Validation of PyMBMS as a High-throughput Screen for Lignin Abundance in Lignocellulosic Biomass of Grasses

Pyrolysis molecular-beam mass spectrometry (PyMBMS) was tested as a high-throughput method for relative abundances of guaiacyl and syringyl lignin in lignocellulosic cell-wall materials from stems of a population of maize intermated B73 x Mo17 (IBM) recombinant inbred lines. Variations of up to twofold across the population in phenylpropanoid abundance were observed. Several histochemical and quantitative biochemical assays were used to validate the mass spectrometric data for lignin, hydroxycinnamic acids, crystalline cellulose, non-cellulosic glucans, and xylans. We demonstrate PyMBMS to be a valid high-throughput screen suitable for analysis of lignin abundance in large populations of bioenergy grasses. Pentose from xylans and hexose from cellulosic and non-cellulosic glucans also varied substantially across the population, but abundances of diagnostic fragments for these monosaccharides were not well correlated with the abundance of cell-wall polysaccharides.