Abstract: In this study, non-targeted metabolomics method based on ultra-high performance liquid chromatography q exactive mass spectrometry (UHPLC-QE-MS) was used to explore the change in metabolite profile in Bactrian camel meat from different age groups. The results showed that a total of 710 differentially expressed metabolites (DEMs) were identified in the longissimus dorsi muscle of camel meat from three age groups (3~4 years, 6~7 years, and 9~10 years; represented by I, II, and III, respectively); The number of DEMs was 78 in the I vs II comparison group, of which 47 were upregulated in group I and 31 were upregulated in group II; there were 49 DEMs in the II vs. III comparison group, of which 18 were upregulated in the II group and 31 were upregulated in the III group; in the same way, there were 65 DEMs in the I vs III comparison group, with 29 upregulated in group I and 36 upregulated in group III. The KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway analysis results showed that DEMs were mainly enriched in related pathways such as protein and amino acid metabolism, fatty acid metabolism, vitamin and mineral metabolism, indicating that the digestion and metabolism of various nutrients in camels at different growth stages were different. The content of polyunsaturated fatty acids (especially n-6 PUFA, n-3 PUFA) and the ratio of PUFA/UFA (Polyunsaturated fatty acid，PUFA；Unsaturated fatty acid, UFA) in group I were significantly higher than those in group III, which was mainly related to the significant increase of arachidonic acid, linoleic acid and 13-L-hydroperooleic acid concentrations in the related metabolic pathways; meanwhile, DEMs such as L-leucine, L-valine, and L-glutamine could be used as potential markers for evaluating the quality change of camel meat from different ages. The results of this study provide a theoretical basis for understanding postmortem metabolism in camel muscle and for quality control of camel meat from different ages.

Key words: Bactrian camel meat, different ages, non-targeted metabolomics, metabolites, metabolic pathway