Profiling the chemical composition and growth strain of giant bamboo (Dendrocalamus giganteus Munro)

Abstract

The chemical composition of the wax layer and green epidermis at the surface of giant bamboo (Dendrocalamus giganteus Munro) culms were conveniently analyzed through the diffuse reflectance infrared Fourier transform (DRIFT) with Si-Carb sampling technique. Results from the radial lignin content profiling of giant bamboo showed that the lignin content in the middle layer was lower than the layers either from the inner or outer culms. As for the longitudinal depth profiling, the lignin contents of bamboo culms increased gradually from the top toward base portion. The distribution of growth strains in the radial direction of giant bamboo culm was investigated by the kerf method with strain gauges. The longitudinal tensile strains in various positions of giant bamboo culm were found to decrease in the order of the middle layer, the outer layer, and the inner layer. The tensile strains of different layers in the radial direction of giant bamboo culm correlate with their lignin content. The highest tensile strain on the middle layer of the bamboo culm was associated with the lowest lignin content. These results provided experimental evidence in the relationship between longitudinal tensile strain and lignin content of bamboo culm.