Abstract: The metabolites in two different varieties of foxtail millets from the same geographical origin were studied by metabonomics based on gas chromatography-mass spectrometry (GC-MS). The polar metabolites were extracted using methanol solution and then derivatized with N,O-bis(trimethylsilyl)trifluoroacetamide prior to analysis by GC-MS. The results showed that a total of 53 metabolites were identified, 48 of which were found in ‘Gulong’ millet, the dominant ones being linoleic acid and 2-linolacyl-rac-glycerol; and 32 in ‘Heshen’ millet, the dominant ones being linoleic acid and glycerol. There were 21 differential metabolites identified in ‘Gulong’ millet and five differential metabolites in ‘Heshen’ millet. The metabolic pathways of the differential metabolites were also studied. It was found that the glucose, fatty acid, amino acid metabolism pathways and the tricarboxylic acid cycle in ‘Gulong’ millet were more active than those in Hesen millet. It was speculated that the increase in the number of metabolites in ‘Gulong’ millet may be because its metabolic rate was faster than that of ‘Heshen’ millet.

Key words: millet; metabolites; gas chromatography-mass spectrometry; metabonomics; different varieties