摘要
目的 建立多维度分析体系,比较不同品种、不同生长期茶叶中的咖啡因、茶多酚含量及微量元素组成的差异,为茶叶品质评价及临床应用提供科学依据。方法 选用金井红茶、安化红茶2个茶叶样品及城步峒茶2019—2024年间的6个茶叶样品为主要研究样本,采用高效液相色谱法、紫外分光光度法、电感耦合等离子体质谱法,分别测定其咖啡因、茶多酚及微量元素含量。结果 8种茶叶咖啡因含量为2.60%~3.82%,其中城步峒茶2023年的含量最高(3.82%),2019—2022年呈波动下降。茶多酚含量为20.19%~31.05%,城步峒茶2024年达峰值(26.13%),突破2019—2023年的区间(20.19%~24.25%),为近6年最高值,增幅显著。主要微量元素锰(244 633~479 394 ppb)、铜(8 436~15 430 ppb)、锶(4 474~13 286 ppb)、镍(3 413~14 376 ppb)等含量较高,其中城步峒茶2021年的锰含量突出(479 394 ppb),且重金属含量均符合相关标准规定。结论 不同品种和不同生长期的茶叶中咖啡因和茶多酚含量存在明显差异。城步峒茶咖啡因含量整体偏高,其茶多酚含量随生长期的不同稍有差异。城步峒茶重金属含量均符合要求,各微量元素质量浓度呈现特异性,与其土壤富集或品种特性相关。本研究可为茶叶资源的精准利用及功能产品开发提供数据支撑。
Objective To establish a multidimensional analysis system for comparing the differences in caffeine,tea polyphenol content,and trace element composition among tea leaves from different cultivars and growth stages,thereby providing a scientific basis for tea quality evaluation and clinical applications.Method Two tea samples,namely Jinjing black tea and Anhua black tea,along with six samples of Chengbu Dong tea collected between 2019 and 2024,were selected as the primary research subjects.High-performance liquid chromatography(HPLC),ultraviolet-visible spectrophotometry(UV-Vis),and inductively coupled plasma mass spectrometry(ICP-MS)were employed to quantify the content of caffeine,tea polyphenols,and trace elements,respectively.Results The caffeine content in the eight tea samples ranged from 2.60%to 3.82%,with Chengbu Dong tea from 2023 exhibiting the highest level(3.82%).A fluctuating decline was observed from 2019 to 2022.The tea polyphenol content ranged from 20.19%to 31.05%,reaching a peak in Chengbu Dong tea from 2024(26.13%),which surpassed the range observed from 2019 to 2023(20.19%-24.25%)and marked the highest value in six years,with a notable increase.The primary trace elements,including manganese(244,633-563,168 ppb),copper(8,43617,682 ppb),strontium(4,474-13,286 ppb),and nickel(3,413-14,376 ppb),were present at relatively high levels.Notably,the manganese content in Chengbu Dong tea from 2021 was particularly prominent(479,394 ppb),and all heavy metal content complied with relevant standards.Conclusion Significant differences exist in the caffeine and tea polyphenol content among tea leaves from different cultivars and growth stages.Chengbu Dong tea generally exhibits higher caffeine content,with slight variations in tea polyphenol content across different growth stages.The heavy metal content in Chengbu Dong tea meet regulatory requirements,while the concentrations of various trace elements demonstrate specificity,likely associated with soil enrichment or cultivar characteristics.This study provides data support for the precise utilization of tea resources and the development of functional tea products.
作者
李强
肖敦旺
肖娟
张新
陈雨迪
索俪榕
LI Qiang;XIAO Dunwang;XIAO Juan;ZHANG Xin;CHEN Yudi;SUO Lirong(Chengbu Baiyun Lake Ecological Agriculture Development Co.,Ltd.,Shaoyang,Hunan 422500,China;Hunan Hengtian Pharmaceutical Technology Co.,Ltd.,Changsha,Hunan 41000o,China)
基金
2019年城步苗族自治县重点产业扶贫项目(湘财预[2019]73号)。
关键词
茶叶
茶多酚
咖啡因
微量元素
高效液相色谱法
紫外分光光度法
tea leaves
tea polyphenols
caffeine
trace elements
high-performance liquid chromatography
ultravioletvisible spectrophotometry
