不同品质青稞种子的广泛靶向代谢组学研究

通过测定蛋白质、淀粉、β-葡聚糖和γ-氨基丁酸等品质指标含量，从81个西藏青稞种质资源中挑选出3种不同品质级别的青稞：品质较好的为比如青稞，品质中等的为曲水青稞，品质较差的为巴日白青稞，利用LC-MS/MS对不同品质的青稞种子中代谢物的变化进行研究。结果表明：比如青稞和巴日白青稞（56个代谢物上调，206个下调）、比如青稞和曲水青稞（179个上调，82个下调）、曲水青稞和巴日白青稞（58个上调，240个下调）差异表达显著的代谢物总数分别为262、261、298。差异倍数分析发现，和巴日白青稞相比，比如青稞上调的代谢物主要是酚酸类物质；和曲水青稞相比，比如青稞上调的代谢物主要是花青素类物质；和巴日白青稞相比，曲水青稞上调的代谢物主要是黄酮碳糖苷类物质。代谢通路富集分析结果表明，和品质较差的青稞相比，品质较好青稞的差异代谢物共富集在65条代谢通路上，主要是氨基酸的生物合成、氨酰生物合成、类黄酮生物合成等通路富集显著。和品质中等的青稞相比，品质较好青稞上调的差异代谢物共富集在65条代谢通路上，主要是氨基酸的生物合成、氨酰生物合成和2-氧代环戊烷羧酸甲酯代谢等通路显著富集；和品质较差的青稞相比，品质中等青稞的差异代谢物共富集在61条代谢通路上，主要是黄酮和黄酮醇的生物合成、嘌呤代谢、嘧啶代谢、氨酰生物合成。

Broadly targeted metabolomics study of highland barley seeds of different qualities

Three representative highland barley of good quality, medium quality and poor quality were selected from 81 Tibetan highland barley according to the content of quality indexes (protein, starch, β-glucan, γ-aminobutyric acid). ‘Biru’ highland barley was selected as the good quality, ‘Qushui’ highland barley was selected as the medium quality and ‘Baribai’ highland barley was selected as the poor quality. The changes of metabolites in barley seeds of different quality were studied by LC-MS/MS. The total number of differentially expressed metabolites between ‘Biru’ and ‘Baribai’ (56 up|regulated, 206 down|regulated), ‘Biru’ and ‘Qushui’ (179 metabolites up|regulated, 82 down|regulated), ‘Qushui’ and ‘Baribai’ (58 up|regulated, 240 down|regulated) was 262, 261 and 298, respectively. Difference fold analysis found that phenolic acids was the main metabolite of the high quality compared with the low quality, and anthocyanins was the main metabolites of the high quality compared with the medium quality. The results of metabolic pathway enrichment analysis showed that the differential metabolites of high quality were enriched in 65 pathways, mainly in amino acid biosynthesis, aminoacyl biosynthesis and flavonoid biosynthesis. Compared with medium quality, the up|regulated differential metabolites of high quality were enriched in 65 pathways, mainly in amino acid biosynthesis, aminoacyl biosynthesis and 2-oxy-cyclopentane methyl ester metabolism. Compared with the low quality, the differential metabolites of medium quality were enriched in 61 pathways, mainly including biosynthesis of flavonoids and flavonols, purine metabolism, pyrimidine metabolism and aminoacyl biosynthesis.