中国农业科学 ›› 2022, Vol. 55 ›› Issue (4): 769-784.doi: 10.3864/j.issn.0578-1752.2022.04.012

• 园艺 • 上一篇    下一篇

基于代谢组学的‘永春佛手’乌龙茶化学成分解析

彭佳堃1,2(),戴伟东1(),颜涌泉3,张悦1,陈丹1,董明花3,吕美玲4,林智1()   

  1. 1中国农业科学院茶叶研究所/农业部茶树生物学与资源利用重点实验室,杭州 310008
    2中国农业科学院研究生院,北京 100081
    3永春县农业农村局,福建泉州 362600
    4安捷伦科技(中国)有限公司,北京 100102
  • 收稿日期:2021-04-07 接受日期:2021-07-01 出版日期:2022-02-16 发布日期:2022-02-23
  • 通讯作者: 戴伟东,林智
  • 作者简介:彭佳堃,E-mail: pengjiakun@tricaas.com
  • 基金资助:
    国家自然科学基金(31972467);国家现代农业产业技术体系资助(CARS-19)

Study on the Chemical Constituents of Yongchun Foshou Oolong Tea Based on Metabolomics

PENG JiaKun1,2(),DAI WeiDong1(),YAN YongQuan3,ZHANG Yue1,CHEN Dan1,DONG MingHua3,LÜ MeiLing4,LIN Zhi1()   

  1. 1Tea Research Institute, Chinese Academy of Agricultural Sciences/Key Laboratory of Tea Biology and Resource Utilization of Ministry of Agriculture, Hangzhou 310008
    2Graduate School of Chinese Academy of Agricultural Sciences, Beijing 100081
    3Yongchun Agricultural and Rural Bureau, Quanzhou 362600, Fujian
    4Agilent Technologies (China) Co., Ltd., Beijing 100102
  • Received:2021-04-07 Accepted:2021-07-01 Online:2022-02-16 Published:2022-02-23
  • Contact: WeiDong DAI,Zhi LIN

摘要:

【目的】不同茶树品种制作的乌龙茶风味品质和内含成分具有明显差异。本研究结合非靶向代谢组学、化合物定量分析、多元统计学等方法比较‘永春佛手’‘铁观音’和‘水仙’乌龙茶的化学成分差异,分析‘永春佛手’乌龙茶的特征性化学成分,并探讨茶树品种对乌龙茶内含成分和感官品质的影响。【方法】以‘永春佛手’品种为主要研究对象,‘铁观音’和‘水仙’品种为对照,三者均加工制成清香型、浓香型和陈香型乌龙茶,采用超高效液相色谱-四级杆-飞行时间质谱(UHPLC-Q-TOF/MS)进行非靶向代谢组学分析,对不同品种乌龙茶的差异化合物进行鉴定和筛选,并采用超高效液相色谱仪、氨基酸分析仪和超高效液相色谱-四极杆-静电场轨道阱质谱(UHPLC-Q-Orbitrap-MS)对茶叶中主要化学成分和不同品种乌龙茶间差异化合物进行定量分析。【结果】相比于同一香型的对照品种乌龙茶,‘永春佛手’具有相对较高的氨基酸总量和茶氨酸含量,儿茶素类化合物总量和咖啡碱含量在清香型和浓香型的不同品种间无显著差异,在陈香型中均以‘永春佛手’乌龙茶含量最高,没食子酸含量在3种香型中均呈现‘水仙’>‘永春佛手’>‘铁观音’。代谢组学结合多变量统计表明,不同品种制成的乌龙茶化合物表型具有明显差异。清香型、浓香型和陈香型乌龙茶中,‘永春佛手’与对照品种乌龙茶间的差异化合物分别为50、59、47个,其中共同差异化合物有23个,包括14个黄酮(醇)糖苷、5个儿茶素类化合物及其衍生物、1个脂类、1个生物碱、1个有机酸和1个氨基酸类化合物。进一步对茶叶中常见的20个黄酮(醇)糖苷组分进行定量分析,结果显示‘永春佛手’乌龙茶中14个黄酮(醇)糖苷组分的含量显著高于对照品种乌龙茶,其含量是相同香型‘铁观音’品种乌龙茶的1.4—14.6倍,是‘水仙’品种乌龙茶的1.3—18.0倍。在定量的4类黄酮(醇)糖苷中,槲皮素糖苷均为主要的黄酮(醇)糖苷组分,含量高于山柰酚糖苷、杨梅素糖苷和芹菜素糖苷。感官审评分析表明较高含量的黄酮(醇)糖苷并未显著增强茶汤的涩味。【结论】代谢组学方法可以有效地对不同品种制作的乌龙茶进行化合物表征。‘永春佛手’‘铁观音’和‘水仙’按照相同工艺制成的乌龙茶具有较为明显的化学成分差异,其中黄酮(醇)糖苷类化合物差异最为显著,具有较高含量的黄酮(醇)糖苷类成分是‘永春佛手’乌龙茶在化学成分方面的一个重要特征。黄酮(醇)糖苷类成分有望作为判别指标用于乌龙茶制作品种的判别。

关键词: 乌龙茶, 品种特征成分, 代谢组学, 液质联用, 黄酮(醇)糖苷

Abstract:

【Objective】 Oolong teas made with different tea cultivars have a great difference in flavor and chemical components. In this study, non-targeted metabolomics, absolute quantitative analysis, and multivariate statistics analysis were used to investigate the chemical differences among Yongchun Foshou (YCFS), Tieguanyin (TGY) and Shuixian (SX) oolong tea and to screen characteristic chemical components of YCFS oolong tea, as well as to study the influence of tea cultivars on chemical components and sensory quality of oolong tea. 【Method】 Camellia sinensis cv. Foshou was used as the main research sample and Camellia sinensis cv. Tieguanyin and Camellia sinensis cv. Shuixian were used as the controls. Three tea cultivars were manufactured into fresh-scent, strong-scent and aged-scent oolong teas. Ultra-high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UHPLC-Q-TOF/MS) was used for non-targeted metabolomics analysis to screen differential compounds in the oolong teas made from different cultivars. In addition, ultra-high performance liquid chromatograph, amino acid analyzer and ultra-high performance liquid chromatography-quadrupole-orbitrap-mass spectrometry (UHPLC-Q-Orbitrap-MS) was applied for absolute quantifications of main chemical constituents and differential compounds in oolong teas made from different tea cultivars. 【Result】 Compared with the control oolong teas of same scent type, YCFS oolong tea had relatively higher contents in total amino acid and theanine. The contents of total catechins and caffeine were not significantly different among the 3 cultivars in fresh-scent and strong-scent oolong teas, which were the highest in YCFS in aged-scent oolong teas. The content of gallic acid was SX>YCFS>TGY in 3 scent types oolong teas. Metabolomics analysis combined with multivariate statistics analysis showed that the compound patterns in oolong teas made from different tea cultivars were significantly different. In fresh-scent, strong-scent and aged-scent oolong teas, there were 50, 59 and 47 differential compounds between YCFS and control cultivar, respectively. Among them, 23 differential compounds were common, including 14 flavone (flavonol) glycosides, 5 catechins and their derivatives, 1 lipid, 1 alkaloid, 1 organic acid and 1 amino acid. Further quantitative analysis of 20 main flavone (flavonol) glycosides showed that the contents of 14 flavone (flavonol) glycosides were the highest in YCFS oolong teas, whose contents were 1.4 to 14.6-fold of that in TGY oolong teas and were 1.3 to 18.0-fold of that in SX oolong teas. Among four kinds of flavone (flavonol) glycosides, quercetin glycosides were the main flavone (flavonol) glycosides with higher contents than glycosides of kaempferol, myricetin and apigenin. Sensory evaluation combined with chemical composition results showed that the higher contents of flavone (flavonol) glycosides did not significantly enhance the astringency of YCFS oolong tea infusions. 【Conclusion】 The metabolomics method effectively characterized the component differences in oolong teas made from different tea cultivars in this study. There were obvious differences in compound patterns among YCFS, TGY and SX oolong teas. Flavone (flavonol) glycosides were the most significantly differential compounds. The higher content of flavone (flavonol) glycosides was a major chemical feature of YCFS oolong tea and was expected to be used as a discriminant index for the identification of oolong tea cultivar in the future.

Key words: oolong tea, cultivar-characteristic components, metabolomics, LC-MS, flavone (flavonol) glycoside