Investigation of the plant cell wall's molecular structure models using the finite element modeling

Interests in the plant cell wall have been growing, since it is where plants produce and store polysaccharides that can be utilized as the bio-based energy resources. To take full advantage of the plant cell wall, knowledge of its detailed structure is essential. Plant cell wall's ability to expand during the growth phase has been explained by hypothesized molecular structures focusing on interactions between major polysaccharides. Typical example of such an attempt is the sticky network model which suggests that relatively slender hemicelluloses are tethering cellulose microfibrils with hydrogen bonds to bear stresses induced by turgor pressure. The various mechanisms of relaxing this conjectured model to allow expansion of the cell wall explanation have been proposed including disruptions of the hydrogen bonds to loosen the cell wall. A finite element analysis was successfully used to simulate a proposed molecular structure model to examine its consequences from the perspective of mechanics, i.e., hydrogen bonded hemicellulose alone cannot provide enough strength for the cell wall to maintain its integrity under a typical turgor pressure. As a next step, the hypothesized cell wall loosening mechanisms are being investigated to examine its mechanical validity and efficiency. This study showcases an engineering approach contributing to the fundamental science that can potentially impact the field of biorenewable energy.