Metabolite profiling of foxtail millet varieties from Qingyang using GC-MS and LC-MS analysis

Area of Science:

• Agricultural Science
• Metabolomics
• Food Chemistry

Background:

• Foxtail millet (Setaria italica) has a long cultivation history in Gansu Province, with diverse cultivars.
• Metabolic variations among these foxtail millet cultivars are not well understood.
• Understanding cultivar-specific metabolism is crucial for optimizing foxtail millet utilization.

Purpose of the Study:

• To comprehensively analyze and compare the volatile and non-volatile metabolomes of five distinct foxtail millet cultivars.
• To identify key metabolites contributing to flavor and nutritional profiles.
• To provide a metabolic basis for foxtail millet processing and quality control.

Main Methods:

• Gas Chromatography-Mass Spectrometry (GC-MS) for volatile compound analysis.
• Liquid Chromatography-Mass Spectrometry (LC-MS) for non-volatile metabolite profiling.
• Database comparisons (Human Metabolome Database - HMDB) and pathway analysis (Kyoto Encyclopedia of Genes and Genomes - KEGG).

Main Results:

• Detected 64 volatile compounds via GC-MS, with aldehydes identified as primary flavor contributors.
• Identified 1512 non-volatile metabolites via LC-MS.
• Observed distinct metabolic profiles: cultivars JG21, ZZ13, and JF107 showed high proportions of lipids, while HM and JG1 were rich in organic acids. Sixteen differential polyphenols, including flavonoids like apigenin and luteolin, were identified with their biosynthetic pathways elucidated.

Conclusions:

• Significant metabolic differences exist among foxtail millet cultivars, particularly in lipid and organic acid content.
• Volatile aldehydes are key to foxtail millet's characteristic flavor.
• The identified polyphenols and their pathways offer insights for breeding and product development, aiding downstream processing and quality control.