Keemun black tea stems and leaves:comparison of chemical characterization and anti-inflammatory activities  

作　　者：Mengting Zhu Xiaoqing Rong Mingchun Wen Piaopiao Long Zongde Jiang Wen Xu Daniel Granato Liang Zhang 

机构地区：[1]State Key Laboratory of Tea Plant Biology and Utilization,Anhui Agricultural University,Hefei 230036,China [2]International Joint Laboratory on Tea Chemistry and Health Effects of Ministry of Education,Anhui Agricultural University,Hefei 230036,China [3]Key Laboratory of Quality Evaluation of Chinese Medicine of the Guangdong Provincial Medical Products Administration,the Second Clinical College,Guangzhou University of Chinese Medicine,Guangzhou 510006,China [4]Bioactivity&Applications Lab,Department of Biological Sciences,Faculty of Science and Engineering,University of Limerick,Limerick V94 T9PX,Ireland

出　　处：《Food Science and Human Wellness》2025年第4期1546-1556,共11页食品科学与人类健康(英文)

基　　金：supported by the Natural Science Foundation of China(32122079,32072633);Earmarked Fund for China Agriculture Research System(CARS-19);Anhui Key Research and Development Plan(202104b11020001);Young Elite Scientist Sponsorship Program by National CAST(2016QNRC001);High-level Introduced Talent Sponsorship Program by Anhui Agricultural University(rc352203)。

摘　　要：This work aims to compare the chemical composition and anti-inflammatory effects on RAW264.7 macrophages of Keemun black tea stems and leaves.A total of 50 volatile compounds were identified in tea stems and leaves,and aldehydes,alcohols,and esters were the main volatile compound categories.There were 11 key volatile compounds,including geraniol,benzeneacetaldehyde,methyl salicylate,linalool,etc.contributed to distinguishing the tea stems from the tea leaves.In the quantitative and liquid chromatography-mass spectrometry(LC-MS)-based metabolomics analysis,higher contents of amino acids,monosaccharides,and quinic acids were found in stems than those in leaves.Inversely,higher contents of tea pigments,flavan-3-ols,gallic acid,purine alkaloids,and flavonol glycosides were present in tea leaves than in stems.LC-MS-based metabolomics also revealed that organic acids were the most critical non-volatile compounds responsible for the differences between tea stems and leaves.Furthermore,tea stems had better inhibiting effects of pro-inflammatory cytokines(interleukin(IL)-1βand IL-6)in lipopolysaccharide-challenged RAW264.7 macrophages than tea leaves,while no significant differences exist between leaves and stems for inhibiting the secretion of tumor necrosis factorα(TNF-α)and NO.In conclusion,our results support using Keemun black tea stems as a novel source of anti-inflammatory compounds.

关 键 词：Black tea stems Volatile compounds Non-volatile compounds Anti-inflammatory activities CYTOKINES 

分 类 号：TS209[轻工技术与工程—食品科学]