Barnes William J, Anderson Charles T
Department of Biology, The Pennsylvania State University, University Park, PA, USA.
Center for Lignocellulose Structure and Formation, The Pennsylvania State University, University Park, PA, USA.
Bio Protoc. 2017 Mar 5;7(5):e2149. doi: 10.21769/BioProtoc.2149.
Lignin is the second most abundant biopolymer on Earth, providing plants with mechanical support in secondary cell walls and defense against abiotic and biotic stresses. However, lignin also acts as a barrier to biomass saccharification for biofuel generation (Carroll and Somerville, 2009; Zhao and Dixon, 2011; Wang , 2013 ). For these reasons, studying the properties of lignin is of great interest to researchers in agriculture and bioenergy fields. This protocol describes the acetyl bromide method of total lignin extraction and quantification, which is favored among other methods for its high recovery, consistency, and insensitivity to different tissue types ( Johnson , 1961 ; Chang , 2008 ; Moreira- Vilar , 2014 ; Kapp , 2015 ). In brief, acetyl bromide digestion causes the formation of acetyl derivatives on free hydroxyl groups and bromide substitution of α-carbon hydroxyl groups on the lignin backbone to cause a complete solubilization of lignin, which can be quantified using known extinction coefficients and absorbance at 280 nm (Moreira- Vilar , 2014 ).
木质素是地球上第二丰富的生物聚合物，为植物的次生细胞壁提供机械支撑，并抵御非生物和生物胁迫。然而，木质素也是生物质糖化生产生物燃料的障碍（卡罗尔和萨默维尔，2009年；赵和迪克森，2011年；王，2013年）。基于这些原因，研究木质素的特性引起了农业和生物能源领域研究人员的极大兴趣。本方案描述了总木质素提取和定量的乙酰溴法，该方法因其高回收率、一致性以及对不同组织类型不敏感而在其他方法中受到青睐（约翰逊，1961年；张，2008年；莫雷拉 - 比拉尔，2014年；卡普，2015年）。简而言之，乙酰溴消化会导致游离羟基上形成乙酰衍生物，以及木质素主链上α - 碳羟基的溴取代，从而使木质素完全溶解，可使用已知的消光系数和280 nm处的吸光度进行定量（莫雷拉 - 比拉尔，2014年）。
