Study On Pyrolysis Of Some Isotope-Labiling Nature Products

Pyrolysis-gas chromatography/mass spectrometry(Py-GC/MS) is a common approach to studying pyrolysis of substance, biomass and tobacco at home and abroad. Py-GC/MS is used on studying pyrolysis mechanism of some compounds. Combining isotope tracer technique with Py-GC/MS, we can explore the pyrolysis mechanism of the traced compounds and acquire the fragments transferring path, etc. by comparing pyrolysis data of stable isotope labelled compound and unlabeled compound.We determined the pyrolysis temperature on the basis of thermogravimetric analysis curve. Conditions of gas chromatography: Heat up to 50 ℃ and retain for 3 min; Heat up at the rate of 5 ℃/min to 280 ℃ and retain for 10 min. Scanning time of the mass spectrometry is 1.5-40 min.We studied the pyrolysis of sugars, amino acids, acids and scopoletin respectively at different temperatures. The main pyrolysis product of D-fructose is furfural. The main pyrolysis product of D-glucose is not certain. Amino acids’ main pyrolysis products are furan and pyrrole derivatives. Butanedioic acid and malic acid’s main pyrolysis product is anhydride derivatives. When scopoletin pyrolyzed, about 90% of it transferred directly while about 10% pyrolyzed.We researched two compounds mixture pyrolysis. We researched the pyrolysis of D-fructose and L-glutamic acid, D-fructose and L-aspartic acid, D-fructose and L-proline, D-fructose and L-glutamine, D-fructose and L-asparagine. D-fructose and amino acids pyrolyzed producing a number of micromolecule compound(acetic acid, crylic acid, etc.). D-fructose’s main pyrolysis product is furfural. In two compounds mixture pyrolysis, abundance of furfural in pyrolysis product decrease obviously. Except for L-proline, other amino acids promote to produce 6-methyl-2,3-dihydrogen-3,5-dihydroxy-4H-furan-4-one. D-fructose and L-proline’s main pyrolysis product is pyrrole derivatives.Study on natural product pyrolysis by isotope tracer provided us with experimental bases for understanding Maillard reaction deeply and analysis bases for mechanism in pyrolysis.