基于非靶向代谢组学比较手工和机制信阳毛尖的代谢物差异

目的 探明两种加工方式对信阳毛尖的化学成分影响。方法 以信阳群体种一芽一叶为原料,分别按照手工和机制方式加工信阳毛尖,采用超高效液相色谱-四极杆-静电轨道阱质谱(UHPLC-Q-Exactive/MS)对非挥发性化合物进行分析。结果 本研究共鉴定出93个化合物,包括生物碱类、氨基酸类、儿茶素类、二聚儿茶素类、黄酮(醇)糖苷类、酚酸类、核苷类等。采用主成分分析(PCA)和正交偏最小二乘法判别分析(OPLS-DA)等方法,对手工和机制加工信阳毛尖过程样的研究表明：手工和机制加工过程样可以通过化学成分的组成进行较好的区分,进一步分析两种加工方式发现了40种差异化合物,其中黄酮(醇)糖苷类和氨基酸是差异最明显的两大类成分,机制茶加工过程样中黄酮(醇)糖苷类和氨基酸含量高于手工制作,差异显著的主要成分有L-丙氨酸、γ-氨基丁酸、槲皮素3-O-葡萄糖芸香糖苷和槲皮素等。手工茶制作过程中,杀青温度较低、时间相对较长,从而产生了更多的表阿夫儿茶精-3-没食子酸酯、原花青素B1、聚酯型儿茶素A和茶黄素双没食子酸酯等二聚物。此外,手工茶的多数酚酸类化合物,以及一磷酸腺苷和磷酸甘油胆碱等含量高于机制茶。结论 本研究采用代谢组学方法较为系统的分析了手工和机制信阳毛尖加工过程中的差异化合物,为信阳毛尖手工茶和机制茶品质差异评价及加工技术提升提供了理论依据。

Comparison of Metabolite Differences between Handmade and Machine-made Xinyang Maojian Based on Non-Targeted Metabolomics

Objective To investigate the impact of two processing methods on the chemical composition of Xinyang Maojian. Methods Xinyang Maojian was processed manually and mechanically that used one bud and one leaf of Xinyang Population, An ultrahigh performance liquid chromatography-quadrupole orbitrap mass spectrometer (UHPLC-Q-Exactive/MS) was applied to analyze the non-volatile chemical components. Results A total of 93 compounds were structurally identified in this study, including alkaloids, amino acids, catechins, dimeric catechins, flavonoid (alcohol) glycosides, phenolic acids, nucleosides, etc. The study between the mandmade and machine-made Xinyang Maojian processing was analysised by principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA), handmade and machine-made processing samples could be well distinguished by the chemical components, it got 40 differential compounds after further analysis of two sets of process samples, among them, flavonoid (alcohol) glycosides and amino acids were the most differential components, L-alanine γ- Aminobutyric acid, Quercetin 3-O-glucosylrutinoside, and Quercetin in handmade tea were lower than machine-made tea, handmade tea had more dimers catechins such as Epiafzelechin 3-gallate, Procyanidin B1, Theasininsin A, and TFDG due to its low fixation temperature and long time. In addition, most phenolic acid compounds, as well as AMP and Glycerophorine, in handmade tea were higher than those in machine-made tea. Conclusion This study systematically analyzed the differential compounds in the manual and mechanical processing of Xinyang Maojian used metabolomics methods, as well as provided theoretical basis for evaluating the quality differences and improving the processing technology between handmade and machine-made Xinyang Maojian tea.