摘要
目的:建立茶叶中茶氨酸、5种儿茶素类(+C、EC、EGC、EGCG、ECG)、总黄酮和咖啡因含量测定的HPLC法,并对南岳云雾茶的品质进行评价.方法:茶叶中有效成分的提取参照GB/T 8303-2018,分析采用安捷伦Eclipse XDB-C18色谱柱(4.6 mm×250 mm,5 μm),流动相为2％乙酸水(A)-2％乙酸乙腈(B),流速0.8mL/min-1,柱温25 ℃,检测波长为203 nm、278 nm、360 nm.结果:方法学结果显示+C、EC、EGC、EGCG、ECG、咖啡因、L-茶氨酸及芦丁分别在 50.00 μg·mL-1～150.00 μg·mL-1,50.00 μg·mL-1～150.00 μg·mL-1,50.00 μg·mL-1～1 50.00 μg·mL-1,100.00 μg·mL-1～250.00 μg·mL-1,100.00 μg·mL-1～300.00 μg·mL-1,10.00 μg·mL-1～1 00.00 μg·mL-1,100.00 μg·mL-1～400.00 μg·mL-1及10.00 μg·mL-1～100.00 μg·mL-1浓度范围内线性关系良好,加样回收率为92.49％-105.56％.在上述条件下,测得南岳云雾茶中茶氨酸、儿茶素类、总黄酮和咖啡因的含量分别为67.32 mg/g、260.4 2mg/g、3.712 mg/g和34.05 mg/g.结论:南岳云雾茶中茶氨酸、儿茶素类及总黄酮的含量相对较高.该方法简便、准确、快速、重现性好,可为茶叶的质量控制提供科学的依据.
Abstract
Objective:A HPLC method for the determination of theanine,five catechins(+C,EC,EGC,EGCG,ECG),total flavonoids and caffeine in tea was established,and the quality of Nanyue Yunwu tea was evaluated.Methods:According to GB/T 8303-2018,the effective components in tea were extracted and deteminated by Agilent Eclipse XDB-C18 chromatographic column(4.6 mm×278 nm,5 μm),mobile phase was 2％acetic acid water(A)-2％acetic acid acetonitrile(b),flow rate was 0.8 mL·min-1,column temperature was 30 ℃,and detection wavelengths were 203 nm,278 nm,360 nm,respectively.Results:The results of methodology showed that+C,EC,EGC,EGCG,ECG,caffeine,L-theanine and rutin were 50.00 μg·mL-1～150.00 μg·mL-1,50.00 μg·mL-1～150.00 μg·mL-1,100.00 μg·mL-1～200 μg·mL-1 respectively.The linear relationship is good in the concentration ranges of 10.00 μg·mL-1～100.00 μg·mL-1,100.00 μg·mL-1～400.00 μg·mL-1 and 10.00 μg·mL-1～100.00 μg·mL-1,and the recovery rate is 92.49％～105.56％.The results of methodology showed that the linear relationships of+C,EC,EGC,EGCG,ECG,caffeine,L-theanine and rutin were good in the concentration ranges of 50.00～150.00 μg·mL-1,50.00 μg·mL-1～150.00 μg·mL-1,50.00～150.00 μg·mL-1,100.00 μg·mL-1～250 μg·mL-1,100.00 μg·mL-1～300.00 μg·mL-1,10.00 μg·mL-1～100.00 μg·mL-1 and 100.00 μg·mL-1～400.00 μg·mL-1,respectively.And the recovery rate ranged from 92.49％-105.56％.Under the above conditions,the contents of theanine,catechins,total flavonoids and caffeine in Nanyue Yunwu tea were 67.32 mg·g-1,260.42 mg·g-1,3.712 mg·g-1 and 34.05 mg·g-1,respectively.Conclusion:The contents of theanine,catechins and total flavonoids in Nanyue Yunwu tea are relatively high.The method is simple,accurate,rapid and reproducible,and can provide scientific basis for the quality control of tea.
维普
万方数据