PYROLYSIS-GAS CHROMATOGRAPHY MASS-SPECTROMETRY OF LIGNOCELLULOSICS IN FORAGES AND BY-PRODUCTS

Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) was performed on 14 forages and by-products treated with sodium chlorite (NaClO2), vegetative wheat plant collected over the course of a growing season and lignins extracted with dioxane/water (C4H8O2/H2O), NaOH, aqueous HCl and HF, and H2SO4 from alfalfa stem, corn stalk, red oak leaf and wheat straw. The fingerprinting of the various feeds is discussed on the basis of a semi-quantitative analysis of the pyrograms, which also depicted a large decrease in aromatic products and the presence of chlorinated phenolics after treatment with NaClO2. Chemical analyses, however, indicated large amounts of lignin to still be present. Py-GC/MS analysis of isolated lignins showed significant differences among isolation methods and indicated a significant interaction with lignin source. Results also indicated that pyrolysis products of maturing wheat straw could be useful as markers of the lignification process during growth.