Optimization of biomass pretreatments using fractional factorial experimental design.
Optimization of biomass pretreatments using fractional factorial experimental design.
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DOI：
10.1186/s13068-018-1200-2
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发表时间：
2018
影响因子：
6.3
通讯作者：
McQueen-Mason SJ
中科院分区：
文献类型：
--
作者：
Rezende CA;Atta BW;Breitkreitz MC;Simister R;Gomez LD;McQueen-Mason SJ
预处理是木质纤维素转化过程的主要瓶颈之一，并且为每种生物质寻找更便宜且有效的预处理方法是一项复杂但基本的任务。在这里，我们使用2ν5−1部分因子设计（FFD）来优化五个预处理变量：研磨时间，温度，双重处理，化学浓度，以及酸-碱（EA）和酸-有机溶剂（EO）预处理的预处理时间，应用于象草叶。FFD允许优化的预处理条件，使用减少的实验数量，并允许识别的因素之间的次要相互作用。FFD表明，温度可以保持在其较低的水平，第一个酸步骤可以在两个预处理中消除，没有显着的损失酶水解。在碱步骤中使用以下条件，EA导致还原糖的最高释放（最大205 mg/g底物，相比之下，EO中为152 mg/g，未处理样品中为40 mg/g）：[NaOH] = 4.5%w/v; 85 ℃，球磨样品后100 min。EA预处理中统计学显著（P < 0.05）的因素是NaOH浓度，其有助于通过木质素和二氧化硅去除来改善水解，以及研磨时间，其具有机械效应。对于EO样品，改善水解的统计学显著因素是乙醇和催化剂浓度，这两者都与预处理基材中较高的纤维素含量相关。催化剂也与木质素去除相关。预处理后的固体中的主要半纤维素糖的详细表征揭示了它们的独特的半柠檬性：葡萄糖通常比木糖和阿拉伯糖更半柠檬性，在特定的预处理下几乎可以完全去除。在EA样品中，半纤维素衍生物的去除非常依赖于酸步骤，特别是阿拉伯糖的去除。本文提出的结果有助于开发更有效和可行的预处理，以从草生物质生产纤维素乙醇，节省时间，成本和能源。它们还通过在每个加工步骤产生的固体中建立关键的柠檬酸聚合物，促进酶混合物的设计和预处理液中所含糖的更适当使用。本文的在线版本（10.1186/s13068-018-1200-2）包含补充材料，可供授权用户使用。
Pretreatments are one of the main bottlenecks for the lignocellulose conversion process and the search for cheaper and effective pretreatment methodologies for each biomass is a complex but fundamental task. Here, we used a 2ν5−1 fractional factorial design (FFD) to optimize five pretreatment variables: milling time, temperature, double treatment, chemical concentration, and pretreatment time in acid–alkali (EA) and acid–organosolv (EO) pretreatments, applied to elephant grass leaves. FFD allowed optimization of the pretreatment conditions using a reduced number of experiments and allowed the identification of secondary interactions between the factors. FFD showed that the temperature can be kept at its lower level and that the first acid step can be eliminated in both pretreatments, without significant losses to enzymatic hydrolysis. EA resulted in the highest release of reducing sugars (maximum of 205 mg/g substrate in comparison to 152 mg/g in EO and 40 mg/g in the untreated sample), using the following conditions in the alkali step: [NaOH] = 4.5% w/v; 85 °C and 100 min after ball milling the sample. The factors statistically significant (P < 0.05) in EA pretreatment were NaOH concentration, which contributes to improved hydrolysis by lignin and silica removal, and the milling time, which has a mechanical effect. For EO samples, the statistically significant factors to improved hydrolysis were ethanol and catalyst concentrations, which are both correlated to higher cellulose amounts in the pretreated substrates. The catalyst is also correlated to lignin removal. The detailed characterization of the main hemicellulosic sugars in the solids after pretreatments revealed their distinct recalcitrance: glucose was typically more recalcitrant than xylose and arabinose, which could be almost completely removed under specific pretreatments. In EA samples, the removal of hemicellulose derivatives was very dependent on the acid step, especially arabinose removal. The results presented herewith contribute to the development of more efficient and viable pretreatments to produce cellulosic ethanol from grass biomasses, saving time, costs and energy. They also facilitate the design of enzymatic cocktails and a more appropriate use of the sugars contained in the pretreatment liquors, by establishing the key recalcitrant polymers in the solids resulting from each processing step. The online version of this article (10.1186/s13068-018-1200-2) contains supplementary material, which is available to authorized users.
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影响因子：
6.3
作者：
Lima MA;Gomez LD;Steele-King CG;Simister R;Bernardinelli OD;Carvalho MA;Rezende CA;Labate CA;Deazevedo ER;McQueen-Mason SJ;Polikarpov I
通讯作者：
Polikarpov I
影响因子：
6.3
作者：
Tsuchida JE;Rezende CA;de Oliveira-Silva R;Lima MA;d'Eurydice MN;Polikarpov I;Bonagamba TJ
通讯作者：
Bonagamba TJ
影响因子：
7.4
作者：
Rabelo, Sarita C.;Andrade, Rafael R.;Costa, Aline C.
通讯作者：
Costa, Aline C.
影响因子：
10.4
作者：
Menegol, Daiane;Scholl, Angelica Luisi;Camassola, Marli
通讯作者：
Camassola, Marli
影响因子：
2.9
作者：
Anthon, GE;Barrett, DM
通讯作者：
Barrett, DM