of Basic Research in Biomass Conversion and Utilization, University of Science and Technology of China, Hefei 230026, PR China; National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230026, PR China.
| | - Qiyu Liu
- Laboratory of Basic Research in Biomass Conversion and Utilization, University of Science and Technology of China, Hefei 230026, PR China
| | - Ying Xia
- Laboratory of Basic Research in Biomass Conversion and Utilization, University of Science and Technology of China, Hefei 230026, PR China; Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510650, PR China
| | - Tingwei Zhang
- Laboratory of Basic Research in Biomass Conversion and Utilization, University of Science and Technology of China, Hefei 230026, PR China
| | - Feng Huang
- Laboratory of Basic Research in Biomass Conversion and Utilization, University of Science and Technology of China, Hefei 230026, PR China
| | - Qizhao Lin
- Laboratory of Basic Research in Biomass Conversion and Utilization, University of Science and Technology of China, Hefei 230026, PR China
| | - Liang Chen
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230026, PR China
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Zhang H, Wei W, Zhang J, Huang S, Xie J. Enhancing enzymatic saccharification of sugarcane bagasse by combinatorial pretreatment and Tween 80. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:309. [PMID: 30455738 PMCID: PMC6225707 DOI: 10.1186/s13068-018-1313-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 11/01/2018] [Indexed: 05/09/2023]
Abstract
BACKGROUND The recalcitrant structure of lignocellulosic biomass made it challenging for their bioconversion into biofuels and biochemicals. Pretreatment was required to deconstruct the intact structure by the removal of hemicellulose/lignin, improving the cellulose accessibility of enzyme. Combinatorial pretreatments with liquid hot water/H2SO4 and ethanol/NaOH of sugarcane bagasse were developed to improve enzymatic hydrolysis under mild conditions. RESULTS After one-step 60% ethanol containing 0.5% NaOH pretreatment with solid to liquid ratio of 1/10, the glucose yield after hydrolysis for 72 h with enzyme dosage of 20 FPU/g substrate was enhanced by 41% and 205% compared to that of NaOH or 60% ethanol pretreated solids, respectively. This improvement was correlated with the removal of hemicellulose and lignin. However, using combinatorial pretreatments with 1% H2SO4 followed by 60% ethanol containing 0.5% NaOH, the highest glucose yield with Tween 80 reached 76%, representing 84.5% of theoretical glucose in pretreated substrate. While retaining similar glucose yield, the addition of Tween 80 capacitated either a reduction of enzyme loading by 50% or shortening hydrolysis time to 24 h. However, the enhancement with the addition of Tween 80 decreased as hydrolysis time was extended. CONCLUSIONS This study demonstrated that a combinatorial pretreatment with 1% H2SO4 followed by 60% ethanol containing 0.5% NaOH had significant effects on improving the enzymatic hydrolysis of sugarcane bagasse. The addition of Tween 80 enabled reducing the enzyme loading or shortening the hydrolysis time. This study provided an economically feasible and mild process for the generation of glucose, which will be subsequently converted to bioethanol and biochemicals.
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Affiliation(s)
- Hongdan Zhang
- College of Forestry and Landscape Architecture, Key Laboratory of Energy Plants Resource and Utilization, Ministry of Agriculture, South China Agricultural University, Guangzhou, 510642 People’s Republic of China
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, 510640 People’s Republic of China
| | - Weiqi Wei
- College of Light Industry and Food Engineering, Nanjing Forestry University, Nanjing, 210037 People’s Republic of China
| | - Jiajie Zhang
- College of Forestry and Landscape Architecture, Key Laboratory of Energy Plants Resource and Utilization, Ministry of Agriculture, South China Agricultural University, Guangzhou, 510642 People’s Republic of China
| | - Shihang Huang
- College of Forestry and Landscape Architecture, Key Laboratory of Energy Plants Resource and Utilization, Ministry of Agriculture, South China Agricultural University, Guangzhou, 510642 People’s Republic of China
| | - Jun Xie
- College of Forestry and Landscape Architecture, Key Laboratory of Energy Plants Resource and Utilization, Ministry of Agriculture, South China Agricultural University, Guangzhou, 510642 People’s Republic of China
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Evaluation of the overall process on bioethanol production from miscanthus hydrolysates obtained by dilute acid pretreatment. BIOTECHNOL BIOPROC E 2017. [DOI: 10.1007/s12257-016-0485-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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13
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Tang S, Liu R, Sun FF, Dong C, Wang R, Gao Z, Zhang Z, Xiao Z, Li C, Li H. Bioprocessing of tea oil fruit hull with acetic acid organosolv pretreatment in combination with alkaline H 2O 2. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:86. [PMID: 28405217 PMCID: PMC5385081 DOI: 10.1186/s13068-017-0777-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Accepted: 04/05/2017] [Indexed: 05/11/2023]
Abstract
BACKGROUND As a natural renewable biomass, the tea oil fruit hull (TOFH) mainly consists of lignocellulose, together with some bioactive substances. Our earlier work constructed a two-stage solvent-based process, including one aqueous ethanol organosolv extraction and an atmospheric glycerol organosolv (AGO) pretreatment, for bioprocessing of the TOFH into diverse bioproducts. However, the AGO pretreatment is not as selective as expected in removing the lignin from TOFH, resulting in the limited delignification and simultaneously high cellulose loss. RESULTS In this study, acetic acid organosolv (AAO) pretreatment was optimized with experimental design to fractionate the TOFH selectively. Alkaline hydrogen peroxide (AHP) pretreatment was used for further delignification. Results indicate that the AAO-AHP pretreatment had an extremely good selectivity at component fractionation, resulting in 92% delignification and 88% hemicellulose removal, with 87% cellulose retention. The pretreated substrate presented a remarkable enzymatic hydrolysis of 85% for 48 h at a low cellulase loading of 3 FPU/g dry mass. The hydrolyzability was correlated with the composition and structure of substrates by using scanning electron microscopy, confocal laser scanning microscopy, and X-ray diffraction. CONCLUSION The mild AAO-AHP pretreatment is an environmentally benign and advantageous scheme for biorefinery of the agroforestry biomass into value-added bioproducts.
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Affiliation(s)
- Song Tang
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122 China
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, 510640 China
| | - Rukuan Liu
- National Engineering Research Center for Oil-tea Camellia, Hunan Academy of Forestry, Changsha, 410004 China
| | - Fubao Fuelbiol Sun
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122 China
| | - Chunying Dong
- National Engineering Research Center for Oil-tea Camellia, Hunan Academy of Forestry, Changsha, 410004 China
| | - Rui Wang
- National Engineering Research Center for Oil-tea Camellia, Hunan Academy of Forestry, Changsha, 410004 China
| | - Zhongyuan Gao
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122 China
- Key Laboratory of Advanced Textile Materials and Manufacturing Technology, Ministry of Education, Zhejiang Sci-Tech University, Hangzhou, 310018 China
| | - Zhanying Zhang
- Centre for Tropical Crops and Biocommodities, Queensland University of Technology, Brisbane, QLD 4001 Australia
| | - Zhihong Xiao
- National Engineering Research Center for Oil-tea Camellia, Hunan Academy of Forestry, Changsha, 410004 China
| | - Changzhu Li
- National Engineering Research Center for Oil-tea Camellia, Hunan Academy of Forestry, Changsha, 410004 China
| | - Hui Li
- National Engineering Research Center for Oil-tea Camellia, Hunan Academy of Forestry, Changsha, 410004 China
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Qing Q, Guo Q, Zhou L, He Y, Wang L, Zhang Y. Enhancement of In Situ Enzymatic Saccharification of Corn Stover by a Stepwise Sodium Hydroxide and Organic Acid Pretreatment. Appl Biochem Biotechnol 2016; 181:350-364. [PMID: 27544773 DOI: 10.1007/s12010-016-2216-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2016] [Accepted: 08/12/2016] [Indexed: 10/21/2022]
Abstract
A stepwise pretreatment method that combines sodium hydroxide and organic acid pretreatments was proposed and investigated to maximize the recovery of main constituents of lignocellulose. The sodium hydroxide pretreatment was firstly optimized by a designed orthogonal experiment with the optimum pretreatment conditions determined as 1 wt% NaOH at 70 °C for 1 h, and 60.42 % of lignin was successfully removed during this stage. In the second stage, 0.5 % acetic acid was selected to pretreat the first-stage solid residue at 80 °C for 40 min in order to decompose hemicelluloses to soluble oligomers or monomers. Then, the whole slurry was subjected to in situ enzymatic saccharification by cellullase with a supplementation of xylanase to further degrade the xylooligosaccharides generated during the acetic acid pretreatment. The maximum reducing sugar and glucose yields achieved were 20.74 and 12.03 g/L, respectively. Furthermore, rapid ethanol fermentation and a yield of 80.3 % also testified this pretreatment method, and the in situ saccharification did not bring any negative impact on ethanol fermentation and has a broad application prospect.
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Affiliation(s)
- Qing Qing
- Department of Biochemical Engineering, College of Pharmaceutical Engineering and Life Science, Changzhou University, Changzhou, Jiangsu, 213164, China
| | - Qi Guo
- Department of Biochemical Engineering, College of Pharmaceutical Engineering and Life Science, Changzhou University, Changzhou, Jiangsu, 213164, China
| | - Linlin Zhou
- Department of Biochemical Engineering, College of Pharmaceutical Engineering and Life Science, Changzhou University, Changzhou, Jiangsu, 213164, China
| | - Yucai He
- Department of Biochemical Engineering, College of Pharmaceutical Engineering and Life Science, Changzhou University, Changzhou, Jiangsu, 213164, China
| | - Liqun Wang
- Department of Biochemical Engineering, College of Pharmaceutical Engineering and Life Science, Changzhou University, Changzhou, Jiangsu, 213164, China
| | - Yue Zhang
- Department of Biochemical Engineering, College of Pharmaceutical Engineering and Life Science, Changzhou University, Changzhou, Jiangsu, 213164, China.
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