Schäfer Judith, Sattler Melinda, Iqbal Yasir, Lewandowski Iris, Bunzel Mirko
Department of Food Chemistry and Phytochemistry, Institute of Applied Biosciences Karlsruhe Institute of Technology (KIT) Karlsruhe Germany.
Biobased Products and Energy Crops (340b), Institute of Crop Science University of Hohenheim Stuttgart Germany.
Glob Change Biol Bioenergy. 2019 Jan;11(1):191-205. doi: 10.1111/gcbb.12538. Epub 2018 Aug 13.
Efficient utilization of lignocellulosic biomass for the production of biochemicals, such as ethanol, is challenging due to its recalcitrance, which is influenced by the individual plant cell wall polymers and their interactions. Lignocellulosic biomass composition differs depending on several factors, such as plant age, harvest date, organ type, and genotype. Here, four selected genotypes (, , × , × hybrid) were grown and harvested, separated into stems and leaves, and characterized for their non-starch polysaccharide composition and structures, lignin contents and structures, and hydroxycinnamate profiles (monomers and ferulic acid dehydrodimers). Polysaccharides of all genotypes are mainly composed of cellulose and low-substituted arabinoxylans. Ratios of hemicelluloses to cellulose were comparable, with the exception of that showed a higher hemicellulose/cellulose ratio. Lignin contents of stems were higher than those of leaves. Considering the same organs, the four genotypes did not differ in their Klason lignin contents, but × showed the highest acetylbromide soluble lignin content. Lignin polymers isolated from stems varied in their S/G ratios and linkage type distributions across genotypes. -Coumaric acid was the most abundant ester-bound hydroxycinnamte monomer in all samples. Ferulic acid dehydrodimers were analyzed as cell wall cross-links, with 8-5-coupled diferulic acid being the main dimer, followed by 8-O-4-, and 5-5-diferulic acid. Contents of -coumaric acid, ferulic acid, and ferulic acid dimers varied depending on genotype and organ type. The largest amount of cell wall cross-links was analyzed for .
由于木质纤维素生物质具有顽固性，受单个植物细胞壁聚合物及其相互作用的影响，将其高效用于生产生物化学品（如乙醇）具有挑战性。木质纤维素生物质的组成因多种因素而异，如植物年龄、收获日期、器官类型和基因型。在此，种植并收获了四种选定的基因型（、、×、×杂交种），将其分为茎和叶，并对其非淀粉多糖组成和结构、木质素含量和结构以及羟基肉桂酸谱（单体和阿魏酸脱氢二聚体）进行了表征。所有基因型的多糖主要由纤维素和低取代阿拉伯木聚糖组成。半纤维素与纤维素的比例相当，但显示出较高的半纤维素/纤维素比例。茎的木质素含量高于叶。考虑到相同的器官，四种基因型的克拉森木质素含量没有差异，但×显示出最高的乙酰溴可溶性木质素含量。从茎中分离出的木质素聚合物在不同基因型之间的S/G比和连接类型分布有所不同。对香豆酸是所有样品中最丰富的酯结合羟基肉桂酸单体。阿魏酸脱氢二聚体作为细胞壁交联进行分析，8-5-偶联二阿魏酸是主要二聚体，其次是8-O-4-和5-5-二阿魏酸。对香豆酸、阿魏酸和阿魏酸二聚体的含量因基因型和器官类型而异。分析的细胞壁交联量最大。
