通过模拟Pb污染区大麦种植，本研究采用液相色谱-质谱联用（LC-MS）代谢组学技术，结合主成分分析（PCA）、正交偏最小二乘法-判别分析（OPLS-DA）、层次聚类分析等多元统计学分析，探究Pb在大麦中的代谢通路及对大麦代谢物的动态变化影响。实验选用成苗期大麦（CMQ）和经Pb胁迫大麦（CMQPb）两组样本。共定性出84个代谢物，通过对显著代谢物进行筛选（p<0.05）共得到60个差异代谢物，发现Pb胁迫对大麦中有机酸及其衍生物、多酚类物质、多胺类物质、脂类及类脂质分子含量影响较大，说明Pb胁迫会对大麦苗营养成分产生一定影响。通过KEGG代谢通路分析，发现Pb胁迫对β-丙氨酸代谢影响最大。β-丙氨酸、二氢尿嘧啶、泛酸和尿嘧啶4个差异代谢物对大麦受Pb胁迫后的差异代谢分析具有重要意义。

By simulating barley cultivation in Pb-contaminated area, this study used liquid chromatography-mass spectrometry (LC-MS) metabolomics technology, combined with multivariate statistical analyses such as principal component analysis (PCA), orthogonal partial least squares-discriminant analysis (OPLS-DA), and hierarchical clustering analysis to explore the metabolic pathway of Pb in barley and its influence on the dynamic changes of barley metabolites. Two groups of samples of barley at seedling stage (CMQ) and Pb-stressed CMQ (CMQPb) were selected in the experiment. A total of 84 metabolites were identified, and 60 differential metabolites were obtained by screening the significant metabolites (p<0.05). It was found that Pb stress had a great influence on the contents of organic acids and their derivatives, polyphenols, polyamines, lipids and lipid-like molecules in barley. These results indicate that Pb stress had a certain impact on the nutritional components of barley seedlings. Through the analysis of KEGG metabolic pathway, it was found that Pb stress had the greatest impact on β-alanine metabolism. The four differential metabolites of β-alanine, dihydrouracil, pantothenic acid and uracil are of great significance for the differential metabolic analysis of barley under Pb stress.

国家重点研发计划项目（2018YFE0206300）；杂粮及制品安全风险评估及标准体系建设项目（2018YFE0206300-10）；黑龙江省优势特色学科资助项目（黑教联[2018]4号）；黑龙江八一农垦大学研究生创新科研资助项目（YJSCXZ2021-Y77）