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Updated: Jun 14, 2026
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Caffeine Extraction, Enzymatic Activity and Gene Expression of Caffeine Synthase from Plant Cell Suspensions
Published on: October 2, 2018
[Theanine, EGCG and caffeine determinated by HPLC]
Feiyan Diao1, Fengming Dong, Qiuli Wang
1Department of Chemical and Bacterial Detection, School of Public Health, Shandong University, Ji'nan 250012, China. diaofeiyan321@163.com
Wei Sheng Yan Jiu = Journal of Hygiene Research
|April 7, 2010
Summary
A new high-performance liquid chromatography (HPLC) method accurately determines theanine, EGCG, and caffeine in puer tea. This validated approach offers reliable analysis for these key tea components.
Area of Science:
- Analytical Chemistry
- Food Science
Context:
- Puer tea analysis requires accurate quantification of bioactive compounds.
- Existing methods for theanine determination often involve derivatization.
- Simultaneous analysis of theanine, EGCG, and caffeine presents challenges.
Purpose:
- To develop a high-performance liquid chromatography (HPLC) method for theanine determination without derivatization.
- To establish an HPLC method with a specific elution system for quantifying EGCG and caffeine in puer tea.
Summary:
- Water extraction was used for theanine, while a water:ethanol mixture (3:7) with ultrasonic oscillation was employed for EGCG and caffeine extraction.
- HPLC-PDAD with a C18 column was utilized, employing distinct mobile phase systems for theanine (SDS-acetonitrile) and for EGCG and caffeine (KH2PO4-methanol).
- The developed method demonstrated good linearity, recovery rates between 85%-110%, and relative standard deviation (RSD) below 10% for all three compounds.
Impact:
- Provides an accurate, stable, and efficient analytical method for key puer tea constituents.
- Facilitates quality control and research in the tea industry.
- Eliminates the need for derivatization in theanine analysis, simplifying the process.
