Department of Forest Products Technology, School of Science and Technology, Aalto University, P.O. Box 16300, 00076 Aalto, Finland.
Phytochemistry. 2011 Oct;72(14-15):1889-95. doi: 10.1016/j.phytochem.2011.05.005. Epub 2011 May 31.
Wood cell wall consists of several structural components, such as cellulose, hemicelluloses and lignin, whose concentrations vary throughout the cell wall. It is a composite where semicrystalline cellulose fibrils, acting as reinforcement, are bound together by amorphous hemicelluloses and lignin matrix. Understanding the distribution of these components and their functions within the cell wall can provide useful information on the biosynthesis of trees. Raman imaging enables us to study chemistry of cell wall without altering the structure by staining the sample or fractionating it. Raman imaging has been used to analyze distributions of lignin and cellulose, as well as the functional groups of lignin in wood. In our study, we observed the distribution of cellulose and lignin, as well as the amount of coniferyl alcohol and aldehyde groups compared to the total amount of lignin in pine (Pinus sylvestris) and spruce (Picea abies) wood samples. No significant differences could be seen in lignin and cellulose distribution between these samples, while clear distinction was observed in the distribution of coniferyl alcohols and coniferyl aldehyde in them. These results could provide valuable insight on how two similar wood species control biosynthesis of lignin differently during the differentiation of cell wall.
木材细胞壁由几种结构成分组成，如纤维素、半纤维素和木质素，它们在细胞壁中的浓度不同。它是一种复合材料，其中半晶态纤维素原纤维作为增强剂，与无定形半纤维素和木质素基质结合在一起。了解这些成分在细胞壁内的分布及其功能，可以为树木的生物合成提供有用的信息。拉曼成像是一种无需对样品进行染色或分级即可研究细胞壁化学的方法。拉曼成像已被用于分析木质素和纤维素的分布，以及木材中木质素的功能基团。在我们的研究中，我们观察了纤维素和木质素的分布，以及与松木（Pinus sylvestris）和云杉（Picea abies）木材样品中总木质素相比，松柏醇和醛基的含量。在这些样品中，木质素和纤维素的分布没有明显差异，而松柏醇和松柏醛的分布则有明显区别。这些结果可以提供有价值的见解，了解两种相似的木材物种如何在细胞壁分化过程中控制木质素的生物合成。
