测定了本山、黄旦和铁观音三个品种茶树成熟叶片的总酚及可溶缩合单宁含量,并通过基质辅助激光解吸附飞行时间质谱(MALDI-TOFMS)研究了茶叶缩合单宁的基本结构。结果显示,三种茶叶均具有较高的总酚含量,大约为200mg/g;三种茶叶的缩合单宁是以(表)儿茶素(EC/C)和(表)棓儿茶素(EGC/GC)为基本结构单元的均聚物和杂聚物,且大部分聚合物的结构单元之间存在A型和B型两种连接方式,其中本山和黄旦缩合单宁的最高聚合度要大于铁观音。
The contents of total polyphenols and extractable condensed tannins in leaves of three types of Camellia sinensis (Benshan,Huangdan and Tieguanyin) were determined. In addition,the structures of condensed tannins were characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Three types of tea leaves have total phenolic contents as high as 200 mg/g. The majority of condensed tannins in the three types of C. sinensis are identified as the mixtures of procya...