基于UPLC-MS非靶向代谢组学分析不同年龄双峰驼肉代谢物差异

Analysis of Differential Muscle Metabolites in Bactrian Camels Slaughtered at Different Ages by Non-Targeted Metabolomics Based on Ultra-high Performance Liquid Chromatography-Mass Spectrometry

基于超高效液相色谱-质谱联用的非靶向代谢组学方法探究不同年龄组驼肉代谢物的差异及变化规律。结果表明,在3个年龄组(3~4、6~7岁和9~10岁,分别以I、II和III组表示)骆驼背最长肌中共鉴定出显著差异代谢物710种;在I vs II组显著差异代谢物有78个,其中I组上调47个,II组上调31个;在II vs III组显著差异代谢物有49个,其中II组上调18个,III组上调31个;在I vs III组显著差异代谢物有65个,其中I组上调29个,III组上调36个。京都基因与基因组百科全书通路分析结果表明,差异代谢物主要富集到蛋白质和氨基酸代谢、脂肪酸、维生素和矿物质代谢等相关通路,说明不同生长阶段骆驼中各营养素的消化代谢均有差异。I组中的多不饱和脂肪酸(polyunsaturated fatty acid,PUFA)(尤其n-6 PUFA、n-3 PUFA)含量和PUFA/不饱和脂肪酸值均显著高于III组,这主要与相关代谢通路上的花生四烯酸、亚油酸和13-L-过氧化氢油酸浓度的显著上调有关;同时L-亮氨酸、L-缬氨酸、L-谷氨酰胺等差异代谢物可以作为不同年龄驼肉品质差异的潜在标记物。

In this study,non-targeted metabolomics based on ultra-high performance liquid chromatography Q-Exactive-mass spectrometry(UPLC-Q-Exactive-MS)was used to explore the differences in the metabolite profiles of muscles from Bactrian camels slaughtered at different ages.The results showed that a total of 710 differentially expressed metabolites(DEMs)were identified in the longissimus dorsi muscle of camels from three age groups:I(3–4 years old),II(6–7 years old),and III(9–10 years old).In total,78 DEMs were found in groups I vs II,of which 47 were upregulated in group I and 31 were upregulated in group II.Totally,49 DEMs were identified in groups II vs III,of which 18 were upregulated in group II and 31 were upregulated in group III.In addition,65 DEMs were identified in groups I vs III,of which 29 were upregulated in group I and 36 were upregulated in group III.The results of Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analysis showed that the DEMs were mainly enriched in pathways such as protein and amino acid metabolism,fatty acid metabolism,and vitamin and mineral metabolism,indicating that the digestion and metabolism of various nutrients in camels were different at different growth stages.The contents of polyunsaturated fatty acids(PUFA)(especially n-6 PUFA and n-3 PUFA)and the PUFA/unsaturated fatty acid(UFA)ratio were significantly higher in group I than III,which was mainly related to the significant upregulation of arachidonic acid,linoleic acid and 13-L-hydroperooleic acid concentrations in relevant metabolic pathways.Meanwhile,DEMs such as L-leucine,L-valine,and L-glutamine could serve as potential markers for evaluating the quality change of camel meat at different slaughter ages.