超高速利格宁从不寻常的地中海木质细胞残留物中提取
Summary
深乳酸溶剂基，微波辅助预处理是一个绿色，快速，高效的过程，为木质细胞分馏和高纯度木质素回收。
Abstract
预处理仍然是木质细胞学生物精炼过程中最昂贵的一步。它必须通过最大限度地减少化学需求、功率和热量消耗以及使用环保溶剂来实现成本效益。深乳酸盐溶剂 （DES） 是可持续生物定义中的关键、绿色和低成本溶剂。它们是透明混合物，其特点是至少由一个氢键供体和一个氢键接受者产生的低冰点。虽然 DES 是很有前途的溶剂，但有必要将其与经济加热技术（如微波辐照）相结合，以获得具有竞争力的盈利能力。微波辐照是缩短加热时间和提高分馏的一项很有前途的策略，因为它可以迅速达到适当的温度。本研究的目的是开发一种单步、快速的生物质分馏和木质素提取方法，使用低成本和可生物降解的溶剂。
在这项研究中，使用三种DES进行了60年代的微波辅助DES预处理，在800 W。DES混合物由胆碱氯化物（ChCl）和三个氢键捐赠者（HBDs）简单制备：单碳酸（乳酸）、二甲基糖酸（草酸）和尿素。这种预处理用于从海洋残留物（波西多尼亚叶和藻类）、农业食品副产品（杏仁壳和橄榄果）、森林残留物（松果）和常年木质细胞草（斯蒂帕特纳西西玛）中恢复生物质分馏和木质素。进一步分析以确定回收木质素的产量、纯度和分子重量分布。此外，DESs对提取木质素中的化学功能组的影响由富利埃转化红外（FTIR）光谱仪确定。结果表明，ChCl-草酸混合物具有最高的木质素纯度和最低的产量。本研究表明，DES微波工艺是一种超高速、高效且具有成本竞争力的木质细胞生物质分馏技术。
Introduction
可持续的生物精炼过程将生物质加工、其分馏成感兴趣的分子，并转化为增值产品1。在第二代生物修复中，预处理被认为是将生物质分成主要成分2的必要条件。利用化学、物理或生物策略的传统预处理方法已得到广泛应用。然而，这种预处理被认为是生物修复中最昂贵的一步，并具有其他缺点，如加工时间长，热和功耗高，溶剂杂质4。最近，DESs的特性与离子液体3相似，由于生物降解性、环保性、易合成性、治疗后恢复等优点，成为绿色溶剂。
DES 是至少一种 HBD 的混合物，如乳酸、粘液酸或草酸，以及氢键接受剂 （HBA） 的混合物，如贝坦或氯化胆 （ChCl）6。HBA-HBD 相互作用使催化机制能够使化学键裂开，导致生物质分裂和木质素分离。许多研究人员已经报告了基于DES的木质细胞素原料的预处理，如玉米棒上的ChCl-甘油和7号、8号、ChCl-尿素、 小麦稻草上的ChCl-草酸9，桉树锯末上的ChCl-乳酸10，木材上的ChCl-醋酸11和木上的ChCl-乙烯乙二醇。为了提高DES效率，预处理应与微波处理相结合，以加速生物质分馏5。许多研究人员报告了这种对8号木和玉米茎、开关草和米斯坎图斯5号的联合预处理（DES和微波），这为在短时间内对DES在木质细胞分馏和木质素提取方面的能力提供了新的见解。
木质素是一种酚类巨分子，作为生物聚合物生产的原料，是芳香单体和寡聚物等化学物质生产的替代品。此外，木质素具有抗氧化和紫外线吸收活动13。一些研究已经报告了木质素在化妆品中的应用14，15。其在商业防晒产品的集成改善了产品的防晒系数（SPF）从SPF 15到SPF 30，只增加了2 wt % 的木质素和高达SPF 50，增加了10瓦特%的木质素16。本文描述了一种超快的木质素 – 碳水化合物方法，辅之以地中海生物量的 DES – 微波预处理。这些生物量由农业食品副产品组成，特别是橄榄豆和杏仁壳。被调查的其他生物量是海洋原产物（波西多尼亚叶和海生物）和源自森林的生物量（松果和野生草）。本研究的重点是测试低成本的绿色溶剂，以评估这种联合预处理对原料分馏的影响，调查其对木质素纯度和产量的影响，并研究其对提取木质素中的分子量和化学功能组的影响。
Protocol
Representative Results
Discussion
这项研究有许多目标：首先是准备和使用具有离子液体和有机溶剂特性的低成本绿色溶剂。第二个目标是将生物量分成一步，提取木质素，而不需要初步步骤，例如使用碱性溶剂、基本或热物理技术使用 Soxhlet 或半纤维素提取可提取物。第三个目标是在治疗后通过简单的过滤来恢复木质素，无需调整pH度，而只需加入蒸馏水即可。使用微波辅助的基于 DES 的工艺从六种不同来源超高速提取木质素的…
Declarações
The authors have nothing to disclose.
Acknowledgements
MK 和 TB 感谢海瑟姆 ·阿耶布的统计分析和数字准备，瓦隆地区（欧洲区域发展-VERDIR）和高等教育和科学研究部长（陶菲克·贝塔伊布）提供资金。
Materials
| HPLC Gel Permeation Chromatography | Agilent 1200 series | ||
| 1 methylimadazole | Acros organics | ||
| 2-deoxy-D-glucose (internal standard) | Sigma Aldrich (St. Louis, USA) | ||
| Acetic acid | Sigma Aldrich (St. Louis, USA) | ||
| Acetic anhydride | Sigma Aldrich (St. Louis, USA) | ||
| Adjustables pipettors | |||
| Alkali | alkali-extracted lignin | ||
| Arabinose (99%) | Sigma Aldrich (St. Louis, USA) | ||
| Autoclave | CERTO CLAV (Model CV-22-VAC-Pro) | ||
| Water Bath at 70 °C | |||
| Boric acid | Sigma Aldrich (St. Louis, USA) | ||
| Bromocresol | Sigma Aldrich (St. Louis, USA) | ||
| Catalyst | CTQ (coded A22) (1.5 g K2SO4 + 0.045 g CuSO4.5 H2O + 0.045 g TiO2) | Merck | |
| Centrifugation container | |||
| Centrifuge | BECKMAN COULTER | Avanti J-E centrifuge | |
| Ceramic crucibles | |||
| Choline chloride 99% | Acros organics | ||
| Column | Agilent PLGel Mixed C (alpha 3,000 (4.6 × 250 mm, 5 µm) preceded by a guard column (TSK gel alpha guard column 4.6 mm × 50 mm, 5 µm) | ||
| Column | HP1-methylsisoxane (30 m, 0.32 mm, 0.25 mm) | ||
| Crucible porosity N°4 ( Filtering crucible) | Shott Duran Germany | boro 3.3 | |
| Deonized water | |||
| Dessicator | |||
| Dimethylformamide | VWR BDH Chemicals | ||
| Dimethylsulfoxide | Acros organics | ||
| Erlenmeyer flask | |||
| Ethanol | Merck (Darmstadtt, Germany) | ||
| Filtering crucibles, procelain | |||
| Filtration flasks | |||
| Fourrier Transformed Inra- Red | Vertex 70 Bruker apparatus equipped with an attenuated total reflectance (ATR) module. Spectra were recorded in the 4,000–400 cm−1 range with 32 scans at a resolution of 4.0 cm−1 |
||
| Galactose (98% | Sigma Aldrich (St. Louis, USA) | ||
| Gaz Chromatography | Agilent (7890 series) | ||
| Glass bottle 100 mL | |||
| Glass tubes ( borosilicate) with teflon caps 10 mL | |||
| Glucose (98% | Sigma Aldrich (St. Louis, USA) | ||
| Golves | |||
| Graduated cylinder 50 mL /100 mL | |||
| H2SO4 Titrisol (0.1 N) | Merck (Darmstadtt, Germany) | ||
| H2SO4 (95-98%) | Sigma Aldrich (St. Louis, USA) | BUCHI R-114) | |
| Hummer cutter equiped with 1 mm and 0.5 mm sieve | Mill Ttecator (Sweden) | Cyclotec 1093 | |
| Indulin | Raw lignin control | ||
| Kjeldahl distiller | Kjeltec 2300 (Foss) | ||
| Kjeldahl tube | FOSS | ||
| Kjeldhal rack | |||
| Kjeldhal digester | Kjeltec 2300 (Foss) | ||
| Kjeldhal suction system | |||
| Lab Chem station Software | GC data analysis | ||
| Lactic acid | Merck (Darmstadtt, Germany) | ||
| Lithium chloride LiCl | Sigma Aldrich (St. Louis, USA) | ||
| Mannose (98%) | Sigma Aldrich (St. Louis, USA) | ||
| Methyl red | |||
| Microwave | START SYNTH MILESTONE Microwave laboratory system | ||
| Microwave temperature probe | |||
| Microwave container | |||
| Muffle Furnace | |||
| NaOH | Merck (Darmstadtt, Germany) | ||
| Nitrogen free- paper | |||
| Opus | spectroscopy software | ||
| Oven | GmbH Memmert SNB100 | Memmert SNB100 | |
| Oxalic acid | VWR BDH Chemicals | ||
| P 1000 | Soda-processed lignin | ||
| pH paper | |||
| precision balance | |||
| Infrared spectroscopy | |||
| Quatz cuvette | |||
| Rhamnose (98%) | Sigma Aldrich (St. Louis, USA) | ||
| Rotary vacuum evaporator | Bucher | ||
| Round-bottom flask 500 mL | |||
| sodium borohydride NaBH4 | |||
| Schott bottle | glass bottle | ||
| Sovirel tubes | sovirel | Borosilicate glass tubes | |
| Spatule | |||
| Special tube | |||
| Spectophotometer | UV-1800 Shimadzu | ||
| Sterilization indicator tape | |||
| Stir bar in teflon | |||
| Stirring plate | |||
| Syringes | |||
| Sodium borohydride | Sigma Aldrich (St. Louis, USA) | ||
| Titrisol | Merck | Merck 109984 | 0.1 N H2SO4 |
| Urea | VWR BDH Chemicals | ||
| Vials | |||
| VolumetriC flask 2.5 L /5 L | Bucher | ||
| Vortex | |||
| Xylose (98%) | Sigma Aldrich (St. Louis, USA) |
Referências
- Kammoun, M., et al. Hydrothermal dehydration of monosaccharides promoted by seawater fundamentals on the catalytic role of inorganic salts. Frontiers in Chemistry. 7, 132 (2019).
- Kammoun, M., Ayeb, H., Bettaieb, T., Richel, A. Chemical characterisation and technical assessment of agri-food residues, marine matrices, and wild grasses in the South Mediterranean area: A considerable inflow for biorefineries. Waste Management. 118, 247-257 (2020).
- Zhang, C. W., Xia, S. Q., Ma, P. Facile pretreatment of lignocellulosic biomass using deep eutectic solvents. Bioresource Technology. 219, 1-5 (2016).
- Mora-Pale, M., Meli, L., Doherty, T. V., Linhardt, R. J., Dordick, J. S. Room temperature ionic liquids as emerging solvents for the pretreatment of lignocellulosic biomass. Biotechnology and Bioengineering. 108 (6), 1229-1245 (2011).
- Chen, Z., Wan, C. Ultrafast fractionation of lignocellulosic biomass by microwave-assisted deep eutectic solvent pretreatment. Bioresource Technologie. 250, 532-537 (2018).
- Francisco, M., Van Den Bruinhorst, A., Kroon, M. C. New natural and renewable low transition temperature mixtures ( LTTMs ): screening as solvents for lignocellulosic biomass processing. Green Chemistry. 14 (8), 2153-2157 (2012).
- Liu, Y. C., et al. Efficient cleavage of lignin – carbohydrate complexes and ultrafast extraction of lignin oligomers from wood biomass by microwave-assisted treatment with deep eutectic solvent. Chem sus chem. 10, 1692-1700 (2017).
- Xu, G. C., Ding, J. C., Han, R. Z., Dong, J. J., Ni, Y. Enhancing cellulose accessibility of corn stover by deep eutectic solvent pretreatment for butanol fermentation. Bioresource Technologie. 203, 364-369 (2016).
- Jablonský, M., Andrea, &. #. 3. 5. 2. ;., Kamenská, L., Vrška, M., Šima, J. Deep eutectic solvents fractionation of wheat straw deep eutectic solvents fractionation of wheat straw. Bioresources. 10 (4), 8039-8047 (2015).
- Shen, X. J., et al. Facile fractionation of lignocelluloses by biomass-derived deep eutectic solvent (DES) pretreatment for cellulose enzymatic hydrolysis and lignin valorization. Green Chemistry. 21, 275-283 (2019).
- Alvarez-Vasco, C., et al. Unique low-molecular-weight lignin with high purity extracted from wood by deep eutectic solvents (DES): a source of lignin for valorization. Green Chemistry. 18, 5133-5141 (2016).
- Banu, J. R., et al. A review on biopolymer production via lignin valorization. Bioresource Technologie. 290, 121790 (2019).
- Gordobil, O., Olaizola, P., Banales, J. M., Labidi, J. Lignins from agroindustrial by-products as natural ingredients for cosmetics chemical structure and in vitro sunscreen and cytotoxic activities. Molecules. 25 (5), 1131 (2020).
- Lee, C. S., Thu Tran, T. M., Weon Choi, J., Won, K. Lignin for white natural sunscreens. International Journal of Biological Macromolecules. 122, 549-554 (2019).
- Widsten, P. Lignin-based sunscreens-state-of-the-art, prospects and challenges. Cosmetics. 7, 85 (2020).
- Qian, Y., Qiu, X., Zhu, S. Lignin: a nature-inspired sun blocker for broad-spectrum sunscreens. Royal Society of Chemistry. 17, 320-324 (2015).
- Zijlstra, D. S., et al. Extraction of lignin with high β-O-4 content by mild ethanol extraction and its effect on the depolymerization yield. Journal of Visualized Experiments. (143), e58575 (2019).
